Birth Defects from Drugs

Medication for Pregnant WomanToday there is generally widespread public awareness that using illegal drugs and alcohol during pregnancy can cause serious developmental birth defects. However, the use of certain prescription drugs during pregnancy can cause birth defects. Below are a list of prescription medications linked to birth defects.

Serotonin Reuptake Inhibitors 

Selective serotonin reuptake inhibitors (SSRIs) are some of the most widely utilized drugs in the field of mental health. Millions of people take SSRIs for the treatment of depression and anxiety. Until fairly recently SSRIs were considered safe during pregnancy.

However, some studies suggest certain drugs in the SSRI category during pregnancy created a risk of newborn hypertension; spina bifida, heart defects, and other birth defects. The SSRI drugs that cause these problems include Zoloft, Lexapro, Prozac, Paxil, Symbax, Fluvoxamine.

The science on how these drugs cause birth defects and other complications is still evolving. But the list of suspected complications from SSRIs includes spontaneous abortion and congenital malformations in multiple organ systems. These complications include anencephaly, pulmonary defects, respiratory defects, cardiac defects, craniosynostosis, nervous system defects and gastrointestinal defects.

The opinion that these drugs cause birth defects is far from unanimous. Many doctors and certainly the pharmaceutical companies disagree that SSRI drugs cause birth defects.  They argue that the science is still unclear, and that the data is skewed because women who take SSRIs are statistically older - which increases many risks - and are more likely to smoke, take other medications, and struggle with obesity. They also argue that depression alone is a risk factor.

The SSRI debate underscores the difficulty in linking drugs during pregnancy and birth defects, especially when the birth defect occurs after first-trimester exposure to the medication, In these cases, it is sometimes clear if the defect was caused by drug exposure or other factors.  This is particularly complicated with multifactorial defects that are known to have inherited genetic susceptibility.


Benzodiazepines are psychoactive drugs that have been in use since the 1950s. Some examples of benzodiazepines include Xanax (alprazolam), Valium (diazepam), Klonopin (clonazepam), Ativan (lorazepam), and Restoril (temazepam).

Benzodiazepines work by boosting the effectiveness of certain chemical electrical activities within the brain that trigger feelings of calm. Benzodiazepines are widely prescribed for the treatment of various mental health conditions such as anxiety and insomnia. They are also used to control seizures in people with epilepsy or cerebral palsy. The use of benzodiazepines during pregnancy has been linked to developmental birth defects involving lack of muscle control, cardiac and respiratory problems.

Some believe the absolute risk of these defects is still relatively low, and the benefits of treating anxiety or sleep disorders with benzodiazepines may outweigh the risks in some cases. It is important for women who are pregnant or planning to become pregnant to talk to their doctor about any medications they are taking, including benzodiazepines. In some cases, it may be possible to switch to a different medication or to reduce the dose of the medication to lower the risk of birth defects.


Teratogens are substances or factors that can cause congenital anomalies or birth defects in babies when they are exposed to them during pregnancy. These anomalies are structural or functional abnormalities that occur in the developing fetus.

Isotretinoin, which is a medication derived from retinoic acid, has been found to cause congenital anomalies in a significant percentage of cases when pregnant individuals are exposed to it. Isotretinoin is the active ingredient in this Accutane.

Older studies conducted before 2006 suggested that this medication led to congenital anomalies in 21-52% of cases when taken during pregnancy. More recent studies have shown lower rates of congenital anomalies associated with isotretinoin use during pregnancy.   Still, Accutane is high on the list of drugs that cause birth defects. Numerous studies demonstrate the drug causes birth defects and stillbirth if used during pregnancy.


Most first-generation antibiotics are completely safe for use during pregnancy. These include well-known drugs such as amoxicillin, penicillin, ampicillin, and clindamycin. However, recent studies have established a potential link between a particular group of advanced antibiotics and certain developmental birth defects including cleft lip, heart defects, and a skull malformation called anencephaly. The specific antibiotics linked to these birth defects are listed below:

  • Nitrofurantoin: a newer type of antibiotic that is often used to treat chronic or difficult urinary tract infections. The drug is also used for the treatment of bladder inflammation.
  • Sulfonamides: sulfonamides are one of the earliest forms of antibiotics. Known as bacteriostatic antibiotics they contain chemicals from the sulfonamide group. They work by preventing bacteria cells from synthesizing folic acid which they need to grow and multiply. Popular drugs in this group include Gantrisin, Bactrim (Septra), Sulfadiazine, and Zonegran.
  • Tetracyclines: tetracyclines are broad-spectrum polyketide antibiotics that are particularly effective against certain types of bacteria. Use of tetracyclines has decreased in recent years because of problems with resistance. These antibiotics are primarily used for the treatment of acne rosacea and certain sexually transmitted diseases. Popular brand name drugs of this type include Solodyn, Doryx, Vibramycin, Oracea, and Monodox.
Fluconazole / Diflucan

Fluconazole (brand name Diflucan) is a very popular antifungal medication that has been in use since the 1990s. Fluconazole is usually prescribed for the treatment of yeast infections in women and other types of fungal infections. When used during pregnancy fluconazole can significantly increase the risk of having a miscarriage.


