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What is pre-eclampsia ?


Pre-eclampsia is now referred to as a “syndrome” arising in pregnancy, which can affect the mother, her unborn child or both. In the mother, pre-eclampsia initially causes a number of symptomless (silent) disturbances – including raised blood pressure (hypertension) and leakage of protein into the urine (proteinuria). These symptoms can only be picked up by your maternity care provider by regularly taking your blood pressure during pregnancy and screening your urine. It is important that this is carried out at every antenatal assessment, especially after 20 weeks’ of pregnancy. In a few women pre-eclampsia progresses to a serious illness. The unborn baby may also grow more slowly than expected and can be one of the first signs of pre-eclampsia. Generally, the earlier the onset of pre-eclampsia, the earlier a baby may need to be born. In New Zealand, it can affect from 3-8% of pregnant women which is around 3000 women a year.


Preeclampsia may have no symptoms in its early stages. Your maternity care provider should be checking your blood pressure, screening your urine for protein and also keeping an eye on the growth of your baby. Signs and symptoms of preeclampsia should be discussed with you from 20 weeks. A combination of rising blood pressure and protein in the urine may suggest preeclampsia.


The signs that NZAPEC advise for women to be aware of (and to report to their maternity care provider urgently) are; headaches, visual disturbances (sensitive to light or “flashing lights”), upper abdominal pain, swelling in the face or hands, nausea and vomiting or the baby moving less than usual. These symptoms should never be ignored in pregnancy, although each can have a less serious cause, preeclampsia will need to be ruled out.



All pregnant women should be educated to the signs and symptoms of pre-eclampsia, regardless of how many babies she has given birth to. No one can predict with certainty who will or won’t develop pre-eclampsia. Every woman is at risk in her first pregnancy, although the risk is greater for those with a strong family history of pre-eclampsia. It is important to alert your maternity care provider if you have any family history, especially if your mother or sister(s) have experienced pre-eclampsia. Women who have had pre-eclampsia in a previous pregnancy have an increased chance of pre-eclampsia developing again, so it is important to seek care in pregnancy early, so that you can be referred to a specialist. Pre-eclampsia is also more common with twins. Several existing medical problems, including diabetes, high blood pressure, kidney disease, blood or clotting disorders may also increase the chances for a woman to develop pre-eclampsia.



No one knows for sure. Inherited genetic factors are probably involved, since women whose mothers and sisters have experienced pre-eclampsia are more likely to develop it themselves. What is known is the placenta, the special organ which links a mother to her unborn child, is necessary for pre-eclampsia to occur. The placenta needs a large and efficient blood supply from the mother to sustain the growing baby. In pre-eclampsia, the blood supply to the placenta is reduced, which may lead to placental damage, which triggers changes in the mother’s body. If pre-eclampsia is not detected until it is advanced, this places the woman and baby at risk of serious complications. We can’t express enough how important it is to ensure that you regularly attend your assessments during pregnancy and report any signs and symptoms to your maternity care provider immediately and not waiting until the following day. Although there is not yet a cure for pre-eclampsia, the earlier it is detected gives more opportunity to put specialist care in place to ensure the safe management of your pregnancy and birth of your baby. Pre-eclampsia can occur at any gestation from 20 weeks and the risk of pre-eclampsia developing does not reduce the closer to your due date so it is

important to always be aware of the signs and symptoms of pre-eclampsia all the way through your pregnancy.



Not yet. The only “cure” is to deliver the baby and placenta. Once pre-eclampsia is diagnosed, it becomes a case where the pregnancy needs to be “managed” to keep the baby and mother safe and this sometimes involves bringing forward the baby’s birth earlier than expected. NZAPEC report regularly through our newsletters about research and the advancements in detection, treatment and hopefully one day, a cure for pre-eclampsia.



It really depends on the severity of pre-eclampsia at the time of diagnosis. Sometimes women can be managed as an outpatient with regular appointments with specialists, regular blood pressure and blood tests as well as scans to check on baby. However, most pre-eclampsia diagnoses result in a hospital admission where close monitoring of the mother and baby can be undertaken and ensures that the right medication is given to control blood pressure and to prevent the most serious complications. Treatment with drugs does not “halt” the underlying condition, but can prevent the risk of serious complications occurring. Pre-eclampsia is progressive – it doesn’t get better and can sometimes get worse. Once admitted to hospital, mothers are advised to stay in the hospital for close monitoring until after the birth of their baby.



As the blood supply from the mother to the placenta is restricted, the baby’s supply of nutrients may be reduced. This leads at first to restricted growth and this can also cause distress in the baby. Once pre-eclampsia is suspected or known, the unborn baby is monitored closely to enable birth before any problems become serious. Decisions about birth are particularly important when the baby is very premature.



For the great majority of mothers, birth reverses all the physical effects of pre-eclampsia within days to weeks. One woman in twenty has persistent high blood pressure following pre-eclampsia. Psychological stresses may continue after birth, especially if a mother has been severely ill or had a preterm baby. It is important that you are referred early in your next pregnancy to a specialist to be involved in your care. There is also now strong evidence linking pre-eclampsia to an increased chance of future cardiovascular disease, however, this chance can be modified by lifestyle and by ensuring that women with a history of pre-eclampsia (especially early onset) to check in with their GP yearly for BP, cardiovascular health and heart checks.


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