Gestational diabetes is diabetes first diagnosed during pregnancy. It usually disappears after birth, but needs careful monitoring because it can affect the health of both mother and baby.
This article is for information. During pregnancy, any change to diet, treatment or monitoring must be agreed with the doctor overseeing the pregnancy.
When is gestational diabetes testing done?
Testing is often done in the second trimester, but may be recommended earlier if there are risk factors: a history of gestational diabetes, obesity, prediabetes, polycystic ovary syndrome or a family history of type 2 diabetes.
The doctor may recommend fasting blood glucose, a glucose tolerance test or other tests depending on the context. If you already have results and do not understand them, test interpretation can help you formulate the right questions for your treating doctor.
Which levels are monitored?
Glucose targets in pregnancy are stricter than outside pregnancy and need to be individualised. Do not use other people's values as your reference. Measurement timing matters: fasting, before a meal, one hour or two hours after a meal. For differences between measurement times, also see the guide to fasting and postprandial glucose.
Nutrition in gestational diabetes
The aim is not a restrictive diet, but regular meals that avoid glucose spikes and provide enough nutrients for pregnancy. In practice, the following help:
- carbohydrates spread throughout the day rather than concentrated in one meal;
- protein at every meal: eggs, fish suitable in pregnancy, lean meat, dairy and pulses;
- fibre from vegetables, whole fruit and wholegrains;
- avoiding juice, high-sugar sweets and sugary liquid snacks;
- gentle exercise after meals if your obstetrician allows it.
A personalised nutrition plan is useful when pregnancy, glucose, nausea, working hours and actual food preferences all need to be accommodated.
After birth
Gestational diabetes increases the later risk of type 2 diabetes. Testing after birth and periodic monitoring are therefore important. Lifestyle, weight, breastfeeding, sleep and physical activity form part of the long-term prevention plan.
