Gestational diabetes is the most frequent complication in pregnancy. Gestational diabetes is carbohydrate intolerance causing hyperglycaemia (high blood sugar) that starts during pregnancy. Of the 700,000+ women who give birth in England and Wales each year, 30,600 developed diabetes during pregnancy (i.e. 4.3% of all pregnancies) and only 4,400 of them had diabetes before they became pregnant (i.e. 0.6%). Therefore, most pregnant women with diabetes did not have diabetes before they became pregnant.
Why is diabetes in pregnancy important? Gestational diabetes creates problems for women and their babies. It increases the risk of having a big baby with a birth weight over 4.5 kg (macrosomia) that may make labour difficult; increasing the risk of injury to the baby and mother during birth. It can lead to miscarriage, stillbirth or preterm birth. Uncontrolled diabetes can cause too much water (i.e. amniotic fluid) developing around the baby (i.e. polyhydramnios), congenital malformation, learning difficulties. Once the baby is born, he or she may develop neonatal hypoglycaemia (i.e. very low blood sugar in newborn babies). Furthermore, women with gestational diabetes are at higher risk of hypertension and pre-eclampsia during pregnancy, and diabetes after pregnancy.
We do not know what causes gestational diabetes, but we do know that women with the following factors are at a higher risk for developing diabetes during pregnancy: –
- Body Mass Index over 30 kg/m2; i.e. dress size 14-16 or over
- Physical inactivity
- Women aged 35 years or older
- Diet low in fibre, and an excess of high glycaemic index foods
- Parent or sibling with diabetes
- Excessive weight gain during pregnancy, especially women with a pre-pregnancy BMI over 30 kg/m2
- Previous baby with a birth weight 4.5 kg or over
- Gestational diabetes in a previous pregnancy
- Polycystic ovarian syndrome
- Women from ethnic groups that have a higher risk of diabetes
There are no guarantees when it comes to preventing gestational diabetes, but a consultation with a Registred Dietitian may make it less likely that you will develop diabetes during your pregnancy by helping to support you to make the following healthy changes:-
- Try to have and maintain a healthy weight before trying to have a baby
- Increase intake to 2 fruit and 3 or more vegetable portions a day
- Switch to high fibre and low glycaemic index foods
- Try to reduce your intake of saturated and trans fats
- Try to keep active during pregnancy
- Try to avoid gaining more than the recommended weight during your pregnancy
- Take folic acid and vitamin D3 supplements before and throughout your pregnancy
Finally, by having your first antenatal health check-up by 10-12 weeks of pregnancy you will be less likely to develop complications, including gestational diabetes. Early contact with your midwife or obstetrician ensures that you will receive timely advice and support to reduce the risk of having gestational diabetes, or start treatment early should you develop diabetes.