FDA Pregnancy Drug Safety Guidance: How to Read Medication Risks Before, During, and After Pregnancy

Medication decisions during pregnancy rarely fit into a simple “safe” or “unsafe” box. A medicine that is unnecessary for one person may be essential for another. A drug that raises concern in one trimester may carry a different level of concern later in pregnancy. A prescription that should be avoided for one condition may still be considered when the risk of untreated disease is greater than the possible medication risk. This is why FDA pregnancy drug safety guidance has moved away from oversimplified labels and toward a more complete, evidence-based way of explaining medication risks during pregnancy, lactation, and reproductive planning [1].

For years, many patients and even some websites relied on the old FDA pregnancy categories: A, B, C, D, and X. Those categories looked simple, but simplicity was also the problem. The letters could make one medicine appear safer than another even when the quality, amount, or type of evidence was very different. FDA removed those pregnancy letter categories because they were considered confusing and too limited to communicate real-world risk during pregnancy, breastfeeding, and reproductive planning [2].

Today, FDA pregnancy drug labeling uses a more detailed system. Instead of assigning a single letter, prescription drug labels now explain pregnancy risk through structured sections that describe available human data, animal data, clinical considerations, lactation information, and issues for females and males of reproductive potential [1]. This approach is designed to help healthcare providers and patients discuss medication decisions with more context, not less.

This guide explains how FDA pregnancy drug safety guidance works, what happened to the old pregnancy categories, how to understand the Pregnancy and Lactation Labeling Rule, why pregnancy exposure registries matter, and what questions to ask before starting, stopping, or continuing a medicine during pregnancy.

Why medication safety during pregnancy is complicated

Pregnancy changes the way medication decisions should be made. A pregnant patient is not simply a smaller or more delicate version of a nonpregnant patient. Pregnancy can change how the body absorbs, distributes, metabolizes, and clears certain medicines. It can also change the seriousness of untreated medical conditions. At the same time, fetal development is time-sensitive, and certain exposures may matter more during specific windows of pregnancy than at other times.

This is why a medication decision during pregnancy should include both sides of the risk equation. One side is the possible risk of taking the medicine. The other side is the possible risk of not treating the condition. FDA’s consumer guidance recognizes that many pregnant people take medicines for health problems that existed before pregnancy, while others need treatment for conditions such as diabetes, morning sickness, or high blood pressure that can begin or worsen during pregnancy [5].

CDC also emphasizes that avoiding or stopping a medicine during pregnancy can sometimes be more harmful than taking it, depending on the condition and the treatment plan [10]. That point is essential. Pregnancy drug safety is not just about avoiding exposure. It is about making the safest evidence-based decision for the pregnant patient and the developing baby.

The challenge is that pregnancy safety data are often incomplete. Pregnant people have historically been excluded or underrepresented in many clinical trials, which means that information about drug safety during pregnancy may be limited when a product is first approved. FDA noted in 2026 that many pregnant women may benefit from medications, but there is often limited or no human data at the time of approval about how those products affect pregnancy [9]. That gap is one reason FDA continues to emphasize postapproval pregnancy safety studies and pregnancy exposure registries.

What FDA pregnancy drug safety guidance means

FDA pregnancy drug safety guidance refers to the way FDA communicates and updates safety information about prescription drugs and biological products used before pregnancy, during pregnancy, while breastfeeding, and by people of reproductive potential. The central framework is the Pregnancy and Lactation Labeling Rule, commonly called PLLR [1].

The PLLR changed the content and format of pregnancy-related information in prescription drug labeling. Its goal is to help healthcare providers assess benefit versus risk and counsel pregnant patients and nursing mothers who may need medication [1]. Instead of giving a one-letter category, the label now provides a narrative explanation of what is known, what is not known, and what factors may affect clinical decision-making.

Under current FDA labeling, the “Use in Specific Populations” section includes three major areas: Pregnancy, Lactation, and Females and Males of Reproductive Potential [3]. These sections are not just technical labels for regulators. They are meant to support real conversations between healthcare providers and patients.

The Pregnancy subsection may include a risk summary, clinical considerations, data, and pregnancy exposure registry information when a registry is available [1]. The Lactation subsection explains information about using the drug while breastfeeding, including the amount of drug in breast milk when known and possible effects on the breastfed infant [1]. The Females and Males of Reproductive Potential subsection can include information about pregnancy testing, contraception, and infertility when those issues are relevant to the drug [1].

