Last updated:

Reviewed by:

Dr Bryony Henderson

, Lead GP at Livi

Medically reviewed

Preeclampsia affects some pregnant women, usually from 20 weeks of pregnancy or shortly after the baby is delivered. The earlier preeclampsia is diagnosed, the better the result for both mother and baby.

What is preeclampsia?

Preeclampsia is a potentially serious condition that can happen during pregnancy (usually after 20 weeks) or after the birth. It’s characterised by high blood pressure, headaches, and protein in your pee. 

Although many cases are mild, pre-eclampsia should be treated with urgency as it can lead to eclampsia which has life-threatening complications.

Eclampsia is fairly rare in the UK, with an estimated 1 case in every 4,000 pregnancies.

What are the symptoms of preeclampsia?

The earliest signs of preeclampsia are high blood pressure and protein in the urine. These are signs that you may not notice yourself but they are usually picked up during routine antenatal check-ups.

More noticeable preeclampsia symptoms include: 

  • Severe headaches

  • Swelling of your feet, ankles, hands or face 

  • Changes to your vision

  • Vomiting 

  • Abdominal pain

  • Shoulder pain

If you have any of these symptoms, it’s important to get help immediately by calling 111 or speaking to your GP or midwife.

If preeclampsia is left untreated and leads to eclampsia, you’ll experience the same symptoms as preeclampsia but may also develop seizures and loss of consciousness.

What causes preeclampsia?

The cause of preeclampsia is not well understood. It’s thought to be caused by poor development of the placenta (the organ that links mother to baby and allows the baby to feed and receive oxygen).

The placenta needs a good blood supply to work properly, and if it doesn’t get it the placenta may not develop well. This is what’s thought to happen in preeclampsia and this process causes substances to be produced that affect the mother’s blood pressure.

Who is at risk of preeclampsia?

There are various risk factors that can make you more likely to develop preeclampsia during pregnancy. 

These risk factors can be categorised into 2 types – high risk and moderate risk.

 High-risk factors include if you:

  • Have pre-existing high blood pressure (hypertension)

  • Had hypertension in a previous pregnancy

  • Have an existing autoimmune condition (such as lupus)

  • Have diabetes

  • Have chronic kidney disease

Moderate-risk factors include if you:

  • Are older than 40

  • Have a BMI over 35

  • Have gone more than 10 years since your previous pregnancy

  • Have had multiple pregnancies

  • Are in your first pregnancy

  • Have a family history of preeclampsia

If any of these risk factors resonate with you it‘s important that you look out for the symptoms of preeclampsia mentioned above.

How is preeclampsia diagnosed?

Preeclampsia can be diagnosed at a routine antenatal appointment with a blood pressure check and a urine sample. These are routinely checked throughout your pregnancy. 

Your blood pressure is considered high when you have a reading higher than 140 systolic (the top number) or 90 diastolic (the bottom number).

The urine test is carried out to check for any protein in your pee. A dipstick is put into the urine sample you provide and, if there is protein present, the dipstick will change colour to indicate this.

Blood pressure and urine are enough to diagnose preeclampsia. But sometimes a blood test will be conducted to check for a protein called placental growth factor (PlGF) if you are between 20 and 35 weeks pregnant. If the PlGF levels are low, it is possible that you have preeclampsia. If the PlGF levels are high, it’s unlikely.

If you are diagnosed with preeclampsia, you will be sent to a specialist unit within the hospital for continuous observation and treatment.

How is preeclampsia treated?

Preeclampsia is usually managed by monitoring and lowering blood pressure using medicine.

If your blood pressure is still too high, the doctors will start to consider delivering the baby earlier on, for example in the 37th or 38th week. You may be advised to have your baby earlier than this if your health or your baby's health is at risk. 

After delivery, you will be monitored further to ensure that you have not developed any other preeclampsia complications. Early delivery of the baby reduces the chances of this happening.

What happens if I develop eclampsia?

If preeclampsia is left untreated, you can develop eclampsia which can cause fits and loss of consciousness. You may also develop a rare syndrome called HELLP which can affect your liver and blood clotting. Both of these are emergency situations, but they can be prevented with the right treatment.

When to seek help

It’s best to seek help when you notice any of the symptoms listed above. It is also important to remain proactive if you have any of the high-risk or moderate-risk factors that can make you more likely to experience preeclampsia.

Last updated:
Reviewed by:
Dr Bryony Henderson, Lead GP at Livi