Abstract:

BACKGROUND: It has important significance to research the changes in ovarian function and structures in women with athletic menstrual cycle irregularities. But at present, reports about ovarian structures in women with athletic menstrual cycle irregularities are less.
OBJECTIVE: To investigate the changes in histomorphology and ultrastructure of ovaries in rats with estrus irregularities resulting from long-term exhaustive swimming and to gain more insight into mechanisms underlying athletic menstrual cycle irregularities.
METHODS: Twenty-four female Sprague-Dawley rats, aged 3 months old, having normal estrus cycles were divided randomly into the control group and the model group with 12 rats in each group. The rats in the model group underwent exhaustive swimming every day until those estrous cycles were disordered. Hematoxylin-eosin staining and transmission electron microscopy were used to investigate the changes in histomorphology and ultrastructure of rat ovaries.
RESULTS AND CONCLUSION: Hematoxylin-eosin staining showed that compared with the control group, typical growing follicles, mature follicles and fresh corpus luteum were relatively reduced, primordial and atretic follicles were relatively increased in the model group. Transmission electron microscope results showed that compared with the control group, less organelle and more lipid droplets both in granulocytes and lutein cells could be observed in the model group. The findings demonstrated that long-term exhaustive sports can inhibit follicular development, maturation, ovulation and corpus luteum formation and result in inhibitory changes of ultrastructure of ovarian cells. This may be one of mechanisms of athletic menstrual cycle irregularities.