This system is more useful than the old letter categories because it shows the reasoning behind the risk statement. It allows a clinician to consider the patient’s diagnosis, disease severity, trimester, dose, alternative therapies, lactation plans, and the strength of available evidence.

Why the old FDA pregnancy categories were removed

The old FDA pregnancy categories were once widely used. Many patients still search for phrases such as “Category B drugs in pregnancy” or “Category C pregnancy meaning.” However, these categories are no longer the current FDA system for prescription drug pregnancy labeling.

FDA removed the pregnancy letter categories because they were often viewed as confusing and overly simplistic [2]. The letters did not effectively communicate the risk a drug may have during pregnancy and lactation or in females and males of reproductive potential [2]. A single letter could not show whether the evidence came from well-designed human studies, limited case reports, animal studies, pharmacology, or theoretical concern.

For example, two drugs could share the same pregnancy category but have very different evidence behind them. One might have reassuring human data, while another might have only animal data. A letter alone could make those two drugs appear similar when they were not. In other cases, a category could make a medicine seem more dangerous than it actually was for a particular patient whose untreated condition posed a serious risk.

The Federal Register final rule stated that the pregnancy categories A, B, C, D, and X had to be removed from human prescription drug and biological product labeling [4]. The final rule also required labeling to include a summary of pregnancy and lactation risks, a discussion of the data supporting that summary, and relevant information to help healthcare providers make prescribing decisions and counsel patients [4].

This change matters because many online drug lists are still outdated. If a website presents pregnancy safety only as Category A, B, C, D, or X, it may not be using the current FDA labeling framework. That does not automatically mean every statement on the page is wrong, but it does mean the reader should confirm the information using the current drug label and a qualified healthcare professional.

How the Pregnancy and Lactation Labeling Rule works

The Pregnancy and Lactation Labeling Rule was published by FDA in 2014 and became effective in 2015 [1,4]. It changed how pregnancy, lactation, and reproductive potential information appears in prescription drug labeling.

The old label structure included sections such as “Pregnancy,” “Labor and delivery,” and “Nursing mothers.” Under PLLR, the labeling structure was revised. Information about labor and delivery was folded into the Pregnancy subsection, “Nursing mothers” was renamed “Lactation,” and a new subsection was added for Females and Males of Reproductive Potential [1,4].

The Pregnancy subsection is numbered 8.1. The Lactation subsection is numbered 8.2. The Females and Males of Reproductive Potential subsection is numbered 8.3 [3]. These sections appear under “Use in Specific Populations” in prescription drug labeling.

The Pregnancy subsection can include several types of information. It may identify whether a pregnancy exposure registry exists. It may summarize the risk of adverse developmental outcomes. It may include clinical considerations such as disease-associated maternal or fetal risk, dose adjustments during pregnancy or postpartum, maternal adverse reactions, fetal or neonatal adverse reactions, or labor and delivery considerations [4]. It also includes a data section explaining the evidence that supports the risk summary and clinical information [1,4].

The Lactation subsection focuses on breastfeeding. It may discuss whether the drug is present in human milk, whether it may affect the breastfed infant, and whether it may affect milk production [4]. When information is available, it can also include ways to minimize infant exposure or monitor for possible adverse effects [4].

The reproductive potential subsection can include information about pregnancy testing, contraception, and infertility when relevant [1]. This matters because some medications require pregnancy prevention before and during treatment, some may affect fertility, and some may have implications for male reproductive potential as well as female reproductive potential.

What the Risk Summary means

The Risk Summary is one of the most important parts of current FDA pregnancy drug labeling. It is also one of the easiest parts to misunderstand.

A Risk Summary does not mean “this drug is safe” or “this drug is unsafe.” It summarizes available information about the risk of using a drug during pregnancy or lactation. For pregnancy, the Risk Summary may draw from human data, animal data, pharmacologic data, or a combination of sources [4]. The quality and quantity of the evidence can vary widely from one drug to another.

If a drug is not systemically absorbed, the Risk Summary may state that maternal use is not expected to result in fetal exposure, depending on the evidence and labeling requirements [4]. If a drug is systemically absorbed, the Risk Summary should include risk statements based on relevant sources that describe the risk of adverse developmental outcomes [4].

