women s health issues
Medical Care During Pregnancy
Ultrasonography
Most doctors believe that Ultrasonography , the safest imaging procedure, should be done at least once during a pregnancy to make sure the fetus is normally formed and to verify the expected date of delivery. It is usually done between 16 and 20 weeks of pregnancy. For the procedure, a device that produces sound waves (transducer) is placed on the woman’s abdomen. The sound waves are processed to form an image that is displayed on a monitor. Sometimes, particularly during early pregnancy, the doctor uses an ultrasound device that can be inserted in the vagina. Ultrasonography produces high-quality images, including live-action images that show the fetus in motion. These images provide the doctor with useful information and can reassure a pregnant woman. Ultrasonography can also be used to do the following: Show the fetus’s beating heart and thus confirm that the fetus is alive, as early as 5 weeks of pregnancy Identify the sex of the fetus, as early as 14 weeks of pregnancy See whether a woman is carrying more than one fetus Identify abnormalities, such as a mislocated placenta ( Placenta Previa ), too much fluid in the sac that contains the fetus ( Date the pregnancy and thus help determine whether the pregnancy is progressing normally Identify birth defects (sometimes) Check for evidence of Down Syndrome (Trisomy 21) (and some other disorders) by measuring the fluid-filled space near the back of the fetus’s neck (called nuchal translucency) Guide the placement of instruments during certain procedures, such as prenatal diagnostic testing Toward the end of pregnancy, ultrasonography may be used to identify premature rupture of the fluid-filled membranes containing the fetus. Ultrasonography can provide information that helps doctors decide whether cesarean delivery is needed. 