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Home > Guinea Pigs > At What Age Do Guinea Pigs Reach Sexual Maturity?

At What Age Do Guinea Pigs Reach Sexual Maturity?

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Dr. Maxbetter Vizelberg

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Guinea pigs make excellent pets, especially for first-time pet owners, like children. These cute little animals have few health problems, are low-maintenance, and are great for kids as the guinea pig isn’t as delicate as some other small pets. If you have multiple guinea pigs in your home—and these guinea pigs are of different sexes—you need to be careful about how you’re housing them, though.

The guinea pig, like other smaller rodents, matures quite quickly. That means if you have males and females housed together, they could end up breeding sooner than you think. In fact, guinea pigs typically reach sexual maturity around 3–4 months, so it’s best to house males and females separately from the get-go.

Curious about guinea pigs and when they’re able to breed? Then, keep reading to find out everything you need to know.


The Estrus Cycle in Guinea Pigs

Though guinea pigs usually reach sexual maturity around the 3–4 month mark, some may mature faster and reach maturity around the 2–3 month mark. But what happens after they reach maturity? For females, the estrus cycle begins.

The estrus cycle is simply the cycle between ovulation (the reproductive cycle). For guinea pigs, once a female reaches sexual maturity, she will go into heat every 13–21 days. The female is then fertile for 6–11 hours, during which time she can be mated (this period typically occurs at night). Male guinea pigs have no cycle; instead, the males of the species will mate with any female in heat it comes across at any time.

guinea pig pregnant
Image By: minka2507, Pixabay

Pregnancy in Guinea Pigs

So, how long does pregnancy in guinea pigs last? The gestation period of the guinea pig can last anywhere from 59 to 72 days. And guinea pigs will give birth to litters that vary in size from a single pup to eight pups (the norm is more like two to four, though). Plus, female guinea pigs can have litter up to five times a year!

However, one thing to know about female guinea pigs, particularly if you’re purposely trying to breed one, is that it’s best if she gives birth to a litter before she reaches 8 months. After that, if the female has not given birth, the bones of the pelvis become more tightly fused together, making the birthing process more difficult.

Another important thing to know is that giving birth can also result in something known as pregnancy toxemia. Pregnancy toxemia is a life-threatening metabolic disorder that leaves the mother guinea pig with high blood pressure and low blood calcium. This can lead to loss of appetite, twitching of muscles, coma, and death. So, if you have a pregnant guinea pig on your hands, be sure to give it lots of water and greens that are high in calcium throughout the pregnancy.

black cream guinea pig
Image By: Petra, Pixabay

Can I Get My Guinea Pig Spayed to Avoid Pregnancy?

You can get your guinea pigs spayed or neutered to prevent unwanted pregnancy, but you should know that it may not be the ideal solution. Because guinea pigs are so small, the risks of castration are typically higher than those of a cat or dog (especially since they tend not to do well under anesthesia). The associated costs can also be higher than a spay or neuter for a larger animal.

If you do want to get your guinea pig spayed rather than housing sexes separately, it’s recommended that the males be neutered. Neutering a male is an easier and shorter procedure than spaying a female. Separate housing is your best and safest means for avoiding unwanted pregnancies.

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Guinea pigs reach sexual maturity very early, typically around 3–4 months. That’s why it’s essential to house males and females separately early on; this way, you can avoid unwanted pregnancy. Because females go into heat roughly every 13–12 days, it can be quite easy for them to become pregnant if living with males. And females can have litters up to 5 times a year (which equals lots of baby guinea pigs for you to handle)!

While you can have your guinea pigs spayed or neutered, it comes with a lot of health risks—more than with cats or dogs. The best and safest way to avoid unwanted pregnancy in your guinea pigs is simply through separate housing.

Featured Image Credit: Charleen Magne, Shutterstock

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