Screening for hyperglycaemia in pregnancy: consensus and controversy

Policy decisions on whether to implement screening programmes depend on whether the proposed programmes meet a set of criteria laid down by the World Health Organization. Screening for hyperglycaemia in pregnancy (HGP) does not meet all the criteria. However the case for screening has been strengthened by a number of recent developments, including: rising prevalence of HGP because of increasing maternal age and BMI; the results of the Hyperglycaemia and Adverse Pregnancy Outcomes study, showing that adverse effects of HGP are seen over a wider range of plasma glucose levels than previously thought; two large trials which showed the benefits of treating lesser degrees of HGP; trials showing that metformin and glibenclamide were effective and safe alternatives to immediate insulin in those without good control on lifestyle measures alone. However uncertainties remain around the threshold for treatment, and on the best screening strategy.