This sheet talks about exposure to acetaminophen (also known as paracetamol) in a pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.

What is acetaminophen (paracetamol)?

Acetaminophen (paracetamol) is a medication used to treat fever and mild to moderate pain. Acetaminophen is available alone and in combination with other medications to treat symptoms of colds, flu, headache and osteoarthritis. You can buy acetaminophen in different forms, including liquids, tablets, capsules, and suppositories. A common brand name is Tylenol®.

I take acetaminophen. Can it make it harder for me to get pregnant?

Studies have not been done to see if acetaminophen could make it harder for a woman to get pregnant.

I just found out that I am pregnant, should I stop taking acetaminophen?

Talk with your healthcare providers before making any changes to this medication. They can go over the amount of acetaminophen that is recommended for you.

Does taking acetaminophen increase the chance for miscarriage?

Miscarriage can occur in any pregnancy. Based on available studies, taking acetaminophen at the recommended doses is unlikely to increase the chance for miscarriage.

Does taking acetaminophen in the first trimester increase the chance of birth defects?

In every pregnancy, a woman starts with a 3-5% chance of having a baby with a birth defect. This is called her background risk. When used at the recommended dosage, acetaminophen has not been shown to increase the chance for birth defects.

Could taking acetaminophen in the second or third trimester cause other pregnancy complications?

Acetaminophen is considered by most healthcare providers to be the pain reliever of choice during pregnancy. It is best to use only as needed and at the lowest effective dose. Your healthcare providers may have a recommendation of how much they want you to take. The maximum recommended dose of acetaminophen is 4000 mg in one day. Acetaminophen is also in many combination medications. Carefully check the ingredients of any other medications that you take to see if they also have acetaminophen. You will need to add up the amount of acetaminophen in the medications to make sure you are not taking more than 4000 mg in one day.

Taking too much acetaminophen can cause liver damage, kidney damage, and anemia (low iron in the blood) in a pregnant woman. It has also been reported to cause the same problems in the baby.

Does taking acetaminophen in pregnancy cause long-term problems in behavior or learning for the baby?

Some studies have suggested that taking acetaminophen daily or most days during the second half of pregnancy could slightly increase the chance of wheezing or asthma in children. However, other factors may be the reason for the development of asthma in the child, such as the illness the mother has, or why the mother needs to use the acetaminophen during her pregnancy, and not the acetaminophen itself.

There have also been studies that noted a possible association with mild developmental delay (including language delay) and hyperactivity. This association was stronger when acetaminophen was used for 28 days or more during pregnancy. It is not clear if these findings are related to acetaminophen or to other factors.

Another study compared women’s reported use of acetaminophen during pregnancy and then evaluated their children at four years of age. This study did not find an increased chance for harmful effects on the children’s I.Q., learning, or development.

Can I breastfeed while taking acetaminophen?

Acetaminophen is found in low levels in breast milk. When needed, it is given to infants at higher doses than they would get from breast milk. Negative effects in exposed newborns are rare. Be sure to talk to your healthcare provider about your breastfeeding questions.

If a man takes acetaminophen, could it affect his fertility (ability to get partner pregnant) or increase the chance of birth defects?

There is no evidence to suggest that acetaminophen would affect a man’s ability to conceive or increase risk to a pregnancy. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at

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