Exclusive breastfeeding is recommended for all infants for the first 6 months of life and benefits both mother and child⁽¹⁾. Women with overweight or obesity and women with gestational diabetes are at-risk groups for poor breastfeeding outcomes^{(Reference Finkelstein, Keely and Feig2,Reference Babendure, Reifsnider and Mendias3)} . We systematically reviewed evidence for the effect of breastfeeding interventions in these groups on any breastfeeding and exclusive breastfeeding as primary outcomes.

We searched Medline, Embase, CINAHL, PsycInfo and Cochrane Library and clinical trial registries for intervention studies to the 1st May 2020. Meta-analysis was performed for timepoints (0–1 month, 1–2 months, 3–4 months and 6+months) using both random and fixed-effects models, where appropriate. Subgroup sensitivity analyses were conducted for exclusive breastfeeding.

Nineteen trials including 2,740 participants, 226 of which were dyads were included. Intervention increased any breastfeeding at ≥6 months [OR 1.43, 95% CI (1.05–1.95)] and women in the intervention group were 90% more likely to exclusively breastfeed at 1–2 weeks [OR 1.9, 95% CI (1.17–3.09)] and more than twice as likely to exclusively breastfeed at 4–6 weeks [OR 2.23, 95% CI (1.27–3.90)] within the sensitivity analysis.

Breastfeeding interventions in women with gestational diabetes or high BMIs may improve exclusive breastfeeding in the early postpartum period and any breastfeeding from 6 months. The number of trials included was limited and further randomised controlled trials with harmonised outcome reporting are needed to confirm the effect of breastfeeding interventions in these at-risk groups.