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Prenatal diagnosis of Turner syndrome: two clinical cases and
a retrospective analysis of detected cases on the basis of the Stavropol
Regional Clinical Consulting and Diagnostic Center from 2008 to 2018

Objective. The frequency of monosomy X is estimated. The diagnostic value of various ultrasound markers
in a fetus with Turner syndrome in the first and second trimesters of pregnancy was evaluated.
Materials. The database of cytogenetic studies from 2008 to 2018 of our center was analysed. Studies include
invasive prenatal diagnosis and research on abortion material. Two clinical observations of Turner's syndrome
identified in the second trimester of pregnancy were considered.
Results. Of 3450 cytogenetic studies, 70 karyotypes of monosomy X were detected, the full form was found
in 57 (81 %) cases, mosaic — 13 (19 %). The 46 karyotypes of monosomy X were non-developing pregnancies
and 24 cases of invasive prenatal diagnosis. In the group of non-developing pregnancies, the complete form of
monosomy X was observed in 40 (86.9 %) cases, mosaic — in 6 (13.1 %), embryo death in 73 % of cases occurred
in the period of 8–9 weeks of gestation. The data of two clinical observations of Turner syndrome identified in
the second trimester are presented. The finding ultrasonic markers of monosomy X in the analysed studies are
considered.
Conclusion. The detection of monosomy X is possible in most cases in the first trimester. However, the variability of symptoms and their severity does not always allow identify this pathology in the early stages. The search
for soft markers during the second trimester ultrasound, the widespread use of echocardiography and a comprehensive assessment of all the studies performed can increase the frequency of detection of Turner syndrome.