Final Evidence Summary
Breastfeeding: Counseling
October 15, 2008
Recommendations made by the USPSTF are independent of the U.S. government. They should not be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.
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By Mei Chung, MPH; Gowri Raman, MD; Thomas Trikalinos, MD, PhD; Joseph Lau, MD; and Stanley Ip, MD.
Corresponding Author: Mei Chung, MPH, Center for Clinical Evidence Synthesis, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box 63, Boston, MA 02111; E-mail, mchung1@tuftsmedicalcenter.org.
This study was conducted by the Tufts-New England Medical Center Evidence-based Practice Center under contract to the Agency for Healthcare Research and Quality, Rockville, Maryland (contract no. 290-02-0022).
The information in this report is intended to help clinicians, employers, policymakers, and others make informed decisions about the provision of health care services. This report is intended as a reference and not as a substitute for clinical judgment.
This report may be used, in whole or in part, as the basis for the development of clinical practice guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage policies. AHRQ or U.S. Department of Health and Human Services endorsement of such derivative products may not be stated or implied.
This report was first published in Annals of Internal Medicine in September 2008 (Ann Intern Med 2008;149:565-82; https://www.annals.org).
Background: Evidence suggests that breastfeeding decreases the risk for many diseases in mothers and infants. It is therefore important to evaluate the effectiveness of breastfeeding interventions.
Purpose: To systematically review evidence for the effectiveness of primary care-initiated interventions to promote breastfeeding with respect to breastfeeding and child and maternal health outcomes.
Data Sources: Electronic searches of MEDLINE®, the Cochrane Central Register of Controlled Trials, and CINAHL from September 2001 to February 2008 and references of selected articles, restricted to English-language publications.
Study Selection: Randomized, controlled trials of primary care-initiated interventions to promote breastfeeding, mainly in developed countries.
Data Extraction: Characteristics of interventions and comparators, study setting, study design, population characteristics, the proportion of infants continuing breastfeeding by different durations, and infant or maternal health outcomes were recorded.
Data Synthesis: Thirty-eight randomized, controlled trials (36 in developed countries) met eligibility criteria. In random-effects metaanalyses, breastfeeding promotion interventions in developed countries resulted in significantly increased rates of short- (1 to 3 months) and long-term (6 to 8 months) exclusive breastfeeding (rate ratios, 1.28 [95% CI, 1.11 to 1.48] and 1.44 [CI, 1.13 to 1.84], respectively). In subgroup analyses, combining pre- and postnatal breastfeeding interventions had a larger effect on increasing breastfeeding durations than either pre- or postnatal interventions alone. Furthermore, breastfeeding interventions with a component of lay support (such as peer support or peer counseling) were more effective than usual care in increasing the short-term breastfeeding rate.
Limitations: Meta-analyses were limited by clinical and methodological heterogeneity. Reliable estimates for the isolated effects of each component of multicomponent interventions could not be obtained.
Conclusion: Evidence suggests that breastfeeding interventions are more effective than usual care in increasing short- and long-term breastfeeding rates. Combined pre- and postnatal interventions and inclusion of lay support in a multicomponent intervention may be beneficial.
Human milk is the natural nutrition for all infants. According to the American Academy of Pediatrics, it is the preferred choice of feeding for all infants.1 The goals of Healthy People 2010 for breastfeeding are an initiation rate of 75% and continuation rate of 50% at 6 months and 25% at 12 months after delivery.2 A survey of U.S. children in 2002 indicated that only 71% had ever been breastfed, and the percentage of infants who continue to be breastfed to some extent is 35% at 6 months and 16% at 12 months.3 Although the breastfeeding initiation rate is close to the goal set by Healthy People 2010, according to this survey, the breastfeeding continuation rates at 6 and 12 months fall short.
Evidence suggests that breastfeeding decreases risks for many diseases in infants and mothers. In children, breastfeeding has been associated with a reduction in the risk for acute otitis media, nonspecific gastroenteritis, severe lower respiratory tract infections, atopic dermatitis, childhood leukemia, and the sudden infant death syndrome. In mothers, a history of lactation has been associated with a reduced risk for type 2 diabetes and breast and ovarian cancer.4 According to the American Academy of Pediatrics, some of the obstacles to initiation and continuation of breastfeeding include insufficient prenatal education about breastfeeding, disruptive maternity care practices, and lack of family and broad societal support.5 Effective interventions reported to date include changes in maternity care practices, such as those implemented in pursuit of the Baby-Friendly Hospital Initiative (BFHI) designation6,7 and worksite lactation programs.8 Some of the other interventions implemented include peer-to-peer support, maternal education, and media marketing.9
Our review is based on an evidence report10 that was requested by the Center on Primary Care, Prevention, and Clinical Partnerships at the Agency for Healthcare Research and Quality, on behalf of the U.S. Preventive Services Task Force, to support the Task Force's update of its 2003 recommendations on counseling to promote breastfeeding.11 Together with the Tufts Evidence-based Practice Center, these agencies jointly developed an analytic framework for study questions to evaluate the available evidence to promote and support breastfeeding (Figure 1). Five linked key questions were proposed in the analytic framework:
- What are the effects of breastfeeding interventions on child and maternal health outcomes?
- What are the effects of breastfeeding interventions on breastfeeding initiation, duration, and exclusivity?
- Are there harms from interventions to promote and support breastfeeding?
- What are the benefits and harms of breastfeeding on infant or child health outcomes?
- What are the benefits and harms of breastfeeding on maternal health outcomes?
The contextual questions regarding the effectiveness of health care system influences on interventions to promote breastfeeding and the potential benefits and harms related to such interventions can be answered by synthesizing the available scientific evidence for each key question. To avoid redundant work, a joint decision was made to adopt results from our earlier Agency for Healthcare Research and Quality evidence report4 to address questions 4 and 5 on the benefits and harms of breastfeeding for infants and mothers. Table 112-84 presents a synopsis of that report's findings on questions 4 and 5. We address only questions 1 to 3 in this article. Specifically, we examine the effects of primary care-initiated interventions to support or promote breastfeeding on child and maternal health outcomes and breastfeeding rates, as reported in randomized, controlled trials (RCTs) from developed countries. We also document reported harms from interventions to promote and support breastfeeding.
Data Sources
This systematic review focuses on recent evidence (September 2001 to February 2008) and updates a previous systematic review85 conducted for the U.S. Preventive Services Task Force to support its 2003 recommendation on counseling to promote breastfeeding. We searched for English-language articles in MEDLINE®, the Cochrane Central Register of Controlled Trials, and CINAHL from September 2001 to February 2008 by using such Medical Subject Heading terms and keywords as breastfeeding, breast milk feeding, breast milk, human milk, nursing, breastfed, infant nutrition, lactating, and lactation. We also reviewed reference lists of a related systematic review86 for additional studies.
Study Selection
We included RCTs published from September 2001 to February 2008 that included any counseling or behavioral intervention initiated from a clinician's practice (office or hospital) to improve the breastfeeding initiation rate or duration of breastfeeding among healthy mothers or members of the mother-child support system (such as partners, grandparents, or friends) and their healthy term or near-term infants (≥35 weeks' gestation or ≥2500 g). We focused our review on studies conducted in developed countries; however, because of the widespread interest in the BFHI, we also included RCTs of the BFHI that were conducted in Brazil and Belarus.
We considered interventions conducted by various providers (lactation consultants, nurses, peer counselors, midwives, and physicians) in various settings (hospital, home, clinic, or elsewhere) to be eligible as long as they originated from a health care setting. We considered maternity services to be primary care for this review. We also included such health care system interventions as staff training. We excluded community- or peer-initiated interventions. Control comparisons were any usual prenatal, peripartum, or postpartum care, as defined in each study. Studies needed to report rates of breastfeeding initiation, duration of breastfeeding, or exclusivity of breastfeeding to be included. Figure 2 shows our search and selection process.
Data Extraction and Quality Assessment
One investigator extracted data from each study, and another confirmed them. The extracted data included study setting, population, control, description of intervention (type, person, frequency, and duration), definitions of breastfeeding outcomes (initiation, exclusivity, and duration), definitions of health outcomes in both mothers and children (when provided), and analytic methods.
Classification of Breastfeeding Interventions
Breastfeeding interventions can include a combination of individual components, such as structured breastfeeding education or professional or lay support. We defined 3 categories of breastfeeding intervention: those that included a component of formal or structured breastfeeding education, those that included a component of either professional or lay breastfeeding support, or those that did not include the aforementioned components. The first 2 categories are not mutually exclusive. Table 2 shows complete details.
Definitions
We classified breastfeeding regimens as exclusive or nonexclusive. Studies used different definitions of exclusive breastfeeding ("no supplement of any kind," "including water while breastfeeding," or "occasional formula is permissible while breastfeeding"); we adopted all of those definitions. We classified all other breastfeeding regimens (full, partial, mixed, or nonspecified) as nonexclusive.
We defined breastfeeding initiation as any breastfeeding at discharge or up to 2 weeks after delivery. We also defined a priori breastfeeding durations of 1 to 3 months as short-term, 4 to 5 months as intermediate-term, 6 to 8 months as long-term, and 9 or more months as prolonged. We categorized studies with breastfeeding durations shorter than 1 month as "no breastfeeding" in our metaanalyses.
