How are some men able to lactate when it only occurs during pregnancy?


If I’m not mistaken, lactation only occurs during pregnancy or after birth when the body has the correct hormones. I have never heard of non-pregnant women randomly lactating, yet there are men who do.
I understand men can develop the correct “equipment,” but why would they be experiencing the hormones needed to cause milk production when they aren’t pregnant? Women are capable of pregnancy but their bodies don’t make milk randomly.

In: Biology

Hormones are produced by specific organs (glands) in the body, and if something happens to those organs (benign tumors, surgical operations, poisoning, medication, etc.), then a person’s hormones can go all sorts of wrong, including lactation in men. Add to this that many hormones regulate or influence the output of other hormones, so sending that system into chaos is not particularly hard.

It only happens when the hormone prolactin is present in the body. Females make this hormone when they are pregnant and nursing. In a male, you’d have to use a drug to generate this hormone.

Women and men have all the same chromosomes. (blueprints inside our cells that tell the cells what to do). Except that women have an extra copy of one chromosome (X) and men have different one instead (Y). The Y chromosome is just a tiny addon and the entire body blueprint is stored in the other chromosomes. That means men are technically women with some adjustments done to them while in womb and also during puberty. If those adjustments don’t happen properly the body defaults to female.

Both men and women have mammary glandules, this means both male and female breasts are technically capable of producing milk.

In the case of men, the mammary tissue is very underdeveloped and pretty much non functional, in women it’s much better developed and its functional, what causes this difference is mainly the hormone prolactin. Prolactin activates the mammary glans and women produce more of it during their life, men produce so little the glandules just don’t work and don’t grow… When prolactin increases, the glandule gets more active, this is how women can go from having a developed mammary glans that is not “active” to it produce milk, this happens mainly after childbirth so the baby can feed.

Because this is not an exclusive female trait but rather something that only is induced by the body in females, it can happen that this is induced in a male because of a rise in prolactin…

Think about prolactin as batteries for the breasts, the more you have, the more it works, and men simply don’t produce because they don’t need to make it work

Both biological XY males and biological XX females have all of the sex hormones naturally. It is the balance and interaction of these sex hormones that causes lactation to occur, or not. If the right hormones are present, anyone with mammary glands can lactate, male or female.

Prolactin triggers lactation, and prolactin can become elevated in males or females, even outside of pregnancy. Men are able to lactate because they can make this hormone too.

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