A review of the effectiveness of a progestogen-only pill containing norgestrel 75 µg/day

Abstract

Objectives: To review published data on the effectiveness of a progestogen-only pill containing norgestrel 75 µg/day which should be under consideration by the FDA in 2022 for sale over the counter in the US.

Study design: A literature search in MEDLINE, EMBASE, and COCHRANE REVIEWS using specified search terms and adding related cross-references.

Results: We identified a total of thirteen relevant studies of women using norgestrel 75 µg/day. None were reported with the rigor characteristic of trial reporting today. Nevertheless, six studies provided data on 3,184 women who were not breastfeeding, followed for over 35,000 months and reported a range of overall failure rates during typical use of norgestrel 75 µg/day from 0 to 2.4/hundred woman-years giving an aggregate Pearl Index of 2.2. Seven additional studies involved 5,445 women some of whom were breastfeeding for at least part of the period of follow-up. More than 36,000 months of use yielded 12-month life table cumulative pregnancy rates for norgestrel 75 µg/day ranging from 0 to 3.4. We were unable to calculate an aggregate Pearl Index for the breastfeeding studies because of lack of crucial data.

Conclusions: The data support that norgestrel 75 µg/day is highly effective in clinical use, with similar estimates of failure in breastfeeding and non-breastfeeding women, providing support to the case for approval without the need to see a healthcare provider.

Keywords: Effectiveness; Norgestrel; OTC; Oral contraception; Progestogen-only pill.