Spontaneous Pregnancy in Mosaic Turner syndrome: Case Report and Recent Insights for Genetic and Reproductive Counselling
TS (Turner Syndrome) prevalence has been reported with an incidence of 1 in 2500 live births and is one of the most common chromosomal abnormalities worldwide . The classic form of Turner syndrome is associated with a 45,X karyotype, accounting for approximately half of all cases. Twenty-five (25%) have a partial deletion of one X chromosome and 20% carry varying degrees of mosaicism, most commonly a 45,X/46,XX karyotype . A majority of women with Turner syndrome develop accelerated follicular atresia that predisposes them to primary amenorrhea, premature ovarian failure, and infertility later on in their lives. Mosaic cases have milder phenotypic features compared to pure 45, X cases and may show normal pubertal development and regular menstruation. In that case, the diagnosis is often established later than in the pure form of Turner syndrome, while timely fertility counselling and exploration of fertility preservation options are crucial. Furthermore, TS patients’ pregnancy is associated with high risks of maternal mortality due to cardiovascular and metabolic complications, spontaneous abortion, and karyotype abnormalities of the fetus. Cases of pregnancy in mosaic TS are rare, and most of the knowledge concerning reproductive and obstetric outcomes relies on case reports and case series .