is my guinea pregnant?

Question
both piggies i received are female I believe she was pregnant when we got her from the pet shop
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should I seperate them - will one kill the other or the babies like hamsters sometimes do
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Hi, I got 2 guineas for Christmas and I'm sure they are both female, the lady in the pet shop said they were anyway. One of th guineas is albino, it is about 10 weeks old and I think it might be pregnant. Its eating an awful lot of food, its tummy seems a little round and I noticed today that its nipples were showing near its bum. I'd not noticed them before. Could it be pregnant?
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It is possible that she could be pregnant. Guinea pigs are pregnant on average for about two months. If you touch her stomach and you feel something moving than she is probably pregnant. The only thing you can really do is wait and see. If she is pregnant be sure to give her extra vitamins and nutrients. She will certainly need them. Also have a vet ready in mind in case she gets sick during or after the pregnancy.
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I would personally keep the male and female away permanently unless the male is neutered. They won't fight and kill each other, but the problem will be with her constantly getting pregnant. The chances of the mother and pups dieing increases with each pregnancy.I never recommend breeding guinea pigs unless you buy guinea pigs from reputable breeders and you plan to show them.

Answer
Oh I am sorry about that. You can keep both females together in the cage. The other one might help the pregnant female. Yeah you bought her pregnant and that's always a risk when buying females because something they may not have seperated them in time. Guinea pigs are pregnant for about two months. Here is a link for more info on guinea pig birth and reproduction.
http://www.guinealynx.info/reproduction.html