Gestational Diabetes

What is Gestational Diabetes?

Gestational diabetes is caused by the hormones produced during pregnancy which make it difficult for the body to use insulin properly. As a result, there is an increase in insulin resistance. Pregnancy places a significant demand on the body and as a result, some women are less able to produce enough insulin to overcome insulin resistance. It becomes difficult for the body to use glucose properly for energy, thus the glucose remains in the blood and levels rise, resulting in gestational diabetes.

Pregnant women in their second or third trimester are usually affected. What is important about gestational diabetes is that women don’t usually have diabetes beforehand and the condition goes away after giving birth. Women can also be diagnosed during their first trimester, however in these cases, diabetes most likely already existed before the pregnancy.

Risk Factors

Much like type 2 diabetes, gestational diabetes also has an increased probability to increase a woman’s risk of developing the condition:

  • Being overweight or obese.
  • Had gestational diabetes before.
  • Previously giving birth to a very large baby, of around 10Ib/4.5kg or over.
  • Your parents or siblings having diabetes.
  • You are of South Asian, Black or African Caribbean or Middle Eastern decent.


Gestational diabetes doesn’t usually cause symptoms. Most cases are usually detected when your blood glucose level is routinely tested for gestational diabetes.

Symptoms can present themselves when a woman’s blood glucose levels become too high:

  • Increased thirst
  • Increased need to urinate
  • A dry mouth
  • Fatigue

Some of these symptoms are quite common during pregnancy and aren’t necessarily an urgent problem. However, if you have concerns, always consult your doctor or midwife.


Gestational diabetes can lead to the follow problems:

  • The baby’s head could grow larger than usual. This may lead to difficulties during delivery and increases the likelihood of needing an induced labour or caesarean section.
  • Too much amniotic fluid could develop (polyhydramnios). This is the fluid that surrounds the baby and too much could cause premature labour or issues during delivery.
  • Premature birth (before the 37th week of pregnancy).
  • Pre-eclampsia, which is when high blood pressure occurs during pregnancy, when the mother’s blood pressure was previously normal. If left untreated, there can be complications which can include damage to the internal organs (most often the liver and kidneys).
  • The baby could develop low blood glucose levels or yellowing of the skin and eyes (jaundice) after they are born. This may require hospital treatment.
  • In rare cases, the loss of the baby can occur (still birth).

Most women who have gestational diabetes have otherwise normal pregnancies and give birth to healthy babies. You will be effectively monitored for such issues throughout your pregnancy and birth.

Screening for Gestational Diabetes

During your first antenatal appointment at around 8 to 12 weeks of your pregnancy, your midwife or doctor will ask you some questions to assess whether you’re at risk of developing gestational diabetes. If you are at risk, you will go through a screening test known as an oral glucose tolerance test (OGTT).

The screen process involves an initial blood test, that is taken in the morning when you’ve fasted overnight. You’re then given a glucose drink. After resting for two hours, another blood test is taken to see how your body is dealing with the glucose.

An OGTT is completed when you’re between 24 and 28 weeks pregnant. Screening will be completed much earlier in the pregnancy if you have already experienced gestational diabetes before. Then you’ll have another OGTT at 24 and 28 weeks if the first test was normal. If you’ve had a previous episode of gestational diabetes, it might be suggested that you start testing your own blood glucose levels.


The main purpose of any treatment or precaution is to reduce the risk of complications related to gestational diabetes:

  • Controlling blood glucose levels by using a blood testing kit.
  • Changes in diet and exercise.
  • A majority of women will need medication in the form of tablets or insulin injection. Medication is usually introduced if blood glucose can’t be reduced through other methods.
  • Close monitoring of the entire duration of the pregnancy and birth is necessary to monitor any problems.
  • It is best for a woman with gestational diabetes to give birth before 41 weeks. An early delivery may be recommended if there are concerns about you or your baby’s health. It may also be recommended if your blood glucose levels haven’t been well managed. An induction or caesarean section may be recommended if labour doesn’t occur naturally.

 Long-Term Effects

There can be potential long-term effects because of gestational diabetes. You will also need to take further precautions following birth:

  • Women who have had gestational diabetes are more likely to develop it again during another pregnancy.
  • Women who have had gestational diabetes are more likely to develop type 2 diabetes.
  • You will need a blood test to check for diabetes 6 – 13 weeks after giving birth and every year thereafter if the result is normal.
  • If you develop any symptoms, consult with your GP even if you are feeling well.
  • You will be advised on reducing the risk of diabetes through maintaining a healthy weight, eating a balanced diet and exercising regularly.
  • Some research has suggested that babies of mothers with gestational diabetes may be more likely to develop diabetes or become obese later in life.