ÖzetAmaç: Prematür over yetmezliği (POY) 40 yaşından önce gözlenen, 6 ay veya daha uzun süre adet görememe, serum folikül stimüle edici hormon yüksekli-ği ve düşük serum estradiol düzeyi ile tanımlanan bir durumdur. Bu çalışma-da amaç POY tanısı alan olgularda kromozom anomali tipleri ve sıklığı araş-
Anahtar KelimelerPrematür Over Yetmezliği; X Kromozom Anomalisi; Karyotip; Mosaism Abstract Aim: Premature ovarian insufficiency (POI) is characterized as amenorrhea for more than 6 months, occurring before the age of 40, with an increased follicle-stimulating hormone and low estrogen concentrations. The aim of our study is to determine the types and distribution of cytogenetic abnormalities among women with POI. Material and Method: The study is based on the retrospective karyotype analysis of 65 women with idiopathic POI referred to the Medical Genetics Department at the Bezmialem Vakif University Hospital. Results: Chromosomal abnormalities were present in 12 of 65 cases (18.4%). All of them had numerical abnormalities of the X chromosome. The most frequently detected abnormalities were X chromosome mosaicisms. Two cases had fragile X premutation carriers. Eight (12.3%) women were considered as familial POI. Discussion: Our results underline the essential role of the X chromosome in the etiology of POI. Therefore, regardless of clinical features and woman's age, cytogenetic investigations should be routinely performed in cases with POI.