Ovarian deficiency or hypoplasia

Congenital ovarian hypoplasia is caused by the lack of an X chromosome in women, such as short stature, primary amenorrhea, webbing, and elbow eversion. The incidence of this type is much lower than the previous type, accounting for 0.64% of women's mental retardation. Its clinical characteristics are female appearance, short body, second characteristic dysplasia, lack of ovaries and infertility. Some patients have mild mental retardation. Some patients have congenital malformations such as heart, kidney, and bones. The disease was reported by Turner in 1938, so it is called Turner syndrome. In 1959, Ford et al. Confirmed that the etiology of sex chromosome X was monotonic. The patient's gonad development disorder, the ovary was replaced by a strip-shaped fibrous tissue. The phenotype of Turner syndrome is that women account for about 0.4 ‰ of live births. The low incidence is because embryos of the X monomer are difficult to survive, and abortion occurs in about 99% of cases. The disease is also the only surviving monomer syndrome in humans.