Painkillers May Raise Miscarriage Risk
Women May Want To Avoid Anti-Inflammatory Drugs While Trying to Get Pregnant
Aug. 14, 2003 -- Taking aspirin or other anti-inflammatory
painkillers around the time of conception or early in pregnancy increases the
risk of miscarriage by as much as 80%, according to a new study.
Although these findings need to be confirmed by further
studies, researchers say that in the meantime, it may be wise for women who are
trying to get pregnant to be aware of this potential risk and avoid using
anti-inflammatory painkillers around conception.
Doctors already recommend that women avoid anti-inflammatory
drugs during pregnancy but this study shows that taking them while trying to
get pregnant may also be ill advised.
Anti-inflammatory painkillers include prescription and
over-the-counter medications that contain the active ingredient ibuprofen
(Advil, Motrin, and others), naproxen (Aleve), and ketoprofen (Orudis KT).
Acetaminophen is a different type of painkiller -- not
anti-inflammatory -- and was not found to carry this same miscarriage risk.
The study appears in the Aug. 16 issue of the British
Painkillers and Miscarriage Risk
Researchers interviewed 1,055 women who had recently become
pregnant about their use of painkillers, including aspirin, other
anti-inflammatory drugs, and acetaminophen (the active ingredient in Tylenol).
About 5% of the women reported using anti-inflammatory painkillers around
conception or early in pregnancy.
After adjusting for other risk factors for miscarriage, the
researchers found that anti-inflammatory drug use increased the women's risk of
miscarriage by 80%. The miscarriage risk was strongest when the painkillers
were taken around the time of conception or if anti-inflammatory drug use
lasted more than a week.
The miscarriage risk for aspirin use around conception or early
in pregnancy was similar, but researchers say it's harder to draw conclusions
because there were only a small number of aspirin users in the study.
Use of acetaminophen, which works in a different way in the
body, had no affect on miscarriage risk.
Anti-Inflammatory Drugs May Interfere With Implantation
Anti-inflammatory drugs suppress inflammation in the body by
blocking the production of substances called prostaglandins, and researchers
suspect this function may also increase miscarriage risk.
Researcher De-Kun Li, of the Kaiser Foundation Research
Institute in Oakland, Calif., and colleagues say animal studies have shown that
prostaglandins are necessary for successful implantation of an embryo into the
wall of the uterus. Prostaglandins are also thought to play an important role
The researchers say the new class of anti-inflammatory drugs
known as Cox-2 inhibitors -- Bextra, Celebrex, and Vioxx -- are not recommended
for use by pregnant women because of embryo implantation problems found in
animal studies. But these effects have not yet been well studied in older
anti-inflammatory drugs, such as ibuprofen.