Some pregnant women complain that talking on the phone leaves them winded and searching for breath, which means climbing a flight of stairs can be a tough task. Mamas-to-be who find exercise beyond their ability may want to speak to their obstetricians about their hearts. It is quite common for pregnant women to develop a heart murmur at some point — usually between weeks 15 and 25 — though they often go undetected. The murmurs are due to an increase in the amount of blood flowing through the heart's chambers and are usually non-threatening. In most cases, the murmur disappears after birth. Women who are found to have murmurs may be placed in the care of a cardiologist who will monitor their hearts through electrocardiograms and ultrasounds. Did you experience this?