Two investigators assessed the methodological quality of all eligible studies by using criteria developed by the U.S. Preventive Services Task Force.87 We assigned each article a quality rating of "good," "fair," or "poor." The criteria for quality assessment of primary studies included randomization techniques, allocation concealment, clear definitions of outcomes, intention-to-treat analysis, and statistical methods. A third investigator reviewed studies for which the first 2 investigators gave discordant quality ratings. We reached final grades for those studies via consensus. We performed subgroup analyses to examine the effects of study quality on the meta-analysis results. We also based our qualitative conclusions on good- or fair-quality studies.
Data Synthesis and Analysis
We calculated the rates of breastfeeding initiation and short-term, intermediate-term, long-term, and prolonged breastfeeding for both the intervention and control groups in each study. We recorded the exclusivity of breastfeeding and did the same calculations for the exclusive breastfeeding rates.
Meta-analysis and Meta-regression
We used the rate ratio (relative risk) as the metric of choice to quantify the effectiveness of each breastfeeding promotion intervention. We used the DerSimonian and Laird model for random-effects meta-analysis88 to obtain summary estimates across studies. We tested for heterogeneity by using the Cochrane Q test, which follows a chi-square distribution to make inferences about the null hypothesis of homogeneity (considered significant at P < 0.100) and quantified its extent with I2.89,90 The I2 statistic ranges between 0% and 100% and quantifies the proportion of between-study variability that is attributed to heterogeneity rather than chance.
We used random-effects meta-regression (fitted with restricted maximum likelihood) to explore whether the effectiveness of breastfeeding interventions depends on breastfeeding duration, provided that at least 6 studies with relevant information were available.91,92
Subgroup Analyses
We performed subgroup analyses according to various study factors, such as study quality, timing of intervention (prenatal, postpartum, or combined prenatal and postpartum), and different components of breastfeeding interventions. We used a Z test to compare summary estimates between the subgroups.
We used Intercooled Stata, version 8.2 (Stata, College Station, Texas) for all analyses. All P values are 2-tailed and considered significant when less than 0.05 unless otherwise indicated.
Role of the Funding Source
The Agency for Healthcare Research and Quality and the U.S. Preventive Services Task Force helped formulate the initial study questions but did not participate in the literature search, determination of study eligibility criteria, data analysis or interpretation, or preparation of the manuscript.
We identified 4877 abstracts in our search and evaluated a total of 147 full-text articles. Thirty-eight RCTs met our eligibility criteria: 32 parallel RCTs described in 33 publications,93-125 4 clustered RCTs,126-129 and 2 quasi-RCTs described in 3 publications130-132 (Figure 2). Table 3 shows the 36 trials that were conducted in developed countries (Australia, Canada, Denmark, France, Italy, Japan, Netherlands, New Zealand, Scotland, Sweden, Singapore, United Kingdom, and United States). Two trials on BFHI were conducted in developing countries (Brazil and Belarus).
The interventions included system-level breastfeeding support (such as BFHI and training of health professionals), formal breastfeeding education, professional support (such as from lactation consultants, midwives, nurses, physicians, or other health professionals), lay support (such as peer support or counseling), motivational interviews, delayed or discouraged pacifier use, and skin-to-skin contact. Several components were often combined into a single, multifaceted breastfeeding intervention.
Eleven trials (29%) were of good quality, 14 trials (37%) were of fair quality, and 13 trials (34%) were of poor quality. The Appendix Table describes the criteria of quality assessment used to reach the overall quality rating for each RCT. Table 3 summarizes the study characteristics.
Key Question 1
What are the effects of breastfeeding interventions on child and maternal health outcomes?
The effects of breastfeeding interventions on child health outcomes were reported in 3 RCTs published in 4 articles.93-95,126 One of these RCTs also reported maternal health outcomes. One good-quality study,126 PROBIT (Promotion of Breastfeeding Intervention Trial), was conducted in Belarus, and 2 fair-quality studies93-95 were conducted in low-income populations in the United States. We could not combine the results from these RCTs in a meta-analysis because the interventions were dissimilar.
The PROBIT study was a good-quality, cluster, multicenter RCT involving a total of 17 046 mother-infant pairs from urban and rural areas in Belarus. Infants in the intervention group (a modeled BFHI) had a significant reduction in the risk for 1 or more gastrointestinal infections (adjusted odds ratio, 0.60 [95% CI, 0.40 to 0.91]) and atopic dermatitis (adjusted odds ratio, 0.54 [CI, 0.31 to 0.95]) compared with those in the control group but had no significant reduction in respiratory tract infections.126 The 2 fair-quality RCTs, involving a total of 564 mother-infant pairs in low-income families in the United States, reported discordant results. The major drawbacks of these 2 RCTs were high rates of loss to follow-up or missing breastfeeding data. One study showed no significant differences between the 2 groups (hospital and home visits by 2 study lactation consultants vs. usual care) in the risk for gastrointestinal illnesses, respiratory tract diseases, or otitis media,94,95 whereas the other study found that the risk for 1 or more diarrheal episodes during the study was decreased in the intervention group (home visits by trained breastfeeding peer counselors) compared with the control group (17.5% vs. 37.5%; P = 0.02).93 The latter study also reported that mothers in the intervention group were less likely than those in the control group to have menses return at 3 months (47.6% vs. 66.7%; P = 0.03). Cessation of menstrual periods for the first few postpartum months during exclusive breastfeeding is a normal physiologic process.
Key Question 2
What are the effects of breastfeeding interventions on breastfeeding initiation, duration, and exclusivity?
Effects on Breastfeeding Initiation and Duration
We found substantial heterogeneity across eligible trials in the actual breastfeeding promotion interventions (including many different combinations of "intervention components") and their implementation, timing, and intensity (Table 3). Furthermore, the definition of "usual" or "routine" care varied substantially because of differences in background social support and health care systems in the various countries. The sociodemographic characteristics of the study populations also varied.
As shown in Figure 3, breastfeeding promotion interventions resulted in an increased rate of breastfeeding initiation (rate ratio, 1.04 [CI, 1.00 to 1.08]) and short-term breastfeeding (rate ratio, 1.10 [CI, 1.02 to 1.19]) compared with usual care, with significant statistical heterogeneity in both cases. It is questionable whether these trivial effects have any real-world effect. For short-term exclusive breastfeeding, the relative risk was 1.72 (CI, 1.00 to 2.97), again with evidence of statistical heterogeneity (Figure 4). When we excluded the 2 RCTs from developing countries,98,126 the results for any breastfeeding initiation and short-term breastfeeding were no longer significant. However, intervention effects on short- and long-term exclusive breastfeeding were significant (rate ratios, 1.28 [CI, 1.11 to 1.48] and 1.44 [CI, 1.13 to 1.84], respectively), with evidence for statistically significant heterogeneity for short-term exclusive breastfeeding (I2. 55%; P = 0.006).
Table 4 describes subgroup analyses performed according to the timing of breastfeeding promoting interventions (prenatal, postnatal, and combinations thereof). Overall, the direction of the effects favors breastfeeding promotion interventions over usual care and was statistically significant for some subgroups (Table 4). We found no clear pattern for the outcome of any breastfeeding with respect to intervention timing. However, for short-term exclusive breastfeeding, the summary point estimates of the corresponding rate ratios are larger for the combination of pre- and postnatal interventions (P = 0.01, <em ">Z test).
We performed subgroup analyses on the effects of different components of breastfeeding interventions on breastfeeding initiation, duration, and exclusivity compared with usual care. Again, multiple components were often combined into a single, multifaceted breastfeeding intervention. Our analyses compared only a specific component within a multifaceted intervention with usual care. Indirect comparison of the pooled effect sizes between different intervention components could be misleading, because other components in the intervention and control groups may not be the same across the different subgroups. Overall, we did not find that formal or structured breastfeeding education or individual-level professional support significantly affected the breastfeeding outcomes. We did find that lay support significantly increased the rate of any and exclusive breastfeeding in the short term by 22% (CI, 8% to 48%) and 65% (CI, 3% to 263%), respectively. Meta-regression suggested that larger effects (compared with usual care) were associated with longer duration for any breastfeeding (P = 0.04) (Table 5).
Finally, the summary rate ratios of breastfeeding initiation and duration did not statistically significantly differ across RCTs of different quality grades (data not shown).
Differences in Absolute Breastfeeding Durations
Ten RCTs in 11 publications100,102,105,107,110,112,119,121,125,130,131 reported the differences in the absolute breastfeeding duration between breastfeeding intervention and usual care groups. The follow-up durations ranged from 2 weeks to 1 year. We did not perform meta-analyses because the intervention components and units of analysis for the breastfeeding outcomes varied greatly across these trials. Seven of the 10 RCTs did not show a significant difference in absolute breastfeeding duration between the intervention and control groups. The other 3 RCTs, 2 of good quality and 1 of fair quality, showed that delayed pacifier use (>4 weeks) was more effective than early pacifier use (within 2 to 5 days)102 and system-level professional support105 and postpartum skin-to-skin care107 were more effective than usual care in increasing breastfeeding duration.
Interventions Involving Family Members
We identified 2 poor-quality RCTs involving family members in breastfeeding intervention. These 2 RCTs were graded poor quality because of incomplete reporting of trial protocol (for example, randomization and blinding) and nonrigorous definitions of breastfeeding outcomes. One study compared the effects of breastfeeding classes for expectant fathers to control group classes of baby care and safety on rates of any breastfeeding initiation and any breastfeeding at 2 months.113 This study found that more women whose partners attended the breastfeeding classes initiated breastfeeding than did women whose partners attended the control class (74% vs. 41%; P = 0.02). However, the rate of any breastfeeding at 2 months did not significantly differ between the intervention and control groups. The other study examined the role of a grandmother (maternal mother) or a close female confidante (sister or friend) of the mother's own choice in supporting breastfeeding.122 This study found no significant difference in breastfeeding initiation or duration between the breastfeeding promotion with a female confidante and the routine prenatal care without a female confidante.
