Gestational diabetes

Gestational diabetes
What are the risks of gestational diabetes? Find out how to prevent and control it.

Women can develop diabetes during pregnancy. What are the risks for the baby and the mother? Can it be prevented?

What is gestational diabetes?

Diabetes during pregnancy is called gestational diabetes. Due to hormonal changes during pregnancy, some mothers-to-be develop high blood sugar levels. An organ called the placenta, which connects the fetus to the uterus, produces hormones that interfere with the effects of insulin (a hormone that controls blood sugar levels).

Cases of gestational diabetes have been on the rise in recent years.

Gestational diabetes affects 7 to 9 percent of pregnant women in Quebec. It most often appears in the second trimester of pregnancy and usually goes away after childbirth.


In general, gestational diabetes does not cause obvious symptoms. Furthermore, it often goes unnoticed because the symptoms resemble the normal effects of pregnancy. Some women may experience the following:

  • Dizziness or increased fatigue
  • Increased thirst
  • More frequent need to urinate and in greater amounts
  • Headaches
  • Dry mouth

If you experience any of these symptoms, it’s recommended to consult a doctor as soon as possible.

Risks to the baby at birth

  • Higher-than-average weight (more than 4 kg, or 9 lb.)
  • Injury to the arms when the baby’s shoulders emerge (due to higher weight)
  • Hypoglycemia (low blood sugar)
  • Jaundice
  • Lack of calcium in the blood
  • Difficulty breathing

Bear in mind that gestational diabetes does not increase the risk of birth defects or the risk of your child being born with diabetes. However, it does increase their risk of obesity and glucose intolerance in early adulthood.

Risks to the mother

Gestational diabetes may cause the following:

What are the risk factors?

  • You are over 35 years old
  • You are obese (BMI over 30)
  • You gain more than 15 kg (35 lb.) during pregnancy, regardless of pre-pregnancy weight
  • You have a history of diabetes during pregnancy
  • You have previously given birth to a baby weighing more than 4 kg (9 lb.)
  • Your father, mother, brother, or sister has diabetes
  • You take a cortisone medication on a regular basis
  • You have polycystic ovary syndrome
  • You have acanthosis nigricans, a type of skin discoloration
  • You have a history of abnormally high blood sugar levels

Women of Indigenous, Latin American, Asian, Arab, or African descent are also at higher risk of developing gestational diabetes.

Screening test

All women should be tested for gestational diabetes between weeks 24 and 28 of pregnancy. However, if you are at higher risk, you will need to be screened earlier, around week 12.

There are two types of screening tests. Your prenatal care provider will tell you which one you’ll need to take. One of the tests is done on an empty stomach, while the other is not. Both involve drinking a sugary solution followed by having a blood test done to see how your body reacts to the sugar.

How can gestational diabetes be prevented?

Maintaining a healthy weight lowers your risk of developing gestational diabetes.

You can also prevent gestational diabetes by eating a varied and balanced diet and being physically active. For example, walking is a good way to begin exercising more often.

What should you do if you have gestational diabetes?

Your doctor may refer you to a nutritionist to make changes to your diet, such as cutting down on sugar and eating more nutritious, healthy foods. You should also try to do more physical activity.

If you follow these tips carefully, your blood sugar level should go down. There’s no need to eliminate carbohydrates from your diet completely, but you should aim to distribute them throughout the day. Often, gestational diabetes can be managed with healthy eating and exercise. If this does not work, however, insulin treatment may be necessary.

Precautions: Know the signs of hypoglycemia

If you’re experiencing extreme fatigue and symptoms such as abnormal sweating, headaches, dizziness, weakness, and tremors, you may have hypoglycemia.

Hypoglycemia occurs when your blood sugar level is lower than normal. Potential causes include the following:

  • Taking too much medication (insulin) relative to the amount of food you’ve eaten
  • Exercising excessively
  • Consuming alcohol
  • Skipping meals


Things to keep in mind

  • Having a healthy weight before pregnancy reduces the risk of developing gestational diabetes.
  • It’s often possible to control gestational diabetes by changing your diet and exercising.
  • When gestational diabetes is not controlled, it poses risks for both mother and baby.


Naître et grandir

Scientific review: Dr. Jean-Philippe Blais, physician at the Clinique de Périnatalité de Trois-Rivières
Research and copywriting: The Naître et grandir team
September 2018





Please note that hyperlinks to other websites are not updated regularly, and some may have changed since publication. If a link is no longer valid, use search engines to find the relevant information.

  • Diabetes Québec. “Diabetes in pregnancy.”
  • Doré, Nicole, and Danielle Le Hénaff. From Tiny Tot to Toddler: A practical guide for parents from pregnancy to age two. Quebec City, Institut national de santé publique du Québec.