It used to be that once a woman became pregnant, her husband’s job was basically done. Besides helping her through the pregnancy, as any proper man would, he remained the same physically, emotionally, and biologically. Now, we know things are a little different. Some research has shown men’s hormone levels change with the birth of a baby, but according to a new study from the University of Michigan, these changes may occur before the baby’s even born.
“Our findings suggest these changes may begin… during the transition to fatherhood,” said study author Dr. Robin Edelstein, from the university’s Department of Psychology, in a press release. The study was published in the American Journal of Human Biology.
Edelstein and her team conducted four tests on the saliva of 29 couples expecting their first babies. The tests took place throughout the pregnancy period, at 12, 20, 28, and 36 weeks. The team was specifically looking at levels of testosterone, cortisol (the stress hormone), estradiol (a form of estrogen), and progesterone (another female hormone). They found that as pregnancy progressed, all four hormone levels increased in women, however, in men, both cortisol and progesterone levels remained the same while estradiol and testosterone levels decreased.
“We don’t know yet exactly why men’s hormones are changing,” Edelstein said. “These changes could be a function of physiological changes that men experience as they prepare to become fathers, changes in their romantic relationships, or even physical changes that men experience along with their pregnant partners.”