The key is to read the Risk Summary together with the Data and Clinical Considerations sections. A short statement without context can be misleading. A medicine may have limited human data, reassuring animal data, concerning animal data at high exposures, or known risks that must be weighed against the risk of untreated illness. The label is designed to show those distinctions.

Patients should not use the Risk Summary as a do-it-yourself decision tool. Instead, it should support a discussion with a clinician. The right question is not simply, “Is this medicine safe?” A better question is, “What does the label say about known risks, missing data, the risk of untreated disease, possible alternatives, and monitoring for my specific situation?”

Clinical considerations: the part patients should not skip

The Clinical Considerations section is especially important because it connects evidence to real patient care. It may discuss disease-associated maternal or fetal risk, dose adjustments during pregnancy and postpartum, adverse reactions, fetal or neonatal effects, and labor or delivery issues [4].

This is where FDA labeling becomes more practical. For example, a medicine decision may change if the patient’s condition is mild, severe, controlled, uncontrolled, new, chronic, or life-threatening. A medication may be used differently in someone with a long-standing condition than in someone with a temporary symptom. The same drug may require different monitoring during pregnancy or after delivery.

Disease-associated risk is a crucial concept. Some medical conditions can harm the pregnant patient or fetus if they are not treated well. A label that discusses disease-associated risk helps the clinician explain why stopping a medicine may not automatically reduce overall risk. In some situations, the untreated condition may pose a greater danger than the medication.

This section also helps prevent a common mistake: focusing only on fetal risk while ignoring maternal health. The health of the pregnant patient and the health of the fetus are closely connected. Medication decisions should protect both whenever possible.

Lactation labeling and breastfeeding decisions

FDA pregnancy drug safety guidance does not end at delivery. Many patients need medication while breastfeeding, and drug labeling must address lactation when relevant. Under PLLR, the old “Nursing mothers” subsection was renamed “Lactation” [1].

The Lactation subsection may include information about the presence of the drug in human milk, the effects of the drug on the breastfed child, and the effects of the drug on milk production [4]. This is important because breastfeeding decisions involve more than whether a drug enters milk. The dose in milk, infant age, infant health, drug properties, maternal dose, and treatment alternatives may all matter.

A medicine that appears in breast milk is not automatically forbidden. Some medicines may be compatible with breastfeeding under medical supervision, while others may require caution, monitoring, temporary interruption, or avoidance. The label helps clinicians evaluate those possibilities.

Patients should also tell their clinician if they are breastfeeding, planning to breastfeed, pumping, combination feeding, or weaning. A medication plan may be different for a premature newborn, a medically fragile infant, or an older healthy infant. FDA labeling gives the framework, but the clinical decision should be individualized.

Females and males of reproductive potential

The reproductive potential section is one of the most important changes under PLLR because it addresses safety before pregnancy occurs. Many medication risks are not limited to people who are already pregnant. Some drugs may require pregnancy testing before treatment. Some may require contraception during treatment or for a period after stopping treatment. Some may affect fertility.

FDA’s labeling framework includes a subsection for Females and Males of Reproductive Potential when this information is relevant [1,3]. This section can include pregnancy testing, contraception recommendations, and infertility information related to the drug [1].

This matters for people who are trying to conceive, could become pregnant, have a partner who could become pregnant, or are using medications that may affect reproductive planning. It also matters for clinicians who prescribe medications in primary care, dermatology, psychiatry, rheumatology, neurology, oncology, infectious disease, and other fields where treatment may overlap with reproductive age.

A patient does not need to be actively planning pregnancy for this section to matter. Unplanned pregnancies happen, and some medications require planning before conception. If a medication has reproductive implications, the discussion should happen before pregnancy whenever possible.

Pregnancy exposure registries: what they are and why they matter

Pregnancy exposure registries are research studies that collect information about prescription medicines or vaccines used during pregnancy and possible effects on the pregnant person, the developing fetus, and sometimes the newborn after birth [6]. They are one of the major tools used to improve medication safety knowledge after a drug or vaccine is already in use.

FDA explains that pregnancy exposure registries collect information from women who are taking or have taken a certain medicine or received a certain vaccine while pregnant [6]. Some registries also collect information from pregnant women who were not exposed to the medicine or vaccine, which can help provide comparison information [6]. Some registry studies also collect information about newborn babies for a period of time after birth [6].

