Spontaneous abortion and recurrent miscarriage: A comparison of cytogenetic diagnosis in 250 cases

OBJECTIVE The purpose of this study was to determine the frequency and distribution of cytogenetically abnormal miscarriages in couples with spontaneous abortions (SA) or recurrent miscarriages (RM). METHODS Karyotyping of specimens from 164 abortuses with SA and 86 abortuses with RM was successfully performed according to the standard cytogenetic methods using G-banding technique. RESULTS Among the total 164 cases of SA group, 81 (49.4%) were euploid and the rest (83, 50.6%) showed chromosomal abnormalities. In RM(≥2) and RM(≥3) group, 31 (36.0%)/27 (34.6%) cases were euploid and 55 (64.0%)/51(65.4%) cases were abnormal, respectively. A statistically significant difference was found in the rate of cytogenetic abnormality between SA and RM groups (P<0.05). In all groups, women with advanced maternal age (≥35 years) had a higher rate of chromosome anomalies compared with women younger than age 35 (normal:abnormal = 32.4%:67.6% for ≥35 years and 53.8%:46.2% for <35 years in SA; 19.2%:80.8%/21.7%:78.3% for ≥35 years and 43.3%:56.7%/40.0%:60.0% for <35 years in RM(≥2) and RM(≥3), respectively; P<0.05). In SA group, an increase of normal karyotypes was noted with increased gestational age (<10 week, 38.0%; 10-15 week, 53.5%; 16-20 week, 65.7%). In RM group, most of cases were in <10 week and the frequency of trisomies with chromosomes 1 to 10 were increased compared with that of SA. CONCLUSION There was a statistically significant difference in the frequency and distribution of chromosomal abnormalities between SA and RM groups. Our results will provide useful information for diagnosis and genetic counseling of patients with SA or RM.