Last updated: December 2012
Pre-eclampsia is defined as high blood pressure and excess protein in the urine after 20 weeks of pregnancy in a woman who previously had normal blood pressure. Left untreated, pre-eclampsia can lead to serious, even fatal, complications for both mother and baby .
Accurate pre-eclampsia statistics are difficult to obtain because the condition ranges from extremely mild to severe, and mild cases are sometimes not included in the official figures. Furthermore, mild cases may have no effect on pregnancy, which is why the figures for pre-eclampsia as a whole are higher than for those that actually complicate pregnancies:
• Around 10 percent of pregnant women develop pregnancy-induced hypertension (high blood pressure) or pre-eclampsia (high blood pressure with protein in the urine) .
• Worldwide, more than four million women per year will develop pre-eclampsia  and over 63,000 maternal deaths were due to pre-eclampsia and eclampsia in 2000 .
• Action on Pre-Eclampsia estimates that every year in the UK pre-eclampsia is responsible for the deaths of 500–600 babies, many due to premature delivery rather than the condition itself. Some six mothers die each year from the complications of pre-eclampsia in the UK .
• A 2005–2006 study showed a promising fall in the numbers of women developing eclampsia since 1992, from 4.9/10,000 to 2.7/10,000. This is the result of the introduction of management guidelines and protocols for eclampsia and pre-eclampsia .
• Pre-eclampsia is much more common in first pregnancies , and there is a reduced incidence of pre-eclampsia in the second pregnancy .
• The risk of women who have had pre-eclampsia developing it again in future pregnancies is 16 percent (one in six), rising to 25 percent (one in four) if they suffered from severe pre-eclampsia, eclampsia or they delivered preterm. This rises further to 55 percent (one in two) if their baby was delivered before 28 weeks .
• Half of the women with severe pre-eclampsia give birth to preterm babies .
• Pre-eclampsia is responsible for 15 percent of all preterm births in the USA. Infants of mothers suffering from pre-eclampsia have a five times higher risk of dying than those of mothers without pre-eclampsia, mainly because of preterm birth .
• The symptoms of pre-eclampsia include: severe headache that does not go away with simple painkillers; vision problems (including blurring or flashing before the eyes); severe pain just below the ribs; heartburn that does not go away with antacids; rapid swelling of the face, hands or feet; feeling very unwell .
• All of these symptoms are serious and medical help should be sought immediately.
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Premature birth statistics