Abstract
OBJECTIVES: To evaluate motor, cognitive, language, and social-emotional development in breastfed infants whose mothers received the etonogestrel (ENG) implant either immediately postpartum or at 6 weeks postpartum. METHODS: This was a secondary analysis from a randomized controlled trial involving 100 postpartum women and their infants. Postpartum women were block-randomized to receive the ENG implant either within 48 h of delivery (early insertion group, n = 50) or at 6 weeks postpartum (delayed insertion group, n = 50). We focused on infant development assessed at 6-8 months and 12-15 months using the Bayley-III Scales of Infant and Toddler Development (BSID-III). The study was conducted at the University Hospital of Ribeirão Preto Medical School, Brazil. Sociodemographic and clinical characteristics were compared using t tests and χ(2) tests. BSID-III composite scores were analyzed using mixed-effects linear regression. RESULTS: A total of 79 infants completed at least one developmental assessment. No significant differences in baseline sociodemographic and clinical characteristics were observed between groups. At 6-8 months, BSID-III composite scores across all domains were similar between groups. At 12-15 months, the early insertion group had a significantly higher mean motor score compared with the delayed group (108 ± 11 vs. 99 ± 14, P = 0.003), but no significant differences were found in the other domains. CONCLUSION: Immediate postpartum ENG implant insertion did not negatively impact infant development up to 12-15 months. CLINICAL TRIAL REGISTRATION: This study was registered on https://clinicaltrials.gov/, registration number NCT02469454, Link: https://www. CLINICALTRIALS: gov/study/NCT02469454?term=NCT02469454%20&rank=1#study-overview; date of registration: June 9, 2015.