Comprehensive analysis of early pregnancy loss based on cytogenetic findings from a tertiary referral center

Abstract

Background Pregnancy loss is one of the most common complications during pregnancy. Clinical consultation and comprehensive understanding of the etiology are critical for reducing anxiety, distress, and depression. This study aimed to perform a comprehensive analysis for products of conception (POC) in miscarriage based on genetic etiology and clinical information. Methods Retrospective observation was performed on cytogenetic findings of 1252 POC form spontaneous pregnancy loss over an 11-year period. The frequencies and profiles of chromosomal abnormalities were discussed according to the classification of women with different maternal age, previous miscarriage history, normal live birth history, and different mode of conception. Results A total of 667 (53.2%) chromosomal abnormalities were observed, including 597 (47.7%) cases of numerical abnormalities, 33 (2.6%) cases of unbalanced structural abnormalities, 32 (2.6%) cases of mosaicism, and 5 (0.4%) cases of balanced rearrangement. In group of women above 40 years of age, the detection rates of chromosomal abnormalities and viable autosomal trisomy were significantly higher than those in groups of ≤ 29, 30 ~ 34, 35 ~ 39 years of age (p < 0.05). The detection rate of abnormal karyotype in women with normal live birth history was 61.1%, significantly higher than 52.5% in women without normal live birth history (p < 0.05). There was no significant difference among women without, with 1–2, and ≥ 3 previous miscarriages in the rate of abnormal karyotype (p > 0.05), and viable autosomal trisomy was less common in women with ≥ 3 previous miscarriages. The frequency of chromosomal abnormalities was 49.0% and 41.0% in women with assisted conception and natural conception (p > 0.05), respectively, and monosomy X was more frequently detected in women with natural conception. Conclusion The frequencies and profiles of chromosomal abnormalities in early miscarriages are strongly associated with clinical information including the maternal age, previous miscarriage, live birth history, and mode of conception. Even in women with a first miscarriage, or with a history of normal live births, chromosomal analysis of POC should be recommended for etiological assessment.