METHODS AND FINDINGS: We included all prospective controlled studies (randomised and non-randomised) comparing rooming-in to nursery care that reported full or partial breastfeeding up to six months. We used the 2016 search results of the Cochrane review and updated the search to August 2018 using OVID MEDLINE. Duplicate data extraction and assessment of risk of bias were performed. Meta-analyses were performed using REVMAN 5. The GRADE approach was used to assess quality of evidence. Seven studies were included, five had 24-hour-per-day, one daytime only and one 8-hours-per-day rooming-in. Four studies had at least one additional co-intervention: Differences in delivery room management, and educational packages. All studies contributing to meta-analyses had 24-hour rooming-in. There was no difference in the proportion of infants on full breastfeeding at 3 months (RR 1.14; 95% CI 0.84 to 1.54; very-low-quality evidence), 4 months (RR 0.99; 95% CI 0.73 to 1.33; very-low-quality evidence) and 6 months (RR 0.95; 95% CI 0.57 to 1.58; low-quality evidence). The proportion of infants on partial breastfeeding at 3-4 months was higher with rooming-in (RR 1.31; 95% CI 1.06 to 1.61; very-low-quality evidence).
CONCLUSION: The addition of non-randomised prospective controlled studies to existing evidence did not add further information on the effects of rooming-in on breastfeeding duration but resulted in lower quality of evidence. Uncertainty about the effects of rooming-in on breastfeeding duration remains.