Key Question 3
Are there harms from interventions to promote and support breastfeeding?
We did not identify any study specifically designed to examine harms from interventions to promote and support breastfeeding (regardless of design). None of the eligible RCTs reported harms from the breastfeeding interventions.
This systematic review summarizes the effects of primary care-initiated interventions to promote and support breastfeeding with respect to maternal and child health outcomes and breastfeeding outcomes. Although a large number of RCTs have been published since 2001, fewer than one third of them fulfilled most of our quality criteria and another one third had substantial methodological flaws (Appendix Table). We also found great heterogeneity among the actual interventions as well as the background social support and health care systems that constituted usual or routine care across studies. Nonetheless, the RCTs reviewed in this report showed consistent findings. The evidence suggests that breastfeeding interventions can be more effective than usual care in increasing short- and long-term breastfeeding rates. Combined pre- and postnatal interventions and inclusion of layperson support in a multicomponent intervention may be beneficial. Observational data from our previous report4 showed a relationship between breastfeeding and many beneficial child and maternal health outcomes (Table 1). In summary, only a few RCTs directly examined the effectiveness of breastfeeding interventions on child and maternal health outcomes. Thus, our conclusions about the value of breastfeeding interventions on health outcomes are largely based on an indirect chain of evidence.
Our review has several limitations, which stem mainly from methodological shortcomings of the primary studies and the multitude of possible breastfeeding promotion interventions. First, we found substantial clinical and methodological heterogeneity across studies, which make our summary effects difficult to interpret. This variability in interventions, definitions, and outcomes is not surprising. Breastfeeding schedules and habits are determined by cultural norms, personal desires, and a plethora of socioeconomic factors. To the extent possible, we performed subgroup and sensitivity analyses on factors that may explain the observed heterogeneity. Second, trials of breastfeeding interventions included several individual components. It is impossible to reliably distinguish "independent" effects for these components without performing head-to-head comparisons between them because the effects of individual components cannot be considered independent or additive. Finally, we did not use strict criteria to categorize "primary care-initiated" interventions. Whether a study was classified as primary care-initiated was entirely dependent on the clarity of reporting of the individual studies.
We did not find interventions with formal breastfeeding education or individual-level professional support to be effective in increasing the rates of breastfeeding initiation or duration. However, some evidence suggests that interventions with lay support may be effective in increasing the rates of short- and long-term breastfeeding. This conclusion, however, is based on findings from indirect comparisons of different studies. To further understand the role of lay versus professional support in breastfeeding promotion, future studies should directly compare them in the same population.
Only 2 fair-quality RCTs in developed countries directly examined the effects of breastfeeding interventions on child health outcomes. In both trials, the effects of interventions on rates of exclusive breastfeeding matched the corresponding effects on child outcomes. Specifically, 1 RCT reported an increased exclusive breastfeeding rate at 3 months and a lower risk for diarrheal diseases in the breastfeeding intervention group than in the control group.93 The other RCT did not detect a significant difference in the exclusive breastfeeding rate at 3 months and also did not detect a difference in certain infant health outcomes between the intervention and control groups.94,95 One may surmise from the above findings that the rate of exclusive breastfeeding may be an important determinant of certain health outcomes in infants. It is unclear whether differences in definitions of exclusive breastfeeding, health outcomes, and unknown factors that could interact with the intervention could also explain some of the different findings. However, these findings stressed the need to further examine the role of postnatal home support for breastfeeding from trained professionals or peer counselors.
Two good-quality RCTs conducted in developing countries98,126 provided good evidence that the BFHI is effective in increasing exclusive breastfeeding rates, at least up to 6 months after delivery. The PROBIT126 also compared infants in the breastfeeding intervention group with those in the control group and showed a significant reduction in the risk for 1 or more gastrointestinal infections and atopic dermatitis. It is conceivable that a cluster randomized study similar to PROBIT in Belarus could be done in the United States, as the BFHI is not yet widely adopted; only 1.3% of the maternity units in this country are designated as baby-friendly (according to www.babyfriendly.org). Such a study is important to estimate the public health effect in a sociocultural environment that is not as breastfeeding-friendly as the one in Belarus. To assess the effectiveness of the complete BFHI, it is important to implement all 10 steps (Table 2); none of the studies conducted in developed countries did that.
More cluster RCTs with greater methodological rigor are needed to provide an understanding of the effectiveness of various breastfeeding interventions. Cluster RCTs allow random assignment of groups (such as families or primary care practices) rather than individuals. Cluster studies preempt exposures of intended interventions to nontargeted individuals, thus minimizing cross-contamination of interventions between groups. However, cluster RCTs are more complex to design, require more participants to obtain equivalent statistical power, and demand more complex analyses.133 In addition to proper randomization, the quality of the RCTs can be improved with clear and unbiased patient selection criteria, a common definition of exclusive breastfeeding, reliable collection of feeding data, definition of specific and quantifiable clinical outcomes of interest, and blinded assessments of the outcome. Any substantial differences in the degree of breastfeeding between the intervention and control groups as a result of the breastfeeding intervention will provide further opportunity to investigate any disparity in health outcomes between the 2 groups.
Disclaimer: The authors of this manuscript are responsible for its content. Statements in the review should not be construed as endorsement by the Agency for Healthcare Research and Quality.
Grant Support: From the Agency for Healthcare Research and Quality, U.S. Department of Health and Human Services (contract no. 290-02-0022).
Potential Financial Conflicts of Interest: None disclosed.
Requests for Single Reprints: Mei Chung, MPH, Center for Clinical Evidence Synthesis, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box 63, Boston, MA 02111; e-mail, mchung1@tuftsmedicalcenter.org.
Current author addresses are available at www.annals.org.
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[D] Select for Text Description.
Five linked key questions are proposed in the analytic framework:
- Question 1. What are the effects of interventions to promote and support breastfeeding, in terms of short- and long-term child and maternal health outcomes?
In the figure, Question 1 is linked to text that reads "Breastfeeding interventions: Prenatal, Peripartum, Postpartum" and "Child health outcomes and maternal health outcomes." - Question 2. What are the effects of prenatal, peripartum, and postpartum breastfeeding interventions on initiation, duration, and exclusivity of breastfeeding?
In the figure, an arrow from a text box that reads "Pregnant families and new families of term infants" points to Question 2, and another arrow from Question 2 points to text that reads "Breastfeeding, Initiation, Duration, Exclusivity." - Question 3. Are there any harms from interventions to promote and support breastfeeding?
In the figure, an arrow from the text box that reads "Pregnant families and new families of term infants" points to Question 3, and another arrow from Question 3 points to a circle that reads "Harms." - Question 4. What are the benefits and harms of breastfeeding on infants and children in terms of short- (e.g., otitis media, diarrhea) and long-term health outcomes (e.g., types 1 and 2 diabetes)? In the figure, an arrow from the text box that reads "Breastfeeding, Initiation, Duration, Exclusivity" points to Questions 4 and 5, and arrows from Questions 4 and 5 points to text that reads "Child health outcomes and maternal health outcomes" and a circle that reads "Harms."
- Question 5. What are the benefits and harms of breastfeeding on mothers in terms of short- (e.g., postpartum depression, return to prepregnancy weight) and long-term health outcomes (e.g., osteoporosis, breast and ovarian cancer)?In the figure, an arrow from the text box that reads "Breastfeeding, Initiation, Duration, Exclusivity" points to Questions 4 and 5, and arrows from Questions 4 and 5 points to text that reads "Child health outcomes and maternal health outcomes" and a circle that reads "Harms."
Questions 1, 2, 4, and 5 are also linked to a text box at the top of the figure that reads "Health care system influences."
Contextual Questions:
- What are the effects of health care system influences on interventions to promote and support breastfeeding?
- What are other potential benefits and harms related to interventions to promote and support breastfeeding and from breastfeeding itself?
[D] Select for Text Description.
The figure shows the process of selecting studies for review. The text reads:
Citations identified in MEDLINE®, the Cochrane Central Register of Controlled Trials, and CINAHL (n = 4877)
Abstracts failed to meet criteria (n = 4730)
Articles retrieved for full-text review (n = 147)
Articles failed to meet criteria (n = 109)
No outcome of interest: 10
No breastfeeding data: 3
Not population of interest (e.g., infants in neonatal intensive care unit or premature infants): 2
Not RCT: 32
Not in developed country, except for RCTs of Baby-Friendly Hospital Initiative: 29
Review, abstract, commentary, editorial, or thesis: 11
Interventions not specifically targeted to promote or support breastfeeding: 12
;Not relevant: 10
Articles reviewed (n = 38)
Question 1: 2 parallel RCTs,* 1 clustered RCT*
Question 2: 32 parallel RCTs,* 4 clustered RCTS,* 2 quasi-RCTs
Question 3: No study (regardless of design)
RCT = randomized, controlled trial.
* All RCTs for question 1 also included for question 2.
[D] Select for Text Description.
