The US Food and Drug Administration has recommended that nonsteroidal anti-inflammatory drugs (NSAIDs) not be taken by women in the second half of pregnancy, warning that id could cause rare but serious kidney problems in the unborn baby. In a Drug Safety Communication, the FDA says this could lead to low levels of amniotic fluid and the potential for pregnancy-related complications.

NSAIDs include medicines such as ibuprofen, naproxen, diclofenac, and celecoxib. Aspirin also is an NSAID; however, these recommendations do not apply to the use of low-dose aspirin (81mg). Low-dose aspirin may be an important treatment for some women during pregnancy and should be taken under the direction of a healthcare professional.

“It is important that women understand the benefits and risks of the medications they may take over the course of their pregnancy,” said Patrizia Cavazzoni, MD, acting director of FDA’s Center for Drug Evaluation and Research. “To this end, the agency is using its regulatory authority to inform women and their healthcare providers about the risks if NSAIDs are used after around 20 weeks of pregnancy and beyond.”

The warning follows the FDA’s review of the medical literature and cases reported to the agency about low amniotic fluid levels or kidney problems in unborn babies associated with NSAID use during pregnancy.

After about 20 weeks of pregnancy, the unborn baby’s kidneys begin producing most of the amniotic fluid, so fetal kidney problems can cause low levels of this fluid. Low levels of amniotic fluid,  or oligohydramnios, may be detected after taking the medicine for days or weeks, but it may be detected as soon as two days after initiation of regular NSAID use. This condition usually goes away if the pregnant woman stops taking the NSAID.

For prescription NSAIDs, the FDA is requiring changes to the prescribing information to describe the risk of kidney problems in unborn babies that result in low amniotic fluid and to recommend that NSAID use be limited between about 20 weeks to 30 weeks of pregnancy because of this risk. Warnings to avoid taking NSAIDs after about 30 weeks of pregnancy are already included in the prescribing information because taking these medications during this time may lead to heart issues in the unborn baby. If a healthcare provider believes NSAID use is necessary between about 20 and 30 weeks of pregnancy, use should be limited to the lowest effective dose and shortest duration possible, the FDA says.

Source: FDA