Pregnancy in patients with Turner's syndrome: six new cases and review of literature

Poor uterine development in Turner syndrome with oral oestrogen therapy

OBJECTIVE

To evaluate uterine development in Turner syndrome (TS) patients in relation to treatment with oral ethinyl oestradiol (E2 ) for pubertal induction.

DESIGN AND PATIENTS

Pelvic ultrasound data for 96 TS patients scanned since 1989 were analysed. Patients were classified into three groups: (1) untreated (n = 48); (2) complete spontaneous puberty (n = 10); and (3) treated with ethinyl oestradiol (n = 38). Uterine development was described in the three groups and compared with the normal data.

MEASUREMENTS

Uterine length, fundal-cervical ratio (FCR) and shape were recorded, and presence or absence of ovaries noted. In the treated group, cross-sectional and longitudinal data were combined to compare uterine development with Tanner breast stage.

RESULTS

In untreated girls up to age 10 years there was a variable distribution of uterine length and FCR about the mean. Thereafter, the uterus failed to grow and mature normally. Girls with complete spontaneous puberty had morphologically normal ovaries and uteri, but of 7 girls who attained menarche, 3 subsequently developed secondary oligomenorrhoea or amenorrhoea. In the treated group, in general, breast development and uterine length progressed with increasing E2 dose. However, only 50% of girls with complete secondary sexual development had a mature heart-shaped uterine configuration.

CONCLUSIONS

Our current E2 treatment regimen for TS girls gives rise to satisfactory pubertal induction and maintenance, but failed to induce a fully mature uterus in half the cohort. In view of the high risk of miscarriage in TS in both spontaneous and assisted pregnancies, the effect of more physiological methods of E2 replacement on uterine development should be investigated.

Turner's syndrome in adulthood

Turner's syndrome is the most common chromosomal abnormality in females, affecting 1:2,500 live female births. It is a result of absence of an X chromosome or the presence of a structurally abnormal X chromosome. Its most consistent clinical features are short stature and ovarian failure. However, it is becoming increasingly evident that adults with Turner's syndrome are also susceptible to a range of disorders, including osteoporosis, hypothyroidism, and renal and gastrointestinal disease. Women with Turner's syndrome have a reduced life expectancy, and recent evidence suggests that this is due to an increased risk of aortic dissection and ischemic heart disease. Up until recently, women with Turner's syndrome did not have access to focused health care, and thus quality of life was reduced in a significant number of women. All adults with Turner's syndrome should therefore be followed up by a multidisciplinary team to improve life expectancy and reduce morbidity.

Genetic analysis of mosaicism in 53 women with Turner syndrome

Mosaicism involving the sex chromosomes is a common finding in women with Turner syndrome (TS). It is especially important to detect Y-chromosomal material, since this is a risk factor for the development of gonadoblastoma. Recent studies have also indicated that the frequency of 45,X cells may be used to predict prognosis. As part of an ongoing multi-disciplinary study, we have examined the extent of Y-chromosomal material and sex chromosomal mosaicism and its tissue specificity in 53 women with TS. The results of lymphocyte karyotyping were compared with the use of interphase X/Y fluorescence in situ hybridisation (FISH) analysis of lymphocytes and buccal mucosal cells. As could be expected, an extended FISH analysis detected more Y-chromosomal material than karyotyping (in 15% vs. 11% of the women, respectively) and also detected more X-chromosomal mosaicism among the TS women (in 70% vs. 45 % of the women, respectively). In half of the women, tissue-specific differences between lymphocytes and buccal mucosal cells were found. Based on these results, we suggest the use of X/Y interphase FISH as a complement to karyotyping in order to obtain a more complete knowledge of the chromosome constitution of each individual with TS.

Fertility and pregnancy outcome in Danish women with Turner syndrome

The aim of the investigation was to study fertility in Danish women diagnosed with Turner syndrome (TS), and to describe their offspring. In total, 410 women in the fertile age were registered in the Danish Cytogenetic Central Register with TS between January 1973 and December 1993. Their karyotype were as follows: 49% with 45,X, 23% with mosaicism and a structural abnormality of the second X, 19% with 45,X/46,XX mosaicism, and 9% with 46,XX and a structural abnormality of the second X. Thirty-three women, one with 45,X, 27 with mosaicism and 5 with 46,XX and a structural abnormality of the second X, gave birth to 64 children. Two women had become pregnant after in vitro fertilization, including a woman with 45,X after an egg donation. Thus, 31 women(7.6%) had achieved at least one spontaneous pregnancy, but 48% of the fertile women registered with 45,X/46,XX had 45,X in less than 10% of the analysed cells. Twenty-five of the 64 children had a chromosome analyzed. Six of the 25 examined children, including three siblings, had chromosomal aberrations. No case of Down's syndrome was present, and only two children had malformations. Fertility in women registered with TS is higher than earlier reported. However, only women with 45,X/46,XX mosaicism or 46,XX and structural abnormality of the second X, gave birth to live children after spontaneous pregnancies.

Phenotype, ovarian function, and growth in patients with 45,X/47,XXX Turner mosaicism: implications for prenatal counseling and estrogen therapy at puberty

OBJECTIVE

Our objective was to determine whether girls with the rare Tur-ner 45,X/47,XXX mosaic karyotype are less severely affected than girls with 2 commoner karyotypes.

STUDY DESIGN

We evaluated growth status, phenotype, and ovarian function in 7 girls with 45,X/47,XXX mosaicism, age-matching each with 2 girls with 45,X and 1 with 45,X/46,Xi(X)(q10) karyotypes.