Study, Year (Reference) | Rate Ratio (95% CI) |
Breastfeeding Promotion, n/n |
Control, n/n |
Quality |
---|---|---|---|---|
Initiation | ||||
Graffy et al., 2004123 | 0.99 (0.96-1.02) | 320/336 | 324/336 | Good |
Quinlivan et al., 2003121 | 0.95 (0.78-1.17) | 51/71 | 49/65 | Good |
Anderson et al., 200593 | 1.07 (0.94-1.21) | 57/63 | 61/72 | Fair |
Bonuck et al., 200594 and 200695 | 1.38 (1.22-1.57) | 130/145 | 103/159 | Fair |
Carfoot et al., 200496 | 0.99 (0.93-1.05) | 91/96 | 97/101 | Fair |
Chapman et al., 2004117 | 1.18 (1.03-1.35) | 239/308 | 58/75 | Fair |
Forster et al. B, 2004100 | 1.01 (0.98-1.04) | 296/306 | 297/310 | Fair |
Forster et al. B, 2004100 | 0.99 (0.95-1.02) | 291/308 | 297/310 | Fair |
Gagnon et al., 2002119 | 0.97 (0.94-1.00) | 247/259 | 250/254 | Fair |
Ekström and Nissen, 2006130; Ekström et al., 2006131 | 1.03 (1.00-1.06) | 206/206 | 167/172 | Poor |
Finch and Daniel, 200299 | 1.14 (0.82-1.60) | 15/19 | 20/29 | Poor |
Lavender et al., 2005127 | 1.09 (1.02-1.16) | 517/679 | 463/663 | Poor |
McLeod et al. A, 2004132 | 0.83 (0.61-1.14) | 16/23 | 25/30 | Poor |
McLeod et al. A, 2004132 | 1.06 (0.88-1.28) | 46/52 | 25/30 | Poor |
Winterburn et al., 2003122 | 0.62 (0.31-1.24) | 8/30 | 18/42 | Poor |
Wolfberg et al., 2004113 | 1.82 (1.13-2.93) | 20/27 | 13/32 | Poor |
Kools et al., 2005129 | Excluded | 371/371 | 330/330 | Fair |
Kronborg et al., 2007128 | Excluded | 781/781 | 816/816 | Fair |
Pooled | 1.04 (1.00-1.08) | 3545/3862 | 3413/3826 | - |
Short-term duration | ||||
Graffy et al., 2004123 | 1.02 (0.91-1.15) | 218/336 | 213/336 | Good |
Kramer et al., 2001126 | 1.21 (1.19-1.24) | 6214/8547 | 4737/7895 | Good |
Labarere et al., 2005105 | 1.09 (0.98-1.22) | 100/112 | 93/114 | Good |
Noel-Weiss et al., 2006125 | 1.35 (1.11-1.63) | 39/41 | 36/51 | Good |
Quinlivan et al., 2003121 | 1.03 (0.67-1.59) | 27/71 | 24/65 | Good |
Anderson et al., 200593 | 1.36 (0.92-2.03) | 13/63 | 26/72 | Fair |
Chapman et al., 2004117 | 1.52 (0.99-2.35) | 36/81 | 21/72 | Fair |
Dennis et al., 2002118 | 1.21 (1.04-1.41) | 107/132 | 83/124 | Fair |
Henderson et al., 2001101 | 0.95 (0.78-1.15) | 56/79 | 57/76 | Fair |
Kools et al., 2005129 | 0.85 (0.70-1.05) | 119/371 | 124/330 | Fair |
Mizuno et al., 2004107 | 0.89 (0.68-1.18) | 22/30 | 23/28 | Fair |
McLeod et al. A, 2004132 | 0.85 (0.55-1.29) | 12/20 | 22/31 | Fair |
McLeod et al. A, 2004132 | 1.09 (0.83-1.43) | 37/48 | 22/31 | Fair |
Pugh et al., 2002120 | 1.07 (0.81-1.42) | 18/21 | 16/20 | Poor |
Schlickau and Wilson A, 2005110 | 1.17 (0.26-5.19) | 3/9 | 2/7 | Poor |
Schlickau and Wilson A, 2005110 | 1.94 (0.53-7.20) | 5/9 | 2/7 | Poor |
Winterburn et al., 2003122 | 1.40 (0.30-6.47) | 3/30 | 3/42 | Poor |
Wolfberg et al., 2004113 | 1.79 (0.73-4.36) | 9/26 | 6/31 | Poor |
Pooled | 1.10 (1.02-1.19) | 7056/10 026 | 5510/9332 | - |
Intermediate-term duration | ||||
Graffy et al., 2004123 | 1.09 (0.91-1.30) | 143/310 | 131/310 | Good |
Labarere et al., 2003104 | 0.86 (0.59-1.24) | 32/93 | 39/97 | Good |
Quinlivan et al., 2003121 | 1.05 (0.65-1.69) | 24/71 | 21/65 | Good |
Wallace et al., 2006111 | 0.93 (0.71-1.22) | 64/174 | 66/167 | Good |
Bonuck et al., 200594 and 200695 | 1.36 (1.06-1.74) | 77/145 | 62/159 | Fair |
Carfoot et al., 200597 | 1.40 (0.60-3.28) | 7/13 | 5/13 | Poor |
Muirhead et al., 2006108 | 1.30 (0.77-2.19) | 26/110 | 20/110 | Poor |
Carfoot et al., 200496 | 1.25 (0.43-3.63) | 5/13 | 4/13 | Poor |
Lavender et al., 2005127 | 0.94 (0.77-1.16) | 140/642 | 138/596 | Poor |
McLeod et al. A, 2004132 | 0.77 (0.37-1.57) | 7/19 | 12/25 | Poor |
McLeod et al. A, 2004132 | 0.98 (0.59-1.62) | 22/47 | 12/25 | Poor |
Pooled | 1.05 (0.96-1.15) | 646/1725 | 600/1671 | - |
Long-term duration | ||||
Kramer et al., 2001126 | 1.38 (1.33-1.43) | 4256/8547 | 2850/7895 | Good |
Quinlivan et al., 2003121 | 0.92 (0.50-1.68) | 16/71 | 16/65 | Good |
Chapman et al., 2004117 | 1.24 (0.68-2.26) | 20/77 | 14/67 | Fair |
Di Napoli et al., 2004124 | 1.52 (1.05-2.20) | 57/266 | 39/276 | Fair |
Forster et al. A, 2004100 | 1.01 (0.87-1.17) | 162/297 | 162/299 | Fair |
Forster et al. B, 2004100 | 0.92 (0.79-1.07) | 146/293 | 162/299 | Fair |
Henderson et al., 2001101 | 2.10 (1.09-4.04) | 42/75 | 48/75 | Fair |
Mizuno et al., 2004107 | 0.97 (0.78-1.21) | 18/30 | 8/28 | Fair |
Lavender et al., 2005127 | 0.94 (0.77-1.16) | 140/642 | 138/596 | Poor |
Pugh et al., 2002120 | 1.43 (0.96-2.13) | 18/21 | 12/20 | Poor |
Wilhelm et al., 2006112 | 1.30 (0.63-2.69) | 12/36 | 9/35 | Poor |
Pooled | 1.14 (0.96-1.35) | 4887/10 355 | 3458/9655 | - |
Prolonged duration | ||||
Bonuck et al., 200594 and 200695 | 1.19 (0.72-1.97) | 26/145 | 24/159 | Fair |
Mizuno et al., 2004107 | 2.80 (0.62-12.7) | 6/30 | 2/28 | Fair |
Lavender et al., 2005127 | 0.91 (0.65-1.28) | 60/639 | 61/593 | Poor |
Pooled | 1.06 (0.75-1.48) | 92/814 | 87/780 | - |
[D] Select for Text Description.
