Oh Rats! Is it dead?

Strange question, I know, but I'm really afraid to check so I'm not going to.
A few years ago my nephew, Steven, gave me his pet rat, Spike. I enjoyed having Spike as my classroom pet at school for two years until one day he started convulsing and then seemed to slip into a coma. I didn't know what was wrong with him so I gave him extra food and water and left for the evening. When I arrived the next morning Spike was stiff as a board. It took me all day to get the nerve up to dispose of him and even then I almost lost it. I felt so terrible but all the research I did pointed Spike's death to old age. After he died I decided to purchase another rat. The kids at school loved having a class pet and Michael really enjoyed him when he came home for Christmas and summer vacations.
So we went to the pet store and picked out two little girl rats. We named them Nutmeg, she's brown, and Maggie. They were also great to have in the classroom. But I got tired of retrieving pencils and other objects from their cage as some kids just couldn't resist the temptation to stick stuff in there so I brought them home for the summer and never took them back this year.
As you all probably know by now, I'm pregnant...due in March and I'm not terrible excited to have a couple of rats in my home anymore. They are fun to watch but I don't like playing with them or letting them wander around much/at all. I've actually been meaning to call the pet store to see if they'd take them back but I have yet to make the call. So tonight I went over to their cage to feed them, something I frequently forget to do, and only Meg came running for her dinner. This is very atypical as Maggie is always first in line and often fights Meg for her portion as well. So I'm wondering what's up with Maggie? She didn't even poke her head out of their little purple igloo. So I got down on my hands and knees and peaked as best I could into their igloo and all I could see was Maggie's tail and it was totally still. I tried calling to her but to no avail. She didn't move at all. Now I'm freaked out that she is dead...probably starved to death by me, the worst pet owner of the world. I'm trying to console myself because I know most pet rats don't last too long anyway but I'm kinda worried that she's a goner. I called Derek who is at work and he said not to worry and that he'd take care of it for me when he gets home in the morning. Good thing too because I'm not going near it and I swear if that rat is running around in the morning I'm going to fly through the roof...I'm sure she's dead.
One other option could be that she is currled up in that purple plastic igloo giving birth to baby rats. I did mention that we picked out two girl rats when we purchased them but one day they were "fighting" or trying to "play leapfrog" as Michael interpreted the situation and we've been puzzled by this odd behavior ever since. Now I know what you must be thinking, I'm a biology teacher shouldn't I know how to tell if an animal is a boy or a girl, yes I ought to and I inspected them both quite a bit and didn't find signs to contrary but their behavior at times makes me wonder if one of them suffers from undescended testicles or something. Well this is turning into quite the strange blog so I think I'll stop right about here, but I'm just trying to give myself some hope that Maggie is not really dead. I'm afraid in reality she has passed on to rat heaven. Poor girl.
Thank goodness for husbands at these difficult times. I'm so glad Derek is so willing to dispose of our little friend for me, not to mention how sweet it is that he wants me to stay far away from the cage and the dead rat...in my condition of course! It's too bad they are too big to flush down the toilet, especially since our garbage doesn't get picked up until Wed. morning. I guess he'll have to transport her to a dumpster somewhere...yuck! Okay, gross that's all.