By Steven Reinberg
MONDAY, Sept. 8, 2014 (HealthDay News) -- Women at high risk for the pregnancy complication known as preeclampsia should take low-dose aspirin daily after 12 weeks of pregnancy, a panel of U.S. health experts recommends.
The recommendation came after the U.S. Preventive Services Task Force (USPSTF) reviewed previous research and found that a daily low-dose aspirin could reduce the risk of preeclampsia by 24 percent in women with a high risk of developing the condition.
"There is good news that pregnant women who are at high risk for preeclampsia can take a low dose of aspirin [81 milligrams per day] to prevent the condition," said task force member Dr. Jessica Herzstein, who is also the global medical director of Air Products and Chemicals, Inc.
"[Daily low-dose aspirin] can reduce the risk of preterm birth by 14 percent and the risk of intrauterine growth restriction -- when a baby grows slower than expected in the mother's uterus -- by 20 percent," she said.
"This results in better outcomes for both the mother and the baby," she said.
Preeclampsia is a complex condition affecting pregnant women and is characterized by a rise in blood pressure and, often, excess protein in the urine after 20 weeks of pregnancy, Herzstein said. The cause of preeclampsia remains unknown, according to the American Congress of Obstetricians and Gynecologists.
Preeclampsia affects as many as 8 percent of all pregnancies, according to the task force. In the United States, about 4 percent of pregnant women develop preeclampsia and this pregnancy complication is responsible for about 15 percent of all preterm births, reports the USPSTF. It also causes approximately 12 percent of maternal deaths in the United States, according to the task force.
"Women at the highest risk for preeclampsia are women who have had preeclampsia during a previous pregnancy, especially those who had complications from it," Herzstein said.
Other women at high risk for the condition are those pregnant with twins, or any multiples, and women with chronic high blood pressure, type 1 or type 2 diabetes, kidney disease or an autoimmune disease, she said.
The task force looked at this issue in 1996, and at that time, didn't recommend aspirin as a way to prevent preeclampsia because there wasn't enough evidence of aspirin's benefit, Herzstein said. "Since then, there have been new clinical trials that show consistently that aspirin can be beneficial for women at high risk," she said.
The current recommendation is for pregnant women at high risk of preeclampsia who don't have any signs or symptoms of the condition, to take a low-dose aspirin daily after the first 12 weeks of pregnancy. A low dose is defined as 81 milligrams per day.
This recommendation only applies to women who can safely take aspirin. The greatest danger linked to aspirin is the risk of stomach bleeding.
Herzstein said it wasn't clear why aspirin has this beneficial effect. "We don't know exactly how this works, but there is consistent evidence among studies that aspirin does provide significant benefits and very small harm," she said. "We need more research to look at how at how aspirin does this."
The task force report was published online Sept. 8 in the Annals of Internal Medicine.
"We don't know what causes preeclampsia, and it isn't clear how aspirin helps," said Dr. Jill Rabin, co-chief of the division of ambulatory care in the Women's Health Programs-PCAP Services at North Shore-LIJ Health System in New Hyde Park, N.Y.
But, she added, "The recommendation looks solid. It looks like the benefits outweigh the risks."