Hello, and I hope I can help you today. Feeling short of breath is not unusual while you re pregnant because the hormones of pregnancy actually have a way of telling your brain to breathe faster. This is to ensure that your baby gets enough oxygen, because as your belly gets bigger your lungs are not able to expand as well. So many women feel the sensation of needing to catch their breath all the time when they breathe when they are in the third trimester. In addition, because you would been on bed rest for so long, you probably are not in very good cardiovascular shape. Another possible reason why you could be feeling short of breath is that there is a possibility that you are anemic. Normally, as part of routine prenatal care we check your blood count as well is a test for gestational diabetes somewhere between 24 and 28 weeks. If you ve not yet had this test, it might be a good idea to mention your symptoms to your doctor. Of course, there can be some serious, dangerous things that can cause shortness of breath; like blood clots that spread to your lung, or fluid in the lungs and other pulmonary problems. If you experience any chest pain or severe shortness of breath or start developing a productive cough, you should notify your doctor immediately and possibly go to the hospital for evaluation. I hope that I was able to adequately answer your question today, and that my advice was helpful. Best wishes for the rest of the pregnancy, Dr. Brown