Estrous Cycle, Fertilility and Fetal Development in Rats with Hyperbilirubinemia

Abstract

Objective: Decreasing in reproductive capacity has been observed in jaundiced female rats. The animals with hyperbilirubinemia present early sexual maturation, late ovulation, reduced number of corpora lutea and precocious vaginal opening. The interaction with toxic agents leads to abnormal development of the embryos. The objective is to investigate the influence of jaundice on estrous cycle, fertility, ovaries and fetus development.Methods: 66 female rats were divided into two groups (n=33): group 1 -ligature of the biliopancreatic duct, group 2 -sham operation. These animals were paired with males. Vaginal smears were collected daily to verify pregnancy and the gestational period. The morphologic aspect of the ovaries and the corpus luteum were studied. The morphology of the fetuses were assessed. Serum bilirubins were recorded. 32 rats of the control group and 11 jaundiced rats became pregnant. Results:The 17 rats with hyperbilirubinemia that did not become pregnant presented involutive corpora lutea and modifications in their estrous cycles, remaining in pro-estrus or estrus. The pregnant rats with hyperbilirubinemia had fetuses with abnormal development. Conclusions:Fertilization occurs in jaundiced rats, but reproductive capacity is reduced, with irregular estrous cycles, involutive corpora lutea and abnormal fetal development.