NSAIDs (non-steroidal anti-inflammatory drugs) include many of the most widely used over-the-counter pain fever-reducing medications in the world. Millions of people used NSAIDs regularly. NSAIDs include any ibuprofen-based pain relief drug. The most popular over the counter NSAIDs include Tylenol, Motrin, Aleve, and Excedrin.

Prescription-strength NSAIDs include Diclofenac, Lodine, and Meloxicam. Some studies have shown that NSAIDs present a small risk of neural tube and other birth defects. Although these risks are very small, women who are pregnant or planning to become pregnant should probably use alternative medications such as Tylenol.   (We are also seeing Tylenol autism lawsuits in 2023.)

Are we sure NSAIDs cause birth defects?  No. While there is conflicting evidence regarding the risk of birth defects associated with NSAID use during pregnancy, some studies have suggested a potential link. One large study found an association between the use of NSAIDs during the first trimester of pregnancy and an increased risk of some types of birth defects, including heart defects, neural tube defects, and oral clefts. However, other studies have not found a significant association between NSAID use during pregnancy and birth defects.


Anticonvulsants are drugs are used to help prevent or control various types of seizures. Research has shown that a handful of anti-seizure medications are linked to increased rates of certain birth defects such as organ abnormalities, cleft lips, and developmental delays. The particular anticonvulsant drugs linked with this risk include Tegretol, Depakote, Lamictal, and Dilantin. Unfortunately controlling seizures in pregnant women is also important to the health of the baby because certain types of seizures are known to trigger miscarriages.

Research has shown that certain anticonvulsants, such as valproic acid and carbamazepine, can increase the risk of birth defects when taken during pregnancy. One study found that valproic acid (Depakene, Depakote, and Stavzor) use during the first trimester of pregnancy was associated with a 10% risk of major congenital malformations, compared to a 2-3% risk in the general population. Another study found that carbamazepine use during pregnancy was associated with an increased risk of neural tube defects. More research is needed on much of this.  But the concern is real. 

Because the risks associated with anticonvulsant use during pregnancy can be serious, it is important for women who are taking these medications and who are planning to become pregnant to discuss their options with their healthcare provider. In some cases, it may be possible to switch to a different medication or to adjust the dosage to minimize the risks to the fetus.

Additional Information About Drugs & Pregnancy This is not an exhaustive list of medications that can cause birth defects.  For more detailed information about birth defects from drugs, including the research and studies behind various safety warnings, visit the Centers for Disease Control's web page on safe medication use during pregnancy. Finally, Internet research is great. But always consult with your doctor on what is best for you and your condition.

Is Marijuana Safe During Pregnancy?

Marijuana is not considered safe during pregnancy.  This is less about birth defects - although that too is a concern - than it is about the child's health.  But there is so much talk about marijuana being safe we want to address it.  Several studies - here is the most recent - and medical organizations, including the American College of Obstetricians and Gynecologists (ACOG), advise against the use of marijuana during pregnancy.

Here are some reasons why marijuana is not safe during pregnancy:

  1. Developmental Risks: The active compounds in marijuana, including THC, can cross the placenta and reach the developing fetus. This can potentially affect the baby's brain development and lead to long-term cognitive and behavioral problems.

  2. Low Birth Weight: Using marijuana during pregnancy has been associated with an increased risk of having a baby with low birth weight, which can increase the risk of health problems for the infant.

  3. Preterm Birth: Some studies suggest that marijuana use during pregnancy may increase the risk of preterm birth, which can also lead to health complications for the baby.

  4. Cognitive and Behavioral Issues: Children exposed to marijuana in the womb may be at a higher risk of cognitive and behavioral problems, including issues with attention, memory, and impulsivity.

  5. Stillbirth: There is some evidence to suggest that marijuana use during pregnancy may be linked to an increased risk of stillbirth.

  6. Neonatal Withdrawal: Babies exposed to marijuana in utero can experience withdrawal symptoms after birth, similar to what is seen in babies exposed to other drugs.