In a 22-year-old woman at 37 weeks gestation with a history of multiple sexually transmitted infections, which intervention is most appropriate to prevent neonatal conjunctivitis and blindness?

Treatment of Maternal Chlamydia at 37 Weeks Gestation to Prevent Neonatal Conjunctivitis

Azithromycin 1 g orally as a single dose should be administered immediately to this pregnant woman—maternal treatment is the most effective strategy to prevent neonatal chlamydial conjunctivitis and blindness, far superior to any postnatal intervention. 1

Why Maternal Treatment Is the Answer

The clinical scenario describes a woman at 37 weeks with multiple STD history presenting for her first antenatal visit, raising concern about chlamydial transmission to the newborn. The question asks about health promotion and illness prevention—not treatment of established neonatal disease.

Maternal Treatment Prevents Neonatal Disease

• Prenatal screening and treatment of pregnant women is explicitly stated as "the best method for preventing neonatal gonococcal and chlamydial disease" by the CDC, making maternal therapy the primary preventive strategy. 2

• The American College of Obstetricians and Gynecologists confirms that prenatal screening and treatment can prevent chlamydial infection among neonates, establishing maternal treatment as the most effective preventive approach. 1

• Azithromycin 1 g orally as a single dose is the CDC-recommended first-line treatment for pregnant women with suspected or confirmed chlamydial infection. 1

Why the Other Options Are Inadequate

Option A (Reassurance) is dangerous:

• C. trachomatis prevalence exceeds 5% among pregnant women regardless of socioeconomic status, and this patient has multiple STD risk factors. 2
• Neonatal transmission occurs in 60% of exposed infants, causing conjunctivitis in 23% and pneumonia in 21%. 3
• Chlamydia is the most frequent identifiable infectious cause of ophthalmia neonatorum. 2

Option C (Newborn screening after delivery) is reactive, not preventive:

• Screening detects disease after transmission has already occurred—it does not prevent infection. 2
• Neonatal conjunctivitis develops 5-12 days after birth, meaning the window for prevention has closed. 2
• Neonatal ocular prophylaxis with erythromycin or silver nitrate is ineffective in preventing perinatal transmission of chlamydial infection from mother to infant, though it does prevent gonococcal ophthalmia. 2, 4

Option D (Refer to Infectious Disease) delays definitive care:

• At 37 weeks gestation, delivery is imminent—referral wastes critical time when immediate treatment is indicated. 1
• Chlamydia treatment in pregnancy is straightforward and does not require subspecialty consultation. 1, 5

The Correct Treatment Regimen

• Azithromycin 1 g orally as a single dose is the preferred first-line therapy for pregnant women with chlamydial infection. 1

• Alternative regimens if azithromycin cannot be used include amoxicillin 500 mg orally three times daily for 7 days or erythromycin base 500 mg orally four times daily for 7 days. 1, 2

• Doxycycline, ofloxacin, levofloxacin, and all fluoroquinolones are absolutely contraindicated in pregnancy due to teratogenic risk. 1, 5

Additional Management Considerations

• Test for co-infection with N. gonorrhoeae, as coinfection rates are substantial; if confirmed, add ceftriaxone 250 mg IM as a single dose. 1

• Repeat testing 3 weeks after completion of therapy is mandatory for all pregnant women to ensure therapeutic cure, unlike non-pregnant patients where test-of-cure is not routinely recommended. 1

• Sexual partner(s) must be evaluated and treated empirically to prevent reinfection. 1

• Both patient and partner must abstain from sexual intercourse for 7 days after initiating treatment and until all partners complete therapy. 1

Critical Pitfalls to Avoid

• Do not delay treatment while awaiting test results in a patient at 37 weeks with high-risk history—empiric treatment is appropriate given the imminent delivery and high prevalence of infection. 1

• Do not rely on neonatal ocular prophylaxis alone—erythromycin ophthalmic ointment given at birth does not prevent chlamydial conjunctivitis or nasopharyngeal colonization, though it should still be administered to prevent gonococcal ophthalmia. 2, 6, 4

• Do not use erythromycin estolate in pregnancy—it is contraindicated due to drug-related hepatotoxicity. 2, 1