Turner syndrome: contemporary thoughts and reproductive issues.

Turner syndrome is a common genetic disorder that has been classically associated with a 45,X karyotype. Several X-chromosomal abnormalities have been identified in these patients, many of which involve mosaicism. These patients have variable but predictable phenotypic findings and are at risk for development of endocrine, autoimmune, and structural abnormalities. As many as 1.5% of the population with Turner syndrome may develop dissection and rupture of the ascending aorta; the presence of abnormalities of the cardiac tree and hypertension increase this risk, but their absence does not preclude it. Rupture has occurred at aortic diameters smaller than previously reported for other patient populations. Five percent or more of women with Turner syndrome may have abbreviated menstrual function before developing amenorrhea and hypergonadotropic hypogonadism. An estimated 1 to 2% of all patients may become pregnant. Only three patients with Turner syndrome (and two of them with streak ovaries) have ever been reported to become pregnant after developing amenorrhea and elevated gonadotropin levels. Pregnancy, either spontaneous or more commonly from donor oocyte, increases maternal mortality rate for these women by an estimated ≥100 fold. It appears that all Turner women are at risk of rupture; neither prior spontaneous menses nor age >30 years provides protection. In addition, the literature suggests that the physiological changes of pregnancy may increase the risk of rupture in future years after delivery for those Turner women who seemingly made it safely through pregnancy. The use of the term PRIMARY OVARIAN INSUFFICIENCY (POI) for Turner syndrome gives me some discomfort. For women with 46,XX hypergonadotropic hypogonadism, POI accurately provides the suggestion that follicular depletion is often not complete (although remissions are usually self-limiting and the vast majority of patients will not spontaneously become pregnant). I clearly understand the need to prevent any stigmatization to patients unfortunately diagnosed with premature oocyte depletion, and I believe that the use of the diagnosis POI leaves the door open for the occurrence of reproductive function and for the 5 to 10% of 46,XX patients who may spontaneously become pregnant. However, the world literature reports only two women with Turner syndrome, hypergonadotropic amenorrhea, and streak ovaries who have ever become pregnant spontaneously after their diagnosis. It would be unfair to such women with Turner syndrome to give them the same hope for pregnancy as we do for women with 46,XX POI. Amenorrheic women with Turner syndrome truly have ovarian failure. Although I have adopted the term POI in this article for women with Turner syndrome, semantics are no substitute for honest, thorough, and compassionate counseling.