Can I Take Tylenol While Pregnant? Here’s What The Science Says.

By Émy Roberge & Anick Bérard

You’re pregnant, feeling sore and feverish. You reach for the Tylenol®, then hesitate. Can I take this while pregnant?

If this sounds familiar, you’re not alone. It’s one of the most common question healthcare providers hear. The good news is pregnant people have safely used acetaminophen (the active ingredient in Tylenol® and many store-brand pain or fever relievers) for decades. According to organizations like the Society of Obstetricians and Gynaecologists of Canada (SOGC), it’s the first-choice medication to relieve pain and fever during pregnancy. So, why is it considered safe? Let's sort through what the science says.

The Safety Profile of Acetaminophen

Every pregnancy carries some risks. Miscarriage, birth defects, or premature birth (before 37 weeks of pregnancy) can happen because of many reasons outside of your control. This is called the background risk. When researchers study medications in pregnancy, they look at whether taking medications adds extra risks.

For acetaminophen, large studies including millions of pregnancies show no increased risks of miscarriage, birth defects, premature birth, or babies born with smaller weight than expected.

Some found a possible connection between acetaminophen in pregnancy and autism or ADHD, but these studies have important limits. However, when researchers compared siblings (brothers or sisters who share the same genes and home environment), the link disappeared. This means that acetaminophen itself is probably not the cause. Family genetics or other factors may explain the increase. That’s why acetaminophen remains the first-choice medication for treating pain and fever during pregnancy.

Why Treating Symptoms Matters

It’s easy to focus on what not to take during pregnancy, but leaving fever or pain untreated also carries risks.

A high fever left untreated, especially during the first trimester, can raise the chance of birth defects or miscarriage. Severe pain can affect your sleep, appetite, and stress levels.

Treating your symptoms is important, it’s one way of caring for you and your baby. Your wellbeing matters for a healthy pregnancy.

How to Use Acetaminophen Safely

If you decide to take acetaminophen, the recommendations is to:  

• Use the lowest dose that helps or relieve your symptoms

• Take it for the shortest time; often one dose or a day or two is enough

• Not go over 4,000 mg in 24 hours (maximum daily limit)

• Read the labels, many cold and flu products also contain acetaminophen

• Discuss any questions you have about medication use with your healthcare provider

If you ever take more than you meant to do, call your healthcare provider or poison control, overdose is serious but treatable if caught early.

Common Questions

You might still have questions and that is completely normal.

Acetaminophen taken as indicated is considered safe in all stages of pregnancy, including the first trimester, and while breastfeeding. Only a very small amount passes through breast milk, and side effects in babies are rare.

Ibuprofen (Advil® or Motrin®) or regular-strength aspirin should generally be avoided during pregnancy, especially after 20 weeks. They can possibly affect your baby’s kidneys, heart, and amniotic fluid levels. Some healthcare providers may occasionally recommend them for very specific conditions under medical guidance. If you took ibuprofen before realizing you were pregnant, don’t panic. Just stop and mention it to your healthcare provider.

Check in with your healthcare provider if you need acetaminophen every day for ongoing pain, if your fever is higher than 38.5°C (101.3°F) or for more than two days, or if your headaches don’t get better after taking acetaminophen. Also reach out to your pharmacist or physician if you notice vision changes, swelling, or unusual pain. When in doubt, it’s best to ask. Your healthcare team is there to help you stay safe and comfortable.

The Bottom Line

With so much conflicting information online, it's normal to feel unsure about what's safe during pregnancy. But when you're not feeling well, you don't have to suffer in silence.

Acetaminophen, used as indicated, is a safe and effective option that's been thoroughly studied during pregnancy. If you ever have questions, your doctor, midwife, nurse practitioner, or pharmacist can help you decide what’s best for your situation.

Sometimes the most caring thing you can do for your baby is to care for yourself.

For more evidence-based information, visit http://www.healthypregnancyhub.ca for accessible, expert-reviewed content on medications during pregnancy and breastfeeding. You'll find detailed factsheets and trusted information designed specifically for Canadian families.

The Healthy Pregnancy Hub is funded by the Sex and Gender Institute-CIHR and is designed to supplement, not replace, personalized medical advice.