Pre-eclampsia: The Signs to Know and Why to Get Seen Quickly

A headache that will not shift, rings that no longer fit, a burning feeling under the ribs that you mistake for indigestion. On their own, these signs seem ordinary in late pregnancy. Together, they can point to pre-eclampsia, a pregnancy condition that pushes up blood pressure and can become serious within hours.

The aim here is not to frighten you. The vast majority of cases are moderate, and the condition is picked up early thanks to two simple checks in your antenatal care: measuring your blood pressure and testing your urine. But it is a condition where every hour counts once the signs appear. Knowing them means you can act fast.

What is pre-eclampsia?

It is a condition specific to pregnancy that combines high blood pressure with protein in the urine, a sign that the kidneys are affected. It used to be called toxaemia of pregnancy. Its cause is still unknown, but Geneva University Hospitals (HUG) explain that it starts in the placenta: early in pregnancy, its blood vessels do not develop properly, and it releases substances that damage the mother's body.

It most often appears after 20 weeks of pregnancy, and can also develop in the four weeks after the birth. The earlier it starts, the more often it is severe, the UK's NHS stresses. How common it is varies between European sources: about 2% of pregnancies according to the EFCNI foundation, around 5% according to HUG.

The WHO counts high blood pressure in pregnancy, pre-eclampsia and eclampsia among the five major complications responsible for about 75% of maternal deaths worldwide. That is why health professionals insist on measuring your blood pressure at every visit.

Who is at risk of pre-eclampsia?

Any pregnant woman can develop it, but some factors raise the risk. The NHS sorts them into two groups:

HUG add being under 18 and having a new partner; the EFCNI also mentions assisted reproduction. If any of these apply to you, say so at your very first appointment. Our article on pregnancy after 40 details the closer follow-up that may be offered.

What are the signs of pre-eclampsia?

At first, often none. That is the trap. The first signs, high blood pressure and protein in the urine, cannot be felt: only monitoring picks them up.

As the condition progresses, the NHS, HUG and the EFCNI describe:

• severe, unusual headaches that do not go away with a simple painkiller;
• vision problems: blurred vision, spots before the eyes, flashing lights;
• pain in the upper abdomen, just below the ribs, especially on the right, sometimes spreading to the shoulder;
• sudden swelling of the face, hands, feet or ankles, often with rapid weight gain;
• sudden nausea or vomiting in late pregnancy, heartburn that will not go away, a feeling of being very unwell;
• breathlessness.

Pain under the ribs is often mistaken for reflux. We explain the difference in our article on heartburn during pregnancy. And swelling that sends the scales up within a few days has nothing to do with normal weight gain in pregnancy.

How is pre-eclampsia monitored?

At every antenatal appointment, your blood pressure is taken and your urine is checked, often with a dipstick. If your blood pressure is above 140/90 or protein appears, further tests are done: a blood test to check the kidneys, liver and platelets, and an ultrasound scan to follow the baby's growth, according to the NHS.

Do not skip appointments, even when everything seems fine: screening is useful precisely when you feel nothing. Between visits, a pharmacy or health centre can take your blood pressure if you have any doubt. A home blood pressure monitor is only worthwhile if your doctor asks you to use one, with a measuring method they explain to you.

Can pre-eclampsia be prevented?

Partly, in women at risk. When the doctor or midwife judges the risk to be high, they may prescribe aspirin, to be taken every day from the first trimester until the end of pregnancy. According to the EFCNI, this treatment clearly reduces early pre-eclampsia when started before 16 weeks of amenorrhoea (counted from your last period). The NHS also mentions a calcium supplement when your diet does not provide enough.

Two absolute rules: never start aspirin or calcium on your own, and it is the doctor who sets the dose, when to take it and when to stop. Taking aspirin without medical advice during pregnancy is not a trivial matter.

The rest comes down to lifestyle: a stable weight, a balanced diet and regular physical activity. France's National Authority for Health (HAS) lists preventing pre-eclampsia among the benefits of physical activity during pregnancy. But be careful: once pre-eclampsia has developed, it becomes a reason to stop exercising.

How is pre-eclampsia treated?

The only cure is delivery and the removal of the placenta, HUG explain. Until then, doctors look for the best balance between the mother's health and the baby's maturity:

• treatment to lower blood pressure, suitable for pregnancy;
• in severe forms, treatment through a drip to prevent seizures; the WHO points out that it reduces the risk of eclampsia;
• before 34 weeks, corticosteroids to speed up the maturing of the baby's lungs;
• close monitoring, at home for mild forms or in hospital for severe ones;
• a planned delivery, by induction or caesarean section, sometimes before 37 weeks.

If your baby is born earlier than expected, our article on premature babies helps you understand neonatal care. The signs that mean you should get checked before term are also detailed in our article on threatened preterm labour.

And after the birth?

Blood pressure usually returns to normal in the following weeks, but some women stay on treatment for a while. HUG recommend a check-up about six weeks after the birth to review things.

Pre-eclampsia is also a signal for your future health. According to HUG, the risk of high blood pressure is multiplied by four, and the risks of heart attack, stroke and diabetes are roughly doubled. Have your blood pressure checked every year, cut down on salt, stay active, and mention this history to every new doctor. For your first weeks of recovery, see also our article on the postpartum period.