Pregnancy exposure registries matter because many medication risks cannot be fully understood before approval. A clinical trial may not include enough pregnant participants to identify pregnancy-specific risks. After approval, real-world use can provide additional information. Registries can help healthcare providers and pregnant patients learn more about the safety of medicines and vaccines used during pregnancy [6].

FDA lists ongoing pregnancy exposure registries, but it does not run these registry studies and does not endorse any individual registry listed on its page [7]. The registries are often run by drug companies, researchers, or other organizations [5,7]. This distinction is important. A listing on FDA’s website helps patients and clinicians find registry information, but it is not the same as FDA approval of the registry’s content or conclusions.

Patients who are pregnant and taking a medicine or vaccine can ask their healthcare provider whether a pregnancy exposure registry is available. If a registry is open and enrolling, participation may help improve future safety information for other patients [5,6].

FDA’s 2026 postapproval pregnancy safety studies guidance

In May 2026, FDA issued final guidance titled “Postapproval Pregnancy Safety Studies” [8]. This guidance provides recommendations for sponsors and investigators on how to design studies that assess outcomes among pregnant women exposed to FDA-regulated drug and biological products in the postapproval setting [8]. FDA stated that the final guidance replaced or finalized a draft guidance of the same name issued in 2019 [8].

This guidance is important because it focuses on the evidence gap that often exists after a medicine is approved. FDA noted in its May 2026 announcement that many pregnant women may benefit from medications, but there is often limited or no human data at approval about how these products affect pregnancy [9]. Collecting safety information after approval can help researchers, regulators, clinicians, and patients better understand possible risks to the pregnant patient and developing fetus [9].

The guidance also points to multiple methods for collecting pregnancy safety data. FDA’s announcement describes pregnancy registries, complementary studies that evaluate real-world data, and descriptive studies based on reports from individual cases [9]. The goal is to generate information that can be included in drug labeling and help healthcare providers and patients make informed decisions [9].

This is a major point for readers: FDA pregnancy drug safety guidance is not static. Labels can be updated when new information becomes available. The PLLR framework requires that labels be updated when information becomes outdated [1]. Over time, pregnancy registries, real-world data, claims data, electronic health records, case reports, and other research methods may help improve the quality of the evidence.

Why “safe medication in pregnancy” lists can be misleading

Online lists of “safe medications during pregnancy” are popular because they are easy to read. However, they can also be misleading if they do not explain context. A medicine decision during pregnancy depends on the patient, diagnosis, severity of illness, dose, timing, route of administration, trimester, available evidence, alternatives, and the risk of not treating the condition.

A list may say that a medication is commonly used in pregnancy, but that does not mean it is the right choice for every patient. A list may say that a drug should be avoided, but that does not explain whether it might still be considered in rare or serious circumstances. A list may repeat old FDA pregnancy categories, even though those categories have been removed from current prescription drug labeling [1,2].

FDA also warns consumers not to assume that a product is safe just because it is described as “natural” [5]. This is an important point because pregnancy-related searches often include herbs, supplements, vitamins, teas, and alternative products. Natural products can still have active ingredients, side effects, contamination risks, interactions, or pregnancy-specific concerns.

A better approach is to use online information as a starting point, not the final answer. The most reliable process is to check the current drug label, review FDA or CDC resources, gather your medication list, and talk with a healthcare provider before starting or stopping a medicine [5,10].

Prescription drugs, over-the-counter medicines, supplements, and vitamins

Many people think FDA pregnancy drug safety guidance applies only to prescription drugs, but pregnancy medication decisions often involve over-the-counter medicines, supplements, vitamins, and herbal products too. FDA’s PLLR format specifically applies to prescription drug and biological product labeling under the relevant FDA labeling rules [1,3,4]. However, patients should discuss all medicines and health products with a clinician during pregnancy, not only prescriptions.

CDC advises patients who are pregnant or thinking about getting pregnant to talk with healthcare providers before starting or stopping any medicines and to discuss all medicines they take, including prescriptions, over-the-counter medicines, herbal and dietary supplements, and vitamins [10]. This matters because over-the-counter does not always mean risk-free, and supplements can interact with prescription medicines.