RESULTS

For the index, 45,X, and 45,X/46,Xi(X)(q10) groups, respectively, the median/mean height SD score at the start of growth hormone therapy/comparable age was -2.0 (-1.2), -2.3 (-2.4), and -2.6 (-2.6), cardiac anomalies were identified in 0 of 7, 4 of 14, and 1 of 7, renal abnormalities in 0 of 7, 4 of 14, and 3 of 7, middle ear problems in 2 of 7, 11 of 14, and 4 of 7, and special educational needs in 0 of 7, 3 of 14, and 1 of 7. Complete spontaneous puberty with menarche was seen in all but 1 girl older than 12 years in the index group compared with only 1 girl in the comparison groups. Ovarian tissue was identified in 6 of 7, 0 of 14, and 1 of 7 girls, and the mean follicle-stimulating hormone was 6, 25, and 21 U/L, respectively.

CONCLUSION

Girls with 45,X/47,XXX karyotype are mildly affected, with good preservation of ovarian function. This result has important implications for prenatal counseling and the need for estrogen therapy at puberty.

Turner's syndrome

Before chromosomal analysis became available, the diagnosis of Turner's syndrome was based on the characteristics independently described by Otto Ullrich and Henry Turner, such as short stature, gonadal dysgenesis, typical, visible dysmorphic stigmata, and abnormalities in organs, which present in individuals with a female phenotype. Today, Turner's syndrome or Ullrich-Turner's syndrome may be defined as the combination of characteristic physical features and complete or part absence of one of the X chromosomes, frequently accompanied by cell-line mosaicism. The increasing interest in Turner's syndrome over the past two decades has been motivated both by the quest for a model by which the multi-faceted features of this disorder can be understood, and the endeavour to provide life-long support to the patient. New developments in research allow patients with Turner's syndrome to have multidisciplinary care.

Short stature in a mother and daughter caused by familial der(X)t(X;X)(p22.1-3;q26)

Deletions of the terminal Xp regions, including the short-stature homeobox (SHOX) gene, were described in families with hereditary Turner syndrome and Léri-Weill syndrome. We report on a 10-2/12-year-old girl and her 37-year-old mother with short stature and no other phenotypic symptoms. In the daugther, additional chromosome material was detected in the pseudoautosomal region of one X chromosome (46,X,add(Xp.22.3)) by chromosome banding analysis. The elongation of the X chromosome consisted of Giemsa dark and bright bands with a length one-fifth of the size of Xp. The karyotype of the mother demonstrated chromosome mosaicism with three cell lines (46,X,add(X)(p22.3) [89]; 45,X [8]; and 47,X,add(X)(p22.3), add(X)(p22.3) [2]). In both daughter and mother, fluorescence in situ hybridization (FISH), together with data from G banding, identified the breakpoints in Xp22.1-3 and Xq26, resulting in a partial trisomy of the terminal region of Xq (Xq26-qter) and a monosomy of the pseudoautosomal region (Xp22.3) with the SHOX gene and the proximal region Xp22.1-3, including the steroidsulfatase gene (STS) and the Kallmann syndrome region. The derivative X chromosome was defined as ish.der(X)t(X;X)(p22.1-3;q26)(yWXD2540-, F20cos-, STS-, 60C10-, 959D10-, 2771+, cos9++). In daughter and mother, the monosomy of region Xp22.1-3 is compatible with fertility and does not cause any other somatic stigmata of the Turner syndrome or Léri-Weill syndrome, except for short stature due to monosomy of the SHOX gene.

A case of 45,X Turner syndrome with spontaneous ovulation proven by ultrasonography

A well-documented case of non-mosaic Turner syndrome, with spontaneous pubertal development and ovulatory cycles is reported. Mosaicism could be excluded both by karyotyping of 172 metaphases of blood lymphocytes and fibroblasts, and by fluorescence in situ hybridization, using an X-centromeric probe, in 200 blood lymphocyte nuclei. This Turner syndrome patient underwent normal pubertal development, with spontaneous menarche at 14 years, followed by regular monthly periods. Hormonal measurements performed during puberty were consistent with the patient's pubertal development. At the age of 26 years the patient was referred for complete fertility evaluation. Detailed hormonal analyses were performed in a given cycle. They showed midluteal phase estradiol and progesterone values within the range corresponding to normal ovulation and corpus luteum function. In the same cycle, pelvic ultrasonography was also performed at days 13, 15 and 18. It demonstrated a spontaneous ovulation, with follicular rupture that occurred between days 15 and 18. This is the first report of a spontaneous ovulation in Turner syndrome evidenced, not only by hormonal analysis, but also by ultrasonographic demonstration of follicular rupture.

Turner's syndrome and pregnancies after oocyte donation

A total of 20 clinical pregnancies was achieved among 18 women with Turner's syndrome who were treated in an oocyte donation programme. The oocytes were donated by voluntary unpaid donors. A mean of 1.8 embryos per transfer was given to each recipient by way of 28 fresh and 25 frozen embryo transfers. With fresh and frozen embryos, 13 and seven pregnancies respectively were achieved. The clinical pregnancy rate per fresh embryo transfer was 46%, and the implantation rate 30%, being similar to the corresponding rates among our oocyte recipients with primary ovarian failure in general. The corresponding rates with frozen embryos were 28 and 19%. Of these pregnancies, 40% ended in miscarriage. This high rate may be explained by uterine factors. Six women were hypertensive during pregnancy, a rate comparable with that in other oocyte donation pregnancies. All these women delivered by Caesarean section. Pregnancy and implantation rates after oocyte donation were high in women with Turner's syndrome, but the risk of cardiovascular and other complications is high. Careful assessment before and during follow-up of pregnancy are important. Transfer of only one embryo at a time to avoid the additional complications caused by twin pregnancy is recommended.