"Pregnancy Hormones Leave Lasting Impact on Lab Mouse Brains, Study Finds"

A study on female mice has found that pregnancy alters brain circuits related to parenting behaviors. Two hormones produced during pregnancy, estradiol and progesterone, were found to change brain cells involved in mating and parenting behavior. Estradiol made the brain more responsive to the odors and sounds of baby mice, while progesterone formed new connections in the parenting circuitry, making it more efficient. These findings may help explain postpartum depression and bonding issues in humans, and suggest that hormones also play a role in rewiring the brains of human fathers.