We examined the cross-sectional association of fat distribution with a number of lifestyle and reproductive factors in a random sample of 40,980 postmenopausal women, aged 55 to 69 years. The relationship of weight history with current fat distribution was also explored. Body fat distribution, defined by the ratio of waist-to-hip circumferences (WHR), was most strongly related to body mass index (BMI). WHR was also significantly and negatively associated with physical activity, alcohol consumption, and education, and was significantly positively associated with age, cigarette smoking, and a number of reproductive factors, such as history of infertility, number of live births, age at first live birth, and replacement estrogen use. WHR was not related to past BMIs, after adjusting for current body mass. The best-fit final regression model included (beta +/- s.e.) age (0.003 +/- 0.0001), BMI (0.02 +/- 0.0005), a curvilinear term for BMI (-0.0002 +/- 0.00001), greater than high school education (-0.007 +/- 0.001), cigarette smoking (0.02 +/- 0.001), alcohol drinker (-0.005 +/- 0.001), and number of live births (0.001 +/- 0.0002). The model R2 was 0.21. BMI (R2 = 0.18) and age (R2 = 0.02) accounted for most of the variation in WHR. The association of these lifestyle and reproductive factors with WHR suggests that the deposition of fat in the abdominal versus the gluteal region may be influenced somewhat by factors other than overall adiposity and genetics.