From Toronto at the annual meeting of the Endocrine Society
Men's hormone concentrations shift significantly throughout the course of their wives' pregnancies and after the baby is born, according to a small, new study. While the study's research team didn't monitor parenting behaviors, animal studies indicate that hormones affect a male's willingness to take care of his offspring, says lead researcher Katherine E. Wynne-Edwards of Queen's University in Kingston, Ontario.
Wynne-Edwards found that concentrations of the male sex hormone testosterone in saliva were, on average, significantly lower in 13 first-time, expectant fathers compared with 14 childless guys. Testosterone concentrations began to rise in the dads soon after their wives gave birth, she says, but remained lower than those in the men who did not have children.
More soon-to-be dads had detectable amounts of estrogen, a female sex hormone, in their saliva than did men whose partners were not