Effects on reproductive development. (A) Day of vaginal opening (DOV), a hallmark of pubertal onset in the female rat, was significantly advanced by EB and all doses of DPN compared to the vehicle treated controls. (B) There was no overall effect of treatment on bodyweight near the time of vaginal opening. (C) By 10 weeks of age, nearly all of the females neonatally administered EB or the 2 mg/kg dose of DPN (HIGH DPN) were acyclic while all of the vehicle control animals (Oil) were cycling normally. By 16 weeks of age, 75% of the MID DPN treated females and 85% of the LOW DPN treated females were acyclic compared to only one of the control females. (Means ± S.E.M., *P ≤ 0.001).