New glucose tolerance test shows spike in incidence of gestational diabetes

COIMBATORE: The number of pregnant women diagnosed with gestational diabetes mellitus has doubled after the glucose challenge test was introduced in government hospitals two years ago. While this has led to government hospitals often facing an insulin shortage, gynaecologists say it has made protection of the foetus from the effects of gestational diabetes more effective.
In Coimbatore Medical College, 4 per cent, or 105 of 2,556 pregnant women tested between September 2013 and January 2014 were found to have diabetes. Doctors say this is a two to five-fold increase from the 1 to 2 per cent of women diagnosed earlier by conducting other tests. "Earlier, we used to do a simple blood sugar test for which the number of women testing positive were much lower," says Dr S Revwathy, dean, Coimbatore Medical College.
Though most women diagnosed with high blood sugar levels are prescribed new meal plans and simple physical exercises, many of them need insulin due to other complications. This along with increase in juvenile and type 1 diabetes often leaves government hospitals across the state short on glucose.
Pregnant women have been made to take the glucose challenge test (GCT) or Glucose Tolerance Test (GTT) over the last two years, which gynaecologists feel are a lot more effective. According to Federation of Obstetric and Gynaecological Societies of India (FOGSI), the numbers could be as high as 10%. This increase in numbers has led to most nursing homes and maternity clinics employing full time diabetologists.
"The numbers are definitely increasing, but they point towards better diagnosis rather than an increase in gestational diabetes in women," says gynaecologist and infertility expert Dr Kannagi Uthararaj. The Glucose Challenge Test is a method by which the patient is orally administered 50gms of glucose, told not to consume anything for the next one hour, and is then tested for blood sugar levels. Sugar levels above 140 indicate diabetes. The Glucose Tolerance Test (GTT) is a method by which a patient is administered anywhere between 75gms to 100gms of glucose and has their blood tested every hour for two or three hours. "These tests when done in the very initial stages of pregnancy help us prevent diabetes with dietary changes alone, which in turns protects the foetus" says Dr Uthararaj.
High blood sugar levels in a pregnant woman during the first trimester could lead to a range of serious complications such as development of foetal anomalies, premature lungs in new born babies leading to breathing difficulties and intra uterine foetal death, says Dr Asha Rao, director, Rao Hospital and Care. "It also helps us prevent conditions like foetal macrosomia, where the baby is more than 4 kg and glucose is considered toxic for the baby," says Dr Uthararaj.
Doctors recommend pregnant women undergo the GCT or GTT test every trimester of their pregnancy. "We usually manage their diabetes with just new meal plans. Only in extreme cases do we prescribe medication for patients," says Dr Rao.