What is CVS?
Chorionic villus sampling (CVS) is a prenatal test which checks for certain fetal abnormalities such as Down’s syndrome, Tay-Sachs disease, cystic fibrosis and hemophilia., CVS is performed as a biopsy of the chorionic villi found in the mother’s placenta.. These villi make up most of the placenta, yet also contain the same genetic makeup of the baby. Prior to the procedure, an ultrasound is done to assess position of both placenta and baby. If the placenta is accessible a thin flexible tube (catheter) is inserted in the vagina through the cervix and into the placenta for the sampling, otherwise the CVS may be performed from the abdomen, called a transabdominal CVS. The procedure is usually offered between 10 and 12 weeks of pregnancy.
Reasons to consider a CVS:
•Abnormal ultrasound in the first trimester. If you have an ultrasound early in pregnancy, and there is cause for concern, some women prefer to undergo a CVS to rule out or confirm the ultrasound reading.
•History of birth defects or genetic disorders. Women who have a family history, a child, or pregnancy affected by any chromosomal birth defects or genetic disorders are at higher risk. In addition, if mother or partner are known carriers of a genetic disorder.
•Women age 35 or older are considered at higher risk for giving birth to children with chromosomal abnormalities, such as Down’s syndrome.
•Earlier results. Some women prefer CVS over amniocentesis because results are available earlier with regards to decision making.
Risks of CVS
•Cramping may occur during and after the procedure.
•Vaginal bleeding is possible especially with the transcervical CVS
•Miscarriage risk is one in 100. This risk is increased in the transcervical CVS and if the baby is smaller for gestational age.
•Infection may occur from the sampling which is an invasive procedure.
•Rh sensitization. Expectant mothers with Rh negative blood, will be given an Rh immunoglobulin shot following the CVS to prevent an Rh sensitization. On occasion during a CVS, baby’s blood cells may be released into mother’s bloodstream causing antibodies to be produced against the baby.
•Birth defects. Research has shown if the CVS is done too early (i.e. 9th week) it may increase chance of defects in baby’s limbs (fingers or toes).
Similar to amniocentesis this is an invasive test whose primary aim is detection of genetic conditions and chromosomal abnormalities. I would only recommend this test for women who would consider a termination of pregnancy. There are times when one may not know how would respond given the circumstances, and it is important to weigh out the benefits and risks. If you decide to have a CVS consider the following recommendations and natural treatments:
•Rest following the procedure
•Resume activity slowly
Ledum palustre 30C for healing of puncture wounds (3 pellets twice a day for 2 days following procedure).
Arnica montana 30C for trauma and bruising (3 pellets twice a day for 2 days following procedure).