Should we screen for gestational diabetes? The case for screening for gestational diabetes

Introduction

Screening for gestational diabetes is imperative but we need to refocus away from short term improvements in obstetric outcomes to more important medium and long term health benefits. Today 5% of United Kingdom1 and 12% of United States2 total healthcare expenditure is spent on diabetes and its complications. There is a global epidemic of non-insulin dependent diabetes, and radical preventive measures are required if morbidity and mortality from diabetes are to fall. We would ask whether we can afford not to screen for gestational diabetes.

Identifying future diabetics

Detecting gestational diabetes identifies women at risk of future non-insulin dependent diabetes.3 4 The success of treating non-insulin dependent diabetes is severely hampered by the high percentage of diabetic complications present at diagnosis,5 so earlier diagnosis is important in preventing complications.6 Half of all people with non-inuslin dependent diabetes are clinically undiagnosed, and diagnosis takes, on average, seven years from onset of the disorder.7

The rate of progression to non-insulin dependent diabetes mellitus after a pregnancy where the woman has had gestational diabetes depends predominantly on ethnicity and the degree of glucose intolerance both in pregnancy and immediately afterwards.8 Other contributing factors are weight during pregnancy and subsequent weight gain, age, parity, and family history.8 9 In high risk populations, such as Hispanic American women, about 40% of women with gestational diabetes develop diabetes within six years, which rises to 70% among those with impaired glucose tolerance (by World Health Organisation criteria) after birth.10 In white Europeans the rate of progression to diabetes is slower—20-40% within 20 years.11 Identifying women who are at risk while they are still young provides an opportunity to identify the disease in subsequent pregnancies and to modify the natural …