Gestational Diabetes

(Also called glucose intolerance of pregnancy)
This is a complication of pregnancy and usually appears in the later half (5-6th month), when the baby is fully formed but still growing. It affects around 3-7% of women, who will never have had any signs of diabetes before.

So why does a pregnant woman suddenly develop this?

For some reason, which would appear to be genetic, these woman have a pancreas that works 'on the edge' so to speak. It is quite capable of doing its job very efficiently under normal circumstances but when called on to go beyond that it cannot cope.

Though not thoroughly understood it is thought that hormones produced in the placenta, which are needed for the development of the baby, also block the action of insulin in the mother's body, thus producing insulin resistance. This means she needs more insulin than normal to counteract that resistance and when she can no longer produce enough insulin she develops gestational diabetes.

Insulin is needed by the body to remove sugars, in the form of glucose, from the blood and pass it into the cells where it can be used as energy. When there is too little insulin the glucose builds up in the blood to high levels.

What are the effects on mother and baby?

This is the first thing all mothers-to-be want to know! Do not panic. Untreated, I repeat, untreated gestational diabetes will have risks but treated mums should have successful pregnancies and healthy babies.

Effect on baby

The bigger the baby the greater the risk of injury during normal delivery, e.g. shoulder damage (known as shoulder dystocia) during birth.

Also, due to the extra insulin made by the baby's pancreas in response to the mother's high blood glucose, new-born babies may have very low blood glucose levels. This is because, for a short while after the birth the baby may continue to make this extra insulin although the high glucose levels are no longer there.

Some babies are born with Respiratory distress syndrome ( breathing problems due to under-developed lungs). This usually goes away with time.

The baby may develop jaundice, which means it's skin and eye whites will appear yellow. This is not a serious complication and will fade in time, usually without treatment.

The baby may have low blood calcium. Calcium is important in the development and maintenance of the bones and in tooth formation.

There is the increased risk that the baby may be born with congenital problems like heart defects.

There is also a slightly greater chance of the baby being stillborn or dying as a new-born, but in treated gestational diabetes this is very rare.

These babies also have the greater risk of weight problems during childhood and of developing type 2 diabetes as adults.

Effect on mother
If you keep your blood glucose levels within the safe range then there should be no health risks or complications - however.....

Because of the size of the baby it may mean a caesarean section will be necessary.
In some women it can result in high blood pressure.
Occasionally preeclampsia and urinary tract infections are a problem.
A woman who gets gestational diabetes once is more likely to develop it in future pregnancies.
Women who get gestational diabetes are at a higher risk of developing type II diabetes later in life, when some other factor such as stress or weight increase tips their pancreas 'over the edge' again.

So what are the chances of one getting gestational diabetes?

There are certain factors that put you in the high risk category.
These are :-

1. You are overweight - BMI (body mass index) greater than 27.
2. You have family members with type 2 diabetes.
3. Someone in your family has had gestational diabetes.
4. You have had gestational diabetes in a previous pregnancy.
5. You are older than 25. Older women are at greater risk of getting diabetes.
6. You have had a very large baby in a previous pregnancy - greater than 9 pounds.
7. You have had a stillbirth in late pregnancy or spontaneous miscarriage.
8. You have had a baby born with an abnormality.
9. You are a member of an ethnic group that is considered at high-risk e.g. African American, Native American, Hispanic, Pacific Islander, South or East Asian or indigenous Australian.

If two or more of the above apply to you then you are at high risk and should be tested as soon as you know you are pregnant and again at 24-28 weeks.

Answering yes to only 1 of them you puts you in the average risk range and you should still get tested at 24-28 weeks.

Paying attention to your risk factors is important because gestational diabetes can be present with no obvious symptoms.

The symptoms of increased thirst, urination, hunger and high blood pressure are ones that are common in later pregnancy anyway so the diabetes may be overlooked.

The routine urine test done by your health care professionals should pick up any high glucose levels but unfortunately high sugars in urine is common in pregnancy caused by glomerular filtration, so confirmation of gestational diabetes is with a glucose tolerance test.

If you are pregnant and have been diagnosed with gestational diabetes do not feel you have been handed down a life sentence.

Unlike other types of diabetes, which are permanent, this one is controlled with the correct treatment and goes away after the birth of the baby. Don't panic if it does not disappear immediately you leave the delivery room - sometimes it can take several weeks. Your doctor will usually order tests to check about 6 weeks after the birth.

However as both gestational diabetes and type 2 diabetes involve insulin resistance there does appear to be some sort of link between them, this idea being fostered by the fact that many women who have gestational diabetes go on to develop type 2 diabetes later on in life.

It is, therefore, a wake up call to start leading a more healthy lifestyle which in itself may mean you never go to the further step of getting Type 2.

A rare 5-10% of women with gestational diabetes develop Type 1 diabetes sometime in their life.

It is thought that these women have LADA (latent autoimmune diabetes in adults) which is a slowly developing form of Type 1 that is brought to light during pregnancy.


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