Thank you so much for all the help, its really informative and helps a lot. My guinea pig who I think might be pregnant is going to be 3 months old on July 25th and no she has never given birth before. I got her when she was about 5 weeks old and I think that she may have become pregnant before the age of 5 weeks, seeing as I don't have any male guinea pigs. Is this possible, to become pregnant at such a young age? At times, she looks pregnant and then she doesn't. I don't know whether she has just had a weight gain, or not. But her belly feels like it's going to burst when I touch it. I don't feel any bumps that might be babies though. Thank you so much for all of your help mommacavy!!