Your expert guide to diabetes during pregnancy

Diabetes is a chronic condition that occurs either when the pancreas doesn’t produce enough insulin or when the pancreas produces insulin that the body can’t use. Having diabetes can increase the risk of serious health complications during the course of your pregnancy, and even before becoming pregnant. Keeping good control of your diabetes, however, can help to reduce this risk.

Here, Ms Vinita Singh, renowned consultant obstetrician, provides an expert insight into diabetes during pregnancy, including how to control your blood sugar level effectively.

Is diabetes a high-risk factor during pregnancy?

In short, yes. Diabetes - both pre-existing (Type 1 or Type 2) diabetes and diabetes that develops during pregnancy (called gestational diabetes) - can affect the course of pregnancy and cause harm to both you and your baby. In the same way, pregnancy can also worsen pre-existing diabetes.

Diabetes during pregnancy requires close and careful monitoring by a multidisciplinary team of diabetologists, obstetricians and midwives.

How should I prepare for pregnancy?

Ideally, a pregnancy should be planned. This is because the risks of diabetes can be minimised if the condition is well-managed before pregnancy. Women who have diabetes should consult their diabetologist and their GP for advice, and visit a diabetic pre-conception clinic as well, before trying for a baby.

The HBA1C test is a blood test used to measure the level of glucose in the blood. Ideally, this should be less than 48 (6.5%). Women with a blood glucose level above 86 (10%) are advised to not try for a baby until their diabetes is better controlled.

Women with Type 1 diabetes should have an eye exam before pregnancy, in addition to blood and urine tests for kidney function, to detect possible diabetes complications. This is important, because any pre-existing diabetes complications are likely to worsen during pregnancy.

In addition, women who have diabetes who are planning to become pregnant should also take 5mg folic acid (B vitamin) supplements daily until week 12 of their pregnancy. This is done to prevent the development of birth defects, such as spina bifida (a gap in the spine). A specialist will need to prescribe the folic acid.

Above all, women who have diabetes should continue using methods of contraception until their blood glucose level is under control.

Can pregnancy cause diabetes?

Anyone can develop gestational diabetes, but your risk increases if:

• You are over 40
• You are of Black, African-Caribbean, Middle Eastern or south Asian ethnicity
• You have a BMI (body mass index) above 30
• You had a baby who weighed 4.5kg or more at birth
• You developed gestational diabetes in a previous pregnancy
• You have a parent or sibling who has diabetes
• You had weight loss surgery, such as gastric bypass surgery

Women at risk for gestational diabetes will be offered screening for the condition during their pregnancy.

What are the symptoms of gestational diabetes?

In general, gestational diabetes doesn’t cause any signs or symptoms. Most women who have gestational diabetes are only diagnosed when their blood glucose level is tested during screening for the condition.

Women whose blood glucose level becomes too high (called hyperglycaemia) may develop symptoms, including:

• Increased thirst
• Frequent urination
• A dry mouth
• Tiredness
• Blurred vision
• Genital itching or thrush

However, these symptoms don’t necessarily indicate gestational diabetes, because they are also common pregnancy symptoms.

How can diabetes affect the health of my baby during pregnancy?

The effect of diabetes on your baby’s health will depend on your type of diabetes (pre-existing or gestational) and on the management of your diabetes.

Gestational diabetes can increase the risk of:

• Macrosomia, or a baby that is bigger than usual. Macrosomia can cause complications during delivery and increases the risk of needing induced labour or a caesarean section.
• Polyhydramnios, or too much amniotic fluid in the uterus. Polyhydramnios can lead to premature labour and complications during delivery.
• Pre-eclampsia, or high blood pressure (hypertension) during pregnancy. If untreated, pre-eclampsia can cause severe pregnancy complications.
• Premature birth of the baby before week 37 of pregnancy.
• Shoulder dystocia, which is when one or both of the baby’s shoulders get caught above the mother’s pubic bone during a vaginal delivery.
• Your baby’s admission to the neonatal intensive care unit for jaundice, respiratory problems, or a low blood sugar level (called hypoglycaemia).
• Stillbirth, although this is rare.

Type 1 and Type 2 diabetes, in addition to the risks associated with gestational diabetes, can increase the risk of:

• Miscarriage
• Birth defects, especially heart and nervous system abnormalities.
• Health problems after birth, such as heart and breathing difficulties, and needing medical care.
• Obesity that develops later in life.

Good diabetes management, before and during pregnancy, can help to reduce these risks.

How can I lower my blood sugar level during pregnancy?

Controlling blood sugar levels during pregnancy requires a stepwise control.

1. Diet ​

It is important to eat a healthy, balanced diet during pregnancy that meets your and your baby’s nutritional needs. This should include a wide variety of food groups, including fruits, vegetables, whole grains, legumes and healthy fats, that are eaten in the right amounts. For both your own and your baby’s safety, you shouldn’t cut out any food group from your diet.

Other things that you should also do include:

• Eating smaller, frequent, complex carbohydrate-containing snacks like soup, crackers or plain biscuits.
• Regularly sipping small amounts of water, instead of drinking large amounts in one go.
• Drinking a sugary drink if you don’t feel like eating. This can help to prevent hypoglycaemia if you take insulin for your diabetes.
• Not drinking any alcohol while you are pregnant. Drinking alcohol during pregnancy can cause harm your baby, increasing the risk of birth defects, fetal alcohol spectrum disorders, and a premature birth. If you take insulin for your diabetes, alcohol can also increase your risk for hypoglycaemia.

Vomiting can affect blood glucose levels. If you are repeatedly sick and/or have high ketone levels in your blood, seek medical help right away. Elevated ketone levels can lead to a serious diabetes complication called diabetic ketoacidosis, which is life-threatening for both you and your baby.

2. Exercise

Physical activity, such as walking, swimming or even pregnancy yoga, can help to lower your blood glucose level. There is a lot of support available to help you get active during your pregnancy, but if you are in doubt, ask your medical team for information about activities that you can participate in.

If you are at risk for hypoglycaemia (as a result of taking insulin for your diabetes), monitor your blood glucose level regularly and have a hypoglycaemia treatment close at hand when you exercise.

3. Medications

Some prescription oral medications are safe to take during pregnancy. If your blood glucose level is still not stable after changing your diet, exercising regularly and taking oral medications, then you may be given insulin injections.

If you had pre-existing (Type 1 or Type 2) diabetes, you will go back to your pre-pregnancy medication and dose.

If you developed gestational diabetes during the course of your pregnancy, all medications will stop after your baby is born. However, you will need to be tested for diabetes six weeks after giving birth and every year after that.

Ms Vinita Singh is a highly esteemed consultant obstetrician with over 25 years’ experience who specialises in all aspects of pregnancy and antenatal care and birth.

If you have diabetes and have any queries about your (future) pregnancy, don’t hesitate to book an appointment with Ms Singh via her Top Doctors profile today to receive expert advice and assessment.