When a man becomes a dad, his body changes. Hormones fluctuate. Emotions swirl. But it's a major transition he may not even notice.
Playing and interacting with his nieces convinced Andy he wanted to be a father. But when it finally happened, Andy, an executive in Texas, was surprised by how deeply and fundamentally fatherhood changed him. Andy used to be the kind of man who worked hard and played hard. “I worked 80-plus hours a week, and when I wasn’t working, I wanted to eat and drink.” But now? “Going from buying bottle service and hitting steakhouses on weekends to warming up bottles and changing diapers…our lives changed for the best. It’s hard to describe the overwhelming emotion of the moment you become a father,” Andy says. “The first time you get to hold your kid was the best moment of my life. I stayed awake for 36 hours straight because I couldn’t stop watching her and didn’t want to miss anything.”
Andy’s story might be familiar, but what goes on with new dads is profound. When a man becomes a dad, testosterone drops, oxytocin rises, sleep shifts. But that’s just the beginning. All these changes can lead to personality shifts — a rise in patience and empathy, vulnerability, and sadness. Postpartum depression for dads is a common experience. So is emotional maturity, the mellowing out of a man.
Becoming a dad is a metamorphosis. When men become dads they enter a new phase of life, one profoundly different from the last. It’s as if these men were hitting a second puberty. The hormonal shifts are there. So are the emotional shifts. Society sees you differently, too. New dads and teens have a lot in common. This is a parallel that is only surprising in how it does not come up more often.
“I can see how some guys would experience the total upheaval that comes with becoming a dad as a second puberty,” says psychologist Shane Owens, Ph.D. “The most profound change I can think of is the sense that the universe is a lot bigger and beyond your control than you thought it was.”
Second Puberty in Men During Fatherhood: A Time of Transition
Pinning down parallels between new fatherhood and puberty is complicated in part because researchers are rethinking the way puberty should be studied, calling for more diverse subjects and acknowledging the need to consider social identity and personal background, says puberty researcher Jane Mendle, Ph.D., associate professor of human development at Cornell University. In addition, the study of puberty has mostly focused on girls, because menstruation provides a tangible metric in the path to womanhood. Puberty in girls also tends to follow a more linear path, whereas boys’ puberty is more like popcorn, going off in less predictable patterns, she continues. So there has been a missing narrative about boys in puberty research.
“The adaptation of any life transition can be monumental,” Mendle says. “The transition itself is really rapid, and then there’s this aftermath where you’re coming to terms with what does this new stage of life mean? The interesting thing about both puberty and parenthood is that the transition is primarily a biological one, but it has all this social resonance. And it’s the social piece of it is that’s ultimately very important.”
There are emotional and intellectual aspects of puberty, sure, but by definition, puberty is a biological process. It’s the period of sexual maturation, when the body becomes capable of sexual reproduction. In boys, the penis and testicles reach adult size, pubic hair grows, testosterone levels spike and the voice cracks. As Mendle pointed out, these things don’t always happen in the same order.
Intellectual and emotional maturity are different. Maturity doesn’t necessarily ride shotgun with puberty — it’s cruising on a different highway in the brain — and it’s similar for fathers. Not all men feel off-the-charts seismically different the instant they become fathers. How much new fatherhood and puberty will affect men can vary quite a bit, Mendle says.
“To some degree, maturity can be elusive,” Mendle says. “Someone can be physically but not mentally mature and not necessarily emotionally prepared for the changes that are happening to them. People respond to life transitions in an individualized way.”
Brandon Eddy, Ph.D., a professor at the University of Nevada, Las Vegas, agrees that maturity comes in levels and degrees. “We all progress to what we can call ‘adulthood’ in several steps, and research has coined a new term for this: ‘emerging adulthood,’” Eddy says. “We’re not quite a seasoned, veteran adult but we’re not a child anymore, either. I think having a child is another step there.”
Even with family therapy degrees under his belt, Eddy says he felt more mature after child number three than he did after his first.
“A part of that could be wisdom, or it could be that mistakes I made with our first were fewer with the second and third,” he says. “You do feel [an increasing] level of responsibility — it’s not just my life I could potentially mess up, it’s my whole family’s.”
Second Puberty in Men During Fatherhood: A Time of Change
No matter how fatherhood might affect maturity levels, studies suggest new fatherhood causes physiological changes to men, even if they’re unaware of them. After becoming dads, fathers’ testosterone levels drop, the authors of a 2016 study found. A review published last year explored how this drop in testosterone makes sense from an evolutionary standpoint: Men with lower testosterone tend to be less aggressive and more interested in nesting than hunting for mates, says Craig Garfield, M.D., a pediatrician with Northwestern Medicine.
Dads also show spikes in oxytocin — long known to aid in mother-baby bonding — when looking at pictures of kids compared to levels in non-fathers, researchers concluded in a 2014 study. Researchers working to increase fathers’ involvement in neonatal care are trying to build the case that skin to skin contact with their babies produces oxytocin spikes in fathers as well as mothers, Garfield says.
And although not all men gain weight when they become fathers, on average, men gain five pounds after becoming dads, Garfield and his colleagues found.
