Stratification of Risk of Diabetes in Early Pregnancy

High glucose level in Pregnancy or Gestational Diabetes Mellitus (GDM) is one of the most common medical conditions during pregnancy. When undetected, it can cause significant harm for the pregnant women and her offspring. GDM can affect 5-25% of all pregnant women. It depends on the population and where the boundary is drawn between normal and abnormal glucose levels.

Certain ethnic minority groups are considered at high-risk for developing GDM, including Indians. It is estimated >15% of pregnancies are affected by GDM in India. The immediate risks of untreated GDM are high rates of pre-eclampsia, higher caesarean section rates and psychological effects such as anxiety and depression. Women who develop GDM have a 7-8 times higher life-time risk of type 2 diabetes (T2D). Similarly, the immediate risks to the children are being too big or too small, shoulder damage during labour, low glucose levels or jaundice at birth, difficulty in breathing and in rare cases stillbirth. In the long term, the risk of obesity and T2D is also higher.

The diagnosis of GDM is usually made between 24-28 weeks of pregnancy using a glucose drink test called oral glucose tolerance test (OGTT). Although treatment can improve the outcomes, some of the damage may have already been done before the detection of GDM. Therefore, screening to detect high glucose level in pregnancy seems beneficial. However, there can be harms as well as benefits in screening programmes. Therefore a balance should be achieved between identifying women whose blood glucose level is high enough to cause harm and those with glucose level that would not cause harm. Currently, it is recommended that all pregnant women should be screened for GDM if they belong to a high-risk ethnic population. However, conducting OGTT in India is challenging, as this test requires pregnant women present themselves to a laboratory facility in a fasting state.

In many countries, women are selected for OGTT based on the presence of at least one of the high risk factors such as higher body weight, older age and family history of T2D. However, this selection method can miss up to 50% of women who may develop GDM. The aim of the study is to develop a risk score in early pregnancy based on a combination of these risk factors that can be collected easily along with a simple finger prick average blood glucose test (called HbA1c). The efficiency of different levels of this combined risk score will be tested against the risk of developing GDM in the later part of pregnancy.

Cost effectiveness analysis will also be conducted to identify at what risk level screening can be recommended in India. An accurate score that can safely exclude women at low risk of developing GDM will have significant benefits to the pregnant women. They can be safely reassured. Avoiding the need for OGTT will have significant time and cost benefits. In contrast, if the score identifies them as at high-risk, healthy eating and appropriate life style advice can reduce their risk of developing GDM in later pregnancy.