Skip to main content Skip to footer

Pregnancy and diabetes

First of all, what is diabetes?

Diabetes is when there is higher than normal amount of glucose in the blood.

What is gestational diabetes?

Gestational diabetes is a temporary form of diabetes that usually begins
in later pregnancy and usually goes away after you have had your baby. More rarely diabetes may have been present for some time, but is first detected when you are pregnant.

Why does Gestational Diabetes happen?

Two main reasons;
• Firstly, extra hormones produced during pregnancy work against insulin, so your body needs more insulin to do its job.
• Secondly some women may not be able to produce enough insulin to cope with the body’s increased demands.

How common is Gestational Diabetes?

Gestational Diabetes is discovered in 3-5% of all pregnancies – this means about 1 in 25 women will get diabetes in pregnancy. You are at a higher risk of Gestational Diabetes if:
 You have had gestational diabetes in a previous Pregnancy
 You have a family history of diabetes (parent, brother or sister with diabetes)
 You previously had a big baby; over 4.5 kg (10 Ibs)
 You are of South Asian, Middle Eastern, African or Afro-Caribbean origin
 You are over 35 years old
 You have had a stillbirth, or repeated miscarriages
 You have a Body Mass Index over 30
 You are known to have Polycystic Ovaries
 You have extra fluid around the baby

If you have any of these risk factors we recommend you are tested for gestational diabetes during your pregnancy.

How is gestational diabetes treated?

Blood glucose levels may be controlled by changing your diet to reduce added sugars and doing more exercise. If that is not enough tablets and/or insulin treatment will help control your blood glucose levels.

Why is Gestational Diabetes important?

The risks of some complications in pregnancy are increased for both the mother and baby.

The risks to the mother include:
 A higher risk of needing a caesarean section.
 High blood pressure in pregnancy
 Developing diabetes in later life

The risks to the baby include:
 Growing too big and weighing over 4.5 kg (over 10 lbs)
 Difficult delivery due to baby’s size
 Breathing difficulties after birth
 Low blood sugar in the first 48 hours
 Baby may need to go to special care baby unit to help normalise glucose levels
 Becoming obese (overweight) later in life
 A small risk of a stillbirth

Your diabetes-pregnancy team will plan your care with
you to help reduce these risks.

Will my care be different if I have Gestational Diabetes?

Your maternity unit has a special team of midwives, diabetes nurses and doctors who will help care for you and your baby. This means that more of your antenatal care will happen at the maternity unit (or where the pregnancy-diabetes team is based) and your progress during pregnancy will be monitored more closely. Extra antenatal checks and scans may be needed to monitor your baby’s growth. Our aim is to help you have a healthy pregnancy and deliver your baby safely without complications.

This leaflet should only be used with the ongoing advice from your Diabetes Team, as part of your plan of care.

What is healthy eating for diabetes and pregnancy?

• Eat 3 regular meals a day
• Eat at least 5 portions of fruit and vegetables daily
• Eat starchy carbohydrate foods, especially those high in fibre, at each meal
• Eat foods mainly from the four main food groups underlined

  • Fruit & vegetables
  • Bread, cereals, potatoes & other starchy foods
  • Meat, fish & alternative protein foods
  • Milk & dairy
  • Fatty & Sugary foods

• Avoid sugar and sugary foods and drinks
• Limit foods and drinks high in fat and salt

Choosing healthy foods

Fruit and vegetables

Eat at least 5 portions a day
• Good for vitamins, minerals and fibre
• As fruit contains natural sugar have only one portion at a time and spread fruit intake out over the whole day.
• Limit pure fruit juice as it is high in natural sugar (1 small glass, per day with food)
• Vegetables and salad will not affect blood glucose levels and can be eaten freely

A portion is:
3 tablespoons cooked vegetables
1 dessert bowl of salad
A whole fresh fruit eg one apple/pear/orange/banana/peach
2 plums/kiwi/tomatoes
A handful of grapes, strawberries, cherries, raspberries
3 – 4 tablespoons tinned fruit (in natural juice) /stewed fruit/fruit salad

Milk and dairy

3 portions a day
• Good for calcium and protein
• Choose low fat versions eg skimmed and semi-skimmed milk
• If you have soya milk check it contains calcium and is unsweetened

