What you can expect

Chorionic villus sampling is usually done in an outpatient facility or the health care provider's office.

During the procedure

First, your health care provider will use ultrasound to verify your baby's gestational age and the position of the placenta. You'll lie on your back on an exam table with your abdomen exposed. Your health care provider will apply a special gel to your abdomen, and then use a small device known as an ultrasound transducer to show your baby's position on a monitor.

Next, your health care provider will use the ultrasound image as a guide and take the tissue sample from the placenta while you lie still. This can be done through your cervix (transcervical) or your abdominal wall (transabdominal).

• Transabdominal chorionic villus sampling. After cleansing your abdomen with an antiseptic, your health care provider will insert a long, thin needle through your abdominal wall and into your uterus. You might notice a stinging sensation when the needle enters your skin, and you might feel cramping when the needle enters your uterus. The tissue sample from the placenta will be withdrawn into a syringe, and the needle will be removed.
• Transcervical chorionic villus sampling. After cleansing your vagina and cervix with an antiseptic, your health care provider will open your vagina with a speculum and insert a thin, hollow tube through your cervix. When the catheter reaches the placenta, gentle suction will be used to remove a small tissue sample.

After the procedure

You might experience a small amount of vaginal bleeding immediately after the procedure.

You can resume your normal activity level after the procedure. However, you might consider avoiding strenuous exercise and sexual activity for a day.

Meanwhile, the tissue sample will be analyzed in a lab. Results might take a few days to a week or so, depending on the complexity of the lab analysis.

Contact your health care provider if you have:

• Fluid leaking from your vagina
• Heavy bleeding
• A fever
• Uterine contractions