What are the latest guidelines for the management (mx) of preterm labor?

Latest Guidelines for Management of Preterm Labour

The management of preterm labor requires a structured approach based on gestational age, with specific interventions including antibiotics, corticosteroids, magnesium sulfate, and tocolytics depending on clinical circumstances. 1, 2

Diagnosis and Initial Assessment

• Initial assessment should include evaluation for signs of infection, placental abruption, and fetal well-being 2
• Cervical length measurement by transvaginal ultrasound is the most reliable diagnostic tool for differentiating between threatened preterm labor and true preterm labor 3
• Digital cervical examination should be performed to assess dilation and effacement 3
• Fetal biometry, amniotic fluid volume assessment, and fetal Doppler waveform analysis should be performed at first diagnosis 2

Management Based on Gestational Age

Previable PPROM (<20 weeks)

• All patients with previable PPROM should be offered abortion care due to high maternal risks and poor fetal outcomes 1
• Expectant management can be offered in absence of contraindications 1
• Shared decision-making is recommended regarding antibiotic use 2, 4

Periviable PPROM (20-23 6/7 weeks)

• Consider antibiotics to prolong latency (GRADE 2C) 1, 4
• Antenatal corticosteroids and magnesium sulfate are not recommended until the time when neonatal resuscitation would be appropriate 1

PPROM ≥24 weeks

• Antibiotics are strongly recommended (GRADE 1B) 1, 4
• Antenatal corticosteroids should be administered between 24+0 and 34+0 weeks gestation 2, 5
• Magnesium sulfate is recommended for fetal neuroprotection when delivery is anticipated before 32 weeks 2, 4

Pharmacological Management

Antibiotics

• Recommended 7-day course: IV ampicillin and erythromycin for 48 hours followed by oral amoxicillin and erythromycin for 5 days 2
• Azithromycin can replace erythromycin if unavailable 2, 4
• Avoid amoxicillin-clavulanic acid due to increased risk of necrotizing enterocolitis 2, 4

Antenatal Corticosteroids

• Administer between 24+0 and 34+0 weeks gestation to accelerate fetal lung maturity 2, 5
• Significantly reduces neonatal mortality, intracranial hemorrhage, necrotizing enterocolitis, and neonatal infection 6
• Betamethasone and dexamethasone are more effective than less potent corticosteroids 7

Magnesium Sulfate

• Recommended for fetal neuroprotection when delivery is anticipated before 32 weeks 2, 4
• Provides neuroprotection and decreases the incidence of cerebral palsy in preterm infants 6

Tocolytics

• May allow time for administration of antenatal corticosteroids and transfer to a tertiary care facility 6
• Prostaglandin inhibitors and calcium channel blockers are preferred options 6
• Studies suggest nifedipine and indomethacin may delay delivery between 48-72 hours after 26 weeks of gestation 1
• No consistent data showing improved newborn outcomes at any gestational age 1

Cerclage Management

• For emergency ("rescue") cerclage when fetal membranes are visible at or past the external cervical os, can be considered in the absence of uterine contractions or PPROM at <24 weeks gestation 1
• After previable or periviable PPROM, it is reasonable to either remove the cerclage or leave it in situ after discussing risks and benefits 1

Monitoring and Follow-up

• Initial observation in hospital is reasonable to ensure stability 2
• Monitor for signs of maternal complications such as hemorrhage or infection 2
• Daily temperature monitoring to screen for maternal fever 2
• Weekly outpatient visits for assessment of maternal vital signs, fetal heart rate, physical examination, and possible laboratory evaluation 2

Common Pitfalls to Avoid

• Delaying diagnosis and treatment of intraamniotic infection due to absence of maternal fever 2
• Using amoxicillin-clavulanic acid, which increases risk of necrotizing enterocolitis 2, 4
• Prolonged or repeated antibiotic courses beyond what would be used for PPROM at later gestational ages 2, 4
• Administering antenatal corticosteroids and magnesium sulfate before the time when neonatal resuscitation would be appropriate 2, 4
• Using serial amnioinfusions and amniopatch (considered investigational) 1