Generally, if you are going to breed your guinea pigs, you need to do it by the six-month mark for safety. However, accidents happen, like pet stores incorrectly sexing a male and placing him in the female cage. These lead to pregnancy in older guinea pigs.
If you discover your guinea pig is pregnant and older than six months, you should seek veterinary advice for the best possible outcome.
How Guinea Pig Pregnancies Work
Guinea pigs give birth to anywhere between 2 and 7 pups on average, though they can have more. Female guinea pigs have two uterine horns, each with a number of possible implantation points. Pregnancies last between 59 and 72 days, and guinea pig pups are born fully formed.
Why Having Older Pregnant Guinea Pigs is a Risk
The issue with pregnancy in older guinea pigs is the pelvic bones. In older guinea pigs, these bones fuse. That means when it’s time to give birth, they do not spread the same way that a younger guinea pig’s would. This can lead to complications during the birth process and the death of the mom along with pups.
This complication is more of a problem if the litter in question is the guinea pig’s first. If the piggle had a litter when she was younger, there’s less risk involved since her pelvis already widened. However, it’s not a surefire thing, and best not to risk it.
How to Help Your Guinea Pig
If you suspect you have an older pregnant guinea pig, you can make changes to help her at home, though you’re encouraged to get in with a vet too. These changes reduce the stress on your guinea pig, which in turn can help her through the experience safely. After all, stress and pregnancy do not mix.
If your guinea pig shares a cage, it’s best to move her companions to another cage. If possible, put the new cage next to the old one so the guinea pigs can still interact. Having her own space and not feeling any competition allows her to rest when she needs it.
Additionally, you should up the available food and vegetables for any pregnant guinea pig. Growing little piggles takes a lot out of the mother, and she needs the calories. Adding in a mix of safe vegetables also means she has the right nutrients.
You should also stop picking up any guinea pig that you think is pregnant, apart from the absolute necessities like cage cleaning. Her organs are getting smushed as the pups grow as well as the general awkwardness of her shape. Let her keep her feet under her where possible.
Pregnant guinea pigs also need places to hide. If you’re using something with a small doorway as a hideout, you need to figure out how to replace that as her sides grow. In a pinch, draping an old towel over one end of the cage will work.
It’s important to note that all these steps only mitigate some of the risks involved with pregnancy in guinea pigs, especially older ones. You need to decide with your vet if you want to try a c-section or other intervention or trust your piggle.