It is no secret that men experience their partner’s pregnancy too. Many men gain weight when expected a baby as they join the mother of their child in “eating for two.” They may only worry about the baby’s room and equipment to satisfy the mom but they are usually involved in the preparations. Most men would say they share in the mother’s hormonal highs and lows for nine-plus months thinking they are merely referring to supporting her during the pregnancy hormonal shifts. However, a surprising new study shows that both first-time parents experience hormonal changes during the pregnancy. Yes, that is right, men have hormonal shifts when expecting a baby too.
Woman’s hormones can be completely out of whack during a pregnancy. But, the new study shows that men expecting a baby experience some hormonal changes, too. Published in the American Journal of Human Biology, the study found observable decreases in the levels of testosterone and estradiol in expectant men, which researchers say indicates that impending fatherhood can cause men’s hormone levels to change.
The researchers looked at prenatal hormonal changes in both parents-to-be when expecting a baby. They examined changes in four hormones in 29 first-time expectant couples. The women were ages 20 to 38 and the men were 21 to 42. The 58 participants were assessed four times during the pregnancy. The tests were at approximately the 12, 20, 28 and 36 week periods of the pregnancy.
Only couples expecting a baby together for the first time were included in the trial (two men had children from a prior relationship, but this was the first with the current partner). None of the participants were smokers, had medical conditions that affect hormones or were taking any hormone-altering medications.
The four hormones examined were testosterone, estradiol, cortisol and progesterone.
- Testosterone is tied with aggression and prenatal care. Women experience increases in it during pregnancy.
- Estradiol is linked to caregiving and bonding in mammals. It has long been know that estradiol increase close to delivery for women. However, the research showed as increase for men too around birth.
- Cortisol is a stress hormone that is none to facilitate maternal affectionate behavior toward infants. Men were shown increasing levels closer to the due date, like the women, probably in preparation for carig for the newborn.
- Progesterone is known to manipulate desire for affiliation or social closeness. It also increases for females prior to birth in women, but the affect of changes noted in men were not clear.
As expected, the 29 women showed large increases during their pregnancies in all four hormones. The prenatal men studied, however, showed significant declines in their levels of estradiol and testosterone. They did not show detectable changes in men’s levels of progesterone or cortisol.
The study’s scientists pointed out that other research has indicated that men’s hormones experience changes once the children are born and they become fathers. However, “our findings suggest that these changes may begin even earlier, during the transition to fatherhood,” noted Dr. Robin Edelstein, who was the lead study author.
“We don’t know exactly why men’s hormones are changing,” Edelstein said. The team theorized that the changes could be related to psychological changes that men experience as they prepare for impending fatherhoods, their romantic relationships change, or even any physical changes that men experience when expecting a baby.
Researchers say additional studies are needed to better understand the hormonal shifts men have when expecting a baby as well as postpartum hormonal shirts. The authors points out that future research is needed to determine whether the changes in the future fathers’ hormones reflect processes are associated with fatherhood specifically or have other possible explanations.
By Dyanne Weiss