Taking any dose of any non-aspirin non-steroidal anti-inflammatory drug (NSAID) early in pregnancy may more than double the risk of a spontaneous miscarriage, a study published recently in the Canadian Medical Association Journal (CMAJ) has warned.
The class of pain relief drug known as non-aspirinNSAIDs, one of the most widely used during pregnancy, yet one that is now raising strong concerns among medical professionals, includes ibuprofen, naproxen, celecoxib and diclofenac, though years of studies to determine the risks have produced inconsistent results, ScienceDaily reported.
To quantify the effects of specific dosages of different non-aspirin NSAIDs, a team of Canadian and French researchers analyzed 4705 cases of spontaneous miscarriage up to the 20th week of gestation, using data from the Quebec Pregnancy Registry (that includes medical and insurance information), and found 352 (7.5 percent) of the women had used NSAIDs, but only 1213 (2.6 percent) of a control group of 47, 050 women who did not miscarry had experienced any exposure to NSAIDs, according to the CMAJ paper.
The women, who were between 15 and 45 years old at the beginning of their pregnancies, were defined as having been exposed to non-aspirin NSAIDs if they had filled one or more prescriptions for any of this class of drugs two weeks prior to the start of pregnancy through the first 20 weeks of gestation.
Ibuprofen is the only non-aspirin NSAID sold over the counter, but women often have it prescribed. For women in the study, Naproxen was the most commonly used of this class of drugs, followed by ibuprofen.
Consistent with results from earlier studies that focused on particular drugs and dosages, the researchers found the NSAID diclofenac alone was associated with the highest risk, and rofecoxib alone with the lowest risk, but lower or higher dosages of NSAIDs appeared to have no effect upon risk.
Speaking for the team, Dr. Anick Bérard, from the University of Montreal noted, "We consistently saw that the risk of having a spontaneous abortion was associated with gestational use of diclofenac, naproxen, celecoxib, ibuprofen and rofecoxib alone or in combination, suggesting a class effect."
The authors concluded, "Given that the use of nonaspirin NSAIDs during early pregnancy has been shown to increase the risk of major congenital malformations1 and that our results suggest a class effect on the risk of clinically detected spontaneous abortion, nonaspirin NSAIDs should be used with caution during pregnancy."
Partly in response to these findings, the Royal College of Midwives and the Royal Pharmaceutical Society are now advising against the use of non-aspirin NSAIDs during pregnancy, the Guardian reported.
According to the U.S. National Library of Medicine PubMed Health reference, other medical research has linked the use of non-aspirin NSAIDs to increased risk of stroke or heart attack,