10 pregnancy myths

You don’t need to eat for two, flying is usually fine and you can dye your hair. Find out the truth behind 10 of the most misunderstood pregnancy myths.

Myth 1: You can't exercise

Exercise is good for you in pregnancy and is not dangerous for your baby. As long there are no complications, you should be able to continue with most exercises you did before getting pregnant. You may need to slow down as your pregnancy progresses or if your maternity team advises you to. There are also a few exercises to avoid in pregnancy

If you were not very active before you became pregnant, start with gentle exercise, such as walking. You can also try this introduction to pregnancy yoga. Yoga has been shown to help you with your physical and mental health during pregnancy and through birth. Find out more about exercise in pregnancy.

Myth 2: You can't dye your hair

Research (though limited) shows it is safe to colour your hair in pregnancy. The chemicals in hair dye are not highly toxic. 

Some studies have found that very high doses of the chemicals in hair dyes may cause harm. But the amount you may be exposed to when colouring your hair is very low.  

You should always carry out a patch test before using a permanent or semi-permanent hair dye, even if you are using your regular brand.  Ask your hairdresser to do a patch test if you are in a salon. Read more about hair dye and pregnancy.

Myth 3: You should eat for two

Needing to eat for 2 during pregnancy is a myth. Your body doesn’t need any extra calories until the third trimester, when you may need around 200 more per day.  Have a look at what 200 calories looks like.

It is important to listen to your body and try to eat a healthy, balanced diet during pregnancy. Try not to put too much focus on counting calories. Just know that your baby doesn’t need you to eat lots more to give them all they need to grow. 

Take a look at our 10 snacks for added energy during pregnancy. 

Myth 4: You can't fly on an aeroplane during pregnancy

Flying isn't harmful to you or your baby. But you should talk to your midwife or doctor about any health issues, complications or concerns you have before booking anything. 

After week 28 of pregnancy, the airline may want a letter from your midwife or doctor confirming your due date, and that you aren't at risk of complications. Check your airline’s policy online before you book anything.

It’s also a good idea to make sure that your travel insurance covers you in pregnancy and that you take your medical notes with you. 

Read more about flying in pregnancy.

Myth 5: You can't have sex while pregnant

It’s safe to have sex when you’re pregnant unless your doctor or midwife has told you not to. For example, if you have had bleeding, have a low-lying placenta or cervical weakness, you may be advised to avoid having sex until after having your baby. 

It’s normal for your sex drive to change in pregnancy. Some enjoy sex during pregnancy and others don’t.

Later in pregnancy, an orgasm, or sex itself, can sometimes trigger Braxton Hicks contractions. This is normal but don’t hesitate to talk to your midwife if you have any concerns. 

If you or your sexual partner are having sex with other people during your pregnancy, it's important to use a barrier form of contraception, such as a condom, to protect you and your baby from sexually transmitted infections (STIs). 

Read more about having sex during pregnancy

Myth 6: You will be glowing and happy all the time

Unfortunately, not everyone will feel very ‘glowy’ during pregnancy. Pregnancy is an emotional time, and your hormones can cause highs and lows in your mood. You may also be coping with pregnancy symptoms and worrying about giving birth or adjusting to parenthood. It can be overwhelming, so if you are not feeling the glow. 

If you are struggling with your feelings, try talking to your midwife or doctor. They will not judge you for how you feel and you are not alone. Up to 1 in 5 women in the UK develop some form of mental health problem, such as anxiety and depression, during their pregnancy or in the year after birth. 

Find out when you should talk to a midwife about anxiety or feeling down in pregnancy.

Myth 7: You will have strange cravings

What do you mean, you’re not craving pickles?! Pregnancy is different for everyone, so not everyone will have cravings. 

We don’t know why some people have cravings, but they are probably triggered by hormonal changes in your body, which can affect taste and smell. 

Speak to your midwife or doctor if you crave inedible things, such as dirt, clay or laundry detergent. This is a serious condition called pica, which is caused by a lack of iron (anaemia).  