A portion is:
1 glass (180ml) low fat milk
1 carton (150g) diet yoghurt (low sugar)
25g cheese/150g cottage cheese

Meat, fish and alternatives

• Good for protein and minerals especially iron
• Red meat e.g. beef, lamb, pork is rich in iron. Cut off any fat before cooking
• If you cannot eat meat, eat pulses e.g. lentils, dahl, beans several times a week for iron

Includes all types of meat, poultry, fish, eggs, beans, lentils, dahls, nuts, Quorn, tofu, soya, Oily fish (e.g. mackerel, salmon, pilchards) are rich in omega 3. This is good for the heart and your developing baby. Have one portion of oily fish a week.

Foods containing fats and sugars

Eat these only occasionally and in small amounts

• Sugary foods (eg sweets, chocolate, cake, biscuits, icecream) and drinks will cause high blood glucose levels
• Always have sugar-free drinks
• Choose low fat versions where possible 

Healthier fats to choose for heart health:

Oils – rapeseed, olive, groundnut
Spreads – olive or sunflower based
Remember they do contain the same calories as butter so use sparingly!

Starchy Carbohydrate foods

Tip: Choose low GI types of carbohydrate foods 

Eat a moderate amount with each meal
• Good for energy, vitamins, minerals and fibre
• Includes breads, cereals. pasta, rice, potatoes, flour, chapattis, yam, green banana
• High fibre versions will fill you up better and help prevent constipation

Your body turns carbohydrate foods into glucose so they will affect your blood glucose levels.

You need to be careful about the portion sizes you eat. A Dietitian will guide you.

Target blood glucose reading 1 hour after food is less than 7.8 mmol/l

Artificial sweeteners

These can be useful and are safe in normal amounts. Tablet forms include Canderel, Sweetex, Hermesetas. Granulated forms are Canderel Spoonful and Splenda.

Reading food labels

Foods labelled as ‘Sugars 5g or less per 100g’ are low in sugar

Glycaemic (GI) indeGlycaemic (GI) index

Carbohydrate foods are turned into glucose (sugar) at different speeds and may increase blood glucose levels more quickly (high GI) or less quickly (low GI) than simple glucose would.

Eating lower GI foods more often will give better blood glucose control than high GI foods, but care must also be taken with the quantity eaten.

The table below gives the GI rating for the most common foods:

Higher GI foods Lower GI foods
All white and brown bread Granary, wholegrain or seeded bread, Rye/pumpernickel bread
Potatoes – mash, baked Potatoes – new (boiled in skins), Sweet potato (peeled and boiled)
Rice – white Basmati rice, brown rice (steamed)
Most breakfast cereals, Maize meal porridge Porridge oats, low sugar muesli, Special K, All bran
Most biscuits, Rice cakes/crackers Rich Tea, oatcakes, oatmeal biscuit
Glucose Pasta, noodles, bulgar wheat
Sweetened fizzy drinks, Fruit juices Nuts, Beans, lentils, peas, dahls 
Food safety in pregnancy

• liver; all pates; uncooked meats
• raw or undercooked eggs
• mould ripened cheeses e.g. brie, camembert, goats; blue veined cheeses e.g. Stilton
• unpasteurised milk and cheeses
• supplements containing vitamin A.
• shark, marlin, swordfish, raw shellfish

• Limit caffeine to 200mg daily (eg 2 mugs coffee or 4 cups tea or 5 cans Diet pop). Try decaffeinated versions
• limit tuna to 2 steaks or 4 medium cans per week
• limit oily fish to 1-2 portions a week at the most
• ensure all ready meals are reheated until piping hot

Weight gain in pregnancy

Excessive weight gain in pregnancy will not be lost after the birth.

Total weight gain should be 10 -12kg (1 ½ - 2 stone). If your body mass index (BMI) is 30 or more you should aim to limit your weight gain to around 7 kg (1 stone).

Alcohol and pregnancy

Alcohol should be avoided in pregnancy. If you do choose to drink have no more than 1 or 2 units once or twice a week.

This leaflet should only be used with the ongoing advice from your Diabetes Team, as part of your plan of care.

