Piroxicam and Levonorgestrel Co-treatment for Emergency Contraception

Objective: To compare the percentage of pregnancies prevented by LNG co-administered with piroxicam or placebo for oral emergency contraception (EC) by a randomised controlled trial. Hypothesis to be tested: LNG plus piroxicam has higher percentage of pregnancies prevented compared with LNG plus placebo for oral emergency contraception. Design and subjects: This will be a prospective, randomised placebo-controlled clinical trial. Women attending the Family Planning Association of Hong Kong for oral EC within 72 hours of unprotected sexual intercourse will be recruited. Study instruments: Prospective follow-up of subjects in the clinic for the primary and secondary outcomes. Interventions: Eligible subjects will be randomised to receive one of the two treatment regimens, i.e. Group A: a single dose of LNG 1.5 mg and piroxicam 40 mg, or Group B: a single dose of LNG 1.5mg and placebo under direct supervision. Main outcome measures: Percentage of pregnancies prevented (PPP) is the primary outcome measure. Secondary outcome measures include failure rate, rate of occurrence of side effects and pattern of the menstruation following EC. Data analysis:The percentage of pregnancies prevented, failure rate and rate of occurrence of side effects will be compared between groups using Fisher-Exact test. Continuous variables regarding menstrual pattern between the two groups will be compared by Mann-Whitney U test. Expected results: LNG plus piroxicam has a higher PPP compared to LNG plus placebo.