Pregnancy and High Blood Sugar (Gestational Diabetes)
What is gestational diabetes?
Gestational diabetes is a form of diabetes (abnormally high blood sugar) that occurs during pregnancy. It is usually diagnosed during the late stages of pregnancy commonly between the 6th and 7th month of pregnancy. If you are diagnosed with gestational diabetes early in pregnancy, you may have had it before you became pregnant.
What is the cause of gestational diabetes?
When you get pregnant, and your baby begins to grow, your baby’s placenta produces hormones that cause a build up of sugar in your blood. You need insulin to transfer this sugar from your blood into your muscles and liver. In a pregnant without diabetes, the pancreas produces more insulin in response to the elevated blood sugar. However, when you are diabetic, your pancreas is not able to meet the demand, and the sugar stays in your blood, causing elevated blood sugar (hyperglycaemia).1,2
What increases my chances of having gestational diabetes?2
- Being overweight
- Previously had gestational diabetes
- Being pre-diabetic (fasting blood sugar between 100-125mg/dL)
- Family history of type 2 diabetes
- Have had large babies
- Have had polycystic ovarian syndrome
How do I know if I have gestational diabetes?
The oral glucose tolerance test can be done which will check your body’s ability to respond to a glucose load. After fasting and taking only water for 8-12 hours, your blood sample is taken and tested. Then you take a drink containing 75g of glucose and blood sample are taken at 1-hour and 2-hour intervals and glucose levels are checked.2
How will gestational diabetes affect my baby?
- Your baby may be larger than normal, also called foetal macrosomia. This can make delivery difficult and more dangerous for your baby.
- The baby may be hypoglycaemic i.e. having dangerously low blood glucose levels.
- The baby may be born with breathing problems, occurs in a condition known as respiratory distress syndrome.
- The baby may die before or soon after birth.
- The baby may be born with jaundice, a condition where the skin and white of the eye turn yellow. Jaundice may go away but your baby may need to be placed under special lights and given plenty of breast milk to help.1
How is gestational diabetes treated?
1) Healthy eating– Following a healthy eating plan is very important in diabetes management as it will help to:
- Keep your blood glucose levels within the target range advised.
- Provide adequate nutrition for you and your baby.
- Achieve appropriate weight changes during pregnancy.
If you already have gestational diabetes, you are advised to:
- Eat regular meals
- Eat small amounts often
- always include some carbohydrates in every meal or snack.
These can be done by choosing foods that are good sources of carbohydrates, provide the nutrients you need during pregnancy and are low in fat, particularly saturated fats and high in fibre. Nutrients of high value in pregnancy include:
- Calcium, sources include milk, cheese, nuts.
- Iron, sources include read meat, chicken, fish.
- Folic acid, sources include dark green leafy vegetables2
It is generally recommended that the balance of food types in pregnancy in women with diabetes should be as follows:
- Carbohydrate – 40%
- Fat – 40%
- Protein – 20%
The carbohydrate should contain high levels of fibre as this will ensure a slow rise in levels of blood sugar after meals through a gradual absorption of glucose from the intestine.3
2) Physical activity- Physical activity can help you reach your blood glucose targets. It is never too late to start being more active and there are many ways that you can perform exercises as part of your daily routine. Walking is one of such ways. Here are a few tips on how to incorporate more walking into your life:
- Walk instead of driving to nearby places
- Taking stairs rather than lifts. When you are going up 1 or 2 flights
- Standing and moving while on the phone
- Parking a good distance from your destination so you can walk the remaining distance
For women with gestational diabetes, moderate intensity physical activity can help to manage blood glucose levels. Moderate exercise means a slight but noticeable increase in breathing and heart rate. You can get a pedometer from a local pharmacy or sport shop, to help you count your daily steps and you should aim for 10,000 steps per day.
It is very important that you avoid activities in which you can get hit in the stomach such as basketball, soccer.Do not exercise on your back after the first trimester, these kind of physical activity can put too much pressure on an important vein and limit the blood flow to your body.2
3) Insulin– Insulin is usually added when complying with a healthy diet and exercise plan is insufficient. Oral medications aren’t considered safe in pregnancy.1,2
The injected insulin will help to lower your blood glucose level to within a range that is best for your baby’s growth and development. It doesn’t cross the placenta or affect the baby.2
It is equally important to check your blood glucose levels when using insulin so as to easily detect any hypoglycaemia (low blood sugar) that may ensue. If this happens, having a drink or food containing quick acting glucose will work.
What is blood glucose target?1
Time of day
Before meals and when you wake up
What happens after birth?
The best way to give your baby a healthy start is by breast feeding. Breast feeding helps to maintain your baby’s glucose levels and can help to avoid low blood glucose levels for your baby.
For your body, you will have to check your blood glucose 6-12 weeks after delivery to see if you still have diabetes. For most women, blood glucose levels return to normal after pregnancy, however, this is not the case in 5-10% of women.1
Even if your blood glucose levels return to normal after pregnancy, your chances of having diabetes late in life is still high, usually 10-20 years after delivery. Therefore, you should test yourself at least every 3 years for diabetes or pre-diabetes.2
How can I prevent or delay diabetes later in life?
- Reach and stay at a healthy weight.
- By physically active for at least 30 minutes most days of the week.
- Follow a healthy eating plan.
- Ask your doctor if you can be placed on metformin tablets, an oral diabetic drug.
By delaying or preventing diabetes, you will also lower your chances of having heart and blood vessel disease and other problems as you get older.
If you plan on having another baby, your blood glucose needs to be at a healthy level before the new pregnancy.1
1) What I need to know about Gestational Diabetes. National Institute of Diabetes and Digestive and Kidney Diseases. NIH Publication No. 13-5129, August 2013
2) Gestational Diabetes – Caring for yourself and your baby. National Diabetes Service Schem. Version 1, July 2010
3) Veikko A. Koivosto. Meal-time blood sugar control in pregnancy. Diabetes Voice, Volume 49, December 2004