Diabetes and Pregnancy: Gestational Diabetes

This leaflet aims to explain what gestational diabetes (GDM) is, what this means for you and your pregnancy, how you can manage it and outline the care you will receive before and after your baby is born. Please discuss any aspect of your care with us during your clinic appointments or make contact with us with any questions.

The team that will look after you is made up of the obstetrician (doctor specialising in pregnancy), physician (doctor specialising in diabetes), diabetes midwife, diabetes specialist nurse and diabetes specialist dietitian.

What is gestational diabetes?

Gestational diabetes is a condition that can occur in pregnancy when the body becomes less able to regulate the levels of sugar, called glucose, in the blood. As a result, the glucose levels can rise above normal levels.

It typically occurs during the second half of pregnancy although it can occur earlier and usually disappears after your baby is born, which will be checked with a blood test.

Normally, the hormone insulin regulates blood glucose levels within the normal range of 3.5 to 7.8mmol/L.

During pregnancy, the body becomes resistant to the action of insulin, so the body needs to produce more insulin to maintain blood glucose levels within the normal range.

Gestational diabetes occurs when the body is unable to produce enough insulin to meet the extra needs of the pregnancy.

Who is at risk of gestational diabetes?

Any woman can develop gestational diabetes during pregnancy. Sometimes there is no obvious reason for it. Sometimes it is related to a recognised risk factor which can include:

• having had GDM in a previous pregnancy
• having a strong family history for diabetes
• being older (above 40 years)
• being overweight – body mass index (BMI) above 30kg/m2 at booking
• having IVF (in vitro fertilisation)
• some ethnic backgrounds can increase risk (South Asian, Chinese, Black African, Afro-Caribbean, Middle Eastern).

You will be offered screening for gestational diabetes if you have one or more risk factors.

Symptoms of gestational diabetes

Gestational diabetes does not usually cause symptoms. It is often only identified through a screening test.

Symptoms associated with high blood glucose levels include:

• increased thirst
• urinating more frequently
• tiredness

Clinic visits

• The diabetes in pregnancy team will review you every one to four weeks to give help and support.
• If you have a scan on a Tuesday afternoon (after 12.30pm), you will be seen in clinic 21 (Antenatal Clinic) after your scan. Please always attend your scan appointment before coming to clinic 21 for your other appointments.
• If you have a scan on a Tuesday morning (before 12.30pm) or at any other time or day of the week, you will receive a phone appointment to speak with the team.
• If you are booked for a face-to-face appointment on a Monday, please sign in at clinic 21 and then go up one floor to clinic 22 to be seen.

How will gestational diabetes affect my pregnancy?

Some things will happen differently for your pregnancy now that you have gestational diabetes.

• You will need to be very careful with your diet throughout the rest of your pregnancy and during the birth of your baby
• We encourage you to keep active every day.
• You will need to monitor your blood glucose levels four times a day.
• We will offer you extra scans to monitor the growth of your baby.
• You will be seen more frequently in the antenatal clinic. The diabetes team will usually review you every one to four weeks to assess your blood glucose readings and the obstetric team will see you after your scans.
• It is recommended that your baby is born on the Delivery Unit where your labour can be monitored and the staff can meet any additional needs during the birth.
• NICE provide guidance on when your baby should be born depending on how your diabetes has been treated, growth of your baby and blood glucose readings.
• After the birth of your baby you will need to remain in hospital for around 24 hours to allow the monitoring of your and your baby’s glucose readings.

What does having gestational diabetes mean for my baby?

Most women with gestational diabetes have a healthy baby born close to term, however, having gestational diabetes increases the risk of some complications; the two main ones are explained below. We can discuss this with you further during your clinic appointments.

Macrosomia – when the baby is affected by accelerated growth

• One of the major sources of food for your baby is the glucose in your blood. If your glucose readings run above normal levels, the glucose passes directly to your baby. This causes your baby to produce more insulin, and can make your baby grow larger with excess fat stores in unhelpful places such as the waist and shoulders and unhealthy places such as the liver. These excess fat stores have been found to increase the risk of obesity and type 2 diabetes in your child’s future health.
• Having a big baby increases the risk of complications during the birth such as shoulder dystocia (when one or both of your baby’s shoulders get stuck during labour) and can influence when and how your baby is born. The growth of your baby will be monitored closely by extra scans, and we will discuss your birth choices with you towards the end of your pregnancy.
• Keeping your blood glucose readings within the normal range helps prevent these risks.

