Diagnosis and prevalence of uterine leiomyomata in female chimpanzees (Pan troglodytes).

Uterine leiomyomata are common, affecting 70-80% of women between 30 and 50 years of age. Leiomyomata have been reported for a variety of primate species, although prevalence rates and treatments have not been widely reported. The prevalence, diagnosis, and treatment of uterine leiomyomata in the Alamogordo Primate Facility and the Keeling Center for Comparative Medicine and Research were examined. Uterine leiomyomata were diagnosed in 28.4% of chimpanzees with an average age at diagnosis of 30.4 ± 8.0 years. Advanced age (>30 years) was related to an increase in leiomyomata and use of hormonal contraception was related to a decrease in leiomyomata. As the captive chimpanzee population ages, the incidence of leiomyomata among female chimpanzees will likely increase. The introduction of progesterone-based contraception for nonbreeding research and zoological chimpanzees may reduce the development of leiomyomata. Finally, all chimpanzee facilities should institute aggressive screening programs and carefully consider treatment plans.