The Rate of Sex Chromosome Aneuploidies in Prenatal Diagnosis and Subsequent Decisions in Western Turkey

Abstract

Sex chromosome abnormalities (SCAs) are the most common genetic disorder with a frequency of 1/400 or 1/500 live births. In this study we aimed to evaluate the initial indications, frequencies, and pregnancy termination rates of pregnancies with SCAs referred to Ege University Medical Faculty, Department of Medical Genetics. Prenatal diagnosis was performed in 7505 cases in the period of January 1998 through December 2009. In this study, their initial indications and fetal karyotype results were evaluated retrospectively. A total of 60 pregnancies (0.80%) with SCA were evaluated. Turner syndrome was the most commonly diagnosed SCA in prenatal diagnosis (60%). The most common referral reason for pregnancies with Turner syndrome was cystic hygroma on ultrasonography. Of 14 pregnancies having a prenatal diagnosis with SCA (Turner syndrome: 7, Klinefelter syndrome: 5, Mosaic Turner syndrome: 2), 12 with SCA (85.7%) were terminated. The ratio of SCA in the prenatally diagnosed cases was similar to those reported in the literature. Although the ratio of terminated pregnancies with Turner syndrome was similar to those reported from European countries, all the pregnancies with Klinefelter syndrome have chosen termination, which showed a regional difference in Turkey. It is important to consider the decisions of the families during the genetic counseling sessions of the couples having SCAs.