Predicting pregnancy from pregnancy intentions: prospective findings from the Central Pennsylvania Womens's Heath Study (CePAWHS).

OBJECTIVE: We examined whether adult women's intention for future pregnancy predicted actual pregnancies occurring in a 2-year follow-up study.
METHODS: Data are from the Central Pennsylvania Women's Health Study population-based longitudinal survey of women ages 18-45 (n = 1,420). The analytic sample consists of 889 nonpregnant women who had reproductive capacity. Intention for future pregnancy was ascertained at baseline, and women were re-interviewed 2 years later to document interval pregnancies. The impact of pregnancy intention on subsequent pregnancy was analyzed using multiple logistic regression adjusting for relevant covariates.
RESULTS: At baseline, 46% of women were considering a future pregnancy. One hundred thirty-seven women became pregnant during the 2-year study; of these pregnancies, 83% were intended (occurring in women considering a future pregnancy at baseline) and 17% were unintended (occurring in women not considering a future pregnancy at baseline). Pregnancies occurred in 28% of women who at baseline were considering future pregnancy and 5% of women not considering pregnancy. In adjusted analysis, baseline pregnancy intention was predictive of with pregnancy occurrence in women ages 25-34 (adjusted odds ratio [OR], 4.19; 95% confidence interval [CI], 2.20-7.97) and ages 35-45 (adjusted OR, 26.89; 95% CI, 9.05-79.93), but not in women ages 18-24.
CONCLUSIONS: In this prospective study, pregnancy intention was strongly associated with pregnancy incidence over a 2-year follow-up period among women ages 25 and older, suggesting that pregnancy intentions could be used to identify women at greater risk of pregnancy. Future investigation is needed to confirm these findings and to explore the reasons why pregnancy intentions were not predictive for women ages 18-24.