As of the beginning of this year, a blood glucose tolerance test to screen for gestational diabetes is being offered to all expectant mothers in Germany. The test is covered by the German statutory health insurance funds as a standard feature and is also part of the maternity guidelines. The combined efforts of internists and gynecologists shall lead to the prevention of elevated blood glucose levels during pregnancy and a reduced risk for certain birth complications.
In a new study, researchers at Tübingen University Hospital, a partner in the DZD, are also investigating the long-term consequences of gestational diabetes for mother and child. The study is being conducted by the Department of Internal Medicine IV (Medical Director Prof. Dr. Ulrich Häring) in collaboration with the Department of Gynecology and Obstetrics (Medical Director Prof. Dr. Diethelm Wallwiener) and also in close cooperation with other sites of the German Center for Diabetes Research (DZD) in Munich, Düsseldorf and Dresden. The large scale of the study shall ensure a sufficient number of study participants to obtain meaningful results.
If an expectant mother with gestational diabetes receives proper treatment, the pregnancy will progress normally without any complications and the woman will give birth to a healthy child, according to a press release of the Joint Federal Committee from March of this year (1). “We are pleased that this test is no longer performed only if gestational diabetes is suspected, but rather is a routine screening test for every patient in the 24th to 28th week of pregnancy,“ said PD Dr. Anita Hennige, senior physician in the Department of Internal Medicine at Tübingen University Hospital. Gestational diabetes can thus be detected at an early stage before complications occur.
Many women become very worried when the results of the glucose tolerance test are positive. However, treatment is relatively simple if the diagnosis has been made early on: “We know that the risk for mother and child can be reduced considerably through simple blood glucose tests and changes in the expectant mother’s diet. Drugs are only necessary in individual cases,” the diabetologist added.
Long-Term Consequences Possible
One long-term consequence for the mothers cannot be prevented with present-day treatment: Women who have gestational diabetes have a much higher risk of developing type 2 diabetes later on in life, although their blood glucose levels after childbirth were entirely normal again. The Tübingen researchers are seeking answers to the following questions: What determines whether women will develop diabetes after pregnancy? What risk factors are known? Is the diabetes due to insulin resistance or is there a lack of insulin?
Known risk factors are being overweight, type 2 diabetes mellitus in the family and certain genetic mutations. But there are also unknown factors. It is still unclear which woman in fact has an elevated risk and what she can do to reduce the risk. “Many of our patients are concerned about this issue after the birth of their children,” Dr. Hennige said. “In a few years we want to be able to predict the individual risk and give the women recommendations on how they can reduce their risk through lifestyle intervention.”
Fetal magnetoencephalography – Tubingen is one of two locations
But not only the mothers have a higher risk, the children of women with gestational diabetes are also at increased risk of developing diabetes early. “Besides genetic factors, environmental factors during pregnancy must also be considered,” said Dr. Hennige. “We think here of hormones from adipose tissue or dietary fats, which give the child a metabolic imprinting already in the womb.” This metabolic memory may lead to obesity and diabetes later on in life.
One way to investigate this fetal programming is fetal magnetoencephalography, which except for Tübingen is currently only available at one other location in the world. Using this non-invasive method the functional brain maturation of the fetus in women with gestational diabetes can be determined.
(1) Information leaflet published by the Joint Federal Committee:
„I am pregnant. Why are all pregnant women offered a test for gestational diabetes?” (German only)