Current opportunities and new horizons into the genetic study of infertility

Abstract

Introduction: An estimated 12.5% of couples experiencing fertility problems and almost 12% of reproductive age women have turned to health services at least once due to infertility. First trimester miscarriage is the most common clinical manifestation of infertility associated with a genetic cause. Patients, Materials and Methods: The scientific research was conducted at A.S. Medical Center in Bucharest, Romania, between January 2016 and December 2018, on a representative group of 1264 Caucasian patients diagnosed with infertility, from which the study group was selected, consisting of 273 patients who were further genetically investigated. Results: Chromosomal instability, identified in 14% of patients, has been encountered most frequently in women (7%), and least often in fetuses (2%), unlike other chromosomal anomalies, identified in 55% of patients, which were more common in fetuses (27%) and least frequently in men (9%). Recurrent pregnancy loss due to genetic causes was identified in 53% of cases, being determined by chromosomal instability in 16% of cases and by other chromosomal anomalies in 37% of cases. Infertility due to a genetic cause was identified in 83% of cases, being determined by chromosomal instability in 17% of cases and by other chromosomal anomalies encountered in 66% of cases. In genetic risk pregnancies in evolution, fetal chromosomal anomalies were detected in 94% of cases, the most frequent being aneuploidy and polyploidy. Cytogenetic studies carried out on tissue fragments taken from aborted products of conception revealed the presence of a genetic cause in 57% of cases, an abnormal chromosome number being the most common (36%). The analysis of microdeletions of the long arm of the Y chromosome indicated that 5.5% of men with infertility are affected by this condition. Conclusions: Although genetic tests are considered complex and expensive laboratory investigations, they are crucial in identifying the etiology of over 40% of infertility cases associated with genetic factors, as well as in the correct and effective management of infertility.