The association of reproductive history with all-cause and cardiovascular mortality in older women: the Rancho Bernardo Study

Objective: To examine associations of gravidity and parity with all-cause, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality in postmenopausal women. Design: Prospective cohort study. Setting: Rancho Bernardo, a southern California community. Patient(s): One thousand two hundred ninety-four postmenopausal women ages 50-96 who attended a 1984-87 research clinic visit at which reproductive and medical histories were obtained and who were followed through 2007. Intervention(s): None. Main Outcome Measure(s): All-cause, CVD, CHD, and non-CHD CVD mortality, determined by nosologist-coded death certificates. Result(s): Average baseline age was 70.6 +/- 9.2. Numbers of pregnancies ranged from 0 to 13 (median 2); births ranged from 0 to 11 (median 2). During a median of 19.3 years of follow-up, 707 women (54.6%) died, with 46.5% attributed to CVD, 20.5% to CHD, and 26.0% to non-CHD CVD. Trend analyses showed inverse associations of gravidity with CVD mortality and non-CHD CVD mortality. Women with four or more pregnancies were less likely than nulligravidas to have fatal CVD (hazard ratio [HR] 0.63, 95% confidence interval [CI] 0.40-0.99) and non-CHD CVD (HR 0.48, 95% CI 0.26-0.91) independent of age, years postmenopause, obesity, and HDL. Associations increased after the first decade of follow-up. Parity and gravidity were not associated with overall or CHD mortality. Conclusion(s): High gravidity was associated with reduced CVD and non-CHD CVD mortality in postmenopausal women. Protective associations could reflect biological mechanisms that occur with repeated pregnancy or greater social support related to family size among multiparous women. (Fertil Steril (R) 2012;97:118-24. (C) 2012 by American Society for Reproductive Medicine.)