Neonatal hypoglycaemia – when the baby’s blood glucose levels fall too low after birth

• If your glucose readings are regularly above target levels, the extra glucose passes to your baby and causes your baby to produce more insulin than normal.
• If this happens towards the end of pregnancy, the baby’s glucose levels can fall too low after birth as your baby continues to produce more insulin, and your baby may require extra support to maintain their own glucose levels in the first few days after birth.

To reduce the risk of this happening, keep your blood glucose levels within the normal range up to and during labour. Once your baby is born, skin-to-skin contact as soon as possible after birth and encouraging your baby to feed within the first hour will help stabilise your baby’s glucose levels. Your baby’s blood glucose levels will be checked within four hours of birth and then before the next few feeds which might mean staying in hospital for around 24 hours. We encourage responsive feeding for your baby.

Keeping your blood glucose levels in the normal range allows your baby to grow at the correct rate and keep your baby’s blood glucose levels stable after birth.

Dietary advice

Diet and physical activity are the first, and often the only, form of treatment required for gestational diabetes. Your blood glucose readings can often be maintained within the normal range by eating the recommended dietary choices and by being physically active after each meal.

You will need to follow the dietary guidance for the rest of your pregnancy and during labour.

Carbohydrate foods

• Carbohydrate foods directly affect blood glucose levels and so are the main focus of the dietary treatment.
• When carbohydrate foods are eaten, they are digested and absorbed into the blood stream as glucose, causing the blood glucose levels to rise. The body then produces just the right amount of insulin to cover this rise. This prevents the glucose levels rising above the normal range.
• With gestational diabetes, the body is unable to produce sufficient amounts of insulin, or the insulin that is produced is less efficient, and therefore your blood glucose readings can rise above the normal range.
• To overcome this and keep your blood glucose readings in the normal range it is helpful to avoid refined (highly processed) carbohydrates and to consider the amount of carbohydrate that you eat at a time, often meaning smaller portions more frequently. Avoid skipping meals.
• However, it is important to continue to include carbohydrates in your diet since a healthy balanced diet should contain some carbohydrate food with each meal and snack to provide energy, fibre, vitamins and minerals.
• It important to eat enough carbohydrate for a healthy diet but not too much to overload your insulin production.

Carbohydrate foods include potato, bread, rice, pasta, yam, cassava, noodles, couscous, breakfast cereals, crispbread, foods containing flour (cakes, biscuits, pastry, pizza), fruit, milk, yoghurt, sweets, chocolate and sugar.

The types of carbohydrate to include in your diet and which to avoid are listed below.

Carbohydrate portions

The larger the portion of carbohydrate foods eaten, the higher the glucose levels rise and the more insulin the body needs to cover it. When you have gestational diabetes the body is not able to produce large amounts of insulin at any one time, so will not be able to cover large portions of carbohydrate foods.

An important part of the dietary management is to eat smaller amounts of carbohydrate and spread it out over the day.

• You may be asked to eat smaller meals and have additional snacks in between meals so that you eat the same amount over the day but in smaller, more frequent quantities. See section on suitable snacks.
• Avoid doubling up on carbohydrate foods in one meal, for example do not have bread and potatoes or bread and pasta together.
• It is important that some carbohydrates are included at each meal; they should not be avoided or overly limited to keep blood glucose readings down otherwise you may be hungry. The diet can also become deficient in important nutrients and energy, which can then lead to inadequate weight gain and it is important to remember that healthy weight gain in pregnancy is normal.
• We encourage that you eat to hunger.
• It is not uncommon to lose a little weight in the first few weeks after following these recommendations however we will monitor that this weight loss is not ongoing.
• There will be an opportunity to be reviewed by a dietitian.

Breakfast

Carbohydrate is often not well tolerated at breakfast. Many women need to split what they would normally eat over breakfast and a mid-morning snack; for example, 2 slices of toast would become 1 slice of toast at breakfast and 1 slice of toast mid-morning.

Breakfast choices:

1 slice wholemeal toast with a topping eg poached eggs/ scrambled eggs/ mushrooms/ tomato/ avocado/ cheese/ ham/ other cold meats.

