Medication Birth Defects

When a pregnancy is affected by a medication-related birth defect, families often face both immediate medical questions and deeper concerns about what happened and why. Understanding how certain medications can affect fetal development helps parents make informed decisions, work with their healthcare teams, and find the support they need during a difficult time.

Medication-induced birth defects, sometimes called teratogenic effects, occur when a drug taken during pregnancy interferes with the normal development of a baby. While most medications are safe to use, a small number are known to increase the risk of structural or functional abnormalities, particularly when taken during critical windows of fetal growth. Learning which medications carry risk, when that risk is highest, and what steps can reduce harm is essential for anyone planning a pregnancy or already expecting.

At nybirthinjury.com, we provide trusted, medically accurate information to help families understand birth injuries and related conditions, connect with qualified medical resources, and navigate care with confidence.

What Are Medication Birth Defects?

Medication birth defects are congenital abnormalities that develop when a fetus is exposed to certain drugs during pregnancy. These defects can affect physical structure, organ function, or long-term development, depending on the medication involved and the timing of exposure.

A medication that causes birth defects is called a teratogen. Teratogens interfere with the normal process of cell division, tissue formation, and organ development. The result can range from minor abnormalities to serious, life-altering conditions.

Not every baby exposed to a teratogenic medication will develop a birth defect. Risk depends on several factors, including the specific drug, the dose, how long it was taken, and the stage of pregnancy when the exposure occurred. Genetic factors and maternal health also play a role.

The most vulnerable period is the first trimester, particularly between weeks three and eight of pregnancy, when the baby’s major organs and body systems are forming. This is called organogenesis. During this time, even brief exposure to certain medications can have lasting effects.

Common Medications That Cause Birth Defects

Several categories of medications are well-established as teratogens. These drugs are known to increase the risk of specific types of birth defects when used during pregnancy.

Anti-Seizure Medications

Anti-epileptic drugs, also called anticonvulsants, are among the most common teratogens. Medications like valproic acid (Depakote), phenytoin (Dilantin), carbamazepine (Tegretol), and primidone are associated with increased risk of neural tube defects, craniofacial abnormalities, heart malformations, and developmental delays.

Valproic acid is particularly concerning. It has been linked to spina bifida, cleft palate, and cognitive impairments. The risk may increase when multiple anti-seizure drugs are used together or when higher doses are prescribed.

Women with epilepsy face a difficult decision. Uncontrolled seizures during pregnancy also pose risks to both mother and baby. Working closely with a neurologist and obstetrician to find the safest medication at the lowest effective dose is critical.

Isotretinoin

Isotretinoin, sold under the brand name Accutane, is used to treat severe acne. It is one of the most potent teratogens known. Exposure during pregnancy can cause severe cranial, brain, heart, and facial deformities.

Because the risks are so high, isotretinoin is available only through a restricted program that requires pregnancy testing, counseling, and contraception use. Women must stop taking isotretinoin well before trying to conceive.

Thalidomide

Thalidomide was widely prescribed in the 1950s and 1960s as a treatment for morning sickness. It caused thousands of babies to be born with severe limb reduction defects, missing or shortened arms and legs, and abnormalities of the ears and eyes.

Though thalidomide is no longer used for morning sickness, it is still prescribed for certain cancers and immune conditions. Strict safety protocols are required, and the drug is contraindicated in pregnancy.

Selective Serotonin Reuptake Inhibitors

SSRIs are commonly prescribed antidepressants. Most SSRIs are considered relatively safe during pregnancy, but paroxetine (Paxil) has been linked to an increased risk of heart defects, particularly when taken during the first trimester.

Other SSRIs may carry smaller risks. The decision to continue or stop an SSRI during pregnancy should be made carefully, balancing the mother’s mental health needs with potential risks to the baby.

Nonsteroidal Anti-Inflammatory Drugs

NSAIDs like ibuprofen and naproxen are generally safe in early pregnancy, but their use in the third trimester can cause serious complications. These include premature closure of the ductus arteriosus, a blood vessel that is essential for fetal circulation, as well as kidney problems in the baby.

Acetaminophen (Tylenol) is usually recommended as a safer alternative for pain relief during pregnancy.

Diethylstilbestrol

DES was a synthetic estrogen prescribed to pregnant women between the 1940s and 1970s to prevent miscarriage. It was later found to cause reproductive tract abnormalities and increase the risk of a rare form of vaginal cancer in daughters exposed in utero.

Though DES is no longer prescribed during pregnancy, its legacy highlights the importance of long-term monitoring and research into medication safety.

Opioids and Prescription Painkillers

Opioid use during pregnancy has been associated with congenital heart defects, neural tube defects, and neonatal abstinence syndrome, a condition in which newborns experience withdrawal symptoms after birth.

Pregnant women who are dependent on opioids should not stop taking them abruptly, as withdrawal can also harm the baby. Medically supervised treatment, including methadone or buprenorphine, is often the safest approach.

How Common Are Medication-Related Birth Defects?

Birth defects affect about 1 in 33 babies born in the United States each year. While most birth defects have unknown causes, medication exposure is one of the few clearly preventable risk factors.

Studies show that up to 35 percent of women who give birth to babies with defects report taking medications during pregnancy, compared to 17 percent of those whose babies are unaffected. This does not mean the medications always caused the defect, but it does suggest a meaningful association in some cases.

