alpha-thalassaemia trait and gestational diabetes mellitus in Hong Kong

Aims/hypothesis. The purpose of this study was to examine the association b etween maternal alpha -thalassaemia trait and the occurrence of gestational diabetes mellitus in at-risk Chinese women in Hong Kong. Methods. From 3320 pregnant women who had delivered in our hospital and und ergone the oral glucose tolerance test for various risk factors over a thre e-year period, 163 with alpha -thalassaemia trait were identified (study gr oup). The control group consisted of 163 women chosen from the next patient that was matched for maternal age and parity, following each index case. C omparison was made in the incidence of gestational diabetes mellitus define d by the World Health Organisation criteria, obstetric complications, and p erinatal outcome. Results. The incidence of gestational diabetes mellitus was higher in the s tudy group (62.0% vs 14.7%, p < 0.0001) which had a higher pre-pregnancy bo dy mass index and lower haemoglobin concentrations. Although more patients in the study group had risk factors (41.7% vs 26.4%, p = 0.003), there was no difference in the pregnancy outcome or perinatal complications. Among th e gestational diabetic women, those with ct-thalassaemia trait were conside rably younger and their infants had lower body mass index but there was no significant difference in the outcome. On multiple logistic regression anal ysis, the alpha -thalassaemia trait remained an important factor in the dia gnosis of gestational diabetes (OR 11.74, 95% CI 6.37-21.63). Conclusion/interpretation. Among women at risk of gestational diabetes, the presence of the ct-thalassaemia trait is an additional risk factor for ges tational diabetes mellitus.