Timing of contraceptive implantation does not influence breastfeeding practices

Breastfeeding success does not appear to differ between new mothers who receive their etonogestrel contraceptive implant immediately after birth and their counterparts who receive the implant at least 2 weeks postpartum, according to a study.

Researchers enrolled 150 participants who planned to breastfeed and use the etonogestrel implant at 2 university hospitals in the Mountain West in the US. Participants had to be at least 13 years old, have term deliveries, and have no contraindications to implant use.

The participants were randomly assigned to implant placement within 24 hrs (immediate, n=78) or at least 2 weeks postpartum (delayed, n=57). Participant characteristics were collected from medical charts and questionnaires. Participants reported breastfeeding status and implant use via electronic questionnaires at 2, 4, 8, 12, and 24 weeks postpartum.

The modified intention-to-treat population comprised 126 participants, including 69 in the immediate arm and 57 in the delayed arm. The per-protocol population consisted of 115 participants, with 62 in the immediate arm and 53 in the delayed arm. Age, race, and ethnicity, as well as previous breastfeeding experience, delivery mode, and epidural use were similar between the two arms. Participants in the delayed arm reported prior implant use less frequently (29 percent vs 43 percent).

In the per protocol analysis, 77.4 percent of participants in the immediate arm and 81.1 percent in the delayed arm reported any breastfeeding at 8 weeks. The difference in the percentage of patients who reported the outcome was smaller in the modified intention-to-treat analysis: 78.3 percent and 78.9 percent, respectively.

Implant continuation at 24 weeks was slightly higher among participants in the immediate arm vs the delayed arm, at 96 percent vs 85 percent, although the difference was not statistically significant (p=0.08).

Exclusive or any breastfeeding and implant continuation through 24 weeks were similar between the two arms.

These findings provide reassuring evidence on etonogestrel implant initiation for breastfeeding people.