Mechanism of recurrent spontaneous abortions in women with mosaicism of X-chromosome aneuploidies.
OBJECTIVE
To investigate the mechanism of recurrent miscarriages in women with mosaicism of X-chromosome aneuploidies.


METHODS
Prospective case-control study.


METHODS
University-based reproductive clinic housed in a medical center with genetic laboratories.


METHODS
Eighteen women who experienced recurrent miscarriages and had mosaicism of X-chromosome aneuploidies; two control groups, one with a balanced structural autosomal rearrangement and the other without chromosomal abnormalities.


METHODS
Criteria were established for the diagnosis of low-grade X-chromosome mosaicism by using peripheral blood lymphocytes. Patients were evaluated for the pathogenesis of recurrent miscarriages. Their abortion rate was assessed, and each abortus was karyotyped.


METHODS
Abortion rate and karyotype of the abortus.


RESULTS
In comparison with patients with X-chromosome mosaicism with a balanced structural autosomal rearrangement, patients with X-chromosome mosaicism without a balanced autosomal structural rearrangement had a significantly higher incidence of diminished ovarian reserve (DOR) and had a somewhat higher prevalence of uterine anomalies. In comparison with controls without chromosomal abnormalities, the patients with a balanced autosomal structural rearrangement also had higher incidence of both conditions, but the differences were not statistically significant. At least two factors are implicated in recurrent miscarriages in women with X-chromosome mosaicism. Among them, DOR is the most prevalent (occurring in 44.4% of cases), followed by uterine anomalies (16.7% of cases). Cases with DOR had a higher abortion rate than did those without (68.6% vs. 44.1%). Cases with DOR also had a slightly higher rate of abnormal karyotypes in the abortus than did those without (73.7% vs. 42.9%).


CONCLUSIONS
The oocytes of women with X-chromosome mosaicism are in a suboptimal state of development and are prone to embryonic lethality.
Kuo
Pao-Lin
PL
Department of Obstetrics and Gynecology, National Cheng-Kung University Medical College, Tainan, Taiwan, Republic of China. paolink@mail.ncku.edu.tw
Guo
How-Ran
HR
D000026:Abortion, Habitual / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology*; D000328:Adult; D000782:Aneuploidy; D016022:Case-Control Studies; D041321:Chromosomes, Human, X; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007621:Karyotyping; D009030:Mosaicism; D010053:Ovary / Q000503:physiopathology; D011446:Prospective Studies; D012098:Reproduction; D014599:Uterus / Q000002:abnormalities