What Is Amniocentesis?
Amniocentesis is the withdrawal of a small amount of amniotic fluid (the water surrounding a developing baby) from the uterus. The procedure is done in a doctor’s office or hospital clinic, usually between the 15th and 18th week of pregnancy. Amniocentesis can sometimes be scheduled as early as about 12 weeks, although the risk may be a little higher. Before the procedure, the doctor performs an ultrasound scan (sonogram) which shows a picture of the uterus, the placenta, the amniotic fluid, and the fetus on a screen. Then the doctor inserts a very thin needle through the woman’s abdominal skin into the uterus. About an ounce or less of amniotic fluid is removed. This fluid contains cells which have been shed from the fetus and which can be tested for certain serious genetic diseases. The fluid also contains various proteins which can be tested to look for other diseases. Some women say amniocentesis doesn’t hurt at all; others say they feel a pressure or cramping. After the sample is
