What is the recommended treatment for chlamydia (Chlamydia trachomatis) in a pregnant patient?

Treatment of Chlamydia in Pregnancy

For pregnant patients with chlamydia infection, azithromycin 1 g orally in a single dose is the recommended first-line treatment due to its superior efficacy, safety profile, and excellent compliance. 1

Recommended Treatment Options

First-Line Regimens

• Azithromycin 1 g orally in a single dose - This is now the preferred treatment due to clinical experience and studies demonstrating safety and effectiveness during pregnancy 1
• Amoxicillin 500 mg orally three times a day for 7 days - An effective alternative with fewer gastrointestinal side effects than erythromycin 1

Alternative Regimens (if first-line options cannot be used)

• Erythromycin base 500 mg orally four times a day for 7 days 1
• Erythromycin base 250 mg orally four times a day for 14 days 1
• Erythromycin ethylsuccinate 800 mg orally four times a day for 7 days 1
• Erythromycin ethylsuccinate 400 mg orally four times a day for 14 days 1

Rationale for Treatment Selection

Efficacy Considerations

• Azithromycin has demonstrated similar or superior efficacy compared to other regimens:
  • One study showed only 5% treatment failure with azithromycin compared to 20% with amoxicillin 2
  • Another study found significantly fewer treatment failures with azithromycin (6.2%) compared to erythromycin (27.7%) 3

Tolerability and Compliance

• Azithromycin has significantly better tolerability than erythromycin:
  • Gastrointestinal side effects were reported in only 19.4% of patients taking azithromycin versus 65.5% of those taking erythromycin 3
  • Single-dose administration ensures 100% compliance compared to multi-day regimens 2
• Amoxicillin is better tolerated than erythromycin with fewer patients stopping medication due to side effects (2% vs 13%) 4

Important Contraindications

• Doxycycline, ofloxacin, and levofloxacin are contraindicated during pregnancy 1
• Erythromycin estolate is contraindicated during pregnancy due to drug-related hepatotoxicity 1

Follow-Up Recommendations

• Repeat testing (preferably by nucleic acid amplification test) 3 weeks after completion of therapy is recommended for all pregnant women to ensure cure 1
• This is particularly important given the potential sequelae that might occur in both mother and neonate if the infection persists 1
• Sexual partners should be evaluated, tested, and treated if they had sexual contact with the patient during the 60 days preceding diagnosis 1
• Patients should abstain from sexual intercourse until they and their partners have completed treatment 1

Neonatal Considerations

• Untreated chlamydial infection can lead to perinatal transmission to the neonate, resulting in:
  • Conjunctivitis developing 5-12 days after birth 1
  • Subacute, afebrile pneumonia with onset at ages 1-3 months 1
• Neonatal ocular prophylaxis with silver nitrate or antibiotic ointments does not prevent chlamydial transmission but should be continued to prevent gonococcal ophthalmia 1

Clinical Pearls and Pitfalls

• The frequent gastrointestinal side effects of erythromycin often lead to poor compliance and treatment failure 1, 3
• Lower-dose 14-day erythromycin regimens may be considered if gastrointestinal tolerance is a concern 1
• HIV-positive pregnant women with chlamydia should receive the same treatment regimen as HIV-negative women 1
• Pregnant women under 25 years of age are at higher risk for chlamydial infection and should be targeted for screening 1