Chromosomal abnormalities of embryos from sporadic and recurrent miscarriages: a tertiary center experience

About 10-15% of all clinical pregnancies end in early spontaneous abortion (SA) and almost half of miscarriages are caused by fetal chromosomal abnormalities. Recurrent pregnancy loss (RPL) is when this situation occurs two or more times before the 20th week of pregnancy. Our study aimed to find the types and frequencies of chromosomal abnormalities in SA and RPL and to perform a comparative analysis.

Cases between 4 and 20 weeks of age were included in the study. The karyotypes of abortions were established using standard cytogenetic analysis, as well as QF-PCR (Quantitative Fluorescence-PCR) method. Comparative cytogenetic analysis was performed between the groups based on miscarriage numbers (SA and RPL) and maternal age (< 35 and ≥ 35).

Maternal age, gestational week, number of miscarriages, and karyotype analysis results were recorded (n = 176). The study included one hundred and six cases with RPL and 70 cases with SA. Abnormal karyotype was detected in 80 cases (45.5%). The most common abnormality was autosomal trisomies (n = 35). There was a significant statistical difference between SA and RPL groups regarding 45, X (monosomy) (p = 0.003). The least chromosomal abnormality type in both groups (SA and RPL) was structural abnormalities (1.4% and 4.7%, respectively). In cases with aneuploidy karyotype, maternal age (≥ 35) was found to be statistically significant (p = 0.003). There was no significant difference between the groups in terms of polyploidy.

Foetal chromosomal karyotypes are still a significant cause of miscarriage. Our findings highlight the diversity of both maternal age and chromosomal abnormalities in spontaneous and recurrent miscarriages. This is also the first study from Türkiye to perform comparative cytogenetic analysis according to these groups.