How do other primates deal with menstruation and in what ways is it different from human menstruation?

Answer 1

It probably seems like menstruation would be a big pain for other primates, right? If you're reading this post and you're a woman, chances are you've had to deal with "Aunt Flow" since your junior high days or even earlier, month after tiresome month, so it makes sense that you'd want to know just how other animals, including our non-human primate cousins cope. After all, it's not like they can just run on down to the pharmacy for supplies. But the thing to remember is that in the past, and even in some other 'natural fertility' groups today, women would typically get married at a much earlier age and spend most of their adult lives either pregnant or breastfeeding, both of which cause what's known as "secondary amenorrhea" (no periods), so they would actually have way fewer periods over the course of their lifetime than we experience. It's the same for other primates (monkeys, apes, lemurs etc.). When a female primate ovulates, odds are she'll also mate with one or more males and become pregnant. Think about it - it's not like non-human primates (in the wild) have access to Birth Control. And, like I mentioned above, the entire time a primate is pregnant and lactating she also is not menstruating since both are metabolically draining on the mother. Infant primates aren't fed jars of mushy baby food or given bottle formula, either, so they pretty much have to rely on mom's milk until they can possibly begin to find food on their own -- especially since food sharing is pretty darn rare in other animals. All of this means that primate babies end up nursing for what would seem to us like a really long period of time. By the time a baby primate is weaning and its mum can ovulate and mate again, odds are she'll also have a line of eager males waiting in the wings to start the whole cycle over again, thus preventing menstruation. When implantation does not occur in a given cycle(recall that the length of a female's cycle varies both between species and also within the members of a given species), however, then the endometrial tissue might be reabsorbed (so there's no external bleeding) or shed (see Strassman, 1996), although few mammals have as much menstrual bleeding as humans. So, as you can see menstruation is not something that would pose a huge problem for most non-human primates because it would be a relatively rare event. Finally, the fact that women in developed countries today menstruate so much is, as you can see, certainly not the "ancestral" pattern, and has been linked to a rise in many types of reproductive cancers.