MedlinePlus also notes that even medicines considered safe can cause unwanted side effects or interactions with food, alcohol, or other medicines, and that some medicines may not be safe during pregnancy [11]. The safest approach is to treat every medication decision as part of the full care plan.

Before a prenatal visit, patients can prepare a complete medication list. That list should include prescription medicines, over-the-counter medicines, vitamins, minerals, herbal products, dietary supplements, topical products, inhalers, eye drops, injections, and medicines taken only occasionally. The clinician can then evaluate the full picture rather than one medicine at a time.

How to read a current FDA drug label

A patient does not need to be a regulatory expert to read a drug label, but it helps to know where to look. For prescription drugs, the sections most relevant to pregnancy are usually under “Use in Specific Populations.” The pregnancy information is typically in section 8.1, lactation in section 8.2, and reproductive potential in section 8.3 [3].

When reading section 8.1 Pregnancy, look for whether a pregnancy exposure registry is mentioned. Then read the Risk Summary, Clinical Considerations, and Data sections together. The Risk Summary gives the high-level explanation. Clinical Considerations explain practical issues such as untreated disease risk or monitoring. The Data section explains what evidence supports the label.

When reading section 8.2 Lactation, look for information about human milk, infant effects, and milk production [4]. Do not assume that the presence of a drug in milk automatically means breastfeeding must stop. The clinical decision depends on the medicine, infant, dose, and treatment need.

When reading section 8.3 Females and Males of Reproductive Potential, look for pregnancy testing, contraception, or infertility information [1]. This section can be important even before pregnancy begins.

Patients can ask a clinician or pharmacist to help interpret the label. Drug labels are written for professional use, so some sections may be technical. A pharmacist, obstetrician, maternal-fetal medicine specialist, primary care clinician, or prescribing specialist can help translate the label into a patient-specific decision.

What to ask before starting a medicine during pregnancy

Before starting a medicine during pregnancy, the most useful question is not simply, “Is it safe?” A better question is, “What are the benefits and risks of this medicine compared with the benefits and risks of not treating my condition?” This framing matches the way FDA labeling is intended to support benefit-risk assessment [1].

A patient should ask what condition the medicine treats, how serious the condition is, what could happen if it is not treated, whether non-drug options are appropriate, what pregnancy-specific risks are known, and what evidence supports those risks. The patient should also ask whether the dose, timing, or route matters; whether the medicine has different considerations by trimester; whether monitoring is needed; and whether there is a pregnancy exposure registry.

It is also important to ask whether the medication could affect labor, delivery, newborn monitoring, breastfeeding, contraception, fertility, or future pregnancy planning. FDA labeling includes pregnancy, lactation, and reproductive potential sections because medication decisions often extend across the full reproductive timeline, not just the months of pregnancy [1,3].

Patients should also discuss personal factors. These may include prior pregnancy complications, current medical conditions, kidney or liver disease, allergies, other medicines, mental health needs, and breastfeeding goals. The same label can lead to different decisions for different patients because medicine decisions are individualized.

What to ask before stopping a medicine during pregnancy

Stopping a medicine during pregnancy can feel like the safest choice, but it is not always safe. CDC advises pregnant people or those thinking about pregnancy to talk with healthcare providers before starting or stopping any medicines [10]. This is especially important for medications used to control chronic conditions.

Before stopping a medicine, ask what could happen if the condition becomes uncontrolled. Ask whether stopping suddenly could cause withdrawal, rebound symptoms, relapse, seizure, blood pressure changes, blood sugar changes, infection risk, mental health crisis, or another serious problem. Ask whether a safer alternative exists and whether the switch should happen gradually.

Some medications require careful tapering. Others may need to be continued because the risk of uncontrolled disease is greater than the potential medication risk. In other cases, a clinician may recommend changing the dose, switching to another medicine, increasing monitoring, or stopping the medicine if the benefit no longer justifies the risk.

The key is not to make the decision alone. FDA labels, pregnancy registries, and safety studies are tools for informed decision-making, but they do not replace individualized care.

What if you took a medicine before knowing you were pregnant?

Many people take medicine before they know they are pregnant. FDA notes that some pregnant people take medicines or receive vaccines before finding out they are pregnant [6]. This situation is common and should be handled calmly, quickly, and with medical guidance.

