This cross-sectional study reports on the menopausal transition of Mayan women from Yucatan, Mexico. A total of 228 women completed the study, and 118 women were classified by history as postmenopausal; the others were premenopausal. Demographic information, reproductive history, physical examination, hormone concentrations, radial bone density, food samples, and history of physical activity were obtained. The average age at which menopause occurred by history was 44.3 +/- 4.4 years; this is reflected in the distribution of FSH levels by age. None of the women reported symptoms of hot flashes, and none recalled any history of significant symptoms associated with their menopausal transition. Hormone levels were similar to U.S. reference values with elevated FSH (66.6 +/- 29.1 mIU/ml), low estradiol (9.4 +/- 8.3 pg/ml) and estrone (13.3 +/- 7.8 pg/ml), E1 > E2, and normal levels of testosterone and androstenedione. BMD declined with age, and values were lower than reference values for United States women. Clinical evidence of fracture was not detected by history or physical examination even for those who were 20 years postmenopausal. The endocrine characteristics of menopause among Mayan women in Yucatan are similar to hormonal changes reported for women in the United States, but signs, symptoms, and apparent consequences are different in the two populations.