A Clinical Review of Midtrimester Amniocentesis

Lee, Sang Ho; Park, Young Soon; Chang, Jae Hyuk; Moon, Zong Soo; Seo, Soo Hyung; Park, Yang Suh; Yun, Sook Kyung

Abstract

OBJECTIVE
We performed this study to analyze the indications, distributions of maternal age and cytogenetic results of midtrimester amniocentesis and to determine the complications and risks of it.
METHODS
This study was retrospectively reviewed 674 cases of midtrimester genetic amniocentesis from January 1997 to October 2001 in Kangdong Sacred Hospital, Hallym University. We analyzed the indications, distributions of maternal and gestational age, chromosomal results, and of which accorded to indications of cytogenetic studies.
RESULTS
The indications of amniocentesis were abnormal maternal serum screening (46.2%), advanced maternal age (> OR =35: 44.8%), abnormal ultrasonographic findings (5.9%), familial history of fetal anomaly (2.8%) and previous history of fetal chromosomal abnormalities (0.3%), in order. The overall incidence of chromosomal aberration was 3.6% (24/674), which were composed of 18 cases of numerical aberrations and 6 cases of structural aberrations. In autosomal aberrations, there were 7 cases of Down's syndrome, 6 cases of Edward syndrome, 1 case of Patau syndrome and 3 cases of Mosaicism. In sex chromosomal aberration, there was a case of Turner syndrome. In chromosomal aberrations according to indications, there was 7.5% (3/40) of chromosomal abnormalities in abnormal ultrasonographic findings group, 3.2% (10/311) in abnormal maternal serum screening group and 3.0% (9/302) in advanced maternal age group. There was statistical significance only in abnormal ultrasonographic findings group. There was no significant complication after amniocentesis except 0.3% (2 cases) of fetal loss.
CONCLUSION
Maternal serum screening, advanced maternal age and antenatal ultrasonograms should be important screening methods for amniocentesis which is considered to the most effective diagnostic procedure for prenatal cytogenetic studies. The karyotyping analysis of midtrimester amniocentesis is efficacious method for evaluation of chromosomal aberrations and genetic counselling for parents.