The first step is to identify the exact medicine, dose, dates taken, reason for use, and estimated pregnancy timing. The second step is to contact a healthcare provider. CDC advises patients concerned about medicines taken before they knew they were pregnant to talk with a healthcare provider, noting that some medicines can be harmful during pregnancy while others are unlikely to cause harm [10].

Do not assume the worst based on an online search. Search results can overstate risks, repeat outdated categories, or fail to explain timing. Some medication risks depend heavily on gestational age, dose, duration, and the specific drug. A clinician can help determine whether any additional monitoring, counseling, or follow-up is needed.

If a pregnancy exposure registry is available for the medicine or vaccine, the patient can ask whether participation is appropriate. Sharing information may help improve future knowledge about medication safety during pregnancy [6].

How FDA labeling supports shared decision-making

The strongest use of FDA pregnancy drug safety guidance is shared decision-making. Shared decision-making means the clinician brings medical expertise and evidence, while the patient brings goals, values, symptoms, preferences, and lived experience. The decision is made together.

This matters because pregnancy medication decisions often involve uncertainty. The label may say that human data are limited. It may describe animal findings that are difficult to translate directly to human pregnancy. It may identify possible fetal risk, but it may also explain risk from untreated disease. A patient may value symptom control, fetal risk reduction, breastfeeding, mental health stability, or avoiding hospitalization. These values should be part of the conversation.

FDA’s PLLR framework supports this process by replacing a one-letter category with information that can be discussed. The label can show whether evidence is strong or limited. It can explain what outcomes have been observed. It can identify whether a registry exists. It can include clinical considerations that directly affect patient counseling [1,4].

This is also why current labeling is better for healthcare providers. A clinician can compare risks, explain uncertainty, document reasoning, and update recommendations when new evidence becomes available.

Common myths about FDA pregnancy categories and drug safety

One common myth is that Category B meant a medicine was completely safe in pregnancy. That was never a reliable interpretation. The old categories were broad classifications that did not communicate the quality or detail of the evidence well, which is one reason FDA removed them [2].

Another myth is that if a drug has any pregnancy risk, it should never be used. In reality, some medicines with known or potential risks may still be used when the benefit justifies the risk and safer alternatives are not suitable. The label is meant to support benefit-risk assessment, not automatic yes-or-no decisions [1].

A third myth is that natural products are safer than prescription medicines. FDA cautions consumers not to assume a product is safe just because it is described as natural [5]. Supplements and herbal products may have limited pregnancy data, variable ingredients, contamination concerns, or interactions.

A fourth myth is that breastfeeding always has to stop when the mother needs medication. FDA lactation labeling is designed to explain drug presence in milk, possible infant effects, and milk production effects when known [4]. Some medicines may require caution, but others may be compatible with breastfeeding under medical supervision.

A fifth myth is that FDA labels never change. FDA states that PLLR requires labels to be updated when information becomes outdated [1]. Postapproval studies, registries, case reports, real-world data, and safety surveillance can all contribute to improved labeling over time [8,9].

How healthcare providers use FDA pregnancy drug labels

Healthcare providers use FDA pregnancy drug labels to guide counseling, prescribing, monitoring, and documentation. The label helps them understand whether pregnancy data exist, what outcomes have been reported, whether animal findings raise concern, whether the drug enters human milk, and whether contraception or pregnancy testing is recommended.

A clinician may also use the label to compare treatment options. For example, if two medicines can treat the same condition, the clinician may look at which one has better pregnancy data, which one has a lower risk profile, which one has worked for the patient before, and which one is appropriate for the severity of the condition.

Pharmacists can also play a major role. They can help patients identify drug interactions, review over-the-counter products, interpret label language, and prepare questions for the prescribing clinician. Obstetricians and maternal-fetal medicine specialists can help assess pregnancy-specific risks, while the specialist managing the underlying condition can help assess the risk of changing treatment.

The best decisions often come from coordination. A patient with epilepsy, hypertension, diabetes, autoimmune disease, depression, infection, asthma, or another condition may need input from more than one clinician. FDA labeling provides a common evidence framework for those discussions.

Why postapproval evidence is so important

The approval of a drug is not the end of safety learning. In pregnancy, it is often the beginning of a longer evidence-building process. FDA’s 2026 postapproval pregnancy safety studies guidance reflects the need for better data after drugs and biological products are used in real-world pregnant populations [8,9].

