The Role of Testosterone and Other Hormones in Fatherhood

Why we go from King Kong to Carebear

All fathers have experienced this. Our wives tell us that they are pregnant and our chests puff up. Our ‘soldiers’ were potent. They attacked the wall, broke through, and performed the due task.

So we spend nine months bragging about the incoming progeny. We can lift more pounds, leap higher heights, and hit farther home runs. We get more work done at our jobs and come home to do more.

And we don’t get tired. We make Superman proud.

I miss those days. Sigh.

But it doesn’t last.

The baby shows up and with that comes decreased focus. The super feats decrease and exhaustion sets in. We become a shell of our previous nine-month selves.

What happened?

It used to be chalked up to lack of sleep but it turns out that there’s more to the issue. It’s actually hormonal. Who knew?

There are three hormones that affect men immediately after the birth of their child. The hormones are testosterone, prolactin, and oxytocin. It turns out that men get hormonal too.

Testosterone

According to this study, in male mammals, testosterone stimulates the development and maintenance of traits and behaviors that contribute to male mating effort, including musculature, libido, conspecific aggressivity, and courtship.

In species in which males care for young, testosterone is often high during mating periods but then declines to allow for the caregiving of resulting offspring. This is true for human males.

Now, the study did not account for the fact that the father could be under stress and suffering from lack of sleep which could account for the reduced testosterone. They just noted the lower testosterone levels.

Result

The effect of reduced testosterone is good for parenting. Reduced testosterone changes motivation. Gone is the desire for hunting and in comes the desire to nest.

Prolactin

This is the mommy hormone. The primary responsibility of prolactin is to promote lactation. Mothers have this surging through their bodies in the third trimester of pregnancy. According to this study, expecting dads show a similar surge in prolactin in the days leading up to labour.

Hey, no wonder my mammaries showed an increase in size. I thought it was because I was pumping more weight in my increased testosterone days.

The study showed that lower testosterone and higher prolactin in new fathers are associated with emotional responses when an infant cries.

Result

This is why I bawled my eyes out when my kids were born. Increased prolactin makes men softies and better helpers with the needs of the baby. So wives, if hubby isn’t being helpful, put some prolactin in his meatloaf.

Oxytocin

Oxytocin is often called the “love” hormone due to its role in bonding, empathy, and altruism. It isn’t clear that increased oxytocin levels contribute to good dad behaviour. However, in this study, dads who inhaled oxytocin (therefore, spiking the oxytocin in their bloodstream) engaged more with their babies with longer gazes and increased interaction.

Result

The study does not indicate that there is a natural increase of this hormone in men. It shows the effect of administering the hormone to men. The result is interesting and might be of interest to some of you with distant, non-interacting husbands.

Conclusion

Dads get hormonal too. With the decrease in testosterone and the increase in prolactin, we become more homebodies and less hunter-gatherers.

I’m not sure how long it lasts as the studies don’t indicate that. No doubt it differs from man to man.

Either way, congratulations on your new family member and may you both do your part to raise a wonderful human being.

Now go change that diaper, Dad!