How to Read Pregnancy and Lactation Drug Labels in 2026

Posted By Kieran Beauchamp    On 20 Jan 2026    Comments (12)

How to Read Pregnancy and Lactation Drug Labels in 2026

For years, doctors and patients relied on simple letters-A, B, C, D, X-to decide if a drug was safe during pregnancy. But those letters didn’t tell the whole story. In fact, they often made things worse. A ‘C’ rating didn’t mean ‘maybe dangerous’-it meant ‘we don’t have enough data, but we can’t rule out harm.’ And that’s not helpful when you’re trying to decide whether to keep taking your antidepressant or seizure medication while pregnant.

Why the old system failed

The old pregnancy letter categories were introduced in 1979. Back then, they made sense. There wasn’t much data. But by 2015, we had decades of real-world evidence. The problem? People treated those letters like grades. A was ‘safe.’ X was ‘never use.’ But that’s not how risk works.

Less than 2% of drugs were Category A. That didn’t mean they were the only safe ones. It meant there were enough human studies to prove no harm. Most drugs fell into C-about 70%. That left doctors guessing. Was a C drug riskier than a B? Not necessarily. Was an X drug always dangerous? Sometimes, yes-but not always. For example, isotretinoin (Accutane) is X because it causes severe birth defects. But some cancer drugs are also X, and in rare cases, the benefit to the mother outweighs the risk to the baby.

The old system didn’t explain background risk. Every pregnancy carries a 3% chance of major birth defects, no matter what you take. It also carries a 10-20% chance of miscarriage. The letter system ignored all of that. It didn’t say when during pregnancy a drug might be risky. It didn’t tell you how much of the drug gets into breast milk. And it didn’t mention if there were registries tracking outcomes.

The new system: PLLR explained

In June 2015, the U.S. Food and Drug Administration replaced the letter system with the Pregnancy and Lactation Labeling Rule (PLLR). This wasn’t just a tweak-it was a complete overhaul. Now, every prescription drug label has three new sections under Section 8: Use in Specific Populations.

These are:

  1. Pregnancy (8.1)
  2. Lactation (8.2)
  3. Females and Males of Reproductive Potential (8.3)

Each section follows the same three-part structure: Risk Summary, Clinical Considerations, and Data. No more guessing. No more letters. Just facts, numbers, and context.

Reading the Pregnancy section (8.1)

Start with the Risk Summary. This is where you’ll find real numbers. For example:

“The background risk of major birth defects in the U.S. general population is 2-4%. In women exposed to sertraline during the first trimester, the risk of major congenital malformations was 3.1% (95% CI: 2.5-3.9%), compared to 2.9% in unexposed women.”

That’s not vague. That’s precise. It tells you:

  • What the normal risk is
  • What the risk was in the study
  • Whether the difference is statistically meaningful

Next, look at Clinical Considerations. This is your action plan. It answers:

  • When during pregnancy is the drug riskiest? (e.g., “Risk of cardiac defects highest between weeks 4-8”)
  • Do you need extra monitoring? (e.g., “Fetal echocardiogram at 20 weeks if used after week 12”)
  • Should you switch medications? (e.g., “Consider switching from valproate to lamotrigine before conception”)

Finally, the Data section tells you how the evidence was gathered. Was it a registry? A case-control study? A cohort of 500 women? Was the data adjusted for smoking, age, or other medications? This matters. A single case report isn’t the same as a 1,200-woman study.

One key change: pregnancy exposure registries are now required. If a drug has one, it will say so. For example, the Antiepileptic Drug Pregnancy Registry tracks over 5,000 pregnancies annually. These registries help fill gaps in data-especially for drugs used by women with chronic conditions.

Understanding the Lactation section (8.2)

This section answers one question: “If I breastfeed, how much of this drug will my baby get?”

Look for numbers like:

“Maternal serum concentration: 150 ng/mL. Infant serum concentration: 8 ng/mL. Infant exposure: 5.3% of maternal weight-adjusted dose.”

That’s a lot clearer than “may be excreted in breast milk.”

It also tells you:

  • Is there evidence of side effects in infants? (e.g., “One case report of drowsiness in a 3-week-old infant”)
  • Is there a preferred timing? (e.g., “Take dose immediately after breastfeeding to minimize infant exposure”)
  • Are there alternatives with lower transfer? (e.g., “Lamotrigine has lower milk-to-plasma ratio than valproate”)

Some drugs, like certain chemotherapy agents or radioactive compounds, are still contraindicated during breastfeeding. But most aren’t. The FDA now requires manufacturers to include pharmacokinetic data-how the drug moves through the body-so you can make informed choices.

A pharmacist robot handing a pregnant woman a holographic drug label with floating risk percentages and a protective fetal bubble.

Reproductive Potential (8.3): More than just pregnancy

This section is often overlooked, but it’s critical. It covers:

  • When to test for pregnancy before starting treatment
  • What contraception methods are recommended (and their failure rates)
  • Whether the drug affects fertility
  • Whether male partners need to take precautions

For example, finasteride (Propecia) can cause birth defects if a pregnant woman is exposed to it. So the label now says: “Men taking finasteride should not donate sperm during treatment and for 6 months after discontinuation.”

