Comparison of early and mid-trimester amniocentesis in 1459 amniotic fluid cultures

ABSTRACT

Early amniocentesis is a new context in prenatal diagnosis. However, the consequences of this procedure are not known clearly. We compared cytogenetic results of 655 amniotic fluid samples obtained at 12-14 gestational weeks [early amniocentesis, EA] and 804 samples at 15-18 gestational weeks [mid-trimester amniocentesis, MA]. The rate of chromosomal abnormalities for early amniocentesis was 3.2% [21 cases] and for mid-trimester amniocentesis was 5.3% [43 cases] [p=0.047]. True mosaicism was seen in 2 cases MT group [p=1.000]. We did not have maternal cell contamination in either group. The ratio of repeat amniocentesis was 0.6 percent in the EA group compared with 0.2 percent in MA group [p=0.417]. Procedure-related early abortion [within the first 30 days after amniocentesis] was seen in 4 cases of EA [2.2%] and 3 cases of MA [1.5%] [p=0.719]. Hemorrhage occured in the same ratio. Intra-uterine fetal death [IUFD] was seen in 7 cases of MA, but not in any cases of EA [p=0.015]. Our findings showed comparable outcome in two method of amniocentesis, except for lower chromosomal abortion rate and IUFD