Pregnancy and pregnancy outcomes in a prospective cohort study: Final results from the Nexplanon Observational Risk Assessment Study (NORA)

Objectives: To monitor pregnancy occurrence and outcomes among Nexplanon users in the United States during standard clinical practice.

Study design: The Nexplanon Observational Risk Assessment (NORA) study was a large prospective cohort study conducted in the United States (US). Study participants with a newly inserted Nexplanon implant were recruited by health care professionals (HCPs) who had completed the Nexplanon clinical training. Via a survey, study participants were followed up at 6-month intervals for 36 months and 6 months after implant removal. Reported unintended pregnancies were validated and classified as noninsertion, preinsertion, during-use, or postremoval.

Results: Four hundred and twenty-eight HCPs in 47 states recruited 7364 Nexplanon users. Pregnancies included one noninsertion, eight preinsertion, three during-use, and 14 postremoval pregnancies; of these 26 pregnancies, 22 resulted in the birth of a healthy child, two resulted in an induced abortion, one resulted in a spontaneous abortion, and one resulted in an ectopic pregnancy. Six pregnancies occurred during-use (n = 3) or within 7 days following implant removal (n = 3), yielding a Pearl Index of 0.04 (95% CI, 0.02-0.09).

Conclusions: Nexplanon is an effective contraceptive in real-world users; the Pearl Index was 0.02 (95% CI, 0.00-0.06) for during-use pregnancies, and 0.04 when including pregnancies that occurred within 7 days following implant removal.

Implications: This large real-world-use study indicates that Nexplanon is as effective as shown in the preapproval clinical trials.