What Prescription Medications are Known to Cause Birth Defects?

prescription meds and birth defectsCertain medications (prescription or over-the-counter), are known to lead to birth defects if they are taken during pregnancy. While all prescription drugs come with warnings, these drugs cannot be tested on pregnant women in a clinically controlled trial where one group takes a placebo and the other group takes the drug in question because it is unethical to test drugs on pregnant woman. Any drug known to cause a birth defect is referred to as a “teratogen.” These medications are substances that interfere with the normal development of a fetus, and often do their damage during the first trimester of pregnancy – in some cases, they can cause defects and health conditions well into the second and third trimester.  The question of whether these drugs cause birth defects is found out after the fact in retrospective studies where the doctors look to see if groups of women who have taken the drug in question have children with birth defects that is greater than that expected in the population as a whole.

Risk Factors for Birth Defects

Science cannot always predict which baby will be born with a defect, or which baby will be born healthy. Also, research cannot identify which fetuses will be affected by teratogenic drug use and which will not. The potential for harm will depend on a range of factors that include:

  • The type of medication
  • The dosage of that medication
  • How often the mother takes the mediation
  • The stage of fetal development, at the time when the drug is taken
  • The response of the fetus to the drug
  • Maternal diet, illness, and other factors

Birth Defects Can Also Occur, Regardless of Drug Use

It is important to note that medications are not the only reason that a baby could be born with a defect. The risk for defects will vary, and a woman who avoids medications during pregnancy could still have a child born with a defect.

What Teratogenic Drugs are Known to Cause Defects?

There are known teratogenic drugs on the market that can cause birth defects, especially if they are taken during the first trimester. These medications are often avoided by obstetricians, but in some cases, a pregnant woman may need to take these medications – because stopping the medication carries a greater risk to the mother than the fetus’ potential for defect.

These drugs include:

  • ACE Inhibitors (Angiotensin Converting Enzymes)
  • Angiotensin II Antagonists
  • Isotretinoin (Acne Medication)
  • Alcohol
  • Cocaine
  • Vitamin A (in high doses)
  • Lithium
  • Male Hormones
  • Antibiotics (only certain varieties)
  • Anticonvulsant Medications
  • Cancer-Fighting Medications
  • Rheumatic Medications
  • Thyroid Medications
  • Thalidomide
  • Blood Thinning Medications (Warfarin)
  • Hormone Diethylstilbestrol (DES)
  • Certain SSRI’s (anti depressants)

The Classification System

The FDA has pregnancy categories. These categories are assigned based on the potential for a drug to cause birth defects and include:

  • Category A – These well-studied medications did not demonstrate any risk to the fetus when used in the first trimester. Some drugs in this category include folic acid, magnesium sulfate, and levothyroxine.
  • Category B – These have animal reproduction studies that failed to demonstrate a risk to the fetus, and there are no adequate well-controlled substance studies in pregnant women. These medications include metformin, hydrochlorothiazide, amoxicillin, etc.
  • Category C – Studies have shown adverse effects (among animals) on the fetus, and there are no studies in humans. The potential benefits of use may warrant the use, despite the potential risks. These medications include tramadol, gabapentin, trazodone and prednisone.
  • Category D – These have positive evidence of human fetal risk and adverse reactions. In some cases, they may still be prescribed, if the benefits outweigh the risks. These can include medications like alprazolam, losartan, and lorazepam.
  • Category X– These medications should never be taken during pregnancy, and have severe risks to the fetus. They include atorvastatin, warfarin, and methotrexate.
  • Category N – These have not been classified and include things like aspirin, oxycodone, acetaminophen and diazepam.

Did Your Medication Lead to Birth Defects?

If your physician prescribed a medication knowing that there were significant risks to your fetus, but failed to inform you of such risks, you may have a medical malpractice claim against that physician. Contact the attorneys at Carey, Danis & Lowe Attorneys at Law today to explore your options. Schedule a free consultation at 877-678-3400 or fill out our online contact form with your legal questions.