Universal versus selective risk factor-based screening strategy for gestational diabetes mellitus

Date of Award


Document Type


Degree Name

Master of Medicine (MMed)


Obstetrics and Gynaecology (East Africa)


Background: Gestational hyperglycaemia is associated with a higher incidence of adverse maternal and fetal outcomes than is seen in normal pregnancy. Untreated gestational diabetes mellitus (GDM) has an increased perinatal morbidity and mortality. Morbidity related to macrosomia includes shoulder dystocia with birth injury and perinatal asphyxia in the fetus. In the mother, macrosomia is a risk factor for genital tract injury, obstructed labour, uterine atony and increased risk of Caesarean section. Long term sequelae in the baby include obesity, development of type 2 diabetes mellitus, intellectual and neurological developmental problems. For the mother, GDM is a very strong risk factor for the development of type 2 diabetes later in life. Published studies show that after GDM, 35-60% of women develop type 2 diabetes within 10 years. Therefore it is prudent that gestational diabetes is diagnosed and appropriate treatment and monitoring instituted. Screening is an important component of the diagnostic process.

Objectives: To compare detection rates of the universal to the selective risk factor-based screening strategy for gestational diabetes mellitus.

Methodology: A prospective cross-sectional study involving 185 participants consecutively recruited at or less than 28 weeks gestation . All participants had their risk factors for gestational diabetes identified and recorded at the beginning of the study then underwent the 50g oral glucose challenge screening test. Detection rates and prevalence of universal and selective strategies were calculated and compared. An exploratory analysis of risk factors was also done.

Results: The Prevalence of an abnormal screening test in the sample with risk factors was 12.0% (95% CI: 6.0%, 17.9%) and in the sample without risk factors it was 19.1% (95% CI: 9.5%, 28.7%).

Conclusion: Overlap of confidence intervals indicates no evidence of a difference between the screening strategies. However despite the non-significant, higher detection rates by the universal strategy, clinical practice safety demands that as many cases of gestational diabetes as possible are detected because of adverse clinical correlates hence justifying universal screening.

This document is available in the relevant AKU library