Do cats have periods?

An intact cat that is still on its fertile years will regularly go into its heat cycle. Cats are polyestrus animals thus cat parents would regularly see the pet manifesting signs of being in heat. To attract a potential mate, a cat would call and emit a distinct scent. Cats are noted for their aloof personality but an owner of a cat in heat would be surprised at the pet’s affectionate behavior. However, there is one common sign of being in heat that cats do not show. Humans, dogs and other animals have periods. Period or menstruation in humans and in other mammals which is characterized by vaginal bleeding does not occur in cats. Cats have heat cycles but these animals do not have periods.

Period or menstruation typically occurs in all mammals with placenta. Placental mammals nourish the unborn young through an embryonic organ called placenta. A placenta is attached to the uterus of the mother and delivers oxygen and nutrients to the unborn young. Mammals have the same reproductive system. Mammals have ovaries that release estrogen and progesterone sex hormones. The ovaries also periodically release eggs that will be fertilized by the sperm. Every menstrual cycle or every period as what it is commonly called, the uterus will prepare for the possible fertilization of an egg. To create an optimal environment for the fetus, the uterus will be lined with blood vessel-rich glandular tissues. This preparation of the uterus will need to be cleaned out if an egg was not fertilized. A spring cleaning is necessary to prepare the uterus for the next cycle. The unfertilized egg as well as the endometrium has to be shed and this will come out as menstruation or vaginal bleeding. Menstrual flow will include blood and cervical mucus, the thickened endometrial tissues as well as other vaginal secretions.

Cats are placental mammals too but these animals do not have periods. Vaginal bleeding is not one of the signs that a cat is in heat. This is due to the fact that cat are induced ovulators. Cats’ ovaries will only release ripened eggs when mated. When mating, tom cats would bite the scruff of the queen’s neck. This act is said to trigger ovulation. Cat penis has backward facing keratinous barbs. When the penis is withdrawn after copulation, the barbs would rake against the vaginal walls. This is what causes the female cat to let out a blood curling scream. The pain caused by the backward facing spines would also trigger ovulation. After being mated, the cat would release ripened eggs in 24 to 48 hours.

Cats go into heat regularly. These animals will emit distinct scents that will attract tom cats within smelling distance. Female cats in heat will excessively vocalize. Cats though would not have vaginal bleeding…cats do not have periods because these animals belong to the species that reabsorb the endometrial lining if conception does not occur. Because the womb of cats is quite small, it is expected that the endometrium lining as well as the glandular tissues would be as well small and therefore can be easily absorbed. Cats are polyestrous and it is highly possible for a cat to go into heat every three weeks. Although the blood that will be shed during a period is minimal, imagine how much blood a cat will lose because of the frequency of its heat cycle. Cats have a very efficient reproductive system. As cats are induced ovulators, the body would not need to prepare the uterus if mating did not occur. Moreover, the absorbed endometrium and the blood that was not shed will be very important in the maintenance of the cat’s optimum health.