Many women take medications during pregnancy, often before they know they are pregnant. This makes early counseling and careful medication management essential for reducing risk.

Who Is at Higher Risk?

Several factors influence whether a medication will cause harm during pregnancy:

The specific drug matters most. Some medications are highly teratogenic, while others carry little to no known risk.

Timing is critical. The first trimester is the period of highest vulnerability, but some drugs can cause harm later in pregnancy as well.

Dose and duration also matter. Higher doses and prolonged use generally increase risk.

Maternal health conditions, including diabetes, epilepsy, and autoimmune diseases, may require medications that carry some risk. In these cases, untreated illness may pose a greater danger than the medication itself.

Genetics can affect how a mother or baby metabolizes a drug, which may influence the likelihood of harm.

Environmental and lifestyle factors, such as smoking, alcohol use, and nutrition, can interact with medications and increase overall risk.

Preventing Medication-Related Birth Defects

Prevention begins with awareness and planning. Women who are pregnant or planning to conceive should talk with their healthcare provider about every medication they take, including prescriptions, over-the-counter drugs, and supplements.

Preconception Counseling

Ideally, medication risks should be discussed before pregnancy begins. A doctor can help identify safer alternatives, adjust doses, or discontinue medications that are not essential.

For women with chronic conditions like epilepsy, hypertension, or depression, stopping treatment may not be an option. In these cases, the goal is to find the safest medication and lowest effective dose.

Folic Acid Supplementation

Taking 400 micrograms of folic acid daily, starting before conception and continuing through the first trimester, significantly reduces the risk of neural tube defects. This is especially important for women taking anti-seizure medications, which can interfere with folic acid metabolism.

Medication Review Throughout Pregnancy

Medication needs can change as pregnancy progresses. Regular reviews with an obstetrician and pharmacist help ensure that every drug taken is necessary and as safe as possible.

Avoid Self-Medication

Pregnant women should not start or stop any medication without consulting a healthcare provider. Even over-the-counter drugs and herbal supplements can carry risks.

Diagnosing Birth Defects Related to Medication Exposure

When there is concern about medication exposure during pregnancy, several tests can help identify potential birth defects before delivery:

• Prenatal ultrasound is the most common screening tool. It can detect structural abnormalities such as heart defects, limb malformations, and neural tube defects.
• Maternal serum screening measures proteins and hormones in the mother’s blood that may indicate increased risk of certain conditions.
• Genetic testing, including amniocentesis or chorionic villus sampling, can provide more detailed information if a serious defect is suspected.

Early detection allows families to prepare emotionally, gather information, and plan for specialized care at delivery if needed.

Medical Care and Treatment

The type and severity of the birth defect determine what medical care is needed. Some defects are immediately visible at birth and require urgent surgery or intervention. Others may not become apparent until later in infancy or childhood.

Babies born with heart defects may need surgery in the first days or weeks of life. Those with neural tube defects often require neurosurgical procedures and long-term rehabilitation.

Craniofacial abnormalities may involve reconstructive surgery, speech therapy, and dental care over many years.

Developmental delays and cognitive impairments may require early intervention services, special education, and ongoing support.

Many birth defects are managed by multidisciplinary teams that include neonatologists, pediatric surgeons, neurologists, geneticists, therapists, and social workers.

Where to Find Specialized Care in New York

New York is home to several medical centers with expertise in high-risk obstetrics, prenatal diagnosis, and the treatment of birth defects.

Mount Sinai Hospital, NYU Langone Health, Columbia University Irving Medical Center, and Albany Medical Center all offer specialized perinatal services, genetic counseling, and coordinated care for complex cases.

These centers provide access to maternal-fetal medicine specialists who can manage pregnancies affected by medication exposure and help families understand their options.

Support and Resources for Families

Families affected by medication-related birth defects often benefit from a combination of medical care, emotional support, and practical assistance.

The New York State Department of Health offers care coordination, early intervention programs, and access to support groups for families of children with special healthcare needs.

The Centers for Disease Control and Prevention provides educational resources on birth defects, prevention strategies, and ongoing research.

Local perinatal centers and children’s hospitals often have social workers and family navigators who can help connect families with services, financial assistance, and peer support networks.

Support groups, both in-person and online, allow parents to share experiences, ask questions, and find community with others facing similar challenges.

Current Research and Advances

Research into medication safety during pregnancy continues to evolve. Scientists are working to better understand which drugs pose risks, how those risks can be minimized, and how to predict individual susceptibility.

Recent advances include the development of artificial intelligence tools that map connections between thousands of medications and specific birth defects. One example is ReproTox-KG, a knowledge graph created by researchers at Mount Sinai that helps identify drug risks more quickly and accurately.

Pharmacoepidemiologic studies track real-world medication use and outcomes across large populations, helping to clarify which drugs are safe and which require caution.

Despite these efforts, the majority of medications prescribed during pregnancy still have undetermined teratogenic risk in humans. More research, better surveillance systems, and improved reporting are needed to protect future generations.

Moving Forward with Knowledge and Care

No parent expects to face the possibility of a medication-related birth defect. When it happens, the emotions can be overwhelming. Guilt, confusion, anger, and fear are all normal responses.

What matters most is getting accurate information, accessing quality medical care, and finding support. Birth defects caused by medications are often complex, but many children go on to live full, meaningful lives with the right interventions and resources.

Understanding the risks, asking questions, and working closely with healthcare providers can make a significant difference. Families are not alone in this, and help is available.