Screens for: Genetic/chromosomal disorders of the baby such as Trisomy 13, Trisomy 18 and Down syndrome.
Who does it: This is typically done by a maternal fetal medicine specialist (MFM) or an OB/GYN.
How it is done: A small needle/catheter is placed either through the abdomen or through the vagina near the uterus to collect a small sample of villi. Ultrasound is used to guide the needle/catheter away from the baby and the placenta.
When is it done: It can be done as early as 8 weeks gestation, though many only offer this between weeks 11-13.
Accuracy: Barring a lab error nearly 100%.
Risk to mom: Small risk of infection from the procedure. Procedure is uncomfortable. You may experience cramping or spotting after the procedure.
Risk to pregnancy/baby: Early CVS, done prior to 11 weeks has a very small percentage of risks of birth defects. Most studies report a less than 1% miscarriage rate from the CVS procedure.
Additional resources:
07/27/07
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