Objective: To evaluate lactogenesis after early postpartum insertion of the etonogestrel contraceptive implant.
Methods: Healthy peripartum women with healthy, term newborns who desired the etonogestrel implant for contraception were randomly assigned to early (1-3 days) or standard (4-8 weeks) postpartum insertion. The primary outcomes, time to lactogenesis stage II and lactation failure, were documented by a validated measure. The noninferiority margin for the mean difference in time to lactogenesis stage II was defined as 8 additional hours. Secondary data (device continuation and contraceptive use, breast milk analysis, supplementation rates, side effects, and bleeding patterns) were collected at periodic intervals for 6 months.
Results: Sixty-nine women were enrolled. Thirty-five were randomly assigned to early insertion and 34 to standard insertion. There were no statistically significant differences between the groups in age, race, parity, mode of delivery, use of anesthesia, or prior breastfeeding experience. Early insertion was demonstrated to be noninferior to standard insertion in time to lactogenesis stage II (early: [mean±standard deviation] 64.3±19.6 hours; standard: 65.2±18.5 hours, mean difference, -1.4 hours, 95% confidence interval [CI] -10.6 to 7.7 hours). Early insertion was also demonstrated to be noninferior to standard insertion in incidence of lactation failure (1/34 [3%] in the early insertion group, 0/35 [0%] in the standard insertion group [risk difference, 0.03, 95% CI -0.02 to 0.08]). Use of formula supplementation was not significantly different between the groups. Milk composition at 6 weeks was not significantly different between the groups.
Conclusion: Breastfeeding outcomes were similar in women who underwent early compared with standard postpartum insertion of the etonogestrel implant.
Clinical trial registration: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00847587.