Arterial Blood Gases. Test Overview. An arterial blood gas (ABG) test measures the acidity (pH) and the levels of oxygen and carbon dioxide in the blood from an artery. This test is used to check how well your lungs are able to move oxygen into the blood and remove carbon dioxide from the blood.
How Often the Test Is Done During Your Pregnancy. Your doctor may use the Doppler often to listen to your baby's heartbeat during routine checkups, starting at about 8 to 10 weeks. Handheld Dopplers will not work quite this early.
Your doctor will ask about your medical history and your family history of heart disease. Your doctor will also perform a physical exam that includes listening to your heart with a stethoscope. Mitral valve regurgitation usually produces a heart murmur, the sound of blood leaking backward through the mitral valve.