How to tell when a female mouse is pregnant

I ended up with a temporary pet mouse 2 weeks ago and I thought at that time that it was pregnant. In those 2 weeks, I have no noticed her getting any bigger, so I was just wondering what to look for, cause if she I am going to keep her until she gives birth.

She looks somewhat big in her abdomen area and there are very pronounced nipples.

I could post a pic later on if that would help...

they look like they swallowed a golf ball when they get close to giving birth....thats the best way to put it..

She came out of the feeder bin, which has males and females mixed. Pretty safe to say she is expecting then?

maybe or maybe not....

here is a pretty good site on care and breeding mice...

http://www.horns.freeserve.co.uk/mousenew.htm


it has some helpful info....read it over....it explains stuff better than i can.