Outcome of fetuses with Turner syndrome: a 10-year congenital anomaly register based study

To describe the characteristics and outcome of fetuses with Turner syndrome reported to a national congenital anomalies register.

All cases with a diagnosis of Turner syndrome reported to Congenital Anomaly Register and Information Service for Wales (CARIS) between 1 January 1998 and 31 December 2007 were included. The cases were grouped in five categories based on their outcomes: fetal loss (FL), termination of pregnancy (TOP), live birth (LB), and postnatal (PN) detection and comparison was undertaken between the groups.

One hundred twenty-four cases were reported during the study period. The prevalence of Turner syndrome was 1 in 4901 live female births. Seventy-four percent had 45 X karyotype while the rest had some form of Mosaic Turner karyotype. Pregnancy was terminated in 66% of antenatally diagnosed cases. FL and TOP groups had 92% and 87%, respectively, of 45 X karyotype - far greater than in the LB and PN groups. Increased nuchal thickness was the commonest anomaly noted in antenatal ultrasound and was a predictor for 45 X karyotype, FL, and termination.

Termination was the most common outcome of fetuses diagnosed antenatally with Turner syndrome. This has modified the natural history of Turner syndrome particularly in cases with Mosaic karyotype.