Fertilization capacity of ovum in mice exposed to tamoxifen during emberyonic development

Tamoxifen is an nonsteroid drug which is used for treatment of breast cancer ‚CNS tumours‚stimulation of ovulation in infertility protocoles. Regarding to the affinity of tamoxifen to estrogen receptors and the possible role of estrogen on follicular differentiation, the aim of the present study is to investigate fertility of the mice that their mother had received tamoxifen during pregnancy. In this study‚ 30 adultfemale mice and 15 adult male mice are used. The mice were mated and the pregnant mice received 100μg/kg tamoxifen on 13th day of pregnancy as IP. The mice in control group only received the solvent. After delivery ‚the female pups were kept under standard condition and reached adulthood. For evalution of fertilitey‚ the mice superovulated using hMG and hCG‚ and the oocytes were collected by flashing. The collected oocytes were transferred to culture medium and sperms were added. 48 hours post insemination the number of fertilized oocytes were determined. The results from IVF showed that the role of fertilization in oocytes from experimental group was significently lower than those in control group (P<0/01). The results indicate that maternal exposure to Tamoxifen during pregnancy‚ causes that the involved embryos to show‚ disordered reduced fertility‚ after reaching adulthood.