(Hypo = Blood glucose below 3.5 mmol)

Aim to keep blood glucose (BG) readings in pregnancy near normal, i.e.
• Before meals between 3.5 – 5.9 mmol/L
• 1 hour after meal less than 7.8 mmol/L

When you are pregnant:
• You are more likely to have a hypo
• Hypos may happen without warning
• You are less likely to realise or recognise the signs
• The signs of hypos may be different
• You might lose the warning signs completely


Before food BG 3.5
– 5.9mmol/L
1 hour after food BG less than 7.8mmol/L
No hypos 

Not good:

BG less than 3.5mmol/L, Hypo!
You might experience: sweating, shakiness, dizziness, hunger, blurred vision, tingling hands, lips or tongue, difficulty in concentrating, headache 


BG less than 2.0mmol/L, Hypo!
Others might notice that you are moody, irritable, unreasonable or irrational, extreme confusion or unconsciousness can be imminent

Treating a Hypo

NB: It is important you show this leaflet to your partner and family, so you can plan how to deal with serious hypos BEFORE they happen. Act quickly- following this advice:

Severity ACTION 5-10 minutes after What to do next
NOT GOOD: Conscious, Alert, and able to safely swallow food, or drink (BG less than 3.5mmol) Have 15 – 20g quick acting carbohydrate immediately, e.g.
• 5-7 glucose tablets
• 150ml Lucozade, lemonade, fruit juice  or cola (NOT diet drink)
• 4-5 Jellied sweets
Recheck BG. If not returning to normal levels, repeat ACTION with a further 15-20g quick-acting carbohydrate • If 1 to 2 hours till next meal take:
15g of longer acting carbohydrate e.g. slice of bread or a banana
• If more than 2 hours till next meal take 30g of long acting carbohydrate
e.g. have a sandwich
BAD: Not able to safely swallow food, or drink, not alert, may be unconscious, (BG less than 2.0mmol) EMERGENCY SITUATION
You need assistance to
• Assess your conscious level and your ability to self-help.
• DO NOT give anything by Mouth
• You will need a Glucagon injection given by someone else
If Glucagon does not quickly restore consciousness, CALL 999 for paramedic assistance Wait 10mins - if not confused and CONSCIOUS: Give 20g quick acting carbohydrate (Lucozade original 150ml) AND 40g slow acting carbohydrate (2 slices of thick bread)

After a hypo, think back and work out what caused it:

 Did I eat fewer carbohydrates in my meals?
 Was I late eating?
 Was I more active?
 Did I have too much insulin for my food?
 Did I change to different injection sites?
 Was the weather hot?

Safe Driving Diabetes in Pregnancy and Preventing Hypos

• Even If you take insulin for diabetes only during pregnancy, by law you must notify the DVLA (Driver and Vehicle Licensing Agency) that you have been advised to take insulin temporarily
• If you lose awareness of hypoglycaemia you must not drive
• Do not miss or delay meals; carry quick-acting carbohydrate in the car
• Check your blood glucose before you drive and for long journeys stop frequently to test!

If you feel hypo whilst driving :
 Move safely to side of the road
 Stop the car and remove the keys from the ignition
 Move to the passenger seat
 IMMEDIATELY take quick acting carbohydrate
 Follow this with long acting carbohydrate
 Recheck blood glucose. Do NOT resume driving until 45 minutes after your blood glucose has returned to normal (more than 5mmol).

For more information:

This leaflet should only be used with the ongoing advice from your Diabetes Team, as part of your plan of care.

Women with diabetes have less treatment options during pregnancy. Glucose levels can be improved by changing your diet and being more active. Until recently if blood sugar levels rose above safe targets, the only option was insulin injections. A new option is to use Metformin tablets, either on its own or with insulin in lowering blood glucose. Research shows that metformin is safe to take in pregnancy for mother or child. It is effective and will reduce the chances of requiring or needing insulin in many women. In other women the amount of insulin required will be
reduced if metformin is used. The use of metformin in pregnancy has now been recommended by UK national guidelines.

Metformin is available as:
• Metformin 500mg or 850 mg tablets
• Metformin SR (sustained release) 500 mg, 750 mg and 1000mg tablets
• As a dispersible powder and can be taken as a liquid.

