Fasting in pregnancy

Women may choose to fast for a variety of reasons. Some may be dieting or fasting for weight loss. It is important to know that fasting during pregnancy is not recommended. This is because you need to drink enough water and eat a healthy balanced diet, so you and your baby get the nutrients you need.

Some people fast for religious reasons, but usually pregnant women and women who are breastfeeding are not expected to take part. We would recommend that you don't fast during pregnancy for 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.

Fasting as part of your religion

Not fasting protects you and your baby, to keep you both well and safe. This is especially important for women with pregnancy complications such as gestational diabetes, as fasting can make it difficult to maintain your blood sugar levels. We have information on fasting, Ramadan and pregnancy.

What if I decide to fast during pregnancy?

If you decide to fast, it’s important to get advice from your midwife or doctor. 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 will cope with fasting and if there is any extra support you will need.

If you do decide to fast, consider taking a break from it every couple of days. Be extra careful if you’re fasting during the third trimester as this is a time when you may need 200 extra calories if you are active . Get plenty of rest while you’re fasting as you’re likely to have less energy.
  

Breastfeeding and fasting 

Breastfeeding is beneficial for your baby as it provides them with important nutrients and protection from infections. Women who are breastfeeding are not expected to fast, particularly if your child is under 6 months and is exclusively breastfed. However, depending on your baby’s age and how you are feeling, you may wish to fast while still breastfeeding. 

If you choose to fast, it is important to speak to a health professional first. They can advise you on appropriate foods to help boost nutrients for your breast milk when you break fast. You may also be advised to fast on a trial basis at first, to watch for any reduction in your milk supply. 

Find out more about breastfeeding your baby.  

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.

Any changes you make to your eating habits and lack of fluids can make you constipated. Have plenty of high-fibre foods when you break your fast, such as wholegrains, fruit, vegetables and beans.

Make sure to drink plenty of fluids when you’re not 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, as it 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.

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

• Watch 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. 
• Try to weigh yourself regularly at home and speak to your midwife if you are losing weight. For most women, losing weight is not recommended during pregnancy, so it is best to check. 
• If you feel generally unwell or feel that something isn't quite right, contact your midwife or doctor.