Puffer Pregnancy?

I have a male and two female Dwarf puffers in a 10 gal. I have noticed that one of the females has a distended lower abdomen. At first I thought it was that she had just eaten a lot, but that isn't the case. I was wondering if anyone knows about dwarf puffer pregnancies and if she actually might have eggs? I have read that it is rare and difficult for puffers to breed in captivity. I have been trying to try to get a picture of her and she keeps darting away from me, if I can get one I will post it asap. I know a pic would help determine if she really is.
Thanks for all the help!

I'll take a look and see. Thanks for the link.
I woke up this morning to find my female puffer slim again and not full and round on her lower abdomen like she was last night. I wonder if she really did lay her eggs while I was sleeping. I am worried that I will never find the eggs or they have already been sucked up by the filter! I would love to have DP babies.