Abstract:

Objective To investigate the effects of maternal exposure to Di (2-ethylhexyl) phthalate (DEHP) during mid- to late pregnancy on pregnancy outcome and offspring development. Methods Fifty pregnant Wistar rats were randomly assigned to 1 mg/kg DEHP treatment group, 250 mg/kg DEHP treatment group, 750 mg/kg DEHP treatment group, 1 000 mg/kg DEHP treatment group and control group (n=10) on pregnancy day 12. Treatment groups were managed with 1 mg/kg, 250 mg/kg, 750 mg/kg and 1 000 mg/kg DEHP through day 17, respectively, and control group were administered with corn oil. The effects of DEHP on behavior, body weight, pregnancy outcome and organ coefficient of pregnant rats, and the effects of DEHP on body weight of offsprings and on vaginal orifice of female offsprings were observed. Results The weight gain of rats in DEHP treatment groups were not affected during exposure period (P>0.05). There was no significant difference in average viable litter size between each treatment group and control group (P>0.05), and no fetal malformation and stillbirth was observed. Twenty-two days after delivery, there was no significant difference in organ coefficient of uterus, ovary, liver, spleen, kidney, thymus, hypothalamus, brain and adrenal gland between treatment groups and control group (P>0.05). There was no significant difference in weight gain of offsprings from day 1 to day 22 after birth between each treatment group and control group (P>0.05). Sixty-six days after birth, 62.5% of female offsprings of 750 mg/kg DEHP treatment group and 81.25% of female offsprings of 1 000 mg/kg DEHP treatment group developed vaginal atresia, while no such abnormality occurred in the other groups. Conclusion Maternal exposure to 750 mg/kg and 1000 mg/kg DEHP during mid- to late pregnancy may not cause significant maternal toxicity, while high incidence of vaginal atresia in adult offsprings can be observed.

Key words: Di (2-ethylhexyl)phthalate, in utero exposure, female, sexual development, offspring, rat