guinea pig babys

Question
my pinky has been pregnant for 76 days and is as flat as a pancake because she
is so fat.
we have been able to here the baby[s] inside her for a week
but they are not coming out.
and one more thing she is nine months old so i'm worried about her safety

Answer
The average gestation period for guinea pigs is from 60 to 70 days, so she isn't too much over the time frame.  If it lasts any longer though, you should definitely take her to the vet.  She is overdue, and you should have her checked out.

Nine months old is not a bad age for her to have a litter.  The pelvic bones fuse together around ten months, so she should be safe.  However, this doesn't mean that there will not be complications, but it also doesn't mean that there will be.  Every litter is different, and it just depends on how it goes, and how big the babies are, and how well the mother guinea pig goes through it.  

She should be about to have her babies any day now, and like I said before, if it lasts any longer, call a veterinarian.  

Good luck!