Phase 1 Study of the Pharmacokinetics of Amoxicillin in Pregnancy

Inclusion Criteria: 1. Pregnant, engaged in prenatal care with a medical provider (at least one visit) 2. Estimated gestational age 24-34 weeks 3. Able to provide informed consent 4. English speaking Exclusion Criteria: 1. Receipt of amoxicillin within the past 7 days. (Routine GBS prophylaxis with ampicillin or other antibiotic and routine surgical prophylaxis prior to cesarean with cephalexin and azithromycin 500 mg IV is allowed). 2. Known hypersensitivity or intolerance of amoxicillin, penicillin, other beta lactam or cephalosporin antibiotics. 3. Known renal impairment (serum creatinine ≥1.2 mg/dL). 4. Active concomitant medications known to interact with amoxicillin: allopurinol, methotrexate, mycophenolate, immune checkpoint inhibitors (ie. pembrolizumab), tetracyclines (ie. doxycycline), vitamin K antagonists (ie. warfarin), aminoglycosides (ie. gentamicin).