gerbil birth

Question
Hi how can you tell when a gerbil is going to give birth? Do they squeek alot? im a new gerbil owner i'v never had them befor i have two i think one is a boy and the other is a girl the girl is squeeking alot and she has a relly big tummy im not to shure if it is a girl but i think she's pregnet.Also is there any way i can find out if there is a boy and/or girl? thanks for your time and information have a great day.  

Answer
the best thing to do is to go to this website to sex the gerbils. it's easier to see a picture than for someone to tell you. http://www.geocities.com/celticcliquegerbils/SexingGerbils.html

also,if you look at your gerbil from above and it's stomach is very round and oval shaped than more than likely she is pregnant. the female will start making a nest in a specific area of the habitat as well.