Early-onset preeclampsia and HELLP syndrome: An overview

Preeclampsia, one of the "great obstetrical syndromes," affects ~3-5% of pregnancies and is a major cause of maternal and perinatal morbidity and mortality. Preeclampsia is diagnosed after 20 weeks of gestation and is characterized by new-onset hypertension and proteinuria in previously normotensive women, which may deteriorate into maternal multiorgan damage affecting the kidneys, liver and central nervous system. This multisystem disorder is unique to human pregnancy and is the clinical manifestation of heterogeneous pathological processes. The placenta plays a key role in the underlying mechanisms leading to the development of preeclampsia as the only definitive treatment today remains delivery. Early-onset preeclampsia often has severe maternal and foetal consequences including intrauterine growth restriction, preterm delivery, low or very low birth weight, increased perinatal morbidity and mortality and a high incidence of the life-threatening HELLP syndrome, while the clinical presentation of late-onset preeclampsia is frequently mild, resulting mainly in maternal consequences. Of further importance, pregnant women with severe forms of preeclampsia and their growth-restricted foetuses are at an increased risk for developing cardiovascular disease later in life. Here we review the literature on the epidemiology, risk factors, pathophysiology, maternal and perinatal outcomes, diagnosis and management of early-onset preeclampsia and HELLP syndrome and summarize how these severe pregnancy complications are related to foetal growth and health.