Abstract
OBJECTIVE: To compare reproductive history and postmenopausal health by birth status (preterm vs. full term) in a U.S. longitudinal study of postmenopausal women. Birth status was examined according to region of residence, household, and neighborhood socioeconomic status (SES). METHODS: In the Women's Health Initiative Observational Study, 2271 women were born prematurely (< 37 weeks). ANOVA and Chi-square determined birth status differences of reproductive history, pregnancy, and postmenopausal health. Odds ratios were calculated using either binary logistic or multinomial logistic regression. SES and U.S. region of residence were examined as potential effect modifiers. RESULTS: Preterm-born women compared to term-born women had higher risk of delivering a premature infant (aOR 1.68, 95% CI [1.46, 1.93]), higher odds of later-age first pregnancy (aOR 1.27 95% CI [1.02, 1.58]), longer duration to become pregnant (> 1 year to pregnancy) (aOR 1.10 95% CI [1.01, 1.21]), more miscarriages (aOR 1.23 95% CI [1.11, 1.37]), and more pregnancy complications including hypertension (aOR 1.58 95% CI (1.13, 2.21)], preeclampsia (aOR 1.64 95% CI [1.24, 2.16]), and gestational diabetes (aOR 1.68 95% CI [1.11, 2.53]). Preterm-born women had higher odds of menopause before age 50 (aOR 1.09 95% CI [1.05, 1.14]). Post-menopause, they had higher rates of diabetes (p = .01), hypertension (p = .01), hysterectomy (p = .045), and higher Charlson Comorbidity Index scores (p = .01). CONCLUSIONS: Preterm-born women had higher reproductive and pregnancy risks which when coupled with early menopause, may indicate a shorter childbearing period than term-born women. Guidelines for integration of preterm history in women's health care across the life course are needed to identify and manage their higher risk.