Study, Year (Reference) | Rate Ratio (95% CI) |
Breastfeeding Promotion, n/n |
Control, n/n |
Quality |
---|---|---|---|---|
Initiation | ||||
Coutinho et al., 200598 | 1.01 (0.87-1.16) | 113/161 | 118/169 | Good |
Mattar et al. A, 2007114 | 1.06 (0.94-1.18) | 61/67 | 69/80 | Good |
Mattar et al. B, 2007114 | 0.97 (0.84-1.11) | 60/72 | 69/80 | Good |
Anderson et al., 200593 | 1.39 (1.01-1.92) | 39/63 | 32/72 | Fair |
Forster et al. A, 2004100 | 1.00 (0.92-1.08) | 238/306 | 242/310 | Fair |
Forster et al. B, 2004100 | 0.99 (0.91-1.08) | 239/308 | 242/310 | Fair |
Gagnon et al., 2002119 | 1.05 (0.93-1.18) | 183/259 | 171/254 | Fair |
Mizuno et al., 2004107 | 0.97 (0.78-1.21) | 25/30 | 24/28 | Fair |
Su et al. A, 2007116 | 1.08 (0.66-1.76) | 27/138 | 25/138 | Fair |
Su et al. B, 2007116 | 1.48 (0.94-2.33) | 36/134 | 25/138 | Fair |
Finch and Daniel, 200299 | 2.75 (1.09-6.95) | 9/19 | 5/29 | Poor |
McKeever et al., 2002106 | 1.07 (0.93-1.22) | 52/56 | 40/46 | Poor |
Ryser, 2004109 | 4.11 (1.57-10.8) | 14/23 | 4/27 | Poor |
Pooled | 1.04 (0.98-1.11) | 1096/1636 | 1066/1681 | - |
Short-term duration | ||||
Coutinho et al., 200598 | 4.45 (2.74-7.20) | 72/161 | 17/169 | Good |
Graffy et al., 2004123 | 1.20 (0.94-1.53) | 103/336 | 86/336 | Good |
Kramer et al., 2001103 | 1.08 (0.77-1.51) | 46/127 | 44/131 | Good |
Kramer et al., 2001126 | 6.77 (6.20-7.39) | 3701/8547 | 505/7895 | Good |
Labarere et al., 2005105 | 1.17 (1.01-1.34) | 94/112 | 82/114 | Good |
Mattar et al. A, 2007114 | 2.02 (1.16-3.49) | 27/75 | 15/84 | Good |
Mattar et al. B, 2007114 | 1.57 (0.87-2.81) | 21/75 | 15/84 | Good |
Noel-Weiss et al., 2006125 | 1.41 (1.08-1.84) | 34/41 | 30/51 | Good |
Anderson et al., 200593 | 14.86 (2.00-110) | 13/63 | 1/72 | Fair |
Bonuck et al., 200594 and 200695 | 0.84 (0.42-1.67) | 13/145 | 17/159 | Fair |
Dennis et al., 2002118 | 1.41 (1.09-1.83) | 75/132 | 50/124 | Fair |
Kools et al., 2005129 | 0.85 (0.67-1.07) | 99/371 | 104/330 | Fair |
Muirhead et al., 2006108 | 1.44 (0.80-2.57) | 23/110 | 16/110 | Fair |
Su et al. A, 2007116 | 1.92 (1.12-3.30) | 31/127 | 17/134 | Fair |
Su et al. B, 2007116 | 1.87 (1.09-3.24) | 29/122 | 17/134 | Fair |
Moore and Anderson, 2007115 | 1.00 (0.65-1.55) | 8/10 | 8/10 | Poor |
Pugh et al., 2002120 | 1.71 (0.69-4.24) | 9/21 | 5/20 | Poor |
Pooled | 1.72 (1.00-2.97) | 4408/10 585 | 1039/9967 | - |
Intermediate-term duration | ||||
Labarere et al., 2003104 | 0.97 (0.48-1.95) | 13/93 | 14/97 | Good |
Wallace et al., 2006111 | 0.97 (0.35-2.69) | 7/174 | 7/168 | Good |
Muirhead et al., 2006108 | 5.00 (0.24-103) | 2/110 | 0/110 | Fair |
Carfoot et al., 200496 | 1.25 (0.43-3.63) | 5/13 | 4/13 | Poor |
Pooled | 1.07 (0.65-1.77) | 27/390 | 25/388 | - |
Long-term duration | ||||
Coutinho et al., 200598 | 6.00 (2.77-13.00) | 40/161 | 7/169 | Good |
Kramer et al., 2001126 | 13.3 (9.89-17.8) | 675/8547 | 47/7895 | Good |
Mattar et al. A, 2007114 | 2.11 (0.99-4.52) | 16/80 | 9/95 | Good |
Mattar et al. B, 2007114 | 0.95 (0.38-2.35) | 8/89 | 9/95 | Good |
Bonuck et al., 200594 and 200695 | 0.59 (0.24-1.44) | 7/145 | 13/159 | Fair |
Forster et al. A, 2004100 | 1.19 (0.69-2.05) | 26/297 | 22/299 | Fair |
Forster et al. B, 2004100 | 1.16 (0.67-2.01) | 25/293 | 22/299 | Fair |
Kronborg et al., 2007128 | 1.57 (1.06-2.32) | 59/766 | 40/816 | Fair |
Su et al. A, 2007116 | 2.16 (1.10-4.24) | 23/122 | 11/126 | Fair |
Su et al. B, 2007116 | 2.12 (1.07-4.18) | 22/119 | 11/126 | Fair |
Pugh et al., 2002120 | 1.90 (0.55-6.60) | 6/21 | 3/20 | Poor |
Pooled | 2.01 (0.95-4.23) | 907/10 640 | 194/10 099 | - |
Outcomes Analyzed Term infant outcomes |
Breastfeeding Comparisons Analyzed | Results Summary1 |
---|---|---|
Acute otitis media12-16 | Any definition of breastfeeding duration vs. exclusive bottle feeding | Our meta-analysis of 5 cohort studies showed a significant risk reduction (pooled adjusted OR, 0.60 [95% CI, 0.46-0.78]) when any breastfeeding was compared with no breastfeeding. When exclusive breastfeeding for ≥3 mo was compared with exclusive bottle-feeding from 3 studies, the pooled adjusted OR was 0.50 (CI, 0.36-0.70). |
Atopic dermatitis17 | Exclusive breastfeeding for ≥3 mo vs. <3 mo | A previous meta-analysis of 18 cohort studies reported a reduced risk for atopic dermatitis (pooled adjusted OR, 0.58 [CI, 0.41-0.92]) in children with a family history of atopy. |
Gastrointestinal infection18 | Ever vs. never breastfed | A previous meta-analysis of 16 studies reported a reduced risk for nonspecific gastrointestinal infection. The pooled crude OR of 14 cohort studies for the development of gastrointestinal infection was 0.36 (CI, 0.32-0.41). The pooled crude OR of the 2 case-control studies was 0.54 (CI, 0.36-0.80). |
Lower respiratory tract infection19 | Exclusive breastfeeding for ≥4 mo vs. formula feeding | A previous meta-analysis of 7 cohort studies reported a reduced risk for hospitalization secondary to lower respiratory tract infection (pooled adjusted relative risk, 0.28 [CI, 0.14-0.54]) in infants age <1 y. |
Childhood asthma20-23 | Mixed or exclusive breastfeeding for ≥3 mo vs. never breastfed | Our updated meta-analysis of 15 cohort studies (12 studies were identified from a previous meta-analysis) showed a reduced risk for asthma in children age <10 years without a family history of asthma (pooled adjusted OR, 0.73 [CI, 0.59-0.92]) but conflicting results for children with a family history of asthma. |
Cognitive development24-31 | Any definition of breastfeeding duration vs. never breastfed | Eight primary studies published after 2000 qualified for inclusion. Many of these studies controlled for socioeconomic status and maternal education but not specifically for maternal intelligence. In 3 studies of full-term infants that adjusted analyses specifically for maternal intelligence, the results showed little or no evidence for an association between breastfeeding in infancy and cognitive performance in childhood. |
Obesity32,33 | Ever vs. never breastfed | Reported in a previous meta-analysis of 7 cross-sectional and 2 cohort studies, the pooled adjusted OR for being overweight or obese was 0.76 (CI, 0.67-0.86). One previous meta-regression of 52 estimates from 14 studies (various study designs) found that each month of breastfeeding was associated with a 4% reduced risk (pooled unadjusted OR per month of breastfeeding, 0.96 [CI, 0.94-0.98]). |
Risk for cardiovascular diseases34-36 | Breastfed vs. formula-fed | Overall, no definitive conclusion could be drawn: Two previous meta-analyses of a total of 26 primary studies of various study designs found a small reduction of <1.5 mm Hg in systolic and <0.5 mm Hg in diastolic blood pressure among adults. In addition, 1 previous meta-analysis of 4 historical cohorts found little or no difference in all-cause and cardiovascular mortality. |
Type 1 diabetes37-44 | Breastfeeding for ≥3 o vs. <3 mo | Two previous meta-analyses of a total of 17 case-control studies reported risk reduction for type 1 diabetes (pooled ORs, 0.81 [CI, 0.74-0.89] and 0.70 [CI, 0.56-0.87]). Five of 6 new case-control studies published after the meta-analyses reported similar results. |
Type 2 diabetes45 | Ever breastfed vs. formula-fed | A previous meta-analysis of 7 studies (various study designs) showed a reduced risk for type 2 diabetes in later life (pooled adjusted OR, 0.61 [CI, 0.44-0.85]). However, only 3 of the 7 studies provided information on important confounders, such as birthweight, parental diabetes, socioeconomic status, or maternal body size. |
Childhood leukemia46 | Any definition of breastfeeding duration vs. never breastfed | A previous meta-analysis of 14 case-control studies showed a significant reduced risk for acute lymphocytic leukemia with short-term (>6 mo) and long-term (<6 mo) breastfeeding (pooled OR, 0.88 [CI, 0.80-0.96] and 0.76 [CI, 0.68-0.84], respectively). |
Infant mortality47 | Ever vs. never breastfed | One case-control study reported a protective effect of breastfeeding in reducing infant mortality after controlling for some of the potential confounders. However, in subgroup analyses of the study, the only statistically significant association reported was between "never breastfed" and the sudden infant death syndrome or the risk for injury-related deaths. |
The sudden infant death syndrome48-53 | Ever vs. never breastfed | Our meta-analysis of 6 case-control studies showed a reduced risk for the sudden infant death syndrome (pooled crude OR, 0.41 [CI, 0.28-0.58]; pooled adjusted OR, 0.64 [CI, 0.51-0.81]). |
Maternal outcomes | ||
Return to prepregnancy weight54-56 | Any definition of breastfeeding duration | Three cohort studies reported <1-kg weight change from before pregnancy or first trimester to 1- to 2-year postpartum period in mothers who breastfed. These studies also showed that many factors other than breastfeeding had larger effects on weight retention. |
Maternal type 2 diabetes57 | Exclusive and total breastfeeding duration | One longitudinal cohort reported that each year of lifetime exclusive breastfeeding was associated with a hazard ratio for type 2 diabetes of 0.63 (CI, 0.54-0.73), whereas each year of total breastfeeding was associated with a hazard ratio of 0.76 (CI, 0.71-0.81), after controlling for age and parity. |
Osteoporosis58-63 | Lifetime breastfeeding duration | Results from 6 case-control studies in postmenopausal women showed little or no association between lifetime breastfeeding duration and the risk for hip, forearm, or vertebral fractures due to osteoporosis, after controlling for potential confounders. |
Postpartum depression64-69 | A history of short duration of breastfeeding or no breastfeeding | Three of 6 prospective cohort studies found an association between a history of short duration of breastfeeding or no breastfeeding and postpartum depression. None of the studies explicitly screened for depression at baseline before the initiation of breastfeeding or provided detailed data on breastfeeding. Thus, reverse causality is possible. |
Breast cancer70-74 | Lifetime breastfeeding duration | The reduction in breast cancer risk was 4.3% for each year of breastfeeding in 1 previous meta-analysis combining 45 studies published through 2001, and 28% for ≥12 mo of breastfeeding in the other previous meta-analysis combining 23 studies published between 1980 and 1998. Findings from 3 new primary studies concurred with the findings from the earlier meta-analyses. |
Ovarian cancer75-84 | Lifetime breastfeeding duration vs. no breastfeeding | Our meta-analysis of 9 case-control studies showed a reduced risk for ovarian cancer for ever breastfeeding compared with never breastfeeding (pooled adjusted OR, 0.79 [CI, 0.68-0.91]). Subgroup analysis suggested that cumulative breastfeeding duration >12 mo was associated with a reduced risk for ovarian cancer (pooled adjusted OR, 0.72 [CI, 0.54-0.97]). |
OR = odds ratio.
