Hi fixingit!
I have had three children, and moderate the pregnant/nursing area here.
While I know it is definitely possible to conceive and carry a baby to term at 300+ pounds, it does present some difficulties. One of the biggest things that I can think of off hand, is the fact that the more overweight a person is, the harder and more risky it is for the physician to perform surgery. Basically, it's a lot easier and less risky to perform a c-section on someone of an average weight, or even overweight, than it is on someone who is extremely obese.
If you are not already pregnant, the best thing that you can do for yourself, and for a future baby, is to start working on your health NOW. Even small changes-baby steps-can really make a difference over time. If you are trying to conceive, it is best to start with simple lifestyle changes right now, before pregnancy. Committing to small things-such as eating more fruits and veggies, regular exercise-even if it starts out as only a 10 minute walk each day-can really do wonders for your health.
