In some situations it isn’t clear why a certain woman has developed gestational diabetes, however you are more likely to have it if you:1,2
Gestational Diabetes doesn’t usually cause you to have any symptoms, and is usually just picked up on a blood test (see below). If it does cause any symptoms the ones to watch out for are:
Remember that some of these symptoms are common for all pregnancies anyway, but if you’re worried, speak to your midwife.
Should I be tested for Gestational Diabetes?
Not everyone is routinely tested for gestational diabetes. The National Institute of Clinical Excellence (NICE) recommends that women with any of the following risk factors are tested:1
Your midwife will book you in for this test if you meet the criteria at your booking visit. If you have had gestational diabetes before this test is done sooner.
Gestational Diabetes is usually tested for using the Oral Glucose Tolerance Test (OGTT)between 24 and 28 weeks. It is basically testing your body’s ability to process sugar and maintain a normal blood sugar level. There is no riskto you or your baby when undertaking this test. Instead, some hospitals will test you at your booking appointment with a fasting sugar blood test if you are high risk, and then again at 24 weeks.
Leading up to the test continue to eat your normal diet until the night before. From 10pm the night before you should only have plain water; this means no food including mints, chewing gum, and medication for heart burn (as this can effect the outcome).
When you come for your appointment you will have a blood sample taken and then you’ll be given a special sugary drink to take. After two hours the blood test will be repeated; you mustn’t eat anything else between the two blood tests.
Following the second blood test you can go back to eating and drinking as you would normally. The results of the test are usually available by the following week. If the test is abnormal you will be contacted to discuss this with a Diabetes Specialist Midwife and further appointments will be made for you to see a consultant. See below for an idea of how we monitor you throughout your pregnancy and to get an idea of the frequency of the appointments.
We know that a diagnosis of gestational diabetes can be a disappointment or a shock. Remember your obstetric team want the best for you and your baby, and it is important to understand the risks in order to understand why all the extra appointments are necessary. If we get good control of your diabetes early on you are more likely to have a normal delivery.
Good management of your diabetes will reduce these risks to you and your baby. Some of the risks sound scary but it is important you are well informed about what could happen. Your team will make every effort to reduce these risks and this is why we take it so seriously. Most women with gestational diabetes go on to have healthy pregnancies and healthy babies.
The risks of having gestational diabetes are:
Once you have a diagnosis of gestational diabetes you will have additional appointments, usually first with doctors and then more regular appointments with a diabetes specialist midwife and if necessary further doctor appointments. You will also be offered an appointment with a dietician.
The first and most important step to managing gestational diabetes and controlling your sugar is with diet and lifestyle changes. Many women find that this is all it takes in order to get their sugar levels under control.
The carbohydrates we eat are converted into glucose (sugar), and the rate at which this conversion happens varies depending on the type of carbohydrate eaten. It is important to be aware of how much glucose the food you are eating contains to avoid raising your blood sugar too quickly. There are two forms of carbohydrate:
Slows down the conversion of carbohydrate to glucose, therefore eating more brown rice or wholemeal/brown pasta can help.
A small amount of fat is good for you as it also slows down the conversion of carbohydrate to sugar
Glycaemic index (GI) is a way of scoring food 1-100 according to how they affect your blood glucose. Foods with a high glycaemic index such as potatoes and white bread lead to quick release of sugar and high sugar levels, whereas bran products (e.g. broccoli, brown bread) have a low GI and will raise blood sugar more slowly. The Diabetes UK website has some good information about what types of food fall into which category.
Everyone knows about the sugar in sweets and fizzy drinks, however even healthy food options such as yoghurts and fruits contain sugar. The daily recommended intake of sugar will be different for people of different heights, weights, and ethnic background. For a 2,000-calorie diet, a total sugar intake of 90g, or 24 sugar cubes, is recommended. This includes natural sugars, such as those in rice, milk, and fruit. Added or artificial sugars, such as sweets and fizzy drinks, should only make up about 5% of your diet. This means you should be aiming for a total of 25g or the equivalent of 6 sugar cubes per day of added sugars.
Click here for more information on healthy swaps:
Click here to find out more about Sugarsmart:
One way to lower blood sugar levels is to exercise. When we exercise out muscles take in glucose and our muscles remain more sensitive to insulin for some time. The end result is lower blood glucose levels. Aiming for 30 minutes of moderate physical activity per day can make a big difference. It is important that the exercise isn’t too strenuous, but you should aim for exercise that makes you slightly out of breath with a faster heart rate.
