pregnant women has definitely improved sense of smell... (fact: so you won't be able to ingest unhealthy food for your baby). and maybe it's because of the prenatal vitamins you take. Esp iron supplements, it really does changes the smell and darkens the color of your poop. Plus the fact that pregnant women's internal organs are always adjusting fo the growing womb. So you might expect more gassy stomach too.
The sense of smell is definitely heightened during pregnancy. Heh.