[Pregnancy outcome after early amniocentesis]

The indications, karyotype, and outcome of 1812 pregnancies following midtrimester amniocentesis (eACZ/as) performed from 1977 to 1989 are presented, especially regarding the risk of pathologic karyotypes and spontaneous abortion. There were 37 pathologic karyotypes (trisomy 21 in 24 pregnancies). The spontaneous abortion rate following amniocentesis was 2.8% although it was almost halved after direct ultrasound guidance had been introduced (1.87% versus 3.66%). In gravidas with previous spontaneous abortion, the preterm delivery rate and spontaneous abortion rates following rACZ were significantly increased. There is a progressive increase of the spontaneous abortion rate after eACZ with the number of previous spontaneous abortions; 5.83% when there was only 1 previous spontaneous abortion, 7.83% when there were 2, and 8.75% when there were 3 or more spontaneous abortions. Previous spontaneous abortions do not increase the risk of chromosomal aberration. In women aged 37 years or more the risk of trisomy 21 is 0.69%, aged 38 years 1.55% and over 39 years 0.44%. The risk is rapidly increasing after 40 years of age (2.25%). The proportion of pathologic karyotypes in these age groups was significantly higher in comparison to younger women. The age limit of 37-38 years as the indication of a possible appearance of mid-trimester ACZ is discussed.