Diabetes during pregnancy includes pre-existing diabetes (Type 1 or 2) and gestational diabetes, which is diagnosed for the first time in the pregnancy.
Pre-existing diabetes
This is when diabetes has already been diagnosed and is managed with improving diet and initiating medication, in the form of metformin and/or insulin. Keeping the blood sugar levels in a normal range throughout the pregnancy, can help prevent complications
Gestational diabetes (GDM)
This is a form of diabetes that is diagnosed in the pregnancy and can very often resolve once the pregnancy is over. This is diagnosed either by a high fasting blood sugar, or via doing a glucose tolerance test, which involves drinking a glucose solution and testing the blood after one and two hours.
A glucose tolerance is done if there are risk factors for GDM, these include:
- Previous gestational diabetes
- Previous baby delivered over 4 000g
- First degree relative with diabetes
- Advanced maternal age
- Increased BMI
- Repeated sugar found in the urine on dipstick
Management of diabetes in pregnancy
It is vital to keep blood sugar levels stable during the pregnancy. A raised blood sugar will have effects on the fetus depending on the stage of development.
In the first trimester, a persistently high blood sugar can cause birth defects of the fetal heart and spine, while later in the pregnancy this can cause excessive fetal weight gain, resulting in an abnormally large baby.
Blood sugar levels can be kept low through dietary changes that involve consuming less sugar and certain carbohydrates. If this is not sufficient in keeping levels low, a medication like metformin can be initiated and later insulin, if necessary. Often as the pregnancy progresses, the treatment will escalate as well.
Things to avoid in a pregnancy with diabetes
- Added sugar: sugar in coffee/tea, sweets, and chocolates
- Processed/refined carbohydrates: white bread, maize meal, takeaway foods
- Consuming large amounts of fruit with high sugar load: bananas, grapes, pineapple, dried fruit
- Carbohydrate based drinks: sports drinks, energy drinks, fruit juices
Recommended diet and exercise
- Regular exercise: at least 30 minutes of low impact exercise three times a week
- Eating lean protein, healthy fats
- Increasing amounts of vegetables and low sugar containing fruits
- Whole grains and low glycaemic index foods
- Drinking 2 litres of water a day
Blood sugar levels need to be tested multiple times a day and more frequent visits with a specialist are required. The baby’s growth and development are monitored closely by frequent ultrasound scans. It is recommended that delivery of the baby occurs at 38 weeks, via a planned induction (if the baby is a normal size) or via caesarean section.
After delivery it is important to test the baby’s sugar level and to ensure feeding every 2-3 hours. In the event of gestational diabetes, after delivery the mother’s sugar levels are monitored to assess if treatment needs to continue, and a sugar test is repeated after 6 weeks postpartum.
Increased risks in diabetes
- Birth defects (if sugar is uncontrolled in the first trimester)
- Development of pre-eclampsia (high blood pressure occurring in pregnancy)
- Birth injuries if the baby is macrosomic (large for gestational age)
- Developing Type 2 diabetes later in life
Having diabetes in pregnancy, constitutes a high-risk pregnancy and requires specialist care.
