Effect of maternal anastrozole treatment on ovarian follicle development in neonatal mouse: A morphologic study

Introduction: The origin of neonatal oocyte development is unknown. However, estrogen plays an essential role during development of the female reproductive system. Anastrozole is used as both ovulation stimulating and an anticancer drug. The aim of this study was to evaluate the impact of Anastrozole on follicular development and differentiation in mice. Materials and methods: In the present study, 30 adult female and 15 adult male mice were used. Then, two female mice (at their sterous cycle) were kept with one male mouse in a cage for mating. After observing the vaginal plug (considered as first day of pregnancy) female mice were divided into two groups of control and experimental. In the experimental group, on the 14th day of pregnancy the mice received anastrozole (50 mg/Kg, i.p. injection). After delivery 16 pups were selected in each group. Then 2, 4 and 7 day pups were studies for primordial, primary and growing follicles number. Results: According to the morphometric studies, in the 2 day pup, the breakdown was not complete in treatment group. However, the number of primordial, primary and growing follicles of 4 and 7 day pups were not significantly difference in the control and experimental groups. Conclusion: According to the studies, estrogen is necessary for follicular breakdown and maternal anastrozole can reduce the primordial follicles. However, maternal anastrozole and estrogen depression couldn’t effect on the histology of ovarian follicle in neonatal mouse.