Background: The aim was to identify maternal risk factors in women giving birth to girls with Turner syndrome (TS) and to describe the characteristics of newborns with TS.
Methods: The Swedish Genetic Turner Register was cross-linked with the Swedish Medical Birth Register. Between 1973 and 2005, 494 children with TS were born. Maternal age, parity, height, smoking habits and neonatal characteristics; mode of delivery, gestational age, size at birth and Apgar score, were compared with women in the general population who gave birth to girls during the same period.
Results: More women with advanced maternal age (40+) delivered girls with TS, 3.2% when compared with 1.8% in the general population [OR 1.83, 95% confidence interval (CI) 1.09-3.08, after adjustment for year of birth]. Maternal height was inversely associated with TS pregnancies (P = 0.005). Late preterm birth occurred in newborns with TS in 10.5% when compared with 4.8% in the general population (OR 2.23; 95% CI: 1.67-2.97, after adjustment for year of birth and maternal age). Newborns with TS had birthweight less than -2SD in 17.8% and birth length less than -2SD in 21.0% when compared with 3.5 and 3.4%, in the general population (OR 6.55; 95% CI: 5.12-8.38 and OR 8.69; 95% CI: 6.89-10.97, after adjustment for year of birth and maternal age).
Conclusion: Advanced maternal age and short stature were risk factors for giving birth to a girl with TS. More TS girls were born late preterm and were smaller for gestational age than non-TS girls in the general population.