What is the recommended treatment for a 33 1/7 weeks pregnant patient with spontaneous rupture of membranes, a history of smoking 5-6 cigarettes per day, stable vital signs, and no signs of labor or infection?

Management of Preterm Premature Rupture of Membranes at 33 1/7 Weeks

The correct answer is (b) Magnesium sulfate for neuroprotection, though antibiotics (specifically ampicillin plus erythromycin, NOT amoxicillin-clavulanate) should also be administered. At 33 1/7 weeks gestation with confirmed PPROM, the priority interventions are magnesium sulfate for fetal neuroprotection and appropriate antibiotic prophylaxis to reduce maternal and neonatal infectious morbidity.

Why Each Option Is or Is Not Recommended

Amoxicillin-Clavulanate (Option A): Contraindicated

• Amoxicillin-clavulanate (Augmentin) should never be used in PPROM management due to significantly increased risk of neonatal necrotizing enterocolitis 1, 2, 3.
• The sulbactam component specifically increases this devastating neonatal complication 1.
• This is a critical pitfall to avoid in PPROM management 2, 3.

Magnesium Sulfate (Option B): Strongly Recommended

• Magnesium sulfate for fetal neuroprotection is indicated for pregnancies <34 weeks with anticipated delivery (based on standard obstetric guidelines, though not explicitly detailed in the provided evidence).
• At 33 1/7 weeks with PPROM, delivery is typically anticipated within 24-48 hours, making neuroprotection a priority.
• This reduces the risk of cerebral palsy and improves long-term neurological outcomes in preterm infants.

Dexamethasone (Option C): May Be Considered But Less Priority

• Antenatal corticosteroids are typically most beneficial when administered between 24-34 weeks gestation 4.
• At 33 1/7 weeks, the patient is near the upper limit where corticosteroid benefit diminishes.
• If the patient has not received a prior course, corticosteroids could be considered, but this is not the single best answer given the options.

Nifedipine (Option D): Not Indicated

• Tocolysis with nifedipine is contraindicated in PPROM without active labor 2, 3.
• The patient denies contractions, so there is no labor to suppress.
• Prolonging pregnancy with tocolysis in PPROM increases infection risk without clear benefit at this gestational age.

Essential Concurrent Management

Antibiotic Prophylaxis: Mandatory

• Administer IV ampicillin plus erythromycin for 48 hours, followed by oral amoxicillin (without clavulanate) plus erythromycin for 5 additional days (total 7-day course) 1, 2, 3.
• This regimen prolongs pregnancy latency, reduces maternal infection and chorioamnionitis, and decreases neonatal morbidity with GRADE 1B evidence 1, 2.
• GBS prophylaxis is mandatory for all preterm deliveries <37 weeks with ruptured membranes, regardless of known GBS status 2, 3.

Infection Monitoring

• Monitor for chorioamnionitis signs: maternal fever ≥38°C, maternal tachycardia, uterine tenderness, fetal tachycardia, and purulent vaginal discharge 1, 2.
• Do not wait for fever to diagnose intraamniotic infection—clinical symptoms may be subtle at earlier gestational ages 2, 3.
• Check maternal vital signs every 2-4 hours and maintain continuous fetal heart rate monitoring 3.

Delivery Planning

• At 33 1/7 weeks, expectant management is appropriate if no signs of infection or fetal compromise develop 3.
• After 34 weeks, the benefits of delivery outweigh risks of expectant management, and induction should be considered 3.
• The risk of infection increases significantly after 18 hours of membrane rupture 1.

Critical Pitfalls to Avoid

• Never use amoxicillin-clavulanate (Augmentin) in PPROM 1, 2, 3.
• Do not delay antibiotic administration beyond establishing IV access 2, 3.
• Do not use tocolytics in PPROM without active labor (general obstetric principle).
• Do not perform cesarean section based solely on PPROM without clear obstetric indication 2, 3.