Is Augmentin (amoxicillin-clavulanate) safe to use in pregnant women with a diagnosed bacterial infection?

Augmentin Safety in Pregnancy

Augmentin (amoxicillin-clavulanate) is safe and recommended for treating bacterial infections throughout pregnancy, with the critical exception that it should be avoided in women at risk of preterm delivery due to a documented association with neonatal necrotizing enterocolitis. 1

Safety Classification and Evidence Base

• The American College of Obstetricians and Gynecologists classifies amoxicillin-clavulanate as "Compatible" for use throughout all trimesters, representing the highest level of safety evidence available. 1
• Amoxicillin alone carries FDA Category A designation, while the combination formulation is Category B1—both indicating extensive human data showing no increased risk of congenital malformations, premature births, stillbirths, spontaneous abortions, or low birth weight. 1
• Beta-lactam antibiotics, including penicillins and cephalosporins, have decades of clinical experience documenting their pharmacokinetics in pregnant women and overall fetal safety, making them the most favored agents for susceptible infections during pregnancy. 2, 3

Clinical Indications and Recommendations

• The American College of Gastroenterology recommends amoxicillin-clavulanate as a first-line antibiotic during pregnancy when beta-lactam coverage is appropriate for the suspected or confirmed pathogen. 1
• The American Gastroenterological Association recommends it specifically for treating inflammatory bowel disease complications during pregnancy, including perianal Crohn's disease and intra-abdominal abscesses from fistulizing disease. 1
• For urinary tract infections in pregnancy, the Infectious Diseases Society of America recommends amoxicillin 500 mg IV/PO every 8 hours as a safe and effective option. 1
• Penicillins remain the first-line antibiotic treatment during pregnancy, with the exception of cases involving maternal penicillin allergy. 4

Critical Contraindication: Preterm Delivery Risk

The American College of Obstetricians and Gynecologists specifically recommends avoiding amoxicillin-clavulanate in women at risk of preterm delivery due to a documented, though very low, risk of necrotizing enterocolitis in the fetus. 1

• The Centers for Disease Control and Prevention recommend considering alternative antibiotics, such as amoxicillin alone (without clavulanate), in women with threatened preterm labor rather than the combination formulation. 1
• This represents the single most important clinical pitfall to avoid when prescribing Augmentin in pregnancy—always assess preterm delivery risk before prescribing. 1

Comparison to Alternative Antibiotics

• The American Academy of Pediatrics recommends amoxicillin-clavulanate over azithromycin due to its superior safety classification, making it the preferred choice when both would provide adequate coverage. 1
• Unlike tetracyclines (contraindicated after the fifth week of pregnancy) and fluoroquinolones (contraindicated as a precautionary measure), amoxicillin-clavulanate has no known teratogenic effects according to the FDA. 1, 4
• Cephalosporins represent another first-line option during pregnancy, with more commonly used cephalosporins given priority. 4

Breastfeeding Compatibility

• The Academy of Breastfeeding Medicine classifies amoxicillin as compatible with breastfeeding, with penicillins present in breast milk only at low concentrations. 1
• The World Health Organization recommends monitoring breastfed infants for gastrointestinal effects due to potential alteration of intestinal flora, though serious adverse events are rare. 1

Pharmacokinetic Considerations

• Physiologic changes in pregnancy—including increased glomerular filtration rate, increased total body volume, and enhanced cardiac output—may lead to pharmacokinetic alterations in antibiotics that require dose adjustment or careful monitoring. 5
• Despite these changes, beta-lactams maintain their safety profile and effectiveness when dosed appropriately. 5

Clinical Decision Algorithm

1. Confirm bacterial infection requiring antibiotic treatment (untreated infections carry significant morbidity including low birth weight, preterm birth, and spontaneous abortion). 5
2. Assess preterm delivery risk factors (history of preterm birth, current threatened preterm labor, cervical insufficiency). 1
3. If preterm delivery risk is present: Use amoxicillin alone or alternative beta-lactam; avoid amoxicillin-clavulanate. 1
4. If no preterm delivery risk: Amoxicillin-clavulanate is safe and appropriate throughout all trimesters. 1
5. If penicillin allergy: Consider cephalosporins (first-line alternative) or other pregnancy-compatible antibiotics based on infection type. 4, 2

Common Pitfalls to Avoid

• Never prescribe amoxicillin-clavulanate to women with threatened preterm labor or significant preterm delivery risk factors—this is the most critical error to avoid. 1
• Do not withhold necessary antibiotic treatment due to pregnancy concerns when appropriate agents are available—untreated infections pose greater risks to both mother and fetus than properly selected antibiotics. 4, 5
• Avoid aminoglycosides (nephrotoxicity and ototoxicity), tetracyclines (contraindicated after week 5), and fluoroquinolones (contraindicated as precaution) when beta-lactams would be effective. 4, 2