<Tr> <Th> Frequency </Th> <Td> 2--8% of pregnancies </Td> </Tr> <Tr> <Th> Deaths </Th> <Td> 46,900 hypertensive disorders in pregnancy (2015) </Td> </Tr> <P> Pre-eclampsia (PE) is a disorder of pregnancy characterized by the onset of high blood pressure and often a significant amount of protein in the urine . When it arises, the condition begins after 20 weeks of pregnancy . In severe disease there may be red blood cell breakdown, a low blood platelet count, impaired liver function, kidney dysfunction, swelling, shortness of breath due to fluid in the lungs, or visual disturbances . Pre-eclampsia increases the risk of poor outcomes for both the mother and the baby . If left untreated, it may result in seizures at which point it is known as eclampsia . </P> <P> Risk factors for pre-eclampsia include obesity, prior hypertension, older age, and diabetes mellitus . It is also more frequent in a woman's first pregnancy and if she is carrying twins . The underlying mechanism involves abnormal formation of blood vessels in the placenta amongst other factors . Most cases are diagnosed before delivery . Rarely, pre-eclampsia may begin in the period after delivery . While historically both high blood pressure and protein in the urine were required to make the diagnosis, some definitions also include those with hypertension and any associated organ dysfunction . Blood pressure is defined as high when it is greater than 140 mmHg systolic or 90 mmHg diastolic at two separate times, more than four hours apart in a woman after twenty weeks of pregnancy . Pre-eclampsia is routinely screened for during prenatal care . </P>

Complications associated with abnormal values for fetus and/or mother
find me the text answering this question