I was doing some research recently on men's hormones in order to help myself to feel better about my own crazy "monthly" hormones. I had heard about sympathy pain before, but did you know that dads' hormones change during pregnancy, too?
Although men may not be aware of it, they actually undergo hormonal changes as they prepare for fatherhood. Parental behavior appears to depend on sex steroid hormones and prolactin more than on oxytocin and vasopressin. And, there is hormonal data from nonhuman primates and rodents that indicates an association between paternal behavior and the levels of prolactin, estradiol, testosterone, progesterone and cortisol.Levels of cortisol (a stress hormone) tends to spike about four to six weeks after men learn they're going to be fathers, subsiding as the mother's pregnancy progresses, only to peak again during delivery.
About three weeks before the baby arrives, levels of testosterone fall by about 33%. Testosterone is lowest in the days immediately after the birth I wonder if this is truly related to having a baby, or if it's got more to do with the fact that their wives aren't necessarily stimulated to satisfy sexual needs.
At the same time that testosterone is falling, a man's supply of prolactin (a hormone that helps mothers make milk) rises more than 20%. Prolactin in men appears to increasy "sympathy" symptoms and powerful emotional responses to infant stimuli.Male hormones begin to readjust when the baby is 6 weeks old, returning to pre-fatherhood levels by about the time the baby is walking. Hmmmm....6 weeks, there's that magic number again. So, his testosterone drops after his wife isn't really in a position to satisfy his "needs" and starts picking back up after she can.
Scientists can't completely explain why men's hormones fluctuate, sone think it may have to do with their wife's changing pheromones. (I think you know my theory.) Pheromones appeared to work both ways in a study of mice. The males released their own pheromones, which triggered female mice to make more prolactin. Through these unconscious chemical signals mothers and fathers may be spurring more loving, nurturing behavior in each other, increasing the odds their babies will survive.
It is certainly tempting to look to hormones for the biological root of "sympathy" symptoms, but caution is needed. Changes in sexual activity, shifts in the social priorities of the couple, time off work, or the arrival of extended family for a potentially stressful extended visit are obvious candidates of hormone fluxuations. But, for whatever reason, their hormones do fluxuate.