Shining a Light on Gestational Diabetes: An interview with Dr Jana Koporcová

Shining a Light on Gestational Diabetes: An interview with Dr Jana Koporcová

Gestational diabetes (GDM) is a metabolic disorder that can develop during pregnancy in women who don't already have diabetes. Managing gestational diabetes can help ensure you have a healthy pregnancy and a healthy baby. Every year, an average of 7% of pregnancies in the world are affected by gestational diabetes. We spoke with Dr Jana Koporcová from Unilabs Slovakia to gain deeper insights into the condition and the importance of early detection.

Can you explain what gestational diabetes is and how it differs from other types of diabetes?

Gestational diabetes mellitus (GDM) is a disorder of glucose metabolism and represents one of the four main types of diabetes. GDM is usually first detected in the second or third trimester of pregnancy, in women who have not previously had diabetes. This disorder typically subsides after the puerperium (in the first six weeks after giving birth). After this six-week period, women with GDM should have a repeat oral glucose tolerance test (oGTT) within three to six months after delivery. 

What are the key risk factors for developing GDM, and why is early screening important?

Pregnancy is accompanied by significant changes in the metabolism and sensitivity of the mother's body to insulin. The probability of developing GDM increases with the presence of risk factors such as being overweight, a lifestyle with minimal physical activity, a family history of diabetes, lipid disorders, metabolic syndrome, cardiovascular disease (CVD), and increasing average age of the mother.

What are the risks to mother and baby?

Among the most serious complications is pre-eclampsia, which affects both the mother and the unborn baby. This condition occurs when the placental blood vessels are not dilated enough, resulting in a reduced supply of oxygen and blood to the foetus. It is manifested by high blood pressure and proteinuria. Another complication is increased amniotic fluid, the fluid that surrounds the baby in the uterus during pregnancy, or recurrent urinary infections. Mothers with GDM often have a large foetus with a high birth weight of over 4000g. This frequently necessitates operative management of labour, such as delivery by caesarean section, as spontaneous labour increases the risk of birth injuries.

The risk to the newborn depends on both the duration and the quality of management of GDM. Hypoglycaemia, polycythaemia, hyperbilirubinaemia, and mineral imbalances may be present in the first hours after birth. There are known conditions with a severe course of respiratory insufficiency syndrome. The newborn may be obese but despite excessive birth weight, the vital organs of the newborn may be functionally immature. In later development, children of mothers with GDM may have various neuropsychiatric disorders and, in adulthood, an increased risk of obesity, diabetes, and cardiovascular and cerebrovascular disease.

Can you describe the screening process for GDM and the role of the oral glucose tolerance test (oGTT)?

Diabetes Mellitusreening is carried out in the first and second trimesters. In the first trimester, fasting blood glucose is examined. If the fasting glucose level is ≥ 5.1 mmol/L on two separate days, the result is evaluated as GDM, and the patient should be referred to a diabetes clinic. In the second trimester, between the 24th and 28th weeks, the pregnant woman undergoes a standard oral glucose tolerance test (oGTT). The oGTT must be conducted in a standardised manner and under standard conditions, otherwise it loses its diagnostic value.

What conditions need to be met for an objective oGTT?

For the oGTT to be objective, it must be conducted under standardised conditions. The test is performed in the morning after at least eight hours of fasting, although plain water is allowed. Normal eating habits should be observed three days before the test, and increased physical exertion should be avoided. A load of 75 grams of glucose dissolved in 250 ml of clean water is administered, which must be consumed within two to three minutes. Blood samples are taken exclusively from a vein, first on an empty stomach and then one hour and two hours after drinking the glucose solution. During the test, the patient must remain calm, refraining from walking. Any medication that could affect insulin levels can only be taken after the test is completed.

How is GDM managed once diagnosed, and what are the implications for prenatal care?

Achieving optimal control of glucose metabolism both before and during pregnancy is crucial for minimising complications in pregnancy. If GDM is confirmed, the pregnant woman is under the care of a diabetes clinic, where further necessary investigations are performed, and care is modified every two weeks according to the results and type of treatment. Treatment is carried out in close cooperation with the gynecologist, who monitors fetal development by ultrasonography. Information on growth or stunting is an important criterion for managing GDM treatment to achieve optimal metabolic compensation. Patients also have a glucometer for self-monitoring of blood glucose at home, following the guidelines of the diabetologist. 

What are the long-term health problems for women who have had GDM?

Postpartum care for women with GDM includes monitoring the glycaemic profile after discontinuation of treatment. Postpartum oGTT should be performed no later than six months postpartum to rule out type 2 diabetes mellitus. 

Overall effective management as outlined in our discussion helps ensure a healthy pregnancy, and reduces the risk of long-term health problems for both mother and baby.