See reference4. Databases searched included MEDLINE, CINAHL, and the Cochrane Database of Systemic Reviews from 1966 to November 2005. Supplemental searches on selected outcomes were conducted through May 2006. Complete search strategy, eligibility criteria, and quality assessments were documented in the methods section (chapter 2) of the evidence report.4
1 The results summarized here were from primary studies and systematic reviews or meta-analyses that were rated quality A or B in the evidence report. The evidence tables are available in the evidence report.4
Intervention | Definition |
---|---|
Formal or structured breastfeeding education | Structured one-to-one or group education sessions or classes (e.g., curriculum or standard agenda) directed at mothers or other family members |
Breastfeeding support Professional support |
System-level: Baby-Friendly Hospital Initiative;1 training of health professionals Individual-level: one-to-one support during hospital stay or outpatient visits; social support (e.g., home visits or telephone support) from health professionals |
Lay support | Peer counseling; social support (e.g., home visits or telephone support) from peers |
Other interventions | Examples include skin-to-skin contact,2 pacifier use, and motivational interviews3 |
1 The Baby-Friendly Hospital Initiative promotes, protects, and supports breastfeeding through The Ten Steps to Successful Breastfeeding for Hospitals. The steps for the United States are: 1) maintain a written breastfeeding policy that is routinely communicated to all health care staff; 2) train all health care staff in skills necessary to implement this policy; 3) inform all pregnant women about the benefits and management of breastfeeding; 4) help mothers initiate breastfeeding within 1 hour of birth; 5) show mothers how to breastfeed and how to maintain lactation, even if they are separated from their infants; 6) give infants no food or drink other than breast milk, unless medically indicated; 7) practice "rooming in" (allowing mothers and infants to remain together 24 hours a day); 8) encourage unrestricted breastfeeding; 9) give no pacifiers or artificial nipples to breastfeeding infants; and 10) foster the establishment of breastfeeding support groups and refer mothers to them on discharge from the hospital or clinic (accessed at www.babyfriendlyusa.org/eng/10steps.html on 3 September 2008).
2 After birth, the newborn is weighed and then immediately placed naked in a prone position between the mother's breasts until the mother chooses to stop the contact or the newborn seems to be ready for feeding.
3 Motivational interviewing with the goal of decreasing ambivalence and resistance toward sustained breastfeeding.
Study, Year (Reference) |
Design | Country | Patients, n | Population Characteristics | Intervention Components | Timing | Control | Outcomes | Qualitya |
---|---|---|---|---|---|---|---|---|---|
Developed countries | |||||||||
Anderson et al., 200593 | Parallel | United States | 182 | Predominantly Latina and low-income, WIC | LS | Prenatal, peripartum, postnatal | BFHIb | Breastfeeding rates, maternal and child health | Fair |
Bonuck et al., 200594 and 200695 | Parallel | United States; | 382 | 56% Medicaid, 39% foreign-born | Ed, PS-IL, provided nursing bras and pump | Prenatal, peripartum, postnatal | Usual prenatal care | Breastfeeding rates, maternal and child health | Fair |
Carfoot et al., 200496,c | Parallel | United Kingdom | 28 | General(sparse demographic data) | Skin-to-skin contact | Postnatal | Routine care | Breastfeeding rates | Poor |
Carfoot et al., 200597 | Parallel | United Kingdom | 201 | General (sparse demographic data) | Skin-to-skin contact | Postnatal | Routine care | Breastfeeding rates | Fair |
Chapman et al., 2004117 | Parallel | United States | 219 | Latino community from Puerto Rico, low-income, BFHI-accredited hospital | LS, provided electric breast pumps | Prenatal, peripartum, postnatal | Routine Ed | Breastfeeding rates | Fair |
Dennis et al., 2002[[118] | Parallel | Canada | 256 | General, well-educated (>60% college education) | LS, telephonebased support | Postnatal | Conventional in-hospital and community postpartum support | Breastfeeding rates | Fair |
Di Napoli et al., 2004124 | Parallel | Italy | 605 | General, well-educated | PS-IL, telephonebased support | Postnatal | No intervention | Breastfeeding rates | Fair |
Ekström and Nissen, 2006130; Ekström et al., 2006131 |
Quasi | Sweden | 378 | Large municipalities, well-educated | PS-SLd | Prenatal, peripartum | Usual care | Breastfeeding rates, absolute breastfeeding durations | Poor |
Finch and Daniel, 200299 | Parallel | United States | 60 | Low-income (urban WIC program), African- American and Hispanic, 25% ≥18 years old | Ed, incentives | Prenatal, peripartum | Usual prenatal care | Breastfeeding rates | Poor |
Forster et al., 2004100 | Parallel | Australia | 981 | Low-income, culturally diverse, BFHI-accredited hospital | Ed e | Prenatal, peripartum | BFHIf | Breastfeeding rates, absolute breastfeeding durations | Fair |
Gagnon et al., 2002119 | Parallel | Canada | 586 | General (living near the urban hospital) | S-ILg, telephonebased support | Postnatal | Usual care in hospital and clinical follow-up | Breastfeeding rates, absolute breastfeeding durations | Fair |
Graffy et al., 2004123 | Parallel | United Kingdom | 720 | General (urban areas) | PS-ILh | Prenatal, peripartum, postnatal | Usual care with no counselor contact | Breastfeeding rates | Good |
Henderson et al., 2001101 | Parallel | Australia | 160 | 2-3-d postpartum stay, well-educated | Ed | Postnatal | Usual postpartum care | Breastfeeding rates | Fair |
Howard et al., 2003102 | Parallel | United States | 700 | Primarily white, well-educated, married, 77% employed | Delayed pacifier use (>4 wk) | Postnatal | Early pacifier use (2-5 d) | Absolute breastfeeding durations | Good |
Kools et al., 2005129 | Cluster ; | Netherlands | 781 | General, well-educated | PS-ILi | Prenatal, peripartum, postnatal | PS plus written material | Breastfeeding rates | Fair |
Kramer et al., 2001103 | Parallel | Canada | 281 | Multicultural (67% Englishspeaking), well-educated, 76% employed | PS-IL, discouraged pacifier use | Postnatal | Pacifier use and PS | Breastfeeding rates | Good |
Kronborg et al., 2007128 | Cluster | Denmark | 1597 | General, BFHI-accredited hospitals | PS-IL | Postnatal | Home visits by health visitors who did not have the training course | Breastfeeding rates | Fair |
Labarere et al., 2003104 | Parallel | France | 212 | Employed, well-educated, prolonged maternity leave | Ed | Postnatal | Usual care in hospital | Breastfeeding rates | Good |
Labarere et al., 2005105 | Parallel | France | 231 | Well-educated, employed, prolonged hospital stay | PS-SLj | Postnatal | Usual care, including LS | Breastfeeding rates, absolute breastfeeding durations | Good |
Lavender et al., 2005127 | Cluster | United Kingdom | 742 | Low-income, lack of social support | PS-SLk | Prenatal, peripartum | Usual prenatal breastfeeding advice | Breastfeeding rates | Poor |
Mattar et al., 2007114 | Parallel | Singapore | 401 | Low-income, less-educated | PS-ILl, Ed materials(book and video) | Prenatal, peripartum | Routine prenatal care | Breastfeeding rates | Good |
McKeever et al., 2002106 | Parallel | Canada | 101 | Metropolitan area, well-educated, about a 48-h postpartum stay | PS-IL | Postnatal | No home visits from lactation nurses | Breastfeeding rates | Poor |
McLeod et al., 2004132 | Quasi | New Zealand | 228 | Maori, smokers | Edm, PS-IL | Prenatal, peripartum, postnatal | Usual care for women who smoked | Breastfeeding rates | Poor |
Mizuno et al., 2004107 | Parallel | Japan | 60 | Postpartum stay ≥4 d, infants not with mothers for 24 h and were fed formula | Skin-to-skin contact | Postnatal | Routine care | Breastfeeding rates, absolute breastfeeding durations | Fair |
Moore and Anderson, 2007115 | Parallel | United States | 21 | General, well-educated | Skin-to-skin contact | Postnatal | Routine care | Breastfeeding rates | Poor |
Muirhead et al., 2006108 | Parallel | Scotland | 225 | Some premature babies (5.3%) and babies in special care, few demographic data on the mothers | LS | Prenatal, peripartum, postnatal | Usual caren | Breastfeeding rates | Fair |
