Hormonal changes in pregnancy

Men undergo hormonal changes as they prepare for parenthood too, says neuropsychiatrist Dr Louann Brizendine.

Around a month or so after he learns he’s going to be a dad, a man’s levels of the stress hormone cortisol spike – his brain’s way of saying: “We’ve got a situation, you’d better get your arse into gear”. (His cortisol peaks again during labour, but that could be because you’re screaming obscenities at him.)

Many expectant dads do start “nesting”, but don’t expect him to start knitting booties.

“Women see a baby as a soft little creature to dress in soft little clothes; men’s focus is on construction and equipment – a new car, stroller or high chair,” says Dr Brizendine.

By the time you’re almost ready to pop, his levels of testosterone – the stuff that makes him all tough, blokey and randy – will have dropped by around a third. This is nature’s way of ensuring he’s more likely to stick around to help you dodge projectile vomit. Aww.

Weight gain, cravings and nausea

While his testosterone is falling, his levels of prolactin – a hormone that helps new mothers make milk – rises by more than 20 per cent. Research from the University of Toronto in Canada suggests that increased paternal prolactin may be associated with a condition known as couvade syndrome – where men report symptoms that mirror their pregnant partner’s: weight gain, cravings, nausea and even labour pains.

While many believe these symptoms are related to anxiety about the impending birth, others believe it may go deeper. A 2007 study of 282 expectant dads at St George’s University, UK, found that the majority of the men displayed a variety of pregnancy-associated symptoms. Dr Arthur Brennan, who led the study, believes the condition is genuine.

“Some people may perceive this as men trying to get in on the act,” he says. “But the symptoms are involuntary.”

Even your partner’s brain is being rewired. His hearing centres change to put his ears on high alert, so he can hear the sounds of a baby crying that he might not have heard before. All his other senses are heightening too, preparing him for biological and emotional bonding, so by the time he claps eyes on your squirming bundle of joy, he’s primed for love.

In fact, University of Oxford, UK, researchers found that the sight of a baby’s face activates an area of the brain related to parental instinct within a seventh of a second. And by the time he and your baby have had skin-to-skin contact, says Dr Brizendine, an unbreakable bond has been formed. Sweet.