December 9, 2022

Is a common pain reliever safe during pregnancy?


For years, products containing acetaminophen, such as the pain reliever Tylenol, have been widely considered safe to take during pregnancy. Hundreds of widely available over-the-counter remedies, including popular cold, cough, and flu products contain acetaminophen. Not surprisingly, about 65% of women in the United States report taking it during pregnancy to relieve a headache or to relieve a pain in the back.

But recently, a group of doctors and scientists released a consensus statement in Nature Endocrinology Reviews urging greater caution regarding the use of acetaminophen during pregnancy. They noted growing evidence for its potential to interfere with fetal development, possibly leaving lingering effects on the brain, reproductive and urinary systems, and genital development. And while the issue they raise is significant, it’s worth noting that the concerns stem from animal studies and human observational studies. These types of studies cannot prove that acetaminophen is the actual cause of any of these problems.

An endocrine disruptor

Acetaminophen is known to be an endocrine disruptor. This means that it can interfere with the chemicals and hormones involved in healthy growth, which can derail it.

According to the consensus statement, some research suggests that exposure to acetaminophen during pregnancy – especially at high doses or with frequent use – potentially increases the risk of precocious puberty in girls or of male fertility problems such as low sperm count. It is also associated with other problems such as undescended testicles or a birth defect called hypospadias where the opening at the end of the penis is not in the right place. It could play a role in attention deficit disorder and negatively affect IQ.

The risks of adverse effects are low

If you have taken acetaminophen during a current or past pregnancy it can seem quite scary, especially since you have probably always considered this drug to be harmless. But even though experts agree that it’s important to consider potential risks when taking all over the counter or prescription drugs during pregnancy, you should not panic.

“The risk to an individual is low,” says Dr. Kathryn M. Rexrode, head of the division of women’s health, department of medicine at Brigham and Women’s Hospital, affiliated with Harvard.

Chances are, if you took acetaminophen during pregnancy, your baby probably did not or probably will not have any side effects.

Research on this topic is inconclusive. Some information used to inform the consensus statement has been gathered from animal studies or human studies with important limitations. More research is needed to confirm that this drug really causes health problems and to determine at what doses and at what times during pregnancy exposure to acetaminophen may be most harmful.

Sense Steps If You Are Pregnant

Three common sense steps can help protect yourself and your baby until more is learned about it:

  • Avoid acetaminophen during pregnancy when possible. Previously, during preconception and pregnancy counseling, Dr. Rexrode had warned patients against using NSAIDs, such as Advil and Aleve, and suggested taking acetaminophen instead. “Now I also tell people that some concerns have been raised about the use of acetaminophen during pregnancy and explains that its use should be limited to situations where it is really needed,” said Dr. Rexrode. In short, always ask if you really need it before swallowing a pill.
  • Consult your doctor. The use of acetaminophen should always be clear with your doctor, especially if you plan to use the drug for a long time. They might agree that taking it is the best option – or suggest a safer alternative.
  • Minimize use. If you need to take acetaminophen during pregnancy, take it for the shortest time possible and at the lowest effective dose to reduce fetal exposure. “This advice on the lowest dose needed for the shortest period is generally good advice for all over-the-counter medications, especially during pregnancy,” says Dr. Rexrode.

While all of this is great advice for using acetaminophen, there are times when it is more risky not to take it. For example, if you have a high fever during pregnancy, which can harm your baby, acetaminophen may be needed to lower your fever. Provided it is advised by your doctor, the benefits of using acetaminophen in this case outweigh the potential risks.

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