PhD defence: Ivonne Bedei
New research strengthens prenatal counselling for Turner syndrome
Info about event
Time
Location
The auditorium and Aarium at MOMA, Aarhus University
On Friday 18 September 2026 at 14:00, Ivonne Bedei defends her PhD dissertation entitled “Turner Syndrome – early detection, qualified prenatal counselling, prediction of phenotype and outcome”.
Turner syndrome varies considerably before and after birth, and both genetic findings and ultrasound features influence the course of pregnancy. A new PhD project from Aarhus University, Health, examines how prenatal testing, chromosomal variation and the fetal phenotype can support more precise counselling for pregnant women and their families.
Turner syndrome results from the complete or partial absence or alteration of one X chromosome. It encompasses classic monosomy X, mosaic karyotypes, and structural abnormalities of the X chromosome. The genetic, epigenetic, and clinical diversity makes it difficult to predict the course of an individual pregnancy.
The PhD project examines Turner syndrome from several complementary perspectives. The studies investigate which karyotypes are identified following non-invasive prenatal testing (NIPT), confirm that screening results should be confirmed by diagnostic testing, examine how genetic findings and ultrasound features relate to pregnancy outcome, and describe small omphalocele as a new phenotype in fetuses with the karyotype 45,X in early pregnancy. A central dataset is a large German nationwide cohort of pregnancies with a prenatal diagnosis of Turner syndrome.
The findings show that prenatal Turner syndrome should not be regarded as a single uniform condition. The fetal phenotype and the specific chromosomal variant provide different, complementary prognostic information. Marked ultrasound abnormalities, such as cystic hygroma or hydrops, are associated with a high risk of fetal death. In contrast, fetuses with "other" anomalies or findings and mosaic and some structural X-chromosome variants often have a milder prenatal course. However, the absence of severe ultrasound abnormalities cannot predict all health outcomes that may emerge later in life.
The project emphasises the need to distinguish screening from diagnosis, to interpret NIPT results cautiously, and to base counselling on an integrated assessment of karyotype and serial ultrasound findings. The uncertainty about the prenatal course and the postnatal phenotype should be included in prenatal counselling. The aim is to provide families with more nuanced information while recognising the substantial variation between individuals.
The summary is written by the PhD student.
The defence is public and takes place in the auditorium and atrium at MOMA, Aarhus University. Please see the press release for more information.
Contact
PhD student Ivonne Bedei
Mail: ivonne.bedei@clin.au.dk
Phone: 004964198559109