Baicalein, a flavonoid causes prolonged estrus and suppressed fertility output upon prenatal exposure in female mice

Baicalein (BC), a phytoestrogen of the flavonoid family shows beneficiary and adverse effects. Effect of BC on reproduction is still not understood. Reproductive toxic effects on female mice were tested in this study. Inseminated Wistar mice were divided into four groups and administered IP with 30, 60, and 90 mg/Kg body weight of BC on gestation daydays 11, 13, 15, and 17, and controls treated with DMSO. They were allowed to deliver pups and offspring were separated gender-wise on day 21. The stages of the estrus cycle and its lengthlengths of three successive cycles were measured from day 38 of young females. The mature female offspring of at 60 days age havewere cohabited with control males and the female reproductive endpoints and body weights of dams were measured. The BC exposure increased the length of the estrus cycle, especially the metestrus and diestrus phases were prolonged among other phases of the estrus cycle. Recorded significant reduction in the body weights (P<0.05) of prenatally BC exposed dams on 8 and 18 days of gestation. A significant increase in the conception time (P<0.0001), pre (53.42%) and post (8.82%) implantation loss, and resorptions (P=0.055), whereas a significant decrease in the number of implantations and live fetuses (P<0.0001) were found in BC exposed dams in a dose-dependent manner. Prenatal BC exposure prolonged the estrus cycle due to the augmented length of metestrus and diestrus phase, and is reportingreported for the first time. Female fertility output in mice is affected severely by prenatal BC exposure.