In young women initiating subdermal contraceptive implants on any day of the menstrual cycle, the risk of luteal phase pregnancy (LPP) with negative pregnancy testing is low, regardless of menstrual cycle time, contraceptive use, or use of emergency contraception (EC), a recent study found. This was a retrospective cohort of young women receiving contraceptive implants; patients with negative pregnancy tests were eligible for same-day insertion, regardless of cycle day, contraceptive use, or last intercourse. Researchers found:
- Of 3,180 insertions, 1,868 (58.8%) were outside recommended guidelines.
- Women with insertions within guidelines were older and more likely to be white.
- Pregnancy data was documented for 1,726 patients: 660 (50.3%) in the within guidelines groups and 1,066 (57.0%) in the outside guidelines group.
- Rates of LPP were 0.3% in the within guidelines group; 0.9% in the outside guidelines group.
Richards M, Teal SB, Sheeder J. Risk of luteal phase pregnancy with any-cycle-day initiation of subdermal contraceptive implants. Contraception. 2017;95(4):364-370. doi:10.1016/j.contraception.2017.01.010.