Understanding Gestational Diabetes: What Expecting Mums Need to Know

Diabetes is a condition where your body is unable to regulate the amount of glucose in your blood, resulting in too much glucose (sugar) in your blood. Ordinarily, your blood glucose levels are regulated by insulin, a hormone that’s made in the pancreas, but occasionally the increase of particular hormones during pregnancy can stop insulin from working properly, resulting in a temporary form of diabetes called gestational diabetes. Gestational diabetes effects 3 -10% of pregnant people and those that develop this during pregnancy will have an increased risk of developing type 2 diabetes mellitus after pregnancy. Additionally, their children are at a higher risk of developing childhood obesity and type 2 diabetes later in life.

Many people will have higher than normal levels of blood sugar/glucose from time to time during pregnancy because pregnancy hormones suppress the release of insulin (the hormone that regulates blood sugar levels), so that a pregnant person's blood sugar levels are hopefully consistently higher than the average adult’s. (Your baby needs a steady supply of glucose to meet her/his growth needs.) It is important that during pregnancy you eat regular small meals that provide for sustained glucose release, rather than sugary snacks that cause short-term spikes in blood sugar levels.

Symptoms of gestational diabetes:

Gestational diabetes is usually discovered as a result of a routine blood sugar test that is performed on all pregnant people around 24 -26 weeks gestation, but if you are experiencing the following symptoms, you should discuss your concerns with your LMC:

• Excessive hunger and thirst

• Excessive urination

• Extreme tiredness

• Blurry vision

• High blood pressure

• Recurrent thrush infections

Some women are at higher risk of developing this condition.

The risk factors include:

• Over 30 years of age

• From a family with a history of type 2 diabetes

• Overweight or obese

• Ethnicity - some women from certain ethnic backgrounds are at higher risk

• Have a previous history of gestational diabetes

• Poor obstetric history – unexplained stillbirth, miscarriage

• Previous large baby or babies

• Polycystic ovarian syndrome

• A diet that consistently includes foods that have a high sugar content and are highly refined or processed and that lacks at least 5 servings of fresh vegetables and fruit daily

• Rapid, excessive weight gain in pregnancy

Gestational diabetes can also occur in women who have none of these risk factors.

Testing:

Polycose Testing or Glucose Screening in Pregnancy

This test is carried out in a medical laboratory or hospital. You will be asked to drink a liquid containing 50 mg of polycose (a type of sugar). One hour later a sample of blood is taken to see how well your body has metabolized this sugar. If your result shows that your blood glucose level is higher than 7.8mol/ml, you will be asked to take a Glucose Tolerance Test (GTT). This one-hour polycose screening test has a high false positive rate. Approximately 15 – 20% of pregnant women test positive on the polycose test although only 2 – 5% will have any form of diabetes. If you are at at risk of having GDM, your LMC may recommend missing out the Polycose test and taking a GTT so you get an accurate result and only have to have one sugary drink.

Treatment of gestational diabetes:

Gestational diabetes is usually successfully controlled by managing your diet and moderate exercise. After diagnosis you will need to will be put in touch with a nutritionist regarding your food consumption and encouraged to do regular physical activity. You will need to monitor your blood sugar levels several times a day via a blood test (finger prick test). You may be required to use insulin injections for the remainder of your pregnancy if you are unable to control your gestational diabetes through diet alone.

You may be wondering what are the possible complications associated with gestational diabetes?

During your pregnancy:

• Untreated, the high sugar (and fat) in the blood of a person with gestational diabetes can overfeed the baby while it is in your uterus, leading to "macrosomia" (a large baby).

• Premature birth (baby being born before 37 weeks) is more common.

• Miscarriage (before 23 weeks) and stillbirth rates (baby dying before birth) are also higher.

Delivery:

• Large babies often lead to higher rates of difficult births, a need for surgical (caesarean section) or an assisted delivery.

• Shoulder dystocia is a serious complication when the baby’s head passes through the vagina, but their shoulder gets stuck behind the mother's pelvic bone. When this happens, both mum and baby are more at risk of serious injury.

After birth:

• Babies can suffer from low blood sugar within the first day or two and need closer monitoring.

• Breathing problems are also more common shortly after birth.

Life long effects:

• Babies are at increased risk of developing diabetes or obesity (having a body mass index of more than 30) later in life.

• Women who have had gestational diabetes are also at much higher risk of developing diabetes in the future

Follow-up after your baby is born:

If you are diagnosed with gestational diabetes you will be offered a blood test during the first 24 hours after you’ve given birth and another 6 weeks after you’ve given birth to check that your blood sugar levels have returned to normal.

Up to 50% of women who are diagnosed with GDM will develop non-insulin-dependent diabetes at some stage in their lives. If you have been diagnosed with GDM you are advised to continue to follow the advice you were given about diet and exercise during pregnancy and to have your blood glucose levels tested each year.