Different Pearl Indices in studies of hormonal contraceptives in the United States: impact of study population.

OBJECTIVE: To examine the impact of subject characteristics on efficacy as measured by the Pearl Index (PI) in clinical trials and to make study populations similar by matching. METHODS: Our analysis used US data from four large Phase III studies. We compared results from one fertility control patch study with pooled data from three studies with virtually identical design on oral hormonal contraceptives. First, we identified three characteristics that had the most impact on the PI. Second, we used these three variables and matched subjects from the patch study with those from the oral contraceptive (OC) studies. Finally, we calculated the PIs for matched and unmatched subjects from both the patch study and the OC studies. RESULTS: A total of 3706 subjects were included in our analysis. The variables 'Hispanic ethnicity', 'previous pregnancy' and 'previous use of hormonal contraceptives' had the most impact on the PI. The PIs for the matched patch cohort and the matched OC cohort were 2.97 and 2.48, respectively. Those for the unmatched patch cohort and the unmatched OC cohort were 10.17 and 0.90, respectively. CONCLUSION: Subject characteristics strongly influence the PI in clinical studies of hormonal contraceptives. In particular, Hispanic ethnicity, previous pregnancies and no previous use of hormonal contraceptives result in a higher PI. IMPLICATIONS: PIs from different clinical trials cannot be meaningfully compared unless subject characteristics that have most impact on the PI are similar or are made to be similar statistically as we did here by matching.

Peri-abortion contraceptive use in the French islands of Guadeloupe and La Réunion: variation in the management of post-abortion care.

OBJECTIVES: The abortion rate varies greatly within the French overseas territories including the Caribbean island of Guadeloupe and La Réunion in the Indian Ocean. We compare women's contraceptive paths surrounding an abortion in both territories. METHODS: The data for this study are part of a nationally representative survey of women undergoing abortion in France in 2007. The analysis included 1,211 women from Guadeloupe and 1531 from La Réunion. RESULTS: Results show differences in women's use of contraception before the abortion by study location. Women in Guadeloupe were more likely not to have used contraception in the month they conceived (40% vs. 32%, p < 0.0001). Among those using no contraception or less effective contraception before the abortion, 74% in Guadeloupe and 86% in La Réunion received a prescription for a very effective method such as a hormonal method or intrauterine device after the procedure. In both settings, women with no health insurance or a government health plan were 70% less likely to have received a prescription for a very effective method. CONCLUSIONS: While this study shows a significant increase in the prescription of very effective methods, it also indicates the ineffectiveness of the health care system in closing the gap in the pre-abortion contraceptive disparities observed between Guadeloupe and La Réunion.

Communicating contraceptive effectiveness: A randomized controlled trial to inform a World Health Organization family planning handbook.

OBJECTIVE: The objective of the study was to compare 3 different approaches for increasing clients' understanding of contraceptive effectiveness. STUDY DESIGN: We randomized 900 reproductive-age women in India and Jamaica to 1 of 3 charts presenting pregnancy risk. RESULTS: The most important reason for choosing a contraceptive was how well it prevents pregnancy (54%) followed by few side effects (17%). At baseline, knowledge about contraceptive effectiveness was poor. About half knew oral contraceptive pills are more effective than condoms (46%) and intrauterine devices are more effective than injectables (50%). All 3 charts improved knowledge significantly (P < .01) for these 2 questions. No chart improved knowledge better than any other (P > .05). The chart ranking contraceptive methods on a continuum was judged slightly easier to understand than the other 2 charts. CONCLUSION: Only with accurate understanding of pregnancy risk can clients make informed choices. Our results have already informed a global handbook for family planning providers to use the chart ranking contraceptive methods on a continuum.