chorion villus biopsy in the second ( and third ) trimester is indicated in pregnancies in which oligohydramnios , growth retardation or foetal malformations have been demonstrated by ultrasonic scanning , in cases where referral for antenatal diagnosis is very late and when chromosome investigation after amniocentesis proves unsuccessful and repeated amniocentesis would result in an unacceptably late result .
C0032981
third
C0032961
pregnancies