Contraceptive failure rates: new estimates from the 1995 National Survey of Family Growth.

ABSTRACT

PIP: This study estimated method-specific contraceptive failure rates in the US. Estimates were adjusted for underreporting of induced abortion in the main survey. The correction made a sizeable impact, as 25% of the 2,157,473 conceptions due to contraceptive failure were aborted. Data were obtained from the 1995 National Survey of Family Growth and the 1994-95 Abortion Patient Survey. Analysis was based on hazard models for failure in the first 6 and 12 months. Data include 7276 contraceptive use segments. The mean duration was 9.6 months. The pill and condom had the largest shares of use segments. The lowest failure rates were for implants and injectables (2-3%). Failure rates were as follows: oral pills (8%), diaphragm and cervical cap (12%), male condom (14%), periodic abstinence (21%), withdrawal (24%), and spermicides (26%). Failure rates were highest among cohabiting and other unmarried women; women with an annual family income below 200% of the federal poverty level; among Black and Hispanic women; and among adolescents and women in their 20s. The failure rate among low income women declined during 1988-95. Women above the 200% of poverty level had stable rates. Poverty continued to have a negative impact on effective contraceptive use. Four models were used to examine the effects of socioeconomic factors on contraceptive failure.