Eleven studies were included in the review (n=5,445 participants): seven RCTs and four observational studies. Six RCTs were judged to be high quality. One RCT and all the observational studies were classified as medium to low quality.
Universal peer support (seven studies, n=4,416): When pooling high-quality RCTs, there was no significant difference in the rate of breastfeeding non-initiation between the antenatal peer support and control groups (RR 0.96, 95% CI 0.76 to 1.22; three RCTs). No significant heterogeneity was observed. Three observational studies showed that women in the intervention group were significantly more likely to initiate breastfeeding than the control group.
Targeted peer support (four studies, n=1,029): When pooling high-quality RCTs, targeted peer support was associated with a significant reduction in breastfeeding non-initiation (RR 0.64, 95% CI 0.41 to 0.99; three RCTs). Significant heterogeneity was found (I2 =69.0%). One observational study showed a significantly higher rate of breastfeeding initiation with targeted peer support compared with the control group.