Dose: usually 1-2 g daily in divided doses, with food

How Metformin Works

• makes your body more sensitive to the insulin that you make, so your insulin is more effective
• reduces production of extra glucose by the liver
• These good effects lead to more normal blood glucose levels, but does not usually cause low levels. To minimize the chances of tummy side effects metformin tablets must be taken with food, beginning at a low dose and the dose needs to be gradually increased every few days as
prescribed by your doctor.


 SAFE for use in pregnancy
 Provides women with gestational diabetes with another treatment option.
 Does not cause hypoglycaemia (low glucose levels)
 Fewer problems of hypoglycaemia for babies
 A lower insulin dose may be required

Possible side Effects of Metformin:

Some people experience stomach upsets such as nausea, Indigestion, diarrhoea and loss of appetite.

Side effects are minimised by taking metformin either with food or just after eating, and beginning at a low dose. If these problems keep happening the slow-release version might be better for you, discuss with your diabetes team, or your GP.

DO NOT USE > IF YOU HAVE: History of serious kidney, liver, heart or (chest) respiratory disease. 

THINK TWICE > IF YOU HAVE: Nausea & diarrhoea, Pre-eclampsia, Vitamin B12 deficiency. 

CONSIDER > IF YOU HAVE: Gestational Diabetes, Type 2 Diabetes, Polycystic Ovary Syndrome (PCOS). ARE: Overweight & not happy to use insulin, or NEED more than insulin. 

This leaflet should only be used with the ongoing advice from your Diabetes Team, as part of your plan of care.

Once your baby is born

• If you have had gestational diabetes treated with Insulin or Metformin tablets, this will be stopped after delivery of your baby.
• All patients with gestational diabetes will have blood glucose levels checked before going home.
• Your baby may need extra care, i.e. blood glucose monitoring by heel prick test and early frequent feeding, for the first 24 - 48 hours.

Once you are home

• Your blood glucose usually returns to normal. If not, discuss with your diabetes team.
• If you have any questions or concerns about your health or that of your baby, please seek advice from your community midwife.
• A test to see if your blood glucose levels have returned to normal will be arranged, 6 to 8 weeks after delivery. This usually is a Glucose Tolerance test (GTT)

Can you Breastfeed?

• Yes. Breast feeding provides the best nutrition for your child, gives extra protection against infection and helps you to bond with your family.
• For more information ask your midwife for the “Diabetes and Breastfeeding leaflet”.

What is your future risk of Diabetes?

• For most women gestational diabetes goes away after they have had the baby.
• However the chance of developing diabetes later in life remains high and therefore it is important to adopt a healthy life style to prevent diabetes occurring and, if it occurs, to prevent complications later in life.
• If you become pregnant again it is likely you will develop diabetes again. PLAN your pregnancy and tell your doctor as soon as possible.
• It is very important that you should have a glucose tolerance test or fasting blood glucose every year as you have had a pregnancy affected by diabetes. Your GP should organise this for you.
• Detecting diabetes or pre-diabetes (impaired glucose tolerance or impaired fasting glycaemia) can help prevent complications such as heart disease, stroke and kidney disease.

GTT Results after Delivery
Blood Glucose mmol/l What does it mean?
Fasting Value  
6.0 or less Normal: Please follow advice in this leaflet to prevent future diabetes
6.1 to 6.9 Impaired Fasting Glucose: This can lead onto diabetes. Please follow advice in this leaflet to prevent future diabetes
7.0 or more Diabetes is diagnosed in most cases: Specific advice will be given on diet, physical activity, weight reduction and medication
2 Hour Value  
7.8 or less Normal: Please follow advice in this leaflet to prevent future diabetes
7.9 to 11.0 Impaired Glucose Tolerance: Please follow
advice in this leaflet to prevent future diabetes
11.1 or more Diabetes is diagnosed in most cases: Specific advice will be given on diet, physical activity, weight reduction and medication
What can you do?

Irrespective of what the results are, you should:

Exercise more
• Be physically active 30 minutes a day, at least 5 days a week, enough to make you breathless.
• Choose an activity you enjoy. This could be swimming, yoga, walking and jogging.

