Urine tests and blood pressure checks in pregnancy

At nearly every antenatal appointment you’ll be asked for a wee sample and have your blood pressure checked. They look like small routine jobs, but they’re how your care team keeps an eye on you.

Why they check

The NHS says your midwife will check your blood pressure at your antenatal appointments, and that your urine is tested too. The checks are for high blood pressure in pregnancy, for the pregnancy condition pre-eclampsia, and for urine infections. The NHS says doctors or midwives check for protein in your urine at each appointment. You’ll be asked for a sample at most appointments from booking onwards.

What counts as high blood pressure?

The NHS describes hypertension in pregnancy as a reading between 140/90 and 159/109mmHg, which may need regular checks but doesn’t always need treatment. Severe hypertension is 160/110mmHg or higher, which needs treatment. High blood pressure often causes no symptoms, so the NHS says it’s important to go to your regular check-ups.

The NHS page doesn’t say whether home monitoring is advised, so ask your midwife if it’s right for you.

What is pre-eclampsia?

Pre-eclampsia is a condition that affects some pregnancies. The NHS says it’s most likely from 20 weeks, but it can happen at any point, and sometimes soon after birth. The early signs are high blood pressure and protein in the urine, and the NHS says you’re unlikely to notice them yourself, which is why the routine checks matter.

You may have a higher chance if you:

have diabetes, high blood pressure, kidney disease or an autoimmune condition such as lupus
had pre-eclampsia in a previous pregnancy
are in your first pregnancy, are 40 or over, or are expecting more than one baby
have a close relative who had pre-eclampsia, or it’s 10 or more years since your last pregnancy
are of Black or South Asian ethnic background, or had a BMI of 35 or more before pregnancy

Having a risk factor doesn’t mean you will develop pre-eclampsia.

For some people at higher risk, the NHS says a midwife or doctor may prescribe a daily aspirin from week 12. Don’t start aspirin or calcium supplements unless your midwife or GP advises it.

When to get help

Contact your maternity unit straight away, day or night, if you are pregnant and have any of these. Don’t wait for your next appointment:

a severe headache that painkillers don’t ease
changes to your vision
pain just below your ribs
sudden swelling of the face, hands or feet
heartburn that does not go away
feeling very unwell, or vomiting

If you have recently given birth, or can’t reach your maternity unit, call NHS 111. If you feel seriously unwell or think it is an emergency, call 999.

If your readings are high

The NHS says if pre-eclampsia is suspected you’re usually referred to hospital for a blood test and scans to check your baby’s growth. Care can include more frequent appointments, extra growth scans and medicine to lower your blood pressure. Treatment doesn’t cure it, but it manages it, and it usually improves after the birth. Ask your team what they recommend and why. See growth scans in pregnancy.

Questions people ask

Do I have to give a urine sample every time?

You’ll be asked for one at most appointments. If you’re not sure why, ask your midwife.

Can I have pre-eclampsia without any symptoms?

Yes. The NHS says it’s unlikely you’ll notice the early signs, which is why the checks matter.

What can I do to help my sample?

Take a sample bottle if you’re given one, and tell your midwife if you’ve had symptoms like pain when you pee.

What if my blood pressure is a bit high at one appointment?

One reading isn’t a diagnosis. Your midwife may check again, and will tell you what happens next.