Secular increases in obesity have been documented in numerous populations. However, little is known about trends in fat distribution. Because men and women with elevated waist-hip ratios (WHR) constitute a high cardiovascular risk group, it is relevant to document secular changes in WHR. This paper compares WHR in three cohorts of women, one cohort recruited in the late 1960s and the others after 12 y and 24 y intervals. In 1968-1969, a randomly selected sample of women aged of 38 y and 50 y, was given anthropometric examinations (n = 761, total). The same measurements were taken on representative cohorts aged 38 y and 50 y in 1980-1981 (n = 677) and 1992-1993 (n = 167). All analyses of trends in WHR as a function of time are age-specific and body mass index (BMI)-adjusted. An interesting feature of this population is that BMI was stable from 1968-1969 to 1992-1993. However, WHR increased significantly in those aged 38 y and 50 y, independent of BMI (P = 0.001, both ages). The source of these changes in WHR was a combination of increasing waist circumferences and decreasing hip circumferences. Skinfold measurements, taken only at the first two examinations, also increased significantly. This female population appears to have experienced some changes in body shape and composition. However, we cannot explain the increasingly centralized fat patterning by changes in BMI, subcutaneous skinfold thickness or those obesity-related aspects of the modern lifestyle that we were able to measure.