Background: Breastfeeding practices remain globally suboptimal despite many known maternal and neonatal health benefits and the Baby-Friendly Hospital Initiative as a global effort to support breastfeeding.

Objective: We aimed to evaluate the effects of the implementation of the Baby-Friendly Hospital Initiative for a proportion of mothers who exclusively breastfed during a 6-month period, including breastfeeding problems, and maternal breastfeeding attitudes.

Methods: Using a quasi-experimental non-equivalent two-group design, we recruited two independent samples of postpartum mothers in a maternity hospital to compare the situation before (N = 162) and after (N = 163) the implementation. We measured breastfeeding status and possible breastfeeding problems via text-message questions at 2 weeks, 1, 4 and 6 months after birth. We measured Mothers' attitudes toward breastfeeding at the maternity hospital and 4 months after birth using the Iowa Infant Feeding Attitude Scale.

Results: The implementation of the Baby-Friendly Hospital Initiative had no effect on the proportion of mothers who exclusively breastfed, and we found no significant differences in exclusive breastfeeding at 6 months (41.3 % vs 52.9 %, p =.435). The intervention did not influence the reported number of breastfeeding problems (p =.260) or maternal breastfeeding attitudes (p =.354). More favourable breastfeeding attitudes (p <.001) and less problematic breastfeeding (p <.001) were associated positively with exclusive breastfeeding.

Conclusion: Exclusive breastfeeding rates did not increase after the intervention; however, the rates at baseline were already high. Ensuring the Baby-Friendly Hospital Initiative practices through pre- and postnatal periods and preparing mothers to manage common breastfeeding problems might improve breastfeeding rates. This trial was registered (0307-0041) with ClinicalTrials.gov on 03/03/2017.