I just bought a female Guinea Pig from the pet store. She is very small, she cannot be more than 3 weeks old at the most. My male Guinea pig is over 2 years old and very fat (obese). The moment I introduced the female into the cage, my fat male Guinea pig started to make rumblings (I assumed he was horny), and it looked very obviously like he was trying to have intercourse with her.

Is my female too young to have sex and/or have babies? My Male is roughly about 5 times the size of her. Can they have intercourse despite the size difference? They are current;y separated until I garner the correct information

Thank you.

well guinea pigs can breed in 60days from birth im guessing that the baby female is more than 60 days old so don't put them in the same cage together unless you want a lot of baby guinea pigs

She is far too young to have babies. It is possible, but if she were to get pregnent so young it would Kill her. Don't risk it! pets question and answers,www.5d2d.com

Get you boar neutered, and 6 weeks after the op they can be introduced and should get along great.

Edit to Clarify, since the answer below seems to be confusing my response...

Guinea pigs can breeed from being 3 or 4 weeks old. so she is old enough biologically, However, she is FAR TOO YOUNG (as the other poster said, she is far too young to hae babies safely.)

If the strain they put on her growing body doesnt kill her, it's likely they will as they grow (they can rupture a young guinea pig's uterus).

Owner of two baby boars from a rescue.

REHOME, NEVER BUY!!!
http://www.milhaven-rescue.com/

She is not too young - she is WAY TOO YOUNG to safely have babies!!!!! However. she is not young to get bred, if not today, very soon. Get her out from with the boar AT ONCE!!!!

With sows that are too young, you run the risk of increased delivery problems. Also, with a sow that is too young and they usually wind up stunted as adults because they were investing energy in growing pups instead of growing their own body. Sows should be at least 3 MONTHS old and at least 22 oz (625 g) before breeding and 25 or 26 oz is a lot better (710-740g). Sows should be bred by the time they are 6 months old but 3 WEEKS is way too young!!!

pets question and answers,www.5d2d.com

Before you breeder her, you should ask yourself the 6 questions below and, if you cannot answer yes to all 6 without ANY hesitation, do not even think about putting her in with the boar without having him neutered first.

The 6 questions:
1) Do I have a good reason for wanting to breed? (having pups would be fun and similar reasons are not good reasons)
2) Am I prepared to spend what it takes to buy genetically sound foundation stock? (2 pet store pigs are not sound foundation stock)
3) Am I prepared to put my sows at a 20% risk of dying from pregnancy related issues each time I breed them?
4) Am I prepared to spend what it takes on quality feed and housing, including extra cages for the boar(s) while the sows are pregnant and to separate young boars and sows?
5) Am I prepared to cover the costs of any needed vet care?
6) Am I prepared to find permanent homes for up to 6 pups per litter? (dumping them at a shelter or rescue in not a suitable choice)

Also please remember that the risk in #3 only refers to sows in the optimum breeding group, sows between 3 and 8 months on their first litter or older sows which have already delivered a problem-free litter. Younger sows run an increased risk (30% or so) and sows delivering for the first time at over a year run a 505-80% chance of dying!

EDIT

You sir, are a TROLL! I should have known better than to give you a serious answer but I didn't notice who the poster was until I had already answered your question. You don't have to be a PETA nut to be for animal owners acting responsibility and considering the fate of the animals thay own and any they might cause to be brought into the world. As a breeder of guinea pigs and rabbits for over 40 years I have no sympathy for PETA or for those who condemn the keeping or even eating of animals. I also hope that those of us who are breeders do so with high ethical standards and concern for the animals in our care. In my opinion, to use animals is an acceptable human behavior but to misuse them, as you have repeatedly suggested in your series of posts, is not!

40+ years of responsibly raising and showing guinea pigs

yes to is too young wait until she is 6 months old and put then together and she will have the babies at the right time