You will be shown how to test your blood glucose level by you team. Here is a summary of the steps:
You will be asked to do this at least twice a day, at the start it is helpful to test more often so we can assess when during the day your sugar levels are high. A dietician can then discuss with you what exactly it might be that you need to avoid eating and suggest some alternatives.
For example it would be ideal to test before breakfast, 1 hour after lunch and 1 hour after dinner for the first few days. And then once a trend is established this can be reduced to twice a day, switching the times you test.
Once you have met with the doctors and the dietician you will often be given a period of time to try and make these changes as best you can. You will then be seen again where the doctors or specialist midwife will look at your blood glucose results to see if the changes have made a difference. In some cases it is necessary to start a medication to help control blood glucose if lots of your readings are still high. These medications have been proven to have no damaging effects for you or your baby.
The medication used is called Metformin, taken up to three times a day. It works by helping your body use the insulin it has and reducing your body’s resistance to insulin. The most common side effects of metformin are some stomach cramps, feelings sick, vomiting, and diarrhoea. The side effects can be reduced by taking the tablet with a meal, or shortly after eating. Metformin is often started at a low dose, which gives your body time to get used to the medication. If, however, the side effects don’t improve or become a problem it is important to speak to your midwife or doctor as there are alternatives. It is also important to remember that not everyone will get side effects and this is just something to be aware of.
Most women with gestational diabetes can be managed with diet and metformin alone. In approximately 20% of patients Metformin doesn’t give the adequate control we would like and so we have to consider using Insulin.
You will need to learn how to give yourself insulin injections, and your midwife will show you how to do this. We know the prospect of lots of injections can seem daunting but don’t be put off. The needles used to give insulin are very different from injections you will have been given in the past; they are very fine and the insulin doesn’t need to be given very deep underneath the skin.
How much insulin you will need and how often will be tailored to you by your diabetes team.
Around 37 weeks onwards your obstetric team will talk to you about a plan for your delivery. This is tailored to each person depending on your sugar control.
In general if your gestational diabetes is controlled by diet alone and if you have no other risk factors it will be recommended that you deliver by 41 weeks.
If you have any other problems or are on Metformin or Insulin, most hospitals will recommend that you deliver by 39-40 weeks.
If you have not gone into labour by these points, induction of labour will be recommended. The main reason for induction is to prevent stillbirth and reduce the chances of the complications mentioned above.
Most women with gestational diabetes have a normal delivery, but it is important you take into consideration the following before you bake a plan for your birth:
All the obstetric team of doctors and midwives will want you to have the birth you hoped for but it is important to remember that things don’t always go to plan. The safety of you and your baby is the most important thing.
Induction involves starting labour off artificially. You can find out more information on this by clicking here.
A Caesarean section (commonly known as a C-section) is not recommended for Gestational Diabetes alone. It is only if there are other factors such as changes to your baby’s growth, or if you develop other complications that it might be recommended. There is currently no evidence that Caesarean sections for the sole reason of having a big baby has any benefits and so is not recommended by most Obstetricians. The doctors will take into consideration your wishes for your birth and no one will force you to do anything. A Caesarean section is a big operation with risks such as bleeding (1 in 200), infection (6%), clots in legs and lungs, and damage to surrounding organs (e.g. Bladder injury 1 in 1000). Therefore, this will only be recommended if the benefits will outweigh these risks.
Booking at 10 weeks: Baseline blood test, HbA1c (a blood test which looks at your overall control; if you have had gestational diabetes in a previous pregnancy you will be offered the Oral Glucose Tolerance Test earlier in your pregnancy)
Offered combined screening/Quadruple test
20 week: Anomaly Scan – detailed scan which can pick up abnormalities in the baby
You will usually have scans 3-4 weekly until term
24 weeks: Oral Glucose Tolerance Test if high risk
Once you have been diagnosed with gestational diabetes the specialist midwife will usually see you or have a phone consultation every 1-2 weeks depending on your control.
28 weeks: Repeat blood test to check for anaemia and to group your blood. Ultrasound scan of Fetal growth and Amniotic Fluid Volume (the amount of fluid around the baby). You will usually see the doctors after this.
32 weeks: HbA1c, Ultrasound scan of Fetal growth and Amniotic Fluid Volume. You will usually see the doctors after this.
34 weeks: FBC (blood test)
36-7 weeks: HbA1c, USS Fetal growth and Amniotic Fluid Volume. You will usually see the doctors after this.
37-39 weeks: Decision to be made about delivery
6 weeks postnatal after delivery: HbA1c by your GP