Chorionic Villus Sampling (CVS)

Chorionic villus sampling (CVS) can cause cramping, leakage of amniotic fluid, and vaginal spotting, which goes away in 1 to 2 days. You may feel some soreness where the needle was put in if you had the belly procedure done.

CVS also increases the chance of:

• Developing a uterine infection.
• Having a miscarriage. The chance of miscarriage is higher for transcervical CVS than for abdominal CVS.¹ Overall, one study showed the risk of miscarriage from CVS is about 1 in 400 when done by a highly trained provider.²
• Having a baby with arm or leg abnormalities though the chance of this happening is very low, especially when the test is done after 10 weeks.

Chorionic villus sampling has a very small chance of causing bleeding that could result in mixing your blood and your baby's. If you have Rh-negative blood, you will be given the Rh immune globulin vaccine (such as RhoGAM) to prevent Rh sensitization which could harm your baby if he or she has Rh-positive blood.

After the procedure

It is normal to have mild cramping, leakage of a small amount amniotic fluid, and vaginal spotting for the first day or two after the procedure. Call your doctor immediately if you have:

• Moderate or severe belly pain or cramping.
• More leakage of amniotic fluid from your vagina.
• More vaginal bleeding than spotting, or bright red bleeding.
• Chills or a fever.
• Dizziness.
• Redness or swelling at the needle site if you had a belly procedure.