preeclampsia

Preeclampsia is a hypertensive disorder of pregnancy defined by new-onset hypertension after 20 weeks' gestation and often accompanied by proteinuria. Diagnostic criteria typically require blood pressure ≥140/90 mm Hg on two occasions at least four hours apart, plus proteinuria (≥300 mg/24 hours) or, in the absence of proteinuria, evidence of end-organ dysfunction such as thrombocytopenia, elevated liver enzymes, renal impairment, pulmonary edema, or cerebral or visual symptoms.

The condition is thought to result from abnormal placentation and placental ischemia, leading to systemic endothelial dysfunction and an imbalance of angiogenic factors (for example, increased sFlt-1 and reduced placental growth factor). Risk factors include primiparity, multiple pregnancy, preexisting hypertension, diabetes, autoimmune disorders, obesity, and advanced maternal age.

Clinical features range from headaches, visual disturbances, and epigastric or right upper quadrant pain to edema; some cases are asymptomatic and diagnosed by screening. Complications for the mother include eclampsia, HELLP syndrome, stroke, renal failure, liver dysfunction, and placental abruption; for the fetus, growth restriction and oligohydramnios.

Management depends on severity and gestational age. For mild disease remote from term, close monitoring and delivery planning at 37 weeks may be appropriate. Severe preeclampsia or delivery indications require hospitalization and delivery. Antihypertensives (such as labetalol, nifedipine, or hydralazine) and magnesium sulfate for seizure prophylaxis are used, with corticosteroids given if preterm delivery is anticipated before 34 weeks to promote fetal lung maturity.

Prevention includes low-dose aspirin in high-risk groups starting early in pregnancy and calcium supplementation in populations with low calcium intake. Prognosis has improved with timely management; recurrence risk exists in subsequent pregnancies.