In this two part episode, we review some of the most important clinical pearls in the pharmacotherapy and practice aspects of hormonal contraceptives with a brief focus on the very first FDA approved OTC hormonal contraceptive product (Opill). Key Concepts (Part 1) The effectiveness of contraceptives varies based on “ideal use” (e.g. in a clinical trial with optimal compliance) versus “typical use” (e.g. real-world effectiveness in patients who may sometimes be less adherent than in clinical trials). Oral, patch, and ring-based hormonal contraceptives (combination estrogen-progestin or progestin-only formulations) with “typical” use are about ~90% effective, meaning in one year there are ~10 unplanned pregnancies with these contraceptive options. When using an estrogen-based oral contraceptive, the estrogen dose should be initiated at a low dose (25 mcg or less per day of ethinyl estradiol). The dose of estrogen may need to be increased if breakthrough bleeding occurs in the early/mid cycle despite being on therapy for at least 6 months. Breakthrough bleeding later in the cycle is typically due to an inadequate progestin dose. In general, manufacturers do not provide multiple different formulations with different progestin doses; therefore, if late breakthrough does occur, an alternative formulation with a different progestin should be considered. If a patient misses one dose of a combination oral contraceptive, they should take the missed dose as soon as possible (even taking two doses at once if they remember when the next dose is due). If two or more doses are missed, the package insert should be consulted for instructions – management depends on the timing of the cycle, recency of unprotected sex, and other factors. References CDC Selected Practice Recommendations for Contraceptive Use. 2016. https://www.cdc.gov/mmwr/volumes/65/rr/rr6504a1.htm?s_cid=rr6504a1_w#B-1-1_down CDC Summary Chart of U.S. Medical Eligibility Criteria for Contraceptive Use. 2016. https://www.cdc.gov/reproductivehealth/contraception/mmwr/mec/summary.html