“I did get fatter,” says Nick, a special education teacher and father of two in New Hampshire. “Having children made the ‘sensual’ world plummet, and I don’t really mean sex specifically, but just that a wide range of pleasant and pleasurable experiences went away. You’re just too busy and tired to do things you took for granted before and that let you experience the world through your body.”
Triple-chocolate cake and gourmet cookies are reliably intense sensory experiences, he says.
Also on the neural front, fathers — non-biological parents included — show the same changes in brain activity that mothers do when caring for their babies, researchers have noted.
“I would be shocked if there were not important neural changes to the brain after fatherhood because the brain is plastic,” Mendle says. “What that means is it changes in response to what we experience, so naturally fatherhood is going to be one of those experiences.”
Research of parenthood, like puberty research, is starting to broaden, acknowledging the growing understanding that some of the changes mothers experience affect fathers and non-biological parents as well. Non-birth parents sometimes feel shut out and less important compared to birth mothers, for example, and they often suffer in silence because they don’t want to complain to Mom, who’s going through her own massive life transition.
After her wife, Kate, gave birth to their son, Harry, “I felt largely unsure of my role,” says Jen, a yoga studio owner in Saint Petersburg, Florida, who says she sees a lot of similarities between her position and that of fathers. “Whereas before, I was the most important person in Kate’s life, afterwards I was not. I was not the most important person in Harry’s life, either, and this hasn’t really changed. I feel like I’m in love with them, and they’re in love with each other.”
Second Puberty in Men During Fatherhood: A Fragile Time for Mental Disorders
Persistent feelings of sadness sometimes blossom into depression, a well-known byproduct of adolescence that also plagues new fathers. Researchers aren’t sure whether depression in new dads is due to hormonal changes or circumstances but suspect it might be both. What is clear at this point is that it happens, Eddy says.
“In our study, we heard from dads who went with their wives to doctor’s appointments and watched her fill out follow-up questions about depression and told us, ‘I’m reading them and can’t help wondering whether someone should be asking me these questions,’” Eddy says. “But society, as a whole, tells fathers that the expectation of them is to be supportive, not to be supported.”
Garfield was one of the authors of a recent call for the American Academy of Pediatrics (AAP) to revise its recommendation to include fathers in perinatal depression screening. That even the AAP didn’t think to consider dads in depression screening illustrates a lack of acceptance that postpartum depression in fathers even happens.
“Men receive a lot of negative messages from people who don’t believe paternal postpartum depression is even a thing, including from a lot of educated people in health care,” says Eddy, whose current study is examining the barriers keeping depressed dads from seeking help. “They hear, ‘You’re not depressed, you just need to grow up,’ or ‘What do you have to be sad about? You didn’t just go through pregnancy.’”
Interesting parallels aside, obviously, new fatherhood isn’t exactly like puberty. Everyone goes through puberty and not everyone will become a father. Testosterone soars in boys during puberty but falls when men become fathers, so in that way it’s the opposite. Although the body changes during puberty, it’s not like most teen boys sprout a dad bod while still in high school.
But teen boys and new fathers typically experience a roller coaster of emotions during the transition, and we need to get better at acknowledging that for the sake of families.
“A father’s mental health has a direct impact on how they parent,” says clinical psychologist Emily Guarnotta, Psy.D. “A father dealing with significant stress, anxiety, depression or other mental health issues is going to have a hard time with some of the fundamentals of parenting, such as expressing empathy and patience.”
Is Fatherhood a Sort of Post-Post Pubescence? Why Labels Matter
In 2018, the Centers for Disease Control first included fathers in its ongoing Pregnancy Risk Assessment Monitoring System. It’s a step in the right direction in understanding the particular challenges of new fatherhood, but it only came about thanks to moms, who have long been the focal point of family studies when it comes to the first year after birth.
Garfield remembers the inclusion of dads was in response to moms asking researchers, Why are the only questions you’re asking about my partner about whether he slapped or kicked me during pregnancy? I couldn’t have gotten through this without him. “All that is to say that we’re just starting to look at these questions about the transition to fatherhood, and we should have answers to some of those questions in the future,” Garfield says.
It’s well acknowledged that moms go through a transition, but that transition is different from men. Their changes are more apparent, for one. There is pregnancy, hormones, physical labor. And for years after, there is an expectation (an unfair one, many moms would point out) of a growth in nurturing attitude. Postpartum depression for women is easily understood. They’re breastfeeding, they’re withdrawing from hormones, their body and mind have gone through so much.
The truth is, dads go through a transition too. One that is perhaps less obvious and difficult to finger. In this way it is like puberty. In many ways it is not.
“To some of my friends and many of the guys in my practice, there was no experience like becoming a dad,” says Shane Owens. “Puberty, while it may have been horrible and amazing at the time, pales in comparison.”
Dr. Brandon Eddy also notes that the comparison isn’t perfect. “I don’t love comparisons, and puberty isn’t a choice, whereas becoming a parent is. [But] both are times of uncertainty and trying to navigate a new situation. It can be a scary time. There’s a lack of information and a lot of mixed messages out there, too, about what does it mean to be a father, a mother, a good parent? Fathers are often embarrassed to talk about it and ask questions.”
Call it what you will, the changes to men after having a kid are very real. The point is not the name, but an acknowledgment that children change both parents in ways that are deep and meaningful. That recognition? Well, it’s a start.
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