About half of all expectant dads gain weight—up to 30 pounds—during their partners’ pregnancies. And that isn’t all. A dad-to-be can expect to be slammed by at least one other pregnancy symptom, like nausea, fatigue, food cravings, odor aversions, mood swings, sleep problems or bouts of bloat.

So, you’re the proud father of a future Baby Boom. Between the morning sickness, stretch marks and so much more, you may ask yourself: Is it normal for a man to gain weight during pregnancy? Yes. About half of all expectant dads gain weight—up to 30 pounds—during their partners’ pregnancies. And that isn’t all. A dad-to-be can expect to be slammed by at least one other pregnancy symptom, like nausea, fatigue, food cravings, odor aversions, mood swings and sleep problems or bouts of bloat.

Yes. First things first: You’re not alone. About half of all expectant dads gain weight during their partners’ pregnancies—up to 30 pounds. And that isn’t all. A dad-to-be can expect to be slammed by at least one other pregnancy symptom, like nausea, fatigue, food cravings, odor aversions, mood swings and even sleep problems or bouts of bloat.

Interestingly, about half of all expectant dad’s gain weight—up to 30 pounds—during their partners’ pregnancies. And that isn’t all. Don’t be surprised when you are slammed by one or more pregnancy symptoms, such as nausea, fatigue, food cravings and bloat.

A dad’s pregnancy symptoms can range from nausea to sore breasts, bloat and more. About half of all expectant dads gain weight during their partners’ pregnancies, so get ready for body changes and some side effects.

Where Do You Gain Weight When Pregnant With A Girl

What should a man expect when he’s expecting? To loosen his belt. About half of all expectant dads gain weight—up to 30 pounds—during their partners’ pregnancies.

And that isn’t all. A dad-to-be can expect to be slammed by at least one other pregnancy symptom, like nausea, fatigue, food cravings, odor aversions, mood swings, sleep problems or bouts of bloat. Symptoms commonly strike in the first trimester, wane in the second and return with a vengeance in the third.

This is not just some trend among modern, metrosexual Mr. Sensitive types. Even in antiquity, men experienced pregnancy symptoms. In the late 19th century, psychologists termed male pregnancy symptoms couvade, from the French word “couver,” meaning “to incubate” or “to brood” like a mother bird.

Freudians attributed couvade to “fetus envy,” but recent science has found that it’s not so cuckoo. It’s a bona-fide biological reaction to incipient fatherhood, long hush-hushed because real men, supposedly, don’t get morning sickness.

A little more than a decade ago, Anne Storey, a psychologist who studies parenting behavior, and Katherine Wynne-Edwards, a zoologist, were so convinced that there is a biological explanation for male pregnancy symptoms that they devised an elaborate experiment. Thirty-one couples, mostly first-time parents, participated. Some had recently had a baby, and others were expecting theirs to arrive soon. The men and women agreed to have their blood drawn before and after they held their baby or a doll. They also completed a checklist: Did they have weight gain, nausea, increased appetite and emotional ups and downs? If their baby cried, how did they feel? How stressed out were they?

An error occurred. Please try again later.Many expectant fathers gain weight and experience a host of other pregnancy symptoms, along with their spouse, thanks to hormonal and other biological changes. Author Jena Pincott explains, in an interview with Kelsey Hubbard.

Ms. Storey and Ms. Wynne-Edwards homed in on a hormone called prolactin. Prolactin levels rise dramatically in women during pregnancy. A Buddhist of a hormone, it slows everything down to a more meditative pace. Under its influence, fats and sugars are metabolized less effectively, which explains the weight gain.

Prolactin also arouses sweet and tender feelings by prompting pleasure hormones known as opioids. In men, it lowers the libido. When high on prolactin, you’re heavy, soft, abundant and more emotionally astute. You’re about to be reincarnated as a parent.

As Ms. Storey and Ms. Wynne-Edwards predicted, many expectant dads had prolactin concentrations that mirrored the soaring levels of their pregnant partners. The more emotionally in sync a couple was at the time of the baby’s birth, the more likely the male’s prolactin level was high. And the more elevated his levels, the more extreme his symptoms—the more weight he put on, the more crippling his nausea, the more finicky he was about food and odors.

For many expectant moms, there is good news in these findings. The fathers with a significantly higher level of prolactin—and the irritating symptoms that go with it—tended to be more attached to their newborns and more responsive to the babies’ demands than were the men with lower levels. Those who experienced couvade were the type who clucked and cooed whenever their babies cried. Fittingly, the testosterone levels of high-prolactin papas also dropped, an average of 30%, after holding a baby—arguably making them less competitive, more compassionate, and less likely to stray from their partners.

This research suggests that men have a built-in mechanism that primes them for fatherhood and family life. From an evolutionary perspective, even the pudge has a purpose. It’s an energy reserve, because parenting is one of life’s most demanding activities.

An evolutionary view of paternity also turns out to be useful for other puzzling questions. Take the long-standing belief that babies look more like their fathers than their mothers. Do they, or don’t they?

Most of us assume they do. One study found that family members around the world are three times more likely to think a newborn resembles the father rather than the mother. But when participants are asked to pair photos of children—as infants, kids and teens—with their biological parents, they fail miserably. Though a given baby may look more like her father than her mother, there is no universal bias.

