Overview of preterm labor and birth
- Charles J Lockwood, MD, MHCM
Charles J Lockwood, MD, MHCM
- Section Editor — Obstetrics
- Senior Vice President, USF Health
- Dean, Morsani College of Medicine
- Professor, Obstetrics and Gynecology
- University of South Florida
Preterm birth refers to a delivery that occurs before 370/7ths weeks of gestation. It may or may not be preceded by preterm labor. Although term pregnancy has been defined as 370/7ths to 416/7ths weeks of gestation, the period 370/7ths to 386/7ths weeks should be considered ‘early term’ because neonates born in this gestational age range have higher neonatal morbidity and mortality than infants born at ‘full term’ from 390/7ths to 406/7ths weeks [1,2].
Classification — Subtypes of preterm birth are variably defined.
By gestational age :
●Moderate preterm: 32 to <37 weeks
●Late preterm: 340/7ths to 366/7ths weeks
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- PRETERM BIