Fainting in pregnancy 20 weeks and over

Pregnant women can often feel faint. This is due to hormonal changes. Fainting happens if your brain is not getting enough blood and, therefore, not enough oxygen.

You are most likely to feel faint if you stand up too quickly from a chair or when getting out of a hot bath.  It can also happen when you are lying on your back as your bump gets bigger.

When you collapse to the ground, your head and heart are on the same level. This means your heart doesn't have to work as hard to push blood up to your brain. You should return to consciousness after about 20 seconds. Fainting is not usually a cause for concern; however see below for advice about when you should seek advice.


You may experience the following symptoms just before fainting:

• Yawning

• A sudden, clammy sweat

• Feeling sick (nausea)

• Fast, deep breathing

• Confusion

• Light headedness

• Blurred vision or spots in front of your eyes

• Ringing in your ears

This will usually be followed by a loss of strength and you then passing out.

Advice for those around you:

If they have not come round after 1 minute put them in the recovery position (see diagram) and call 999. Ensure they are not lying on their back.


Call 999 for the pregnant women if they have any of the following

  • They have not come round after 1 minute put them in the recovery position (see diagram) and call 999. Ensure they are not lying on their back.

  • They are having any fits or jerking movements

  • They have seriously injured themselves when falling

Contact your maternity unit if you have any of the following:

  • Have fallen and landed on your abdomen (tummy)

  • Have noticed reduced baby movements since fainting

  • Are taking medications for your blood pressure

Contact your GP surgery or NHS 111 out of hours for advice

  • If you have hit your head when falling

  • If this is your first episode of fainting

  • After fainting, it is normal to feel confused and weak for about 20-30 minutes. You may also feel tired and not be able to remember what you were doing just before you fainted. It’s a good idea to rest or not drive your car home.

  • Discuss this with your midwife at your next appointment

  • Click here for more information

Self care

Here are some tips to help avoid feeling faint:

• Try to get up slowly after sitting or lying down

• Eat small regular meals and drink plenty of water (6-8 medium glasses or 1.6L throughout the day) 

• If you feel faint when standing still, find a seat quickly and the faintness should pass – if it doesn't, lie down on your side

• If you feel faint while lying on your back, turn onto your side

It's better not to lie flat on your back in later pregnancy or during labour. The weight of your baby, uterus (womb), amniotic fluid and placenta can press on the main blood vessels that run down your back and can reduce the amount of blood returning to your heart. Lying on your left side is better option for you and for your baby.

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