Preeclampsia is a common complication of pregnancy that is characterized by high blood pressure and loss of protein in the urine. It usually develops in the second half of pregnancy (after 20 weeks) in women whose blood pressure had been normal. It can also occur following delivery of the baby but usually resolves six weeks after delivery. It affects 5-14% of pregnancies worldwide. If left untreated, it can be fatal for both the mother and baby.
Preeclampsia is thought to begin in the placenta (the nutritive organ of the baby). Early in pregnancy, new blood vessels develop and evolve to efficiently send blood to the placenta. In women with preeclampsia, these blood vessels don’t seem to develop or function properly. They are narrower than normal blood vessels and react differently to hormonal signaling, which limits the amount of blood that can flow through them.
Several factors increase a woman’s chance of developing preeclampsia. A personal or family history of preeclampsia, chronic hypertension, first pregnancy, new paternity, age less than 18 or greater than 35, black race, obesity, multiple pregnancy, interval between pregnancies of less than 2 years or greater than 10 years as well as chronic medical conditions all increase the risk.
Preeclampsia can cause complications for both mother and baby. The more severe the condition, the greater the complications. Complications of preeclampsia include fetal growth restriction with attendant low birth weight, preterm delivery, premature separation of the placenta before delivery (placental abruption), eclampsia, HELLP (destruction of red cells, elevated liver enzymes and low platelets), stroke and blood clotting disorder.
Preeclampsia can develop without symptoms. Elevated blood pressure is usually the first sign. It can develop suddenly or gradually. Blood pressure is often measured during the antenatal visit. A blood pressure greater than 140/90 mmHg on 2 occasions 4 hours apart is abnormal. Other signs and symptoms include excess protein in the urine other kidney problems, severe headaches, visual problems such as blurring of vision, temporary loss of vision, right upper abdominal pain, nausea and vomiting, reduced urine output, impaired liver function etc. Sudden weight gain and swelling in the face and hands may occur in preeclampsia but can also occur in normal pregnancies hence not reliable to use this.
If preeclampsia is suspected, some blood tests including blood count, liver and kidney function tests, urinalysis, ultrasound and biophysical profile will be requested for. The most effective treatment for preeclampsia is delivery. Antihypertensives could be given to lower the blood pressure, corticosterioids are given to accelerate baby’s lung maturity if early delivery is anticipated and anticonvulsants in the case of eclampsia. Close monitoring is indicated for those with preeclampsia until delivery is effected. Following delivery, blood pressure monitoring and medication may be continued for weeks till it normalizes.
Preeclampsia may become life threatening to both the mother and her fetus. Prompt recognition of pre-eclampsia and any signs of clinical deterioration, necessitates urgent referral to secondary care to avoid the serious clinical consequences of this condition.