Here’s an article in The New York Times that caught our eye, “In Study, Fatherhood Leads to Drop in Testosterone.”

Testosterone, that most male of hormones, takes a dive after a man becomes a parent. And the more he gets involved in caring for his children — changing diapers, jiggling the boy or girl on his knee, reading Goodnight Moon for the umpteenth time — the lower his testosterone drops. So says the first large study measuring testosterone levels in men when they were single and childless and several years after they had children. Experts say the research has implications for understanding the biology of fatherhood, hormone roles in men and even health issues like prostate cancer.

Now, what does this mean? A few interesting points:

• “The real take-home message,” said Peter Ellison, a professor of human evolutionary biology at Harvard who was not involved in the study, is that “male parental care is important. It’s important enough that it’s actually shaped the physiology of men.”
• The study, experts say, suggests that men’s bodies evolved hormonal systems that helped them commit to their families once children were born. It also suggests that men’s behavior can affect hormonal signals their bodies send, not just that hormones influence behavior. And, experts say, it underscores that mothers were meant to have child care help.
• Scientists say this suggests a biological trade-off, with high testosterone helping secure a mate, but reduced testosterone better for sustaining family life.

The new testosterone study could offer insight into men’s medical conditions, particularly prostate cancer. Higher lifetime testosterone levels increase the risk of prostate cancer, just as higher estrogen exposure increases risk. Read more…