Developmental effects of Di 2 ethylhexylphthalate on ovarian follicles in Wistar rats

In the recent years, concerns have been raised about the incidence of reproductive disorders in human populations. The present study was aimed to determine the effects of maternal exposure to Di 2 ethylhexylphthalate (DEHP) on postnatal development of ovary in Wistar rat offsprings. Forty female Wistar rats were randomly divided in four equal experiment groups; an oil vehicle group and three DEHP-treated groups that received 10, 100 and 500 mg/kg/day Di 2 ethylhexylphthalate by gavage during lactation, respectively. The ovaries of pups were removed at 60 days of postnatal development; their weights recorded and fixed in Bouin’s solution; subsequently 6 µm serial paraffin sections were stained with haematoxylin-eosin; the structural changes of ovarian follicles and corpora lutea were studied. There was no significant difference on mean body weights of offsprings among different groups. However, the mean of ovary weight was decreased significantly (p= 0.037) in 500 mg/kg/day DEHP group. Significant decreases were seen in mean number of primary follicles (p= 0.012) and mean number and diameter of secondary (p= 0.023 and p= 0.012, respectively) and antral (p= 0.025 and p= 0.018, respectively) follicles in high dose DEHP-treated group compared to sham group. Also, mean number of corpora lutea decreased significantly (p= 0.023) at 60 days of age in ovary of offspring in 500 mg/kg/day DEHP group. Moreover, significant increases were seen in number of atretic follicles in moderate (p= 0.012) and high (p= 0.036) DEHP-treated groups. Present study showed that maternal exposure to Di 2 ethylhexylphthalate during lactation affects postnatal development of ovary in offspring Wistar rats and reduces their fertility and reproductive efficiency at puberty.