Reduced fertility in women with X chromosome abnormality

Genomic markers of ovarian reserve

Ovarian reserve and its utilization, over a reproductive life span, are determined by genetic, epigenetic, and environmental factors. The establishment of the primordial follicle pool and the rate of primordial follicle activation have been under intense study to determine genetic factors that affect reproductive lifespan. Much has been learned from transgenic animal models about the developmental origins of the primordial follicle pool and mechanisms that lead to primordial follicle activation, folliculogenesis, and the maturation of a single oocyte with each menstrual cycle. Recent genome-wide association studies on the age of human menopause have identified approximately 20 loci, and shown the importance of factors involved in double-strand break repair and immunology. Studies to date from animal models and humans show that many genes determine ovarian aging, and that there is no single dominant allele yet responsible for depletion of the ovarian reserve. Personalized genomic approaches will need to take into account the high degree of genetic heterogeneity, family pedigree, and functional data of the genes critical at various stages of ovarian development to predict women's reproductive life span.

WITHDRAWN: A female autoimmunity gene exists: DDX3X

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Outcomes of spontaneous and assisted pregnancies in Turner syndrome: the U.S. National Institutes of Health experience

OBJECTIVE

To assess fetal and maternal outcomes of pregnancies in women with Turner syndrome (TS).

DESIGN

Retrospective case series.

SETTING

Clinical research center.

PATIENT(S)

276 adults with cytogenetically proven TS participating in an intramural natural history protocol.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Menstrual and obstetric histories, 50-cell karyotypes, and cardiovascular evaluation including aortic diameter measurements.

RESULT(S)

Our cohort included five women with spontaneous pregnancies and five with pregnancies using assisted reproduction (ART). All five women with spontaneous pregnancies had spontaneous puberty, despite 45,X in ≥90% of their 50-cell karyotype. Participants had a total of 13 pregnancies and 14 live births. One child had cerebral palsy; the others were chromosomally and developmentally normal. Delivery was by cesarean section in four out of seven spontaneous and six out of six ART-related pregnancies. One mother experienced preeclampsia in an ART-related twin pregnancy that required a preterm delivery; she has marked but stable aortic dilation years later.

CONCLUSION(S)

Approximately 2% of our study cohort experienced spontaneous pregnancies despite high-grade X monosomy, and a similar number achieved pregnancy via oocyte donation and ART. The potential for life-threatening cardiovascular complications warrants comprehensive screening before conception or single-embryo transfer, and caution regarding unintentional pregnancies for TS women.

Turner syndrome in a mother and daughter: r(X) and fertility

A patient with mosaic Turner syndrome and normal fertility had three documented pregnancies. She had a 45,X/46,X,r(X) karyotype and did not undergo spontaneous sexual maturation and menarche. Conception occurred while on hormone replacement therapy. Her first pregnancy ended with the birth of a normal 46,XY male, while the third pregnancy resulted in a healthy 45,X/46,X,r(X) female. A review of the literature reveals a myriad of theories to account for the variability of ovarian function in Turner syndrome, but, as yet, there are insufficient data to yield any conclusions. There appears to be an increased risk of trisomy 21 in the offspring of females with Turner syndrome.

Premature ovarian failure and ovarian autoimmunity

Premature ovarian failure (POF) is defined as a syndrome characterized by menopause before the age of 40 yr. The patients suffer from anovulation and hypoestrogenism. Approximately 1% of women will experience menopause before the age of 40 yr. POF is a heterogeneous disorder with a multicausal pathogenesis involving chromosomal, genetic, enzymatic, infectious, and iatrogenic causes. There remains, however, a group of POF patients without a known etiology, the so-called "idiopathic" form. An autoimmune etiology is hypothesized for the POF cases with a concomitant Addison's disease and/or oöphoritis. It is concluded in this review that POF in association with adrenal autoimmunity and/or Addison's disease (2-10% of the idiopathic POF patients) is indeed an autoimmune disease. The following evidence warrants this view: 1) The presence of autoantibodies to steroid-producing cells in these patients; 2) The characterization of shared autoantigens between adrenal and ovarian steroid-producing cells; 3) The histological picture of the ovaries of such cases (lymphoplasmacellular infiltrate around steroid-producing cells); 4) The existence of various autoimmune animal models for this syndrome, which underlines the autoimmune nature of the disease. There is some circumstantial evidence for an autoimmune pathogenesis in idiopathic POF patients in the absence of adrenal autoimmunity or Addison's disease. Arguments in support of this are: 1) The presence of cellular immune abnormalities in this POF patient group reminiscent of endocrine autoimmune diseases such as IDDM, Graves' disease, and Addison's disease; 2) The more than normal association with IDDM and myasthenia gravis. Data on the presence of various ovarian autoantibodies and anti-receptor antibodies in these patients are, however, inconclusive and need further evaluation. A strong argument against an autoimmune pathogenesis of POF in these patients is the nearly absent histological confirmation (the presence of an oöphoritis) in these cases (< 3%). However, in animal models using ZP immunization, similar follicular depletion and fibrosis (as in the POF women) can be detected. Accepting the concept that POF is a heterogenous disorder in which some of the idiopathic forms are based on an abnormal self-recognition by the immune system will lead to new approaches in the treatment of infertility of these patients. There are already a few reports on a successful ovulation-inducing treatment of selected POF patients (those with other autoimmune phenomena) with immunomodulating therapies, such as high dosages of corticosteroids (288-292).

Familial Turner syndrome

A 28-year-old Turner female with secondary amenorrhea is described, who showed 45,X/46,X,del(Xp) mosaicism in her blood lymphocytes and a 46,X,del(Xp) karyotype only in her ovaries. 45,X/46,XX mosaicism was found in the patient's mother, who presented short stature, mild Turner dysmorphism and had a normal reproductive life-span. Phenotypic implications of the cytogenetic findings in the patients are discussed, and literature data on fertility in Turner syndrome are briefly reviewed.

Distal long arm deletions of the X chromosome and ovarian failure

A mother and daughter are described with premature menopause and deletion of the X chromosome at q28.

Chromosome studies and fertility treatment in women with ovarian failure

In vitro fertilization and embryo transfer or gamete (or zygote) intra-Fallopian transfer after ovum donation were performed in 16 patients with primary or secondary amenorrhea, associated with chromosome abnormalities. The patients showed the wide range of (mostly X) chromosome abnormalities characteristic for women with primary or premature ovarian failure. Four of these patients became pregnant and three of them have delivered healthy infants with a normal karyotype. This pregnancy rate is far superior to the accepted fertility figure in these patients. When these results were compared with the fertility treatment results of three other groups of women with absent ovarian function (1. ovarian dysgenesis; 2. surgical castration; 3. premature menopause) but with a normal 46,XX karyotype, no difference in treatment efficiency could be detected. These results offer a promising approach for the treatment of infertility in agonadal patients with chromosome aberrations.