What causes gestational diabetes?
Hormone changes due to pregnancy can affect the way a woman's body responds to insulin, the hormone that helps move glucose from the blood into cells where it can be used for energy.
During pregnancy the placenta - the organ that feeds and delivers oxygen to your baby - releases hormones that help your baby grow. Some of these hormones, including oestrogen, progesterone and human placental lactogen (HPL), make it harder for your body to make or use insulin. This is called insulin resistance.
If pregnancy makes you more insulin-resistant, this may be diagnosed as a specific type of diabetes associated only with pregnancy, called gestational diabetes.
With gestational diabetes, blood sugar (glucose) levels can become high, with the potential of causing health problems for the mum and her growing baby.
Once detected through routine antenatal screening, gestational diabetes can usually be treated and managed for a healthy pregnancy. The diabetes usually goes away after the baby is born.
The risk of developing gestational diabetes is higher for women who:
- Were overweight before becoming pregnant, as carrying extra weight makes it harder for the body to use insulin
- Had a previous child weighing 4.5kg (10lbs) or more at birth
- Had gestational diabetes in a previous pregnancy
- Have a close family history of diabetes
- Are from certain ethnic backgrounds, including South Asian, black Caribbean or Middle Eastern