The U.S. Preventive Services Task Force continues to recommend that pregnant women at risk of developing preeclampsia take low-dose aspirin daily, and has expanded the criteria for those at risk.
“I think that this issue has been one that people have talked about and thought about for a long time, but it hasn’t kind of leapt into the front for all practitioners,” Aaron B. Caughey, MD, MPH, PhD, a USPSTF member, said in an interview. “We think it’s really important that all providers and all pregnant persons are aware that folks at an increased risk for preeclampsia can receive a reduction in the risk of preeclampsia from receiving baby aspirin starting after 12 weeks of gestation.”
The task force concluded with moderate certainty that a daily dose of 81 milligrams of aspirin after 12 weeks of pregnancy could reduce the risk for preeclampsia, preterm birth, and stillbirths in pregnant persons at high risk for preeclampsia. The recommendations, which were published in JAMA, are identical to the panel’s 2014 recommendations.
However, the new draft includes a suggestion that expands the list of pregnant patients at risk of developing preeclampsia. In 2014, the USPSTF recommended that clinicians prescribe low-dose daily aspirin to those who had at least two moderate-risk factors related to disparity – first pregnancy, obesity, family history of preeclampsia, lower income, age of 35 years or older, of African descent, and previous adverse pregnancy outcomes. The recent update suggests clinicians consider prescribing low-dose aspirin to patients with just one of the moderate risk factors. The task force also added “in vitro fertilization” as a moderate risk factor.
Dr. Caughey said the motivation for this addition was out of concern for disparities in outcomes for people who have less access to care and to help curb the racial disparity in the prevalence of preeclampsia in Black women and other disadvantaged groups. “[In an effort] to prevent the development of preeclampsia in such individuals that have historically had worse health outcomes, we wanted to emphasize that should at least be considered by clinicians,” Dr. Caughey said.
This change is a “major one,” according to Victor Klein, MD, MBA, CPHRM, a specialist in high-risk pregnancy.
“That’s probably three-quarters of my patients. The majority of my patients will now be candidates [to receive a low-dose aspirin prescription to prevent preeclampsia],” Dr. Klein, vice chairman of obstetrics and gynecology at North Shore University Hospital, Manhasset, N.Y., said in an interview. “[This] may increase the amount of people who will be getting the aspirin and therefore decrease the chance of preeclampsia or developing preeclampsia.”
Preeclampsia is a condition characterized by high blood pressure and signs of problems with the kidneys, liver, and other organs during pregnancy, according to the Centers for Disease Control and Prevention. The condition occurs in about 1 in 25 pregnancies in the United States and can cause serious and fatal complications for both the mother and child.
Although the update reaffirms that aspirin is safe and effective in preventing preeclampsia, Dr. Klein believes the dosage they are recommending is too low, as he has had patients develop preeclampsia while taking 81 mg of aspirin daily. Dr. Klein says he prescribes two daily doses of 81 mg aspirin to some of his patients.
“The majority of us in the field of high-risk pregnancies feel that 81 milligrams is not enough,” Dr. Klein said. “So I am disappointed that [they] didn’t talk about consideration for higher doses. I have patients taking two baby aspirins who developed preeclampsia.”
However, the systematic review that the USPSTF’s recommendation was based on did not “really find evidence to suggest that a higher dose was necessarily better than the lower dose,” Dr. Caughey said. However, this may be something they look at again in the near future.
“I know of clinicians that are asking if we should be using a higher dose,” Dr. Caughey explained. “If more evidence accumulates then absolutely we will look at that issue again.”
In their draft, the task force said there’s limited evidence on the side effects of low-dose aspirin on long-term child developmental outcomes and said the evidence report found no physical or developmental differences in infants at age 12 and 18 months.
USPSTF said comparative effectiveness trials are needed to identify “specific aspirin protocols” and evaluate which dosage, timing, and time of day will have the greatest benefit. The task force also said more research is needed to improve identification of those at an increased risk of developing preeclampsia.
Dr. Caughey and Dr. Klein disclosed no conflicts of interest.