https://www.purina.com/articles/cat/health/when-do-cats-go-into-heat

And certain breeds—like Siamese—may go into heat as early as 4 months, while ... A cat can go back into heat one week to one month after delivering kittens.

https://www.thesprucepets.com/signs-that-your-cat-is-in-heat-3385392

May 14, 2019 ... Female cats who have not been spayed will go into heat. Learn how to identify this normal cycle and whether or not you need to do something about it. ... This first heat cycle is called puberty and a cat can get pregnant during any of its heat cycles, including the first one. ... Get Your Free Kitten Care Guide!

http://www.animalplanet.com/pets/at-what-age-do-cats-go-into-heat/

Cats go into heat at different ages. ... at-what-age-do-cats-go-into-heat0 ... Your sweet, leggy kitten could be in hormonal turmoil well before she hits the 6-month  ...

http://fixnation.org/2014/02/5-signs-your-cat-is-in-heat/

A cat comes into heat when she sexually matures, meaning that she is fertile ... but may experience their first heat as young as 4 months old, with 6 months ... with the heaviest “kitten season” running from March through September. ... Escape attempts – Indoor cats will do their best to escape outside to seek a male partner.

https://vcahospitals.com/know-your-pet/estrus-cycles-in-cats

Cats have their first estrous (reproductive) cycle when they reach puberty. ... How often does a female cat come into heat? ... How long does estrus last? ... for letting a cat have an estrous cycle or have a litter of kittens before being spayed.

https://www.youtube.com/watch?v=L8EO7Yo600I

Dec 18, 2008 ... Kittens will generally go into heat around six, eight or 12 months of age, ... Get a cat spayed before the first heat cycle to prevent mammary ...

https://cattime.com/cat-facts/25353-cat-in-heat-signs-symptoms-what-to-do-if-your-cat-is-in-heat

Female cats who aren't spayed will go into heat from the time they are six to ten ... cat is ready for mating, it is not advised to breed a kitten during her first heat.

https://pethelpful.com/cats/My-Cat-Is-In-Heat-kitten

Mar 15, 2019 ... However, they do not go into heat themselves. ... There are a number of clear signs that your cat or kitten is in heat: .... Pheromone products: First introduced in the United States in 2001, pheromone-based products have been ...

https://pets.thenest.com/old-kitten-goes-heat-7846.html

Female kittens often enter into their first heat cycle or "estrus" at around 5 to 6 ... Not only does spaying prevent your kitten from going into heat, it prevents ...

https://www.petmd.com/cat/care/evr_ct_cat-facts-how-long-are-cats-in-heat

When Do Cats Go Into Heat? ... My Cat's Pregnant, What Do I Do? ... The amount of time it takes a cat to deliver her kittens will vary depending on the size and ...