Bisphenol-A exposure during pregnancy and lactation affects maternal behavior in rats.

In mammals, endogenous estrogens are crucial for sexual differentiation during the perinatal period and, in adulthood, for modulating many neuroendocrine and behavioral functions involved in reproduction. In rats, the estrogenic environment during pregnancy and lactation directly affects maternal behavior. Bisphenol-A, an environmental estrogenic-like compound, is able to interact with estrogen receptors in brain areas involved in the activation of reproductive behavior, including maternal behavior. This experiment was aimed to test if the exposure to bisphenol-A (0.040 microg/kg/die, orally) of adult female rats from mating to weaning of the pups, could alter the processes affecting maternal behavior. An appropriate methodology was applied to reveal differences in the behavior of dams directed to male and female pups, testing the dams on post-natal days 3-4 and 8-9. Results show different maternal behavioural patterns towards male and female pups of control mothers, with more ano-genital licking to males than to females. Exposure of mothers to bisphenol-A modified their behavior, reducing specific components of maternal behavior, both active and passive, irrespective of the sex of pups and the period of observation. This experiment shows that maternal behavior is affected by a prolonged exposure to bisphenol-A during pregnancy and lactation, proving an effect on neural circuits in adulthood.