The bizarre part is that the ruse appears to be subconscious. We actually believe it when we tell a new dad that the baby looks like him. This makes sense from an evolutionary point of view, according to psychologist Paola Bressan. The universal tendency to see paternal resemblance in the baby is a lifesaver for infants because it’s a face-saver for men in the event that they aren’t really the father. If paternity were as obvious as we think it is, the father—and everyone else—would not only be certain when the child is his, but also when she is not his. Given that 3% to 5% of babies (or more) are not biologically related to their presumed dads, this widespread belief in paternal resemblance saves babies from being the victims of furious cuckolds.

But does a man really notice and care if a baby looks like him? Steven Platek, a cognitive neuroscientist, and his colleagues took photos of volunteers and then digitally blended each one’s face with those of babies and children of various ages. Each man was shown several sets of photos, and in each set was a child’s face that was digitally altered to look like his. “Which one of these children would you spend the most time with?” the researchers asked. “Which would you spend the most money on?” Other questions followed.

Without detecting the manipulation, men significantly favored photos of kids that looked like them. The more a child looked like a man, the more the man liked the child. A child’s face had to have a minimum of 25% of a man’s features for him to favor it over others. That’s the equivalent proportion of genes he’d share with nieces, nephews and his own grandchildren.

Men had such a strong bias for self-resemblance that Mr. Platek and his team suspected that there was something unique about how the male brain processes children’s faces. Using functional magnetic resonance imaging, which tracks the brain’s blood flow, they found that a man’s brain is much more active than a woman’s when looking at a child who resembles him, especially in brain regions involved in the inhibition of negative responses. A woman knows that a baby to which she gives birth is hers, but men must be more discerning, and that takes more mental processing.

Yet, when a man embraces fatherhood, his brain begins to look more like the mother’s. A new dad might develop new growth in the prefrontal cortex, the region of the brain associated with long-term planning and execution. His amygdala, which plays a key role in processing emotion, shows the same activation patterns as the mother’s when hearing his newborn cry. Seeing the baby’s grins, gurgles and coos stimulates the release of dopamine in the same reward circuits of the brain as cocaine. He’s hooked.

His hormones show it, too. For at least four to seven weeks after his child’s birth, a father’s prolactin levels are likely to be high and his testosterone levels low. Notably, veteran dads produce even more prolactin than first-timers. Apparently, a man’s body holds a memory of babies past.

With fathers now playing a more active role in child-rearing than they have in generations, there’s something reassuring about the idea that nurture is part of their nature. Fathering is the same as it’s always been—except that it was surely easier for our forefathers on the savannah to burn off their prolactin paunch.

Weight Gain During Pregnancy

Gaining sympathy weight during pregnancy is totally normal. Even Arnold Schwarzenegger gained tons of weight during pregnancy. Granted, that pregnancy was his own. Also, having Danny Devito as his OB didn’t help anything. The point is: even though you’re not carrying Junior, you may well gain weight over the 9-month journey to fatherhood.

This “sympathy weight” isn’t a myth. In fact, a 2009 study found that men reportedly gained an average of 14 pounds during their partner’s pregnancy. Here’s why dudes said they gained pregnancy weight:

• Eating outside the home with pregnant partners more often. (Because it’s not like you’re going to say no to her Buffalo Wild Wings cravings. Or her Cheesecake Factory cravings. Or her Dairy Queen cravings. Or … )
• The explosion of new snack options in the house. (Because you need the ingredients for that peanut-butter-pickle-Dorito-sandwich around if you’re going to make them on demand.)
• An overwhelming desire to make their partners feel better about their own weight. (Because why should she feel like she’s the only one who grunts when she tries to stand up?)
• Being served portion sizes for two, just like her. (Because asking for less would be rude and, let’s face it, you don’t want to be rude when she can be a little … unpredictable.)

Sadly, things don’t get much better after the kid arrives. A 2015 study that followed 10,000 men for 2 decades found that the ones who had children were likely to gain an average of 4 pounds. The single dudes without children? Those jerks lost over a pound, probably because of all the sex they were having.

So, how to fight the prenatal dad bloat? Here are some simple steps to make sure the sympathy stay on your lips and not on your hips:

Get Outside With Her: There are plenty of activities she can do while pregnant that will help keep her own weight gain in healthy parameters. Join her on walks, swims or even low impact weight lifting. Just make sure you know what’s safe. Safe? Walking around and shopping for burpees. Not safe? Running around and doing burpees.

Hit The Yoga Mat: If she’s into doing prenatal yoga, you should be into it too. All of the good things it does for her, including increasing strength, flexibility and lowering stress levels, will help you, too. Plus it’ll burn calories and being surrounded by women in yoga pants is often a good thing.

Turn Your Home Into A Gym: Seriously, gym memberships and 2-hour workouts are so last decade. These days, it’s all about the WODs and 7-Minute Workouts, and HiiTs. And if all those options feel a little bit too much like something gym bros do when they’re not at the gym, then check out Fatherly’s home workout section, where you’ll find everything from turning a playground into a gym to preparing your lower back for kid-carrying duty.

As for the food? Just stop eating so much of it, man. Seriously. That’s it. Besides, those peanut-butter-pickle-Dorito-sandwiches are just nasty. What are you even thinking?