Hello, and I hope I can answer your question. Many women feel short of breath during pregnancy, especially when they lie flat due to compression of the blood vessels going to the heart and pressure from the growing uterus. This has nothing to do with having gestational diabetes and is a common condition during pregnancy. It is generally recommended to lie on your side (preferably your left side) when you lie down to minimize the compression. Using pillows to prop your head up higher also may help the problem. I hope this information was helpful, and good luck with the rest of your pregnancy. Best wishes, Dr. Brown