During pregnancy your blood pressure will be checked at every antenatal appointment. This is because a rise in blood pressure can be the first sign of pre-eclampsia, often called 'pregnancy-induced hypertension' (PIH) or 'pre-eclamptic toxaemia' (PET).
Hypertension affects more than a third of the Australian adult population, the prevalence increasing with age. Many women of child-bearing age are hypertensive, and about 10% of these are diagnosed as having pre-eclampsia. It is more common in first pregnancies.
Your urine will also be checked for protein at every visit, as this is also a sign of pre-eclampsia. Pre-eclampsia usually happens towards the end of pregnancy, after around week 28, but problems can occur earlier. It can also happen during or after the birth. It is likely to be more severe if it starts earlier in pregnancy.
Although most cases of pre-eclampsia are mild and cause no trouble, the condition can get worse and be serious for both mother and baby. It can cause fits (seizures) in the mother, which is called 'eclampsia', and affect the baby’s growth. It is life-threatening for mother and baby if left untreated.
That is why routine antenatal checks are so important to look pre-eclampsia, and protein in your urine.
Many women with pre-eclampsia can hope for a natural vaginal delivery after 37 weeks. But if you have severe pre-eclampsia it may be necessary to deliver your baby early, possibly by caesarean section.
Pregnant women with pre-eclampsia develop the following symptoms first:
- high blood pressure (hypertension)
- proteinuria (protein in the urine).
You probably won't notice these symptoms, but your doctor or midwife should pick them up during your antenatal appointments.
As pre-eclampsia develops, it can cause fluid retention (oedema), which often causes sudden swelling of the feet, ankles, face and hands.
Oedema is another common symptom of pregnancy, but it tends to be in the lower parts of the body, such as the feet and ankles. It will gradually build up during the day. If the swelling is sudden, and it particularly affects the face and hands, it could be pre-eclampsia.
As pre-eclampsia progresses, it may cause:
- severe headaches
- vision problems, such as blurring or seeing flashing lights
- pain in the upper abdomen (just below the ribs)
- excessive weight gain due to fluid retention
- feeling generally unwell.
However, you can have severe pre-eclampsia without any symptoms at all. If you get any of the symptoms listed above, or have any reason to think you have pre-eclampsia, contact your midwife, doctor or the hospital immediately
Symptoms in the unborn baby
The main sign of pre-eclampsia in the unborn baby is slow growth. This is caused by poor blood supply through the placenta to the baby.
The growing baby receives less oxygen and fewer nutrients than it should, which can affect development. This is called 'intra-uterine growth restriction', or 'intra-uterine growth retardation'.
Treatment may start with rest at home, but some women need admission to hospital and medicines that lower high blood pressure. Occasionally, pre-eclampsia is a reason to deliver the baby early - you may be offered induction of labour or caesarean section.
It is vital to go to all your antenatal appointments, or to reschedule them if you can't make it to them, as severe pre-eclampsia can affect both your health and your baby’s health. If left untreated, it can put you at risk from a stroke, impaired kidney and liver function, blood clotting problems, fluid on the lungs and seizures. Your baby may also be born prematurely or small or even stillborn.
While the root cause of pre-eclampsia is not known, studies suggest that the risk is higher if you are overweight when you become pregnant, so it’s a good idea to reach a healthy weight before trying for a baby. It is also more common if you have high blood pressure before becoming pregnant, have had pre-eclampsia in a previous pregnancy, if you are a teenager or older than 35, or if you have diabetes. If this applies to you, attending regular check-ups to have your blood pressure and urine tested is even more important.
Not sure what to do next?
If you are still concerned about your pre-eclampsia or pregnancy-induced hypertension, why not use healthdirect’s online Symptom Checker to get advice on when to seek medical attention. Ensure you attend regular antenatal visits as directed by your health professional and discuss then follow any professional advice given.
The Symptom Checker guides you to the next appropriate healthcare steps, whether it’s self care, talking to a health professional, going to a hospital or calling triple zero (000).
Last reviewed: October 2016