Higher incidence of carpal tunnel syndrome in oophorectomized women. To determine whether the hormonal changes of the menopause are related to the onset of carpal tunnel syndrome (CTS), 53 healthy women, younger than 44 years, and subjected to bilateral oophorectomy between 1 and 4 years before the study, were evaluated. Seventy healthy menstruating women matched for age were used as controls. In those complaining of symptoms and presenting signs suggestive of CTS, sensory and motor nerve conduction studies were done. In the oophorectomized group, 17 of 53 (32%) had clinical CTS, while only seven of 70 of the control group (10%) did so (relative risk for the oophorectomized group = 4.25; 95% confidence intervals 1.47 and 12.61). The nerve conduction studies were abnormal in 14 of 16 oophorectomized women (87.5%), and in only one of seven of the control group (14.2%; P less than 0.002). Symptoms tended to be milder in the controls. Symptoms developed in the first year after oophorectomy in 14 of the 17 women with CTS. This suggests that women develop CTS after oophorectomy more frequently than controls. 