Noel-Weiss et al., 2006125 | Parallel | Canada | 101 | High family income, well-educated, 36% cesarean section, 68% received free formula | Ed | Prenatal,peripartum | Not described (no education) | Breastfeeding rates, absolute breastfeeding durations | Good |
Pugh et al., 2002120 | Parallel | United States | 41 | Low-income, receiving financial medical assistance | PS-IL, LS | Postnatal | Usual care | Breastfeeding rates | Poor |
Quinlivan et al., 2003121 | Parallel | Australia | 136 | Age <18 y | PS-IL | Postnatal | Routine postnatal support | Breastfeeding rates, absolute breastfeeding durations | Good |
Ryser, 2004109 | Parallel | United States | 54 | Low-income (90% eligible for Medicaid) | Ed | Prenatal, peripartum | No intervention | Breastfeeding rates | Poor |
Schlickau and Wilson, 2005110 | Parallel | United States | 30 | Hispanic women, emigrated from Mexico | Ed, commitment to breastfeedo | Prenatal, peripartum | Usual care | Breastfeeding rates, absolute breastfeeding durations | Poor |
Su et al., 2007116 | Parallel | Singapore | 450 | Low-income, less-educated | PS-ILp, printed materials | Prenatal, peripartum, postnatal | Usual care | Breastfeeding rates | Fair |
Wallace et al., 2006111 | Parallel | United Kingdom | 270 | General (not BFHI-accredited hospital) | PS-SLq | Postnatal | Usual postpartum care | Breastfeeding rates | Good |
Wilhelm et al., 2006112 | Parallel | United States | 73 | Rural community | Motivational interview | Postnatal | Usual carer | Breastfeeding rates, absolute breastfeeding durations | Poor |
Winterburn et al., 2003122 | Parallel | United Kingdom | 72 | No data (women in a university hospital) | PS-IL, LSs | Prenatal, peripartum | Routine prenatal care | Breastfeeding rates | Poor |
Wolfberg et al., 2004113 | Parallel | United States | 59 | Low-income, minority | Edt | Prenatal, peripartum | Control education (baby care and safety) | Breastfeeding rates | Poor |
Developing countries (for BFHI only) | |||||||||
Coutinho et al., 200598 | Parallel | Brazil | 350 | Low-income, 24-h hospital stay | PS-ILu | Prenatal, peripartum, postnatal | BFHI (steps 4-9)v | Breastfeeding rates | Good |
Kramer et al., 2001126 | Cluster | Belarus | 17 046 | Prolonged postpartum stay; maternity leave | PS-SLw | Prenatal, peripartum, postnatal | Usual care | Breastfeeding rates, maternal and child health | Good |
BHFI = Baby-Friendly Hospital Initiative; Ed = formal/structured breastfeeding education; LS = lay support; PS = professional support; PS-IL = professional support—individual level; PS-SL = professional support—system level; WIC = Women, Infants, and Children program.
a Go to the Appendix Table for the detailed quality assessment.
b BFHI: breastfeeding warm line (telephone support), conventional breastfeeding education before birth, hands-on breastfeeding assistance, and education from the maternity ward nursing staff.
c Pilot study for reference97.
d Health professionals received a process-oriented program on breastfeeding counseling, including lectures on breastfeeding management and promotion, counseling skills, and personal breastfeeding experiences.
e Two intervention groups: practical skills or attitudes.
f Standard care included formal breastfeeding education, peer support, and postnatal home visits by midwives (BFHI-accredited hospital); the same control group was used to compare both intervention groups (practical skills or attitudes).
g Community follow-up (intervention group): telephone contact 48 hours after delivery and nurse contact in the home on day 3.
h Trained, accredited counselors who visited once before birth, followed by telephone support or home visits if requested.
i Enhanced access to lactation consultants.
j Pediatricians or family physicians who had attended a 5-hour training program (breastfeeding-related knowledge and counseling skills) delivered in 2 parts in 1 month before the beginning of the study.
k Education session (1 day, 9 a.m.-4 p.m.) to help midwives revise their knowledge of lactation management and educate women on basic lactation physiology and effective breastfeeding techniques.
l Two intervention groups: education materials (book and video) and individual counseling (1 session) or education materials (book and video) alone.
m Two intervention groups: breastfeeding support only or breastfeeding support and smoking cessation.
n Usual care included a community midwife for the first 10 days, health visitor after 10 days, breastfeeding support groups, and breastfeeding workshops.
o Two intervention groups: breastfeeding education or breastfeeding education plus commitment to breastfeed.
p Two intervention groups: 1) 1-session video before birth, printed materials, or 15-minute counseling with lactation consultant or 2) counseling sessions after delivery (30 minutes each with lactation consultant) and printed materials.
q Midwives received a 4-hour workshop ("hands-off" approach to breastfeeding: advice about baby initiation of feeding, positioning, and attachment).
r Usual care included a lactation consultant troubleshooting problems during the hospital stay and at each visit by using the American Academy of Pediatrics' 2002 guide to breastfeeding.
s Members of the intervention group were invited to choose a female confidante who could offer support with infant feeding, and the community midwife visited both mother and confidante together at home.
t Breastfeeding classes for expectant fathers taught by peer who was a father.
u BFHI step 10, postnatal home visits by professionals.
v BFHI step 4, skin-to-skin contact in delivery room and helped to breastfeed in delivery room; BFHI step 5, shown how to breastfeed (positioning and attachment); BFHI step 6, infant given only breast milk, given no water/tea, and given no other milk; BFHI step 7, roomed-in; BFHI step 8, advised to breastfeed on demand; BFHI step 9, advised not to give pacifiers and bottles; and BFHI step 10, postnatal home visits by professionals.
w Modeled BFHI.
Intervention Timing | Initiation | Short-Term | Intermediate-Term | Long-Term | ||||
---|---|---|---|---|---|---|---|---|
Studies, n | Rate Ratio (95% CI) | Studies, n | Rate Ratio (95% CI) | Studies, n | Rate Ratio (95% CI) | Studies, n | Rate Ratio (95% CI) | |
Any breastfeeding | ||||||||
Prenatal | 7 | 1.03 (0.98-1.08) | 5 | 1.37 (1.14-1.64) | 1 | 0.98 (0.83-1.15) | 3 | 0.96 (0.87-1.06) |
Postpartum | 3 | 0.97 (0.95-1.00) | 6 | 1.07 (0.98-1.17) | 5 | 0.98 (0.83-1.16) | 6 | 1.25 (0.94-1.66) |
Combined | 6 | 1.09 (0.93-1.27) | 7 | 1.09 (0.95-1.24) | 5 | 1.15 (1.01-1.31) | 2 | 1.38 (1.33-1.43) |
Exclusive breastfeeding | ||||||||
Prenatal | 6 | 1.03 (0.93-1.14) | 3 | 1.52 (1.22-1.90) | 0 | - | 4 | 1.27 (0.92-1.75) |
Postpartum | 3 | 1.05 (0.96-1.13) | 5 | 1.19 (1.07-1.33) | 3 | 1.03 (0.62-1.70) | 2 | 1.60 (1.10-2.32) |
Combined | 4 | 1.18 (0.94-1.47) | 9 | 2.14 (0.95-4.81) | 1 | 5.00 (0.24-102) | 5 | 3.01 (0.93-9.77) |
Specific Intervention Component | Initiation | Short-Term | Intermediate-Term | Long-Term | P Value for Trend | |||||
---|---|---|---|---|---|---|---|---|---|---|
Studies, n | Rate Ratio (95% CI) | Studies, n | Rate Ratio (95% CI) | Studies, n | Rate Ratio (95% CI) | Studies, n | Rate Ratio (95% CI) | |||
Any breastfeeding | ||||||||||
Formal or structured education | 7 | 1.09 (0.98-1.21) | 7 | 1.11 (0.92-1.33) | 4 | 1.04 (0.78-1.39) | 3 | 0.95 (0.86-1.05) | 0.39 | |
System-level professional support | 2 | 1.06 (0.95-1.17) | 3 | 1.07 (0.92-1.26) | 2 | 0.96 (0.84-1.11) | 2 | 1.16 (0.80-1.68) | 0.92 | |
Individual-level professional support | 9 | 1.04 (0.98-1.10) | 9 | 1.06 (0.96-1.17) | 6 | 1.08 (1.95-1.21) | 5 | 1.23 (0.99-1.53) | 0.20 | |
Lay support | 3 | 1.09 (0.92-1.28) | 5 | 1.22 (1.08-1.37) | 1 | 1.30 (0.77-2.19) | 2 | 1.37 (0.98-1.91) | 0.040 | |
Exclusive breastfeeding | ||||||||||
Formal or structured education | 4 | 1.09 (0.90-1.33) | 3 | 1.16 (0.84-1.59) | 1 | 0.97 (0.48-1.95) | 3 | 1.05 (0.74-1.50) | 0.28 | |
System-level professional support | 0 | - | 3 | 1.89 (0.41-8.79) | 1 | 0.97 (0.35-2.69) | 1 | 13.3 (9.89-17.8) | - | |
Individual-level professional support | 7 | 1.04 (0.98-1.10) | 11 | 1.79 (0.88-3.65) | 0 | – | 9 | 2.27 (0.97-5.28) | 0.060 | |
Lay support | 1 | 1.39 (1.01-1.92) | 4 | 1.65 (1.03-2.63) | 1 | 5.00 (0.24-102) | 1 | 1.90 (0.55-6.60) | 0.83 |
* Compared with usual care. Indirect comparison across different subgroups could be misleading.
