Blood pressure should be checked at every prenatal visit to screen for preeclampsia, according to a new recommendation from the U.S. Preventive Services Task Force.
The USPSTF commissioned a review of the current literature to update its initial recommendation regarding preeclampsia screening, which was issued in 1996. The update was considered important “given changes to screening, diagnosis, and management practices, as well as population health, over the past two decades.”
However, the evidence regarding different screening approaches is still quite limited, and the USPSTF did not change its recommendation except to indicate blood pressure checks at every visit rather than “periodically.” The current advice is a “B” recommendation, meaning that the USPSTF recommends the service.
Blood pressure assessment remains the most reliable, least harmful strategy for identifying preeclampsia as early as possible, said Kirsten Bobbins-Domingo, MD, PhD, chair of the USPSTF and lead author of the recommendation statement, and her associates.
“The USPSTF concludes with moderate certainty that screening for preeclampsia in pregnant women with blood pressure measurements has a substantial net benefit,” the researchers wrote ().
The evidence report supporting this recommendation included 21 studies involving 13,982 pregnant women. But no studies directly compared the effectiveness of blood pressure screening between screened and unscreened populations, Jillian T. Henderson, PhD, of Kaiser Permanente Center for Health Research, Portland, Ore., and her associates said in the report.
Fourteen studies assessed tests for protein in the urine to identify preeclampsia, but the accuracy of such tests was highly variable. Sensitivity ranged from 22% to 100% and specificity ranged from 36% to 100%, so the USPSTF did not recommend urine testing for proteinuria as a screen for preeclampsia.
In addition, Dr. Henderson and her associates reviewed four studies (involving 7,123 women) assessing 16 different risk-prediction models. Again, the findings did not support the routine use of such tools in clinical practice: their positive predictive value was just 4% in the largest validation cohort, the investigators reported ().
The American College of Obstetricians and Gynecologists recommends monitoring blood pressure at every prenatal visit to screen for preeclampsia, as well as obtaining a detailed medical history to assess risk factors for the disorder. In contrast, the Society of Obstetricians and Gynaecologists of Canada and the National Institute for Health and Care Excellence in the United Kingdom recommend urinalysis for proteinuria in addition to blood pressure screening.
The full recommendation statement and evidence report are available at.