Breeding (And Why You Shouldn't Do It!)
Ah, the romance of nature. But did you know that female guinea pigs can be sexually mature as early as 4 weeks of age?! Yes, that's true. And once one pregnancy is over, which they only last around 59- 73 days, and the litters are 1-4, they can get pregnant again quickly!
So, its very important to sex your guinea pigs (Determining the gender). If you get the guinea pigs from a rescue center, they may already know the genders. Do NOT house opposite genders unless you want unexpected pregnancy's.
Not only is it stressful for the mother, it can be stressful on you too! The momma will have alot of trouble birthing them, even so after 8 months of age and no previous pregnancies!
Short story, if you don't want to put your guinea pigs through pain, keep sows (females) and boars (males) from each other at all times. As any other rodent, they have back to back pregnancies.
If you find out one of your sows are pregnant, the first step is to remove the boars from the cage. Next would be to go to a vet and ask for help determining the pregnancy and asking for help.
Now, if you are stubborn and still want to keep sows and boars together, you might think "what about neutering them?!"
How about, no! Neutering carries MANY health risk and even death in some cases. It would be much easier to keep the two gender separated, unless you know for a fact you want to breed, and you know what you're doing.
Breeding usually ends with death for the sow and the pups. Which is why almost everywhere people will tell you, DO NOT BREED! The pups are born with all their fur, pretty large, and ready to move. This puts alot of pressure on the sow throughout pregnancy and the sow's weight can even double, which will lead to more health risks.
In short, please do not breed. If you really want to breed, read up on it on multiple books you can get, or even sit down with your vet and discuss breeding.