Or take isotretinoin: “Females must have two negative pregnancy tests before starting, use two forms of contraception, and have monthly pregnancy tests.”

This section doesn’t just protect the baby-it protects the woman’s autonomy and right to make informed reproductive choices.

What to do if the label is confusing

Even with better labeling, the information can feel overwhelming. Here’s how to cut through the noise:

  1. Start with the Risk Summary. Ignore the Data section unless you’re a clinician. The summary gives you the bottom line.
  2. Look for percentages. A “2-fold increased risk” sounds scary-until you realize it’s going from 1% to 2%. That’s a 1% absolute increase.
  3. Check for gestational timing. Many drugs are only risky in the first trimester. If you’re in your third trimester, the risk may be minimal.
  4. Use trusted databases. If the label doesn’t help, turn to MotherToBaby or TERIS. These are free, evidence-based services staffed by specialists who answer questions from real patients.
  5. Ask your pharmacist. Pharmacists now spend 5-7 extra minutes per prescription counseling on PLLR labels. They’re trained to explain them.

Common mistakes people make

  • Thinking “no data” means “dangerous.” Often, it just means not enough women took the drug during pregnancy to study it. That’s different from proven harm.
  • Stopping medication without talking to your doctor. Stopping an antidepressant or seizure medication can be more dangerous than continuing it. The risk of uncontrolled depression or seizures is often higher than the drug’s risk.
  • Ignoring the lactation section. Many women assume all drugs are unsafe while breastfeeding. But 90% of medications have low or negligible transfer into milk.
  • Assuming all generic drugs have the same labeling. Generic manufacturers had until 2020 to update labels. Some still have old information. Always check the brand name label.
A registry drone connecting diverse pregnant women to a central AI core with glowing data blossoms and medication safety icons.

What’s changing in 2026?

The FDA is working on visual aids to make PLLR labels easier to read. By 2025, you’ll likely see icons next to drug labels-like a small baby with a red slash for high risk, or a green check for low risk. These are still in draft, but they’re coming.

Also, more data is being collected. Since 2014, pregnancy registries have grown from 5,000 to over 25,000 pregnancies tracked annually. That means better, more diverse data. But there’s still a gap: only 15% of registry participants are Black or Hispanic, even though they make up 30% of U.S. pregnancies. The FDA is pushing for more inclusive enrollment.

By 2026, nearly all prescription drugs in the U.S. will have PLLR-compliant labels. The transition is complete. The challenge now is learning how to use them.

Bottom line: You’re not alone

It’s okay to feel overwhelmed. Even doctors needed training to adapt. But the new system is designed to give you real answers-not oversimplified letters. The goal isn’t to scare you. It’s to empower you.

If you’re pregnant or breastfeeding and taking medication:

  • Don’t stop without talking to your provider.
  • Ask for the latest drug label-either from your pharmacist or online via the FDA’s website.
  • Use MotherToBaby.org or call 1-866-626-6847 for free, personalized advice.
  • Remember: the safest choice isn’t always the one with the least drugs. Sometimes, it’s the one that keeps you healthy.

Are pregnancy drug labels the same worldwide?

No. The U.S. uses the PLLR system, but the European Medicines Agency (EMA) adopted a similar narrative format in 2016. Canada, Australia, and the UK follow similar guidelines. However, some countries still use letter categories or simplified warnings. Always check the label for your country’s regulatory body.

Can I trust the data in the new labels?

Yes, but with context. The data comes from human studies, registries, and pharmacokinetic models-all reviewed by the FDA. But most data comes from observational studies, not randomized trials (which are unethical during pregnancy). That means the labels show associations, not always direct cause. Still, they’re the best available evidence.

What if my drug doesn’t have a PLLR label yet?

By 2026, almost all prescription drugs in the U.S. have updated labels. If yours doesn’t, it may be an older generic or a medication with very limited use. Contact your pharmacist or check the FDA’s online drug database. They can tell you if a newer version is available.

Is it safe to take supplements during pregnancy or breastfeeding?

Supplements aren’t required to have PLLR labeling because they’re regulated as food, not drugs. That’s a major gap. Many herbal products and high-dose vitamins have unknown risks. Always discuss supplements with your provider-even prenatal vitamins. Some contain excessive vitamin A, which can be toxic in pregnancy.

How do I find the latest drug label?

Go to the FDA’s Drugs@FDA website (fda.gov/drugsatfda) and search by brand or generic name. Click on the “Labeling” tab. You can also ask your pharmacist for a printed copy or use the FDA’s free PLLR Navigator mobile app.

Can I use these labels to decide whether to get pregnant?

Yes, and you should. The Reproductive Potential section (8.3) helps you plan. If you’re taking a high-risk medication and considering pregnancy, talk to your doctor at least 3-6 months in advance. Some drugs need to be switched or tapered slowly. Planning reduces risk.

Next steps

If you’re currently pregnant or breastfeeding and taking medication:

  • Find the most recent label for each drug you take.
  • Highlight the Risk Summary and Clinical Considerations.
  • Call MotherToBaby or visit their website for free, personalized guidance.
  • Bring the label to your next appointment. Ask: “Based on this, should I change anything?”

Knowledge is power. The new system doesn’t make decisions for you-but it gives you the tools to make them with confidence.

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