Clinical Pearls & Morning Reports
Most cases of preeclampsia arise at term and are mild and transient and resolve soon after the delivery. However, 5 to 20% of women, especially those in whom preeclampsia arises well before term, have life-altering, life-threatening, or fatal complications. Read the NEJM Review Article here.
Q: What are some of the risk factors for preeclampsia?
A: Maternal biologic and social risk factors for preeclampsia include certain demographic characteristics (e.g., membership in a minority racial or ethnic group), a history of medical or obstetrical disorders (e.g., chronic hypertension), certain characteristics of the current pregnancy (e.g., conception by means of assisted reproductive technology), physiological abnormalities (e.g., increased blood pressure), abnormal results of laboratory tests (e.g., severe anemia), and ultrasonographic abnormalities (e.g., an abnormal uterine-artery pulsatility index, measured by Doppler ultrasonography).
Q: What strategies may be used to prevent preeclampsia?
A: Prevention of preeclampsia is a health care priority, given that only delivery of the placenta has been proved to initiate the resolution of preeclampsia once it has developed. Preventive therapies have been based on the pathogenesis of preeclampsia and focused on redressing angiogenic imbalance, endothelial activation, oxidative stress, inflammation, vasoconstriction, or a combination of these factors. Evidence supports the use of exercise, aspirin, calcium, and labor induction as effective preventive strategies. Aspirin prophylaxis against preeclampsia is associated with a very small increase in antepartum and postpartum bleeding, as well as neonatal bleeding in rare cases. The risks argue against universal aspirin prophylaxis as an alternative to risk screening.
A: Resolution of preeclampsia is initiated with delivery, but maternal end-organ complications may still worsen in the postpartum period, particularly during the first 3 days. Although earlier planned birth minimizes the risk for the mother, it may increase the risk for the newborn, particularly at preterm gestational ages. Currently, no disease-modifying pharmacotherapy is available for established preeclampsia. Randomized trials of potential interventions have focused almost entirely on preeclampsia of early onset and the outcome of pregnancy prolongation. Many trials are under way. Among those targeting pathways involved in the pathogenesis of preeclampsia, one trial, involving 180 women, suggests that metformin (at a dose of 3 g per day) shows particular promise. New approaches include plasmapheresis to remove antiangiogenic factors (i.e., soluble fms-like tyrosine kinase 1 [sFlt-1]), monoclonal antibodies (against tumor necrosis factor α or complement), and gene silencing targeting sFlt-1 production or angiotensinogen.
A: Robust epidemiologic data link preeclampsia with long-term maternal cardiovascular risk factors and disease. Preeclampsia (as compared with a normotensive pregnancy) is associated with an increase by a factor of approximately 4 in the risk of hypertension, particularly within 2 years after delivery, on the basis of data from 15 studies (1646 women with hypertensive pregnancies and 6395 women with uncomplicated pregnancies), as well as approximately twice the risk of type 2 diabetes and dyslipidemia. Preeclampsia at least doubles the odds of cardiovascular disease (on the basis of two systematic reviews of a total of 26 studies), particularly when preeclampsia is severe or recurrent (on the basis of 7 studies involving a total of 52,544 women). In addition, preeclampsia is associated with other health problems, such as seizures, dementia, chronic kidney disease, and even death from any cause.