Gestational diabetes mellitus (GDM) is a diabetes that can occur during the second trimester of pregnancy (gestational) usually around the 24 – 28 weeks mark. The condition usually goes away after the birth of the baby. Here we answer all of your questions about GDM.
It’s a condition that affects between 12-14% of pregnant women. It’s not the same as having pre-existing diabetes, and typically women don’t have any symptoms. It is diagnosed when a woman has higher than normal blood glucose levels during pregnancy.
All women are screened for it at their routine 24-28 week check-up. However, women who are at higher risk may be tested more often. You are at higher risk if you:
The ‘glucose tolerance test’ is the diagnostic test used. You will be required to fast for 10 hours (which is generally overnight and you’ll skip breakfast). First, a blood test is taken. Then you will drink a glucose drink, followed by further blood tests one and two hours later. You’ll need to stay at the laboratory for the full two hours.
Most women with GDM will have a healthy pregnancy, normal delivery, and a healthy baby.
About 30% of women with GDM have larger than average babies. As a result, they are more likely to have interventions in labour, but the baby will not be born with diabetes.
Studies have suggested that women who develop GDM have a 50% increased chance of developing type 2 diabetes later in life, and that their baby is also at greater risk of developing type 2 diabetes in life.
Some women may need no treatment, while others need a strict diet, or insulin injections.
You may be referred to an obstetrician or dietitian, who will advise you further. A healthy low-fat, low-sugar diet and regular exercise can help reduce blood sugar levels. Read What Should Be Included in a Gestational Diabetes Diet?
If your baby is larger than normal, it will be recommended that you give birth in a hospital as it might lead to birth difficulties.
2-4 hours after the birth of your baby, they will receive a heel prick blood test to check whether their blood glucose is at a safe level. If it can’t be maintained at a safe level, they may be given a drip.
You will be able to stop all treatments after the birth, and will be offered a test to check your own blood glucose levels before you go home.