Chromosome Changes
Studies show that most cases of primary ovarian insufficiency in adults are caused by gonadal dysgenesis in the absence or presence of Turner syndrome. [3] When adolescents have primary amenorrhea with no related diseases, abnormal karyotypes are discovered in over half of them. Over 13 percent of younger women (below 30 years) with secondary amenorrhea [4] also experience abnormal karyotypes. Although delays in puberty may be observed in affected women, it is initially noticed when tested for menstrual disorders. Some genetic conditions are responsible for primary ovarian insufficiency. Some of these conditions are when one normal X chromosome and one mutated X chromosome are present (mosaic Turner syndrome) and when the X chromosomes are weak and break (fragile X syndrome).