History and Objectives: Due to wide spread use of xanthenic compounds as flavoring agents in food industries and their application in the pharmaceutical industry, the effect these substances on human has attracted attention of many investigators. However, since little information is available on the effect of Caffeine on endocrine and reproductive system, the present study is designed to elucidate the teratogenic and other effects of Caffeine on adult rate reproductive system and on the histology of embryo during pregnancy.

Materials and Methods: An experimental study on 28 female Wistar rat (Weight 200-240 gr) was carried out. They were divided into 3 control, sham and experimental groups. On the basis of LD50 (185 mg/kg), 60 mg/kg of Caffeine was injected intrapertioneally. Toxic effect of Caffeine on blood samples and reproductive system were determined. Weight, C-R values and developmental defects were studied on the embryo. Statistical ANOVA analysis was performed.

Results: The results indicate that Caffeine reduces ovarian size, follicular atresia, increase size of corpus luteum and increases luteinization of ovaries. In addition Caffeine induces developmental defects in embryo by reduction of C-R value, retarded growth of organs responsible for movement and bulging of brain.

Conclusion: Caffeine induces histologic changes on the reproductive system of adult female rat and her embryo. Further study on the effect of Caffeine in control of reproduction is recommended. In addition, the effect of Caffeine usage by pregnant mother on the well being of embryo and her reproductive system is recommended.