Recurrent spontaneous abortion related to balanced translocation of chromosomes: two case reports

Abstract

Background Recurrent spontaneous abortion (RSA) is often idiopathic, but structural chromosomal abnormality is an important nosogenesis. Balanced translocations or inversions can lead to unbalanced gametes depending on the specific recombination and segregation patterns during meiosis. An unbalanced karyotype in the conceptus of a couple when one partner has a structural chromosomal abnormality may result in failure to implant, miscarriage, or ongoing pregnancy of a fetus with an unbalanced karyotype. Case presentation We report two rare Han cases of RSA associated with balanced translocation of chromosomes. In case 1, a women who had had four spontaneous abortions, the karyotype was 46, XX, t (4;7) (q31;q22). In case 2, a women who had two spontaneous abortions and one stillborn fetus, the karyotype was 46, XX, t (3;15) (q12;p11.2), inv (5) (P13q13). The abnormal karyotype was not found in other chromosomes. Conclusions It is very important that couples with more than two miscarriages be provided with chromosomal analysis. Referring couples for karyotyping will rule out or confirm possible hereditary etiology and the source of chromosomal abnormalities in recurrent miscarriages.

Genetic Factors of Idiopathic Recurrent Miscarriage in Kazakh Population

“…Recurrent miscarriage (RM), classically defined as two or more spontaneous miscarriages up to 20 weeks of pregnancy, is a heterogeneous disorder affecting up to 3% of couples in the reproductive period ( 1 , 2 ). American Society for Reproductive Medicine (ASRM) considers that two consecutive pregnancy losses are sufficient for diagnosing RM so far as the recurrence rate and risk factors are similar to those observed after three losses ( 1 , 3 – 6 ).…”

“…There are publications that HLA complex suppresses maternal immune response required for implantation and in the presence of homogeneous histocompatibility complex (common for the mother and father) in inbred populations, the frequency of RM increases ( 20 ). The choice of polymorphisms of CTLA4 (rs-3087243, CT60 G/A) and CX3CR1 (rs3732379, Val249Ile) and genes of HLA DQA1, DQB1, and DRB1 (class II major histocompatibility complex) for the analysis of immune processes in iRM is statistically determined by their participation in T-cell tolerance and suppression of significant associations with RM according to GWAS data ( 2 ).…”

“…Numerous scientific studies indicate possible causes of RM; the common reasons are fetal chromosomal abnormalities, infectious agents, adverse environmental factors, bad habits, anatomical defects, thrombophilic disorders, and thrombotic disorders. However, RM causes in 50% of cases remain unknown ( 2 , 3 ). These RM cases do not have any explainable etiology and require in-depth etiopathogenesis investigation; thus, they are considered idiopathic RM (iRM).…”

Correction to: Recurrent spontaneous abortion related to balanced translocation of chromosomes: two case reports

“…Following publication of the original article [ 1 ], the authors identified an error in the affiliations 1–3.…”

“…The affiliations have been updated in the correction article and the original article [ 1 ] has been corrected.…”