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 determine your baby's gestational age and the position of the placenta. You'll lie on your back on an exam table and lift your shirt to expose your abdomen. 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 The tissue sample from the placenta will be withdrawn into a syringe, and the needle will be removed.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. You might feel cramping while the tissue sample is removed.
If your health care provider isn't able to remove an adequate amount of tissue on the first try, the procedure might need to be repeated.
After the procedure
After the tissue sample is removed, your health care provider will monitor your baby's heart rate. You might experience a small amount of vaginal bleeding immediately after the procedure. Your health care provider might schedule an ultrasound a couple of days after chorionic villus sampling to check on your baby.
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 or a couple of weeks, depending on the complexity of the lab analysis.
Contact your health care provider if you have:
Oct. 17, 2015
- Fluid leaking from your vagina
- Heavy bleeding
- A fever
- Uterine contractions
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