Fasting in pregnancy

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What is fasting?

Is fasting in pregnancy safe?

Fasting as part of your religion

Talk to your midwife or doctor about fasting

Other things to think about if fasting during pregnancy

Things to watch out for when fasting during pregnancy

What to eat when you break fast

What foods and drinks to avoid when breaking fast

Breastfeeding and fasting

Not fasting in pregnancy helps protect the health of you and your baby. However, it is a personal decision and if you do decide to fast it’s a good idea to speak to your midwife or doctor to get their advice. 

What is fasting?

Fasting is not having any food, or any food or drink, for specific periods of time, or eating a lot less than usual on certain days.

People choose to fast for different reasons. Some fast for health reasons, such as to lose weight. Others may fast as part of their religion or culture.   

Is fasting in pregnancy safe?

Not fasting protects you and your baby, to keep you both well and safe. This is especially important for women and birthing people with pregnancy complications such as gestational diabetes, as fasting can make it difficult to maintain your blood sugar levels. Not fasting makes it easier to drink enough water and eat a healthy balanced diet, so you and your baby get the nutrients you need.

Restricting the calories you have while you’re pregnant is not recommended, whatever your weight is, as this may not be safe for your baby.

Fasting as part of your religion

We can’t be sure that it’s safe for pregnant women and birthing people to take part in religious fasting, such as during Ramadan or Yom Kippur, where a person does not eat any food or drink any fluids, including water, for an extended time.  

Research shows that this kind of fasting is linked with dehydration and tiredness in pregnant women. While it doesn’t affect babies’ birth weight, more research needs to be done to find out whether it has other effects on mums’ and babies’ health.

People who are pregnant or breastfeeding are not usually expected to take part in religious fasting, but it’s a personal decision. When you are used to fasting every year, and your family and friends around you are fasting, it’s understandable to feel like you are missing out.

How long a fast lasts each day will vary based on when Ramadan falls in the year and where you live. This may be something for you to consider when deciding whether to fast.  

Talk to your midwife or doctor about fasting

Talking to your midwife or doctor can help you decide whether to fast and will help them support you if you choose to. They will look at your pregnancy history and talk to you about your weight, lifestyle, how many weeks pregnant you are, and whether you’ve had any complications. This will help them work out how you may cope with fasting and if you need extra support. 

Other things to think about if fasting during pregnancy

• Consider taking a break from fasting every couple of days.  
• Be aware that in the third trimester you need around 200 extra calories each day.  
• Get plenty of rest as you’re likely to have less energy. 

Things to watch out for if you’re fasting during pregnancy

Look out for signs of dehydration such as dark urine, dizziness or weakness, and headaches. Being dehydrated can also lead to urinary tract infections (UTIs) which are common in pregnancy, so watch out for symptoms of a UTI.

Speak to your midwife if you are losing weight. For most people, losing weight is not recommended during pregnancy, so it is best to check.  

It is important that you keep feeling your baby move every day, including when fasting. Most people first feel their baby move when they are 18-20 weeks pregnant. Read more about your baby's movements.

If you feel unwell or that something isn’t quite right, contact your midwife or doctor. Let them know you’re fasting. They should offer non-judgemental advice and care to support you. 

What to eat when you break fast

As with any balanced pregnancy diet, choose a range of healthy foods, including:

• foods rich in vitamins and minerals, such as iron and calcium
• slow-release energy foods, such as wholewheat pasta, oat or bran-based cereals, beans and pulses, unsalted nuts and wholemeal bread
• protein-rich foods, like meat, beans and eggs. 
   

Changing your eating habits and not drinking enough can make you constipated. Have plenty of high-fibre foods when you break your fast, such as wholegrains, fruit, vegetables and beans.

Drink plenty (around 1.6 litres) in between fasting to reduce your risk of dehydration. Remember to take your folic acid (up to 12 weeks of pregnancy) and vitamin D supplements. 

What foods and drinks to avoid when breaking fast

• Caffeine, which can make you feel more dehydrated. It is important to limit your caffeine intake anyway during pregnancy. 
• Acidic or greasy foods that could give you heartburn.
• Too many sugary foods and drinks, as these give you an immediate boost of energy but won’t keep you going.
• Any foods that are unsafe in pregnancy. 

Breastfeeding and fasting

Breastfeeding or chestfeeding is good for you and your baby, if you choose to do it. It protects your baby’s health from birth through to adulthood and has health benefits for you too.  

Women and birthing people who are breastfeeding are not expected to fast, particularly if their baby is under 6 months and exclusively breastfed. But depending on your baby’s age and how you are feeling, you may wish to fast while still breastfeeding.  

If you choose to fast, do speak to a health professional first. They can advise you on foods to help boost nutrients for your breastmilk when you break fast. They may also advise you to fast on a trial basis at first, to watch for any reduction in your milk supply.  

Find out more about breastfeeding your baby.