Chromosomal abnormalities of 19,000 couples with recurrent spontaneous abortions: a multicenter study

Abstract

Objective: To investigate the demographic data and karyotypes of 19,000 couples who experienced recurrent spontaneous abortion (RSA).

Design: A cross-sectional study of 19,000 couples.

Setting: Five hospitals.

Patient(s): A total of 19,000 couples experiencing RSA.

Intervention(s): Not applicable.

Main outcome measure(s): Cytogenetic analysis of blood lymphocytes.

Result(s): A total of 844 couples (4.44%) showed chromosomal aberrations in either partner. Females were more likely to have chromosomal aberrations. The mean age of females and males with chromosomal aberrations was younger than that of females and males without chromosomal aberrations. Interestingly, sex and age distribution varied significantly depending on the subtypes of chromosomal aberrations. We detected 324 balanced translocations, including 223 novel ones. They were distributed across all chromosomes; the frequency of balanced translocations decreased according to the numerical order of autosomes (strong negative correlation; r = -0.84). Individuals with balanced translocations were younger than other groups. All 58 inversions, including 25 novel ones, were detected in autosomes; the negative correlation also existed. Thirteen Robertsonian translocations, 5 deletions, and 3 duplications were detected. Six types of Turner variants, triple X mosaicism, and mosaic Down syndrome were detected in females; Klinefelter variants and mosaic XYY syndrome were detected in males. Marker chromosomes at various mosaic levels and 7 different complex chromosomal rearrangements were also observed.

Conclusion(s): Patients who experienced RSA induced by chromosomal aberrations experienced miscarriages at a younger age. Significant correlations existed between the patients' age or sex and the subtypes of chromosomal aberrations. This study detected several chromosomal abnormalities associated with RSA, including various novel aberrations.

Keywords: Recurrent spontaneous abortion; chromosomal abnormalities; numerical aberrations; structural aberrations.