Why can't get guinea pig pregnant?

Guinea Pig give birth to many baby Guinea pigs at one pregnancy.In average,they give birth to 4 Guinea Piglets.So,it will be difficult to care so much babies.And these babies may mate each other and again give birth to so many piglets.But its your option to choose!

Also,most of the female Guinea Pigs die when they are pregnant and the pregnancy stage is critical in female Guinea pigs.