Postapproval pregnancy safety studies can include pregnancy registries, descriptive studies based on individual case reports, and complementary studies using real-world data [9]. These approaches can help identify possible safety signals, describe outcomes, and improve the information available for labeling.

Real-world evidence can be valuable because it reflects how medicines are used outside controlled trials. However, it also requires careful study design. Pregnancy studies must consider timing of exposure, gestational age, outcome definitions, confounding factors, underlying disease, comparator groups, and follow-up. Poorly designed studies can mislead, while well-designed studies can improve clinical counseling.

FDA’s broader work on pregnancy safety study frameworks and registries shows that the agency is paying attention to how evidence is generated, not just how it is displayed in labels [8,9]. For patients, the practical takeaway is that current labels are based on the best available evidence at the time, but evidence can improve.

FAQs

References

[1] FDA. Pregnancy and Lactation Labeling Resources.
https://www.fda.gov/drugs/labeling-information-drug-products/pregnancy-and-lactation-labeling-resources
Brief: Official FDA page explaining the Pregnancy and Lactation Labeling Rule, removal of old pregnancy letter categories, and the Pregnancy, Lactation, and Reproductive Potential label sections.

[2] FDA. Questions and Answers on the Pregnancy and Lactation Labeling Rule.
https://www.fda.gov/drugs/labeling-information-drug-products/questions-and-answers-pregnancy-and-lactation-labeling-rule
Brief: FDA Q&A explaining why the old pregnancy categories were removed and why they were considered confusing and overly simplistic.

[3] FDA. Pregnancy, Lactation, and Reproductive Potential: Labeling for Human Prescription Drug and Biological Products — Content and Format.
https://www.fda.gov/regulatory-information/search-fda-guidance-documents/pregnancy-lactation-and-reproductive-potential-labeling-human-prescription-drug-and-biological
Brief: FDA guidance page describing subsections 8.1 Pregnancy, 8.2 Lactation, and 8.3 Females and Males of Reproductive Potential.

[4] Federal Register. Content and Format of Labeling for Human Prescription Drug and Biological Products; Requirements for Pregnancy and Lactation Labeling.
https://www.federalregister.gov/documents/2014/12/04/2014-28241/content-and-format-of-labeling-for-human-prescription-drug-and-biological-products-requirements-for
Brief: Official final rule describing the PLLR requirements, including risk summaries, clinical considerations, data, lactation information, and removal of pregnancy categories.

[5] FDA. Medicine and Pregnancy.
https://www.fda.gov/consumers/womens-health-topics/medicine-and-pregnancy
Brief: FDA consumer guidance on medicine use during pregnancy, talking with healthcare providers, reporting problems, and volunteering for pregnancy exposure registries.

[6] FDA. Pregnancy Exposure Registries.
https://www.fda.gov/consumers/womens-health-topics/pregnancy-exposure-registries
Brief: FDA explanation of pregnancy exposure registries and how they collect information about medicines or vaccines used during pregnancy.

[7] FDA. List of Pregnancy Exposure Registries.
https://www.fda.gov/consumers/pregnancy-exposure-registries/list-pregnancy-exposure-registries
Brief: FDA list of registry studies, with an important note that FDA does not run or endorse the registries listed.

[8] FDA. Postapproval Pregnancy Safety Studies.
https://www.fda.gov/regulatory-information/search-fda-guidance-documents/postapproval-pregnancy-safety-studies
Brief: FDA’s final guidance page, current as of May 8, 2026, on designing postapproval pregnancy safety studies for drugs and biological products.

[9] FDA. FDA Issues Guidance to Improve Collection of Pregnancy Safety Data for Drugs and Biologics.
https://www.fda.gov/news-events/press-announcements/fda-issues-guidance-improve-collection-pregnancy-safety-data-drugs-and-biologics
Brief: FDA news release announcing the May 8, 2026 final guidance and explaining the need for clearer pregnancy safety data after approval.

[10] CDC. Medicine and Pregnancy: An Overview.
https://www.cdc.gov/medicine-and-pregnancy/about/index.html
Brief: CDC overview explaining that medicine use in pregnancy is common and advising patients to talk with healthcare providers before starting or stopping medicines.

[11] MedlinePlus. Medicines.
https://medlineplus.gov/medicines.html
Brief: Consumer health resource noting that medicines can have risks, side effects, and interactions, and that some medicines may not be safe during pregnancy.