Pre- and perinatal aspects of sex chromosome abnormalities and other gonadal dysgeneses

Introduction: Sex chromosome aberrations (SCAs) and other gonadal dysgeneses (OGDs) compose a huge part of disorders of sex development (DSD), but a comprehensive pre- and perinatal picture of this wide spectrum is missing. Our aim was to support genetic counseling with evidence, and improve the feasibility of personalized medicine, genotype-phenotype specific clinical practice, management, and prevention of complications. Clinical data: We collected the pre- and perinatal data of 137 patients, who were diagnosed with SCAs and OGDs between 2009 and 2019 at the Genetic Division of Semmelweis University’s 2 nd Department of Pediatrics, Hungary. Methods: : Data of patients were systemized and analyzed according to karyotype, which involved the relative prevalence, risk factors, prenatal signs and genetic tests, possible perinatal complications, and suggestive neonatal signs. We reviewed the recent scientific literature in relation to SCAs and OGDs. Results: : Relative ratio of Turner, Klinefelter, Triple/Poly X and Double Y syndromes was 4:2:1:1. Diagnostic prenatal tests (DPTs) were performed in 18%, mostly due to advanced maternal age. Four patients were conceived with in vitro fertilization (IVF). 20% of mothers were older than 35, whereas 18% of fathers were over 40 years of age. 25% of patients were premature, only one tenth had suggestive neonatal signs. Without prematures, 6% of the cohort had low and 3% had high birth weight, whereas 2% had low and 24% had high birth length. The main reason underlying the high prevalence (28%) of cesarean section (CS) was abnormal fetal development. Discussion: Advanced parental ages and IVF increase the risk for SCAs and OGDs, which are important to recognise in time because certain forms predispose to prematurity, abnormal somatic growth, perinatal complications and the need for CS. The diagnostic efficacy of SCAs and OGDs is poor due to the lack of prenatal ultrasound signs and characteristic neonatal symptoms, which could be offset by including paternal age in prenatal risk assessment and the further spread of noninvasive prenatal testing (NIPT).