RESUMEN
Morphine is the most important alkaloid of opium that has studied on some body organs. The aim of this study was to determine the effect of morphine on growth and development of ovarian follicles of the ovaries of mouse in different stages of growth. 40 female rats aged three weeks were selected and assigned into two experimental groups, two control and sham groups. For 9 weeks, each rat of experimental group was taken morphine orally with concentrations of 0.1 and 0.0l mg/ml of drinking water. The control group was prescribed only water and sham group was ordered water and sugar. Having anesthetized the rats and removed their ovaries, histological processes were achieved and primary, secondary, mature and atretic follicles were counted and surveyed. The results showed that effects of morphine on primary follicles in different groups were not significant, however, morphine had significant effects on secondary, mature and atretic follicles when compared different groups [P<0.001]. Our findings indicate the effect of morphine on ovulation and function of female genital system