Study of How Genetic Differences Affect the Effectiveness of Emergency Contraceptive Ulipristal Acetate in Women Aged 18 to 40

What this Trial Is About

Researchers are studying why some women have a higher risk of emergency contraceptive failure, focusing on the drug ulipristal acetate UPA used to prevent ovulation. The study aims to understand how genetic differences, especially in the cytochrome P450 pathway that breaks down UPA, affect the drugs ability to delay ovulation. This research hopes to improve emergency contraception effectiveness for all individuals. Participants receive a single 30mg oral dose of ulipristal acetate. They are grouped based on whether they have active or inactive CYP3A5 alleles, which influence how their bodies process the drug. The study evaluates pharmacokinetic and pharmacodynamic responses, including how UPA concentration changes and how ovulation is delayed after taking the drug. During the study, women with regular ovulatory cycles are monitored over one menstrual cycle, approximately 30 days. Researchers measure the delay in follicular rupture and UPA concentration up to 5 days after dosing. Participants undergo testing to assess their genetic status and hormone levels. Study visits and assessments track drug metabolism and ovulation timing to understand individual responses.

Disparities in Emergency Contraceptive Metabolism Dictate Efficacy