Answer: It's quite common for expectant women to be short of breath. Usually it's nothing to be concerned about, but it's best to check with your doctor, since lots of things can cause shortness of breath. As a normal part of pregnancy, your breathing may be affected by the increase in the hormone progesterone, which causes you to breathe in more deeply. This might make you feel as if you're working harder to get air. Breathing may also become more difficult as your enlarging uterus takes up more space, resulting in pressure Maintain good posture when you're sitting or standing (slouching doesn't give your lungs enough room to expand when you breathe). Prop yourself up when sleeping by putting some pillows under the upper body in a semi-sitting position. It reduces the pressure that the uterus places on the lungs. Don't overdo it, whether you're exercising, just walking around, or doing housework. Take your time and respond to your body's cues to slow down or stop altogether. If your shortness of breath has started suddenly, is severe, seems to be worsening, or is associated with pain, coughing, wheezing, or heart palpitations, let your doctor know. These may be signs that something other than pregnancy alone is causing your shortness of breath.