Immediate postpartum contraceptive implant placement and breastfeeding success in postpartum people at risk for low milk supply: A randomized non-inferiority trial

Abstract

Objectives: Our goal was to measure the impact of postpartum contraceptive implant insertion timing on breastfeeding success and duration in a population at high-risk for low milk supply.

Study design: We conducted a three-armed randomized non-inferiority study of postpartum people who plan to breastfeed and have known risk factors for low milk supply. Participants were randomized to one of three groups for the timing of implant placement: within 30 minutes of placental delivery, 24-72 hours postpartum, or 6+ weeks postpartum. The primary outcome was time to lactogenesis II (LII). Secondary outcomes included duration and exclusivity of breastfeeding and implant satisfaction through 6 months postpartum.

Results: We enrolled 155 participants. Compared to those who received implants 6+ weeks postpartum, those who received it ≤30 minutes postpartum (mean difference: 2.92 hours, 95% CI: -9.26, 15.1, p = 0.64) or 1-3 days postpartum (mean difference: -0.75 hours, 95% CI: -13.02, 11.51, p = 0.90) had similar time to LII. Similar results were observed for intention to treat analysis. Duration and exclusivity of breastfeeding and implant satisfaction were similar among all groups.

Conclusions: Unfortunately, our results did not meet the threshold of non-inferiority because the confidence intervals included the 8 hours non-inferiority margin defined a priori. However, our results indicate similar time to LII between groups. Ultimately, our study suggests that early etonogestrel implant insertion does not affect breastfeeding success among postpartum people at risk for low milk supply.

Implications: Etonogestrel implant insertion can be offered anytime postpartum to meet the needs of postpartum people.

Keywords: Breastfeeding; Contraceptive implant; Lactation; Postpartum.