Chorionic Villus Sampling Indications for CVS are essentially the same as those for amniocentesis, except for analyses that require amniotic fluid rather than amniotic fluid cells. Chorionic villus sampling is generally performed at Placental villi may be obtained through transcervical, transabdominal, and transvaginal access to the placenta. Later in pregnancy, when a fetal malformation or IUGR is There have been three major collaborative studies comparing CVS and amniocentesis. A European study reported an excess loss rate in the CVS group that was different both clinically and statistically from the results of the other two large Prenatal cytogenetic diagnosis is occasionally complicated by the finding of more than one distinct cell line obtained from a single chorionic villus sample. When this occurs, it may be the result of fetal karyotypic mosaicism, confined placental mosaicism, or pseudomosaicism.
Fetal mosaicism represents two distinct cytogenetic cell lines in the fetus.
Confined placental mosaicism is defined as two cell lines that occur only in the placenta and not in the fetus. Pseudomosaicism represents two or more cell lines that have arisen in cell culture but are not representative of the Poor pregnancy outcome and perinatal loss have been reported in association with confined placental mosaicism. The utility and method of antepartum There have been reports of an association between CVS and limb reduction and oromandibular defects. Cavernous hemangiomas have also been reported. The risk for these anomalies is unclear.