Prenatal Diagnosis

Prenatal Diagnosis

Prenatal diagnosis means diagnosis before birth. It is a way for your doctor to see if your developing baby has a problem. The two main methods are amniocentesis and chorionic villus sampling (CVS). These tests help find genetic disorders before birth.

Amniocentesis :

In this procedure, a sample of amniotic fluid (fluid around the baby) is removed from your uterus. A doctor inserts a long, thin needle through your abdomen into your uterus. He or she withdraws a small amount of fluid. The fluid is sent to a laboratory for evaluation. In the lab, the fluid can be tested for:

genetic abnormalities

infection

signs of lung development.

Your body will make more fluid to replace the fluid that is taken out. The baby will not be hurt during the procedure. Some women feel mild cramping during or after the procedure. Your doctor may tell you to rest on the day of the test. Usually you can resume normal activity the next day.

Chorionic Villus Sampling (CVS):

CVS removes a small sample of placenta tissue from the uterus. The sample is then sent to the lab for testing. The sample can be taken 2 ways:

A catheter (thin tube) through the vagina. The catheter is inserted into the vagina. It is passed through the cervix and into the uterus. The doctor uses images from an ultrasound to guide the catheter to the best spot for sampling.

A needle through the abdomen. The sample can also be obtained by inserting a needle into the abdomen. The needle then withdraws placenta tissue. Again, ultrasound is used to guide the needle.

Local anesthesia is used for this test to reduce pain and discomfort. Most women feel fine after the test. Some may have mild bleeding (spotting) afterward.