Find out more about cravings in pregnancy

Myth 8: Your baby will arrive on their due date

Your due date is useful to help you plan, especially for maternity leave, but remember that the date is only an estimate. It is common for babies to be born after their estimated due date, particularly for first pregnancies. 

If your baby is born before 37 weeks, this is called a premature or preterm birth. If you are at risk of premature birth, your doctors will support you to make sure that your baby gets all the extra care they need. Find out more about premature labour and birth

Myth 9: You can't touch cats

Some people worry that cats can give them an infection called toxoplasmosis, which can be dangerous during pregnancy. But stroking a cat or having a cat as a pet puts you at no greater risk of catching an infection called toxoplasmosis

However, you can catch toxoplasmosis from the poo of infected cats. So try to avoid changing the litter box yourself or use gloves if you do. Touching contaminated cat poo (for example, by changing the litter box) and then touching food can put you at risk.  

There are lots of things you can do to prevent toxoplasmosis and other infections in pregnancy.

Myth 10: Morning sickness only happens in the morning 

Pregnancy sickness is often worse when you first wake up, which is why it is called morning sickness. But it may affect you at any time of day or night or you may feel sick all day long. 

If you can’t keep any food or drink down, or you are worried at all about pregnancy sickness, see your midwife or doctor. You may have a condition called hyperemesis gravidarum.

Remember, every pregnancy is different and you may not have any morning sickness.

NHS. Exercise in pregnancy. https://www.nhs.uk/pregnancy/keeping-well/exercise/ (Page last reviewed 20 January 2020 Next review due: 20 January 2023)

Newham JJ, et ak (2014). Effects of Antenatal Yoga on Maternal Anxiety and Depression: A Randomized Controlled Trial. Depression and Anxiety 2014 Aug;31(8):631-40. doi: 10.1002/da.22268. Epub 2014 Apr 30. PMID: 24788589. 

NHS. Is it safe to use hair dye when I’m pregnant or breastfeeding? https://www.nhs.uk/common-health-questions/pregnancy/is-it-safe-to-use-hair-dye-when-i-am-pregnant-or-breastfeeding/ (Page last reviewed 1 July 2021 Next review due: 1 July 2024)

NHS. Hair dye reactions. https://www.nhs.uk/conditions/hair-dye-reactions/ (Page last reviewed 27 October 2021 Next review due: 27 October 2024)

NICE (2010) Weight management before, during and after pregnancy. Public health guideline PH27 National Institute for health and care excellence https://www.nice.org.uk/guidance/ph27

NHS. Travelling in pregnancy. https://www.nhs.uk/pregnancy/keeping-well/travelling/ (Page last reviewed: 12 November 2018 Next review due: 12 November 2021)

NHS. Sex in pregnancy. https://www.nhs.uk/pregnancy/keeping-well/sex/ (Page last reviewed: 16 March 2021 Next review due: 16 March 2024)

Royal College of Obstetricians and Gynaecologists (2017) Maternal Mental Health – Women ’ s Voices: https://www.rcog.org.uk/globalassets/documents/patients/information/maternalmental-healthwomens-voices.pdf

NHS Start 4 life. Week-by-week guide to pregnancy. https://www.nhs.uk/start4life/pregnancy/week-by-week/1st-trimester/week-5/

Oberg A, Frisell T, Svensson A, Iliadou A. (2013) Maternal and fetal genetic contributions to postterm birth: familial clustering in a population-based sample of 475,429 Swedish births. American Journal of Epidemiology. 177(6):531-537: https://academic.oup.com/aje/article/177/6/531/160108 

World Health Organisation (2015) Toxoplasmosis Fact Sheet http://www.euro.who.int/__data/assets/pdf_file/0011/294599/Factsheet-Toxoplasmosis-en.pdf?ua=1

NHS. Vomiting and morning sickness. https://www.nhs.uk/pregnancy/related-conditions/common-symptoms/vomiting-and-morning-sickness/ (Page last reviewed 13 April 2021 Next review due 13 April 2024)

Review dates
Reviewed: 25 April 2022
Next review: 25 April 2025