Low-dose aspirin reduces preterm preeclampsia in high-risk women
Administration of prophylactic low-dose aspirin during pregnancy may cut the risk of preterm preeclampsia by more than half in high-risk women, suggests a recent study.
“In our study, 1,776 women with singleton pregnancies who were at >1 percent risk of preterm preeclampsia were randomized to receive placebo or aspirin 150 mg daily from 11–14 weeks to 36 weeks of gestation,” reported co-investigator Dr Liona Poon of the Department of Obstetrics and Gynaecology, Chinese University of Hong Kong. “The primary outcome was preterm [before 37 weeks of gestation] delivery with preeclampsia.” [N Engl J Med 2017, doi: 10.1056/NEJMoa1704559]
Results showed a 62 percent reduction in the risk of preeclampsia before 37 weeks of gestation with aspirin vs placebo (1.6 vs 4.3 percent; hazard ratio [HR], 0.38; p=0.004). The risk reduction was even greater for preeclampsia occurring before 34 weeks of gestation (0.4 vs 1.8 percent; HR, 0.18), but was modest for preeclampsia occurring ≥37 weeks of gestation (6.6 vs 7.2 percent; HR, 0.95).
Overall, 25.9 percent of women in the aspirin group and 25.5 percent in the placebo group experienced adverse events (AEs). Headache and/or dizziness was the most commonly reported AE in both groups (9.6 vs 8.8 percent; p=0.59). Serious adverse events were experienced by 1.6 percent of women in the aspirin group and 3.2 percent in the placebo group.
Drug adherence was good in the study, with 79.9 percent of women taking ≥85 percent of the medications.
“Our study showed that the administration of aspirin 150 mg from 11–14 weeks to 36 weeks of gestation resulted in a significantly lower incidence of preterm preeclampsia in women with singleton pregnancies,” concluded Poon.
“Importantly, our study utilized a new algorithm developed by the UK Fetal Medicine Foundation [FMF] to screen for pregnant women at high risk of preeclampsia,” she continued. “Apart from medical history, the FMF algorithm also includes assessment of maternal factors, namely mean arterial pressure, uterine artery pulsatility index and serum placental growth factor.”
“In our previous study conducted in Europe, the FMF algorithm was shown to be superior to the algorithms recommended by the National Institute for Health and Care Excellence [NICE] and the American College of Obstetricians and Gynecologists [ACOG] in identifying women at high risk of preeclampsia who may benefit from low-dose aspirin therapy,” said Poon. “The detection rate with the FMF algorithm was 100 percent, 75 percent and 43 percent for preeclampsia before 32 weeks, before 37 weeks and ≥37 weeks, respectively.” [Ultrasound Obstet Gynecol 2017;49:756-760]
“We have also initiated a prospective study to validate the FMF algorithm in predicting preeclampsia during the first trimester of pregnancy in Asian women,” she added. “The study will include 10,000 women with singleton pregnancies. The recruitment process will hopefully be completed by December 2017.”