Second‐trimester amniocentesis vs. chorionic villus sampling for prenatal diagnosis in multiple gestations

Abstract

AbstractObjectiveTo study the impact of invasive procedures for prenatal diagnosis on multiple pregnancies and compare first‐trimester chorionic villus sampling with second‐trimester amniocentesis.DesignRetrospective study of 347 second‐trimester amniocenteses and 69 chorionic villus sampling procedures.ResultsMiscarriage occurred in 4.18% of women after amniocentesis and 4.54% of women after chorionic villus sampling. In the amniocentesis group the risk of miscarriage was higher in the cases with transplacental entry (4.54%) than in those with transamniotic entry (2.08%). The rates of preterm delivery ≤ 32 weeks and preterm delivery ≤ 35 weeks in the amniocentesis group were 11.8% and 32.4% and in the chorionic villus sampling group 16.66% and 23.8%, respectively. Total fetal loss rate was similar in the amniocentesis group (8.8%) and the chorionic villus sampling group (10.22%). In the 21 cases where selective feticide was carried out the total fetal loss rate was lower in the chorionic villus sampling group (8.3%) than in the amniocentesis group (11.1%), although the difference did not reach statistical significance.ConclusionChorionic villus sampling appears to be a safe alternative to amniocentesis and should be considered as the method of choice particularly when there is a high risk of an affected fetus necessitating selective feticide. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology