how do i know if my hamster is pregnant

Question
hi i placed my male hamster with my female hamster the female ent in a freezing position and the male mounted her then he stoped. i'm guessing this is mating. they did the same thing 16 days ago when i thought my female was pregnant. she came out of his cage as a very big hamster. is she pregnant? can you tell me about the hamsters behavior from day 1-16 please. my hamsters are Syrians. her lower body is much bigger than her lower body.she has a kinda growing abdomen. please get back to me as soon as possible.

Answer
Hi Lesley,

    It is possible that your hamster is pregnant. Two best ways to tell if your hamster is pregnant: First check to see if she comes back into heat (check her on the 3rd and 4th day after she has been with the male). Females come into heat every 3-4 days. You can do this by firmly stroking down her back (from head to tail). If she freezes then she is not pregnant. The other way is the female will poof out around her middle area (become really fat) on or around the 10th day after mating. She will also start hoarding food more than usual and build a big nest.
    If you feel your hamster is pregnant, start feeding her high protein foods like hard boiled egg and diced carrots (4-5 pieces of each, every evening when she is up). Also 3 days before she is due, clean the cage and put in extra bedding and remove the wheel. Remember not to touch the nest or the babies until the babies are 2 weeks old. This is when it is safe to handle the babies for a short period of time and the cage can also be cleaned at this time.
    At 3 weeks of age, the babies will need to be separated from Mother and each other (boys in one cage, girls in another). At this time you can stop feeding the mother the hard boiled egg.
    At 5-6 weeks, the babies will be ready to go to their new homes.
    If you have anymore questions, please write again.

Thank you for writing!