Do Animals Go Through Menstrual Cycles Too

What’s the first thing that comes to your mind when you think of menses or monthly periods? Pain, discomfort and frustration, right? Who could think besides women, some other creatures bleed too? As astonishing as it may sound, but some animals bleed just like women do.

img source

A little relevant information about menses, before you proceed with the article, is the covert and overt menses. The cycle of all mammals, in some regards, is the same which means the endometrium thickens for the implantation of the embryo. In case the egg isn’t fertilized, the endometrium lining sheds again. Anyhow, this lining in most mammals is so thin, it reabsorbs into the body completely. This is called covert menstruation. While in other animals, the endometrial lining is relatively thick so a part of it leaves the body through the vagina, which is called overt menstruation. Women around the world get this later type of menstruation as well.
Now let’s have a look at who these animals are and why do they have monthly periods?

1- Monkeys
Being our primate cousins, female monkeys have a lot of similarities with us humans. From the development of their brain to the structure of some of the organs, monkeys surely have a lot in common with us. Another significant thing that relates them to humans is, female monkeys also get the menstrual cycle. While a wide number of African and Asiatic monkeys have covert menstruation, some species of Australian monkeys are known for having covert menstruation.

img source

How female monkeys differ from female humans, however, is the process of menopause as female humans get their menopause in their early 50’s. On the contrary, female chimpanzees, only who survives to 50, still menstruate, ovulate and become pregnant until their death. Their bottoms swell signaling their fertile periods.

2- Dogs
Though all mammals share the same kind of reproductive organs, its function however can be quite different. Whereas fertilization in female human lasts on an average of 28 days, female dogs, on the contrary, lasts an estrous cycle lasts on an average of 180 days.

img source

The estrous cycle in dogs has four major phases. A dog’s vagina discharges blood and other fluids during the first two of these phases but it’s mostly covert. We can call it heat, constituting the first two phases, proestrus and estrus. The first phase, proestrus, varies from 3 to 17 days. The body produces a large quantity of estrogen. Dogs urinate a lot more frequently during proestrus and can have heavy bleeding as well. The second phase estrus, is relatively short part of the cycle, lasting from 4 to 7 days. This is typically when a dog mates and fertilizes.
Apart from dogs, horses and shrew elephants have a menstrual cycle as well.

3- Bats
Scientists have recently discovered a specie of bats with menstrual cycles just like female humans. This finding is published in Biology of Reproduction, a well-reputed journal. It certainly can trigger other scientists to further study bats in order to understand menstrual and other reproductive problems.

img source

Headed by Professor Shuyi Zhang of East China Normal Universit with, a team of Chinese scientists discovered these facts when they observed the bat Leschenault's rosette residing in caves in South Asia.

4- Cats
Not all species of cats go through menses but the queen cats on reaching the age of puberty, which is 6-months on the average. However, the type of menstrual cycle they have does not include vaginal bleeding instead heating.
The heat cycle occurs every two to three weeks and stays from 1 day to 7. Cats can have multiple estrus cycles during the breeding season which varies according to geographic and environmental factors.
When female humans get the menstrual cycle, they become aggressive and hyper agitated. Mood swings are one of the most notable sign. Cats, on the other hand, become very affectionate, even demanding. They start rubbing against people or objects such as furniture constantly demanding attention. They also roll on the floor and tread with back legs becoming very vocal. According to some findings, if you see a cat crying all night, it might mean she is on her heat cycle.

img source

These behavior changes can mislead the owners into thinking their cat has some sort of unusual illness. But this is just part of their normal lives.

Cats can sometimes have vaginal bleeding as well but don’t mislead yourself into thinking it a menstrual cycle like female humans. This could be pregnancy of miscarriage of a little kitten. It’s a clear sign, she needs medical attention.
An equally surprising fact is, you can prevent your kitty from experiencing frustrating heat cycle by getting her spayed. All it requires is a surgical process which not only eliminates her discomfort rather save her from enduring the hormonally influenced behaviors of estrus.
Hope this read saved your day and revealed a lot new stuff to you.