Study, Year (Reference) |
Design | Method of Randomizationa | Allocation Concealment Adequateb | Intentionto-Treat Analysis | Outcome Assessors Blinded | Loss to Follow-up,%c | Results Adjusted for Confounding | Groups Similar at Baseline | Recruitment Method Appropriated | Statistical Analyses Appropriatee | Overall Quality |
---|---|---|---|---|---|---|---|---|---|---|---|
Developed countries | |||||||||||
Anderson et al., 200593 | Parallel | Assigned by the study field coordinator | No | Yes | Unclear | 15 | None | Yes | Yes | Yes | Fair |
Bonuck et al., 200594 and 200695 | Parallel | Blocked and stratified according to center | Yes | Yes | No | 21 (missing breastfeeding data) | Maternal age, ethnicity, Medicaid status, previous breastfeeding data | Yes | Yes | Yes | Fair |
Carfoot et al., 200496,c | Parallel | Computer-generated randomization list, sequence of envelopes | No | No | No | 7.1 | None | Yes | Yes | No | Poor |
Carfoot et al., 200597 | Parallel | Computer-generated randomization list, sequence of envelopes | No | Yes | No | 3.4 | None | Yes | Yes | Yes | Fair |
Chapman et al., 2004117 | Parallel | Computer software program | Unclear | Yes | No | 25 | None | No | Yes | Yes | Fair |
Dennis et al., 2002118 | Parallel | Random number generated by a statistician | Yes | Unclear | Yes | 1 | None | No | Yes | No | Fair |
Di Napoli et al., 2004124 | Parallel | Unclear | Unclear | Yes | No | 10 | Age, parental education, smoking, parity, participation in breastfeeding course, type of delivery | Yes | Yes | Yes | Fair |
Ekström and Nissen, 2006130; Ekström et al., 2006131 |
Quasi | Randomized pairwise; centers matched in pairs that were similar in size and had similar breastfeeding duration | Yes | No | Unclear | Unclear (can be as high as 33) | None | Yes | Yes | Yes | Poor |
Finch and Daniel, 200299 | Parallel | No | No | No | Unclear | 37 | None | Yes(presumed) | Unclear | Yes | Poor |
Forster et al., 2004100 | Parallel | A computerized system of biased urn randomization | No | No | Unclear | 7 | Income, smoking before pregnancy, education | Yes | Yes | Yes | Fair |
Gagnon et al., 2002119 | Parallel | Block randomization, using computergenerated blocks and stratified by parity | Unclear | Yes | Yes | 15 | None | Yes | Yes | Yes | Fair |
Graffy et al., 2004123 | Parallel | Random permuted blocks by the statistical adviser | Yes | No | Yes | 14 | Decision about the feeding plan | Yes | Yes | Yes | Good |
Henderson et al., 2001101 | Parallel | Computer-generated balanced blocks of 20 | Yes | No | No | 6.3 | None | Yes | Yes | Yes | Fair |
Howard et al., 2003102 | Parallel | Computer-generated balanced blocks of 20 | Yes | Yes | Yes | 2 | All predictors with P ≤ 0.10, including maternal race, previous births, and maternal education | Yes | Yes | Yes | Good |
Kools et al., 2005129 | Cluster | Coin-flip for the center randomization, clusters matched by breastfeeding rates | Yes | Yes | Unclear | 1.0 | Variability of breastfeeding rates among the 10 centers | Yes | No | Yes | Fair |
Kramer et al., 2001103 | Parallel | Computer-generated blocks of 4 | Yes | No | Yes | 8 | Marital status, smoking | Yes | Yes | Yes | Good |
Kronborg et al., 2007128 | Cluster | Computerized | Unclear | Unclear | No | ~1.8 | None | Yes | No | Yes | Fair |
Labarere et al., 2003104 | Parallel | Computer-generated, random numbers in blocks of 8 | Yes | Yes | Yes | 9.5 | None | Yes | Yes | Yes | Good |
Labarere et al., 2005105 | Parallel | Random permuted blocks with a block size of 8 | Yes | Yes | No | 2 | Age, education, white-collar worker, smoking, prenatal class attendance, primiparity, epidural anesthesia, infant birthweight and gestational age, breastfeeding <1 h after delivery, postpartum length of stay >4 d, expected breastfeeding duration >4 mo | Yes | Yes | Yes | Good |
Lavender et al., 2005127 | Cluster | Wards were pair-matched; pairs were randomly allocated to the groups by a midwife, independent of the trial | Yes | Yes | Yes | 5 to 7 | None | Yes | Yes | Yes | Poorf |
Mattar et al., 2007114 | Parallel | Computer-generated list | Yes | Yes | No | 10 | Adjust for multiple comparisons | Yes | Yes | Yes | Good |
McKeever et al., 2002106 | Parallel | Central randomization procedures | Unclear | No | No | 26 | None | Yes | Yes | Yes | Poor |
McLeod et al., 2004132 | Quasi | Random number | No | Yes | No | 60 | Yes (although unclear what variables were adjusted for) | No | Yes | Yes | Poor |
Mizuno et al., 2004107 | Parallel | Unclearg | Unclear | Unclear | No | 10 | Site of enrollment; age of infant at interview; maternal, paternal, and infant characteristics | Yes | Yes | Yes | Fair |
Moore and Anderson, 2007115 | Parallel | Randomization with algorithm to adjust for maternal age, education, marital status, race, smoking, breastfeeding intention, infant sex, and health care provider | No | No | Yes | 5 | None | Yes | Yes | Yes | Poorh |
Muirhead et al., 2006108 | Parallel | In a block of 10, separated for each of 4 strata (primigravidae, previous formula feeder, previously breastfed <6 wk, previously breastfed >6 wk) | Yes | Yes | No | 2.3 | None | Yes | Yes | Yes | Fair |
Noel-Weiss et al., 2006125 | Parallel | Matching the sealed manila envelope with a sealed, sequentially numbered, opaque envelope containing the assignments | Yes | Yes | Yes | 9 | None | Yes | Yes | Yes | Good |
Pugh et al., 2002120 | Parallel | Unclear | Unclear | Yes (no dropout) | Unclear | 0 | Yes (only on matching factors) | Yes | Yes | No | Poor |
Quinlivan et al., 2003121 | Parallel | Computer-generated | Yes | Yes | Unclear | 9.4 | Age, social class, baseline knowledge, factors that were unbalanced between the 2 groups (ethnic origin, social isolation, involvement of the father, homelessness) | Yes(unbalanced factors between the 2 groups were adjusted for) | Yes | Yes | Good |
Ryser, 2004109 | Parallel | Participants select a sealed envelope | Unclear | Yes (no dropout) | No | 0 | No | Yes | Yes | No | Poor |
Schlickau and Wilson, 2005110 | Parallel | Unclear | Unclear | No | Unclear | 17 | None | Unclear | Yes | Yes | Poor |
Su et al., 2007116 | Parallel | Computer | No | Yes | Unclear | 18 | None | Yes | Yes | Yes | Fair |
Wallace et al., 2006111 | Parallel | Telephone-balanced block and computer | Yes | Yes | Yes | 6 | None | Yes | Yes | Yes | Good |
Wilhelm et al., 2006112 | Parallel | Random number | Unclear | No | No | 3 | Baseline breastfeeding self-efficacy, length of time before returning to work | No | No | Yes | Poor |
Winterburn et al., 2003122 | Parallel | Unclear | Unclear | Unclear | Unclear | Unclear | None | Unclear | Yes | Yes | Poor |
Wolfberg et al., 2004113 | Parallel | Unclear | No | No | Unclear | 3 | Breastfed previously, mother was breastfed as an infant, mother plans to breastfeed for first month, mother lives with father; mother's breastfeeding beliefsi | Yes | Yes | Yes | Poor |
Developing countries (for BFHI only) | |||||||||||
Coutinho et al., 200598 | Parallel | Random-number table | Yes | Yes | Yes | 6 | None | Yes | Yes | Yes | Good |
Kramer et al., 2001126 | Cluster | Random-number table | Unclear | Yes | Unclear | 3 | Birthweight, maternal age, previously breastfed infant for ≥3 mo, number of children in household, maternal smoking, family atopic history | Yes | Yes | Yes | Good |
BFHI = Baby-Friendly Hospital Initiative.
a If cluster randomized, controlled trial (RCT), method used to generate the random allocation sequence, including details of any restriction (e.g., blocking, stratification, matching).
b If cluster RCT, method used to implement the random allocation sequence, specifying that allocation was based on clusters rather than individuals and clarifying whether the sequence was concealed until interventions were assigned.
c A good-quality RCT must have < 20% loss to follow-up.
d Appropriate consecutive or randomized.
e If cluster RCT, statistical methods used to compare groups for primary outcome indicating how clustering was taken into account; methods for additional analyses, such as subgroup analyses and adjusted analyses.
f Downgraded to poor quality because only 64.7% of women in intervention attended the workshop.
g Authors stated that it was not possible to randomize all sites because of constraints on willingness of different practices to provide different services and other reasons.
h Downgraded to poor quality because the RCT was underpowered to detect differences.
i Mother's mother thinks that the baby should be breastfed, mother believes that her partner thinks her baby should be breastfed, or father would like the baby to be breastfed.