Eat more healthily
• Make healthy food choices and eat smaller portions.
• Increase fibre intake.
• Choose more fruits and vegetables, beans and whole grains.
• Cut down on sugar and fatty and fried foods.
• Eat at least 5 portions of fruit and vegetables a day.

Achieving Healthy Weight
• After the pregnancy you should try to get your weight into the healthy range.
• It is important to remember that you do need extra energy for breast feeding, so you must consider this if you do decide to try to lose weight.
• You can get help and advice about losing weight and healthy eating from your health visitor, GP or practice nurse.

This leaflet should only be used with the ongoing advice from your Diabetes Team, as part of your plan of care.

Thinking about breastfeeding? Your questions answered

Why should I consider breastfeeding?

• Breastfeeding is the best form of nutrition for babies
• It is especially good if your baby is breastfed for at least 6 months
• It helps you and your baby to build a strong bond

There are plenty of health benefits also:


  • Less risk of ovarian and breast cancer
  • Return to your pre-pregnancy figure faster
  • Less risk of weak bones later in life


Less likely to get:

  • tummy upsets
  • infections e.g. ear, chest
  • eczema
  • asthma
  • obesity
  • childhood diabetes

Breastfeeding is also convenient with no preparation time or temperature checking required. It is also free!

Can I breastfeed?

Yes. Having diabetes should not stop you from breastfeeding your baby.

• If you have gestational or type 2 diabetes, normally controlled without insulin, breastfeeding will be the same as for women without diabetes
• If you normally need insulin to control your diabetes, you will need to be aware of a few extra points of information

Will my breast-milk be the same as milk from a woman without diabetes?

If your diabetes is well controlled, your milk will have the same composition. Insulin does not pass into the breast-milk.

I normally have insulin for my diabetes. What extra care do I need to take if I am breastfeeding?

• You will need to lower your insulin dose immediately after the birth, and monitor your blood glucose levels carefully to get the correct insulin dose
• Hypos will be more likely to occur as you could need up to 40-50g extra carbohydrate daily
• Eat regular meals containing carbohydrate (starch) and always have some food nearby to eat before or during feeds
• Always take a carbohydrate snack with you when you are out with your baby
• You may need a supper snack to cover your baby’s night-time feed
• Continue to monitor your blood sugar levels regularly and seek advice from your diabetes team regarding insulin doses

Can I breastfeed if I am taking tablets for Type 2 diabetes?

You can take either metformin or glibenclamide if you are breastfeeding. The other diabetes tablets should be avoided. Discuss this, and any other tablets you are asked to take, with your diabetes team or your doctor.#

Tips for getting breastfeeding established:

• At 36 -37 weeks of pregnancy you can express and store some colostrum (early milk). This can be given to your baby if he can’t breastfeed after birth or if his/her blood glucose level is low and needs some extra milk. For further advice and support about this ask your midwife in clinic
• Unless your baby needs special care, make sure your baby has skin-to-skin contact with you as soon as possible after the birth
• Whilst you are enjoying this skin-to-skin contact, start breastfeeding. Your colostrum (early milk) is the best food for your baby and will help your baby’s blood glucose to stay at a safe level. Ask the midwife to help you to get your baby latched on correctly
• Continue to breastfeed frequently by baby led feeding, and at least every 2-3 hours
• It will take around 3 days for your milk to come in. In the meantime your baby is getting the vital colostrum which will keep up his/her blood glucose levels

What if my baby needs to go to the Neonatal Unit?

You will be encouraged to visit your baby as often as you wish. At first you will be helped to hand express breast milk so that the vital drops of colostrum can be fed to your baby. Once you are expressing larger amounts of milk you will be able to use a hospital breast pump

More information on breastfeeding

Ask your midwife for the leaflet “Off to the best start – important
information about feeding your baby”. Ask your midwife or health visitor about practical breastfeeding support available locally such as peer counsellors, baby cafes and breastfeeding groups.

National organisations:

You can also get information and support from the following:

• National breastfeeding helpline:
0844 20 909 20

• La Leche League
Helpline : 0845 120 2918

• National Childbirth Trust
Helpline: 0870 444 8708

• Association of breastfeeding
Helpline: 0844 412 2949