The answers involves a little help from his biology!
Testosterone is a major sex hormone and is responsible for sex drive and reproductive growth. It is present in both men and women and impacts sexual development. Because it is higher in men, it is often blamed for men acting out sexually. But here is what you might not know about the role of testosterone and fatherhood.
Researchers at Northwestern University noted that after a man becomes a parent, his testosterone lowers. And the more involved he is in child care, the lower his testosterone drops. Anthropologist Peter Gray at the University of Nevada Las Vegas thinks that parental care can actually shape a man’s physiology. He believes that the lowered testosterone that comes from parenting helps a man cue into his child and less into the cues of other women. The lowering of testosterone may actually help when it comes to keeping your eye on your family and not on your co-worker. Of course, when testosterone levels drop too low, this can become problematic and men need to see their doctors.
But in terms of men, marriage and parenting, testosterone levels dipping a bit may give a little boost to fidelity. Biology matters and actually works to our advantage when it comes to parenting!