Balanced Autosomal Translocations in Two Women Reporting Recurrent Miscarriage

Spontaneous abortion or loss of fetus prior to 20 weeks of gestation is observed in 15-20% of clinically recognized pregnancies. Recurrent Miscarriage (RM) is defined as three or more consecutive pregnancy losses and it affects 1-2% of women. Parental chromosomal rearrangements account for 2-5% of RM. This report describes two couples with a clinical history of RM who were subjected to conventional cytogenetic analysis to ascertain the chromosomal aetiology. Analysis of GTG-banded metaphases obtained from cultured lymphocytes at approximately 500-band resolution revealed balanced translocation in the female spouses as 46,XX,t(8;11)(p11.2;q23.3) in BR27W and 46,XX,t(5;7)(p15.1;q32) pat in BR49W. Both the male partners exhibited 46,XY karyotype. Fluorescent In Situ Hybridization (FISH) analysis was subsequently carried out to confirm the balanced translocation using suitable whole chromosome paint probes. These balanced chromosomal abnormalities in the parents could be responsible for the repeated fetal losses. Hence, karyotype analysis should be a mandatory etiological investigation for couples with RM towards genetic counselling. Disruption of critical genes through these rearrangements could also underlie the pregnancy outcome.