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The NDSS is administered by Diabetes Australia
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Diabetes and pregnancy risks, for women with type 1 diabetes

Most women will have a healthy baby, but all pregnancies can have problems regardless of whether the mother has diabetes.

Having diabetes brings some additional risks, but looking after yourself and your diabetes can help to reduce these risks.

Risks to your baby in early pregnancy

Diabetes can increase the risk of birth defects (congenital abnormalities) in babies. These abnormalities are more common when diabetes management before and during early pregnancy has not been optimal. Damage to the baby’s heart, spine and kidneys can occur during the early stages of pregnancy, often before women realise they are pregnant.

Miscarriage can also occur, as it can for all women. The risk of miscarriage increases when HbA1c is above the target range before pregnancy and in the early stages of pregnancy.

To reduce your risk of miscarriage and of your baby developing abnormalities, it’s important to maintain the best diabetes management you can.

Risks to your baby during pregnancy

Glucose can cross the placenta to your baby, so your baby’s blood glucose levels will reflect your own. If your blood glucose levels are high, the normal response of your baby will be to produce extra insulin for themselves (this occurs from about 12 weeks gestation). The combination of extra glucose and extra insulin can make your baby grow too big. Having a large baby can cause problems during labour and birth. High glucose levels during pregnancy may also increase the risk of long-term health problems for your baby.

Risks to your newborn baby

Babies may have low blood glucose levels (hypoglycaemia) after birth. The higher your blood glucose, the higher the glucose supply will be to your baby before birth. The extra glucose stimulates the baby’s pancreas to make more insulin. After birth, your glucose supply to your baby suddenly stops, but your baby may continue to produce excess insulin for several hours and even up to one or two days after birth. This can cause hypoglycaemia in the baby. Hypoglycaemia is more likely to happen if babies are born early or if they are very small or large. Your baby could also have trouble with feeding, breathing or other medical problems.

Keeping your blood glucose levels as close to target as possible during pregnancy and birth will dramatically reduce the risk of these problems.

Reducing the risks

The aim is to have your HbA1c less than 6.5% (48mmol/mol), if possible, for three months before you become pregnant and in the early part of your pregnancy (first trimester). Your diabetes in pregnancy team will discuss your personal HbA1c goal with you before you conceive.

During pregnancy, your diabetes in pregnancy team will work with you to keep your blood glucose levels as close to your target range as possible. This will help to reduce the risk of your baby growing too big or having hypoglycaemia after birth.