Blood pressure during pregnancy

Why it's important to keep a close eye on your blood pressure during pregnancy.


While you’re pregnant, your blood pressure will be checked at every antenatal appointment. Maybe you’ve never really paid attention to it before – so why is your blood pressure suddenly so important?


What is my blood pressure?

It’s a measure of the function of your heart and blood vessels, and gives information about the condition of both.

Your blood pressure is written as two separate numbers. The first, the systolic pressure, is the maximum pressure in an artery at the moment when the heart is beating and pumping blood through your body.

The second, the diastolic pressure, is the lowest pressure in an artery in the moment between beats – when the heart is resting.

If either of these numbers is raised, it can indicate high blood pressure (hypertension).

Your blood volume increases by 70% during pregnancy, placing greater strain on your cardiovascular system. Low blood pressure is common around week 32, and it can make you feel faint and dizzy. High blood pressure can indicate pre-eclampsia, a potentially serious condition.

What if my blood pressure is high?

Your midwife will take a repeat test and also check your urine for protein. Traces of protein combined with high blood pressure can indicate pre-eclampsia.


If your blood pressure is over 140/90 or is unusually high for you, you’ll need monitoring in hospital. You’ll also have blood and urine tests, plus scans to check your baby.


Please read our Chat guidelines.