What medications and procedures should be avoided during pregnancy?

Medications and Procedures to Avoid During Pregnancy

During pregnancy, women should avoid medications that are known to cause fetal harm, including ACE inhibitors, angiotensin receptor blockers, statins, tetracyclines, and fluoroquinolones, as these can cause serious birth defects, fetal renal dysplasia, and other complications.

Medications to Avoid

Cardiovascular Medications

• ACE inhibitors and angiotensin receptor blockers must be discontinued before conception or immediately upon pregnancy confirmation, as they can cause fetal renal dysplasia, oligohydramnios, pulmonary hypoplasia, and intrauterine growth restriction 1, 2
• Statins should be avoided during pregnancy due to potential teratogenic effects 2
• Atenolol should be avoided as it is associated with lower birth weight in infants 2
• Warfarin is contraindicated during pregnancy due to risk of fetal malformations 3
• Diuretics should generally be avoided during pregnancy as they may reduce uteroplacental perfusion 2

Antibiotics and Anti-infectives

• Tetracyclines should be avoided after the fifth week of pregnancy as they can affect bone and tooth development in the fetus 4, 5
• Fluoroquinolones should be avoided during pregnancy due to potential cartilage damage in the developing fetus 6, 5
• Aminoglycosides should be used with extreme caution due to risk of nephrotoxicity and ototoxicity in the fetus 5, 4
• Sulfonamides should be avoided near term due to risk of neonatal hyperbilirubinemia 6

Pain Medications and NSAIDs

• NSAIDs like ibuprofen should be avoided after 20 weeks of pregnancy due to risk of premature closure of the fetal ductus arteriosus and oligohydramnios 7
• NSAIDs at around 30 weeks gestation can cause premature closure of the fetal ductus arteriosus 7
• Paracetamol (acetaminophen) should be used at the lowest effective dose for the shortest possible time, as recent research suggests potential risks to fetal development 8

Other Medications

• Isotretinoin for acne is absolutely contraindicated due to high risk of miscarriage and severe birth defects 2
• Oral antidiabetic agents (except metformin) should be discontinued and replaced with insulin 2
• Miltefosine (used for leishmaniasis) should be avoided during pregnancy 2
• Azoles (antifungal medications) are typically not recommended during pregnancy 2

Medical Procedures to Avoid

Imaging Studies

• X-rays, especially abdominal X-rays, should be avoided when possible, particularly in the first trimester 2
• CT scans of the abdomen and pelvis should be avoided unless absolutely necessary 2

Other Procedures

• Elective surgeries should be postponed until after delivery 2
• Invasive procedures should be limited to those that are medically necessary 2

Safe Alternatives During Pregnancy

Cardiovascular Medications

• Methyldopa, long-acting nifedipine, and labetalol are considered safe and effective for hypertension during pregnancy 1, 2
• Target blood pressure should be 110-135/85 mmHg to reduce risk of maternal hypertension while minimizing impaired fetal growth 2, 1

Antibiotics

• Penicillins and cephalosporins have excellent safety profiles and are first-line antibiotics during pregnancy 6, 4
• Erythromycin is generally considered safe during pregnancy 5
• Nitrofurantoin is generally safe but should be avoided near term 6

Pain Management

• Acetaminophen at recommended doses is generally considered safe but should be used at the lowest effective dose for the shortest duration 9, 8

Diabetes Management

• Insulin is the preferred treatment for diabetes during pregnancy 2
• Metformin may be continued in the preconception period but insulin is preferred during pregnancy 2
• Low-dose aspirin (100-150 mg/day) starting at 12-16 weeks of gestation is recommended for women with diabetes to reduce preeclampsia risk 2

Special Considerations

First Trimester Concerns

• The first trimester (especially weeks 3-8) is the most critical period for organogenesis, when the fetus is most vulnerable to teratogenic effects 2
• Medication exposure during this period poses the highest risk of structural birth defects 5

Later Pregnancy Concerns

• Some medications that are safe in early pregnancy may pose risks in the third trimester (e.g., NSAIDs) 7
• Medications taken near delivery may affect labor or cause neonatal complications 7

Common Pitfalls to Avoid

• Never assume a medication is safe in pregnancy without checking its pregnancy category or recent safety data 9
• Do not continue medications from before pregnancy without reviewing their safety profile 1
• Avoid abrupt discontinuation of essential medications without establishing safe alternatives 2
• Remember that untreated maternal conditions (like severe hypertension, infections, or uncontrolled diabetes) can pose greater risks to the fetus than appropriate medication use 2

Consultation Recommendations

• All medication use during pregnancy should be discussed with an obstetrician 2
• Women with chronic conditions should receive preconception counseling about medication management 2
• For women requiring treatment for chronic conditions, medication regimens should be optimized before conception when possible 1