Actually there are a mulititude of complications that can arise in a pregnant guinea pig and they require a lot of extra care during this time. I have a friend who moderates a Cavy board and she would love to help you, I'm sure. She knows everything about guinea pigs!! I'll email her and ask her to reply here or email you. In the meantime, here are a few links to sites and forums that may help you. And please, if you plan on housing your males and females together, please have the males neutered or better yet, keep them in separate cages! Keep us updated!!

http://guinealynx.info/breeding.html
http://www.cavycompendium.com/forums...?s=&forumid=95