Or: 1 small pot yoghurt (less than 15g total carbohydrate per pot) with one portion of chopped fruit or a cup of berries (optional: can top with nuts or seeds)

Or: 25g jumbo porridge oats mixed with crème fraiche and 1 cup of berries (frozen berries work especially well if all left together in the fridge overnight) optional – top with nuts or seeds.

Or: 40g jumbo porridge oats made into porridge with water and single cream added to taste (may be flavoured with mixed spice, cinnamon or artificial sweetener).

This can then be repeated mid-morning or choose a snack from the list below.

Carbohydrate type

The following table lists the foods identified as being best avoided with suitable alternatives.

• Processed carbohydrates have a high glycaemic index (GI) and cause a faster rise in blood glucose readings and make it harder to keep the 1-hour post-meal glucose readings within the normal range so are best avoided.
• High fibre, unrefined/ unprocessed carbohydrates (low GI) create a slower rise in glucose making them better choices.

Carbohydrate portion for lunch and evening meal:

Please include carbohydrate at each of your meals. The quantity you will tolerate may vary but the following portions are a good place to start; aiming for 40g carbohydrate

• Bread: 2 medium slices / 1 dessert plate sized chapatti or wrap/ 1 medium roll / 1 medium pitta bread
• Cooked rice / pasta / couscous: 4 heaped tablespoons
• Potatoes: 4 egg sized, 3-4 tablespoons mash, 1 small jacket potato
• See menu suggestions below

The following foods and drinks have little impact on blood glucose levels and can be enjoyed in your usual amounts.

• Protein foods such as meat, fish, eggs, cheese, tofu, Quorn, peas, beans and lentils have little, if any, effect on glucose levels and can be eaten freely.
• Non-starchy vegetables and salad vegetables have little, if any, effect on glucose levels and can be eaten freely.
• Eating more protein and non-starchy vegetables or salad with your meals can help stop or reduce hunger.
• Always eating protein foods and/or non-starchy vegetables or salad vegetables with carbohydrates can make the post meal glucose easier to manage and keep post meal blood glucose readings in the target range.
• Carbohydrate-free drinks include tea and coffee with a splash of milk, Bovril and oxo. However, lattes and flat white coffees contain carbohydrate due to their higher milk content and should be kept to between meals rather than with meals.
• You can add flavour and interest to food and meals by using herbs/ spices/ oils/ vinegars and mustard as these have no impact on glucose levels.

Foods labelled as 'Diabetic Foods' are not recommended as part of your diet due to their contents.

Snack choices

The following snacks contain enough carbohydrate to have between meals:

• 1-2 pieces of fruit (one portion of fruit is: 1 small apple/ pear/ peach/ nectarine/ orange/ fun-sized banana, or 2 plums/ tangerines/ satsumas, or 1 cup berry fruit (strawberries, raspberries, blueberries, cherries), or 10 grapes
• 2 whole wheat crispbreads or oatcakes with cheese
• Small pot of yoghurt (less than 15g total carbohydrate per pot)
• 1 slice wholemeal bread sandwich or toast with protein or vegetable topping

The following snacks are carbohydrate-free and can be eaten at any time:

• Natural nuts or mixed seeds.
• Olives.
• Vegetable pieces such as celery, carrots, cucumber with hummus, cream cheese or salsa dips.
• Avocado.
• Cherry tomatoes.
• Cubes of cheese (try with cocktail onion or gherkin), mini mozzarella.
• Sun blushed or sun dried tomatoes.
• Cooked meats.
• Sugar free jelly.
• Small corn on the cob.
• Boiled egg.

Suggested menu changes

Split breakfast

• 7-8am: small pot yoghurt with cup of berries sprinkled with seeds.
• 9-10am: 1 x medium slice of wholemeal toast with protein topping (cheese/ ham/ egg/ peanut butter).

Mid-day meal

• 2 x medium slices wholemeal bread sandwich with protein filling.
• Or soup and wholemeal roll.
• Or as for evening meal.
• 1.5 - 2 hours later: piece of fruit or a yoghurt.

Evening meal

• 4 x egg sized potatoes or 4 x tablespoon cooked rice, pasta or grains with generous portion of protein and plenty of vegetables or salad.
• 1.5 - 2 hours later: a carbohydrate free snack such as vegetable sticks with hummus or cream cheese.

Snacks

• Two carbohydrate containing snacks are suggested across the day between meals.
• Carbohydrate free snacks can be eaten at any time.

Physical activity

You are recommended to be active for 10-15 minutes straight after each meal and large snacks.

• Regular physical activity will improve your body’s sensitivity to insulin and makes it work more effectively, especially if this is straight after meals.
• This is just as important as the dietary changes and can make up to 2mmol/L difference to your post-meal glucose reading.
• Helpful types of activity include: walking, swimming, cycling, being active around the house, dancing, moving legs and/or arms whilst sitting on a chair.
• Structure your day to make space for post-meal activity. This may mean eating a meal a little earlier or getting the support of family and friends to free your time to be active.
• If you are struggling with increasing activity, please discuss this with us during your clinic appointment.

Weight gain

• Being overweight or gaining too much weight in pregnancy can add to the risk of complications associated with gestational diabetes.
• Keeping your weight stable for the rest of your pregnancy after being diagnosed with gestational diabetes can help reduce these risks and make the blood glucose readings easier to manage with diet and activity.
• Many women find that following the diet and lifestyle recommendations for gestational diabetes prevents any further weight gain.
• Eating more protein foods and healthy snacks can help manage hunger.
• If you are concerned about your weight, please discuss this with us during your clinic appointment.

Sleep

Please let us know if you are struggling to sleep at night as this can affect your blood glucose readings overnight and first thing in the morning.

Blood glucose monitoring

You will be asked to monitor your blood glucose levels four times every day:

• Fasting (before eating or drinking anything) and ideally within 5 to 10 minutes of waking.
• One hour after breakfast, lunch and dinner (timed from start of meal).

It is important that you always wash your hands before checking your blood glucose levels to avoid getting false high readings. Wash your hands with soap (without moisturiser or glycerin) and water, and avoid alcohol gels and wipes as these can affect the reading.

The blood glucose levels you are aiming for are listed below:

If you get a reading above target range, please write down what and how much you ate at the meal before or if you were inactive or feeling unwell.

If you get three readings above these targets within 1 week, please make contact with the diabetes in pregnancy team (see contact details below).

Will I need to have medication?

• Not necessarily; many women are able to regulate their blood glucose levels by following the diet and physical activity recommendations above.
• However, some women do not produce enough insulin to cover what they need to eat to support a healthy pregnancy and, in spite of their best efforts, need to start some medication to keep blood glucose readings in the normal range. It is important to remember that needing medication to help your blood glucose readings does not mean that you have failed in any way.

There are two options for medication:

• Metformin is a tablet that enables the insulin you produce to work more effectively. Whilst it is not licensed by the manufacturer for usage in pregnancy, there have been a number of good studies to show it can be used safely in pregnancy and it is recommended for use in pregnancy by NICE (National Institute for Health and Care Excellence). Metformin is a medication that crosses the placenta; if you feel strongly about this please discuss this with us so we can make the right choice.
• Insulin injections to 'top up' the limited amount of insulin your body is able to produce. This may be before bed and/or before meals.

Which is the best choice for you will be discussed with you during your clinic appointment. There is also a leaflet giving more information on medication choices available on request.

Obstetric care

You will be offered additional growth ultrasound scans to monitor your baby at 28, 32 and 36 weeks (or the next available opportunity if already over 28 weeks). You will also have an appointment with the obstetric team to discuss the result of the scan. If your care was previously community-based, you will now be allocated a consultant obstetrician to help plan your care for the remainder of your pregnancy.

It is important to continue to see your community midwife throughout your pregnancy for routine antenatal care.

Baby’s movements: please monitor your baby’s movements carefully and contact the Day Assessment Unit (telephone number 01223 217217) the same day if you note any change or reduction in movements.

Birth

It is recommended by NICE for you to give birth to your baby on the Delivery Unit as this allows for close monitoring of you and your baby and additional medical support is available if required.

• The birth date and plan are likely to be affected by having gestational diabetes. You will have the opportunity to discuss this with the obstetric team and the specialist midwife between 32 and 36 weeks.
• When and how you give birth is influenced by a number of things: your choice, how your gestational diabetes has been managed and the growth of your baby.
• Guidelines produced by NICE recommend that women with gestational diabetes deliver by 40 weeks and 6 days although in some circumstances, earlier delivery would be recommended; for example, if your baby is larger, there is increased fluid or you are requiring insulin. If you do not go into spontaneous labour before your recommended birth time, we will discuss the options for delivery with you and provide you with the additional information.
• You will be advised to deliver on the main Delivery Unit (rather than the Rosie Birth Centre) so that we can offer appropriate monitoring during labour for both you and your baby.
• Birth plans will be discussed with you towards the end of your pregnancy.

Diet during birth

If you are eating during labour, it is important that you keep to the diet you have been following to keep your blood glucose readings within target.

The hospital menu might not be able to support your dietary choices and you may wish to bring some of your own snacks, foods and drinks in with you that you feel will be able to maintain blood glucose readings within the target range. An information leaflet will be provided to you before your hospital admission to help you plan what foods and drinks to pack in your hospital bag.

You and your baby will need to remain in hospital for monitoring for around 24 hours.

Blood glucose monitoring

Continue to check your blood glucose levels during labour and for the first 24 hours after birth. Once your baby has been born, the targets for your blood glucose readings change as below.

If you get readings above these levels, please inform a midwife on the ward.

Infant feeding

Breastfeeding is encouraged as a good option for both you and your baby. If you plan to breastfeed and would like information on colostrum harvesting, please mention this at your 36 week appointment.

What does having gestational diabetes mean for me in the future?

For most women, gestational diabetes disappears once your baby is born. This will be checked with a blood test three months after the birth of your baby at your GP surgery or at the Rosie Hospital; please ensure that you attend for this test. If you chose to have your blood test at the Rosie Hospital and the result is normal, we will write to inform you of this. If the result has remained high, we will invite you back to clinic to discuss the result. If you decide to have your blood test with your GP, please ensure you follow this up to discuss the result.

Please book a glucose blood test with your GP surgery once a year to screen for type 2 diabetes. A good time to remember to do this is in the same month that your baby was born.

Having had gestational diabetes means you are likely to develop gestational diabetes in any future pregnancy and more likely to develop type 2 diabetes in the future.

Future pregnancies

Because of the increased risk for developing gestational diabetes again, you are recommended to eat a healthy diet and get in touch with the diabetes midwife after your dating scan so you can start to monitor for the onset of gestational diabetes.

The guidance is:

• Please check glucose two times each day and vary the testing times over the day including; on waking (within 10 minutes of waking) and 1 hour after the start of main meals. For example, check on waking and 1 hour after lunch on one day and 1 hour after breakfast and 1 hour after evening meal on the next day and alternate these times over the week.
• Contact the diabetes midwife if your glucose readings are above the normal range (above 5.3 mmol/l on waking and above 7.8 mmol/l one hour after meals).
• Continue to eat your normal healthy diet.
• We will routinely see you in clinic at 24 weeks to review your blood glucose readings.
• If you are overweight during your current pregnancy, losing weight before your next pregnancy will reduce your risk of developing gestational diabetes.

Developing type 2 diabetes

Research studies show that women who developed gestational diabetes have a 50-70% chance of developing type 2 diabetes in the future.

Reducing your risk of developing type 2 diabetes

• Your GP is able to refer you to the Healthier You: NHS Diabetes Prevention Programme (NHS DPP).
• Being a healthy weight will significantly reduce your risk of developing type 2 diabetes. If you are overweight, reducing your weight to within a healthy range after your baby is born will help reduce your risk of developing type 2 diabetes. However, do not start a strict weight reducing diet during the pregnancy or whilst breastfeeding. You can ask your GP to refer you to a dietitian or weight reducing programme if you would find this helpful.
• Physical activity makes insulin work more effectively. Including some physical activity into your daily routine for 30 minutes will reduce the risk of developing diabetes. This needs to be additional to your normal daily activity and at a level that makes you breathe harder than normal; for example, a 30 minute brisk walk. This can be divided into smaller time slots if that fits into your routine better.
• Eating a healthy diet that is high in fibre, low in refined (highly processed) carbohydrate and low in saturated fat will help keep your weight in a healthy range. It also reduces the risk of developing type 2 diabetes.
• Breastfeeding is supported by research that shows women with gestational diabetes who breastfeed their babies reduce and delay the risk of developing type 2 diabetes.

Diabetes in pregnancy team contact details

Monday to Friday

• Email the diabetes in pregnancy team
• Diabetes specialist midwife: 01223 586901 (answerphone)
• Diabetes specialist nurse: 01223 348790 (answerphone)
• Diabetes specialist dietitian: 01223 349471 (answerphone)
• Appointments: 01223 217664

Anytime

Maternal Assessment Unit: 01223 217217