Chromosomal aberrations--the cause of spontaneous abortions

The genetic factor remains the most frequent cause of spontaneous abortions. Examination of the fetal tissue from spontaneous miscarriages shows that 75% of them were caused by abnormal karyotype. Other reasons, albeit rare, included submicroscopic genomic rearrangements, monogenic diseases, and polygenic inheritance disorders of the embryo.

Objective: The aim of the study was to analyze the incidence of chromosomal aberrations in material from the miscarriage.

Methods: The study included 47 samples of miscarriage material from 47 women. Fluorescent hybridization in-situ (FISH) was used for genetic examination.

Results: Chromosomal abnormalities were diagnosed in 72% of the samples, with trisomy 21 (25.5%), trisomy 16 (17%), and trisomy 18 (12.8%) as the most common. An abnormal number of copies of chromosome 18, 21, 22, indicating the coexistence of trisomy 18, 21, 22, was detected in 1 patient. It was another miscarriage in case of 14 subjects (29.8%).

Conclusions: Chromosomal aberrations were diagnosed in the majority of fetal tissue samples from spontaneous miscarriages. More than one chromosomal aberration in a single embryo is an extremely rare occurrence. Miscarriage due to chromosomal aberrations occurred in the vast majority of women > 35 years of age.