Dr.ª Andreia Cruz
Internal Medicine 
Diabetes and Gestational Diabetes Consultation 

Gestational diabetes

HPA Magazine 15

Gestational Diabetes (GD) is defined as a type of intolerance to carbohydrates (sugars) diagnosed or detected for the first-time during pregnancy. It is an increasingly common diagnosis, especially in the last decade. It is the diagnosis that no pregnant woman likes to receive, especially when it happens in the first trimester. Social structure and lifestyle have undergone changes that are reflected in women’s characteristics; becoming pregnant later on in life and being overweight.

The most recent data available is for 2018, where the prevalence of GD was 8.8% of pregnancies registered in the NHS, 9.9% in age group 30-39 years and 17.7% in women over the age of 40 years.
At HPA in Gambelas we have a Gestational Diabetes Consultation in cooperation with the Obstetrics team, with follow-up protocols during pregnancy, childbirth and postpartum reassessment. The great challenge of the GD consultation is to destroy myths, associated with diagnosis and diet, and to motivate the pregnant woman to follow a diet until the delivery date and when necessary to begin therapy.
In the first consultation with the Obstetrician, all pregnant women should be submitted to a fasting blood glucose analysis test, after 8 to 12 hour fasting period. When the result is above or equal to 92 mg / dl, a diagnosis of gestational diabetes is confirmed. Those whose values are under 92 mg / dl, are subsequently subjected to an oral glucose tolerance test, between 24-28 weeks, meeting the diagnostic criteria for the existence of one or more altered values.
From the initial diagnosis, the pregnant woman will undergo blood glycemia analysis and ketones analysis of the first morning urine. She will be given dietary recommendations and referred for a consultation with the Nutritionist. Exercise will also be advised, namely walking, preferably after a meal, when there is no obstetric contraindication. Daily and methodical assessment of blood glucose level is the only way to understand whether pharmacological intervention is necessary.
 

The polyfactionated diet (3 main meals, 2-3 snacks per day and supper) and exercise are the two pillars of the treatment. Only when these together do not reach the metabolic objectives do we resort to pharmacological therapy.
Pharmacological treatment options are oral antidiabetics (metformin and glibenclamide) and insulin. Both are safe and there are no differences regarding the evolution of pregnancy and neonatal complications. However, oral antidiabetics are less expensive, easier to administer and preferred by pregnant woman (since insulin has to be injected).
The goal of GD treatment is one of the goals set out in the Declaration of S. Vincent in 1989 “for the result of pregnancy in women with diabetes to be as close to the result of pregnancy in women without diabetes”. With a good metabolic control associated with adequate obstetric surveillance, we have managed to significantly reduce the risk of foetal and maternal complications.
After delivery, 6 to 8 weeks later, an oral glucose tolerance test must be done. These women have a significant risk of GD in future pregnancies (60-70%) and an increased risk of diabetes in the future (25 to 75%).
Thus, before a next pregnancy it is advisable to stabilize or reduce weight and assess the metabolic situation (fasting blood glucose and / or HbA1c analysis).
An annual assessment of the metabolic situation is also suggested and maintaining healthy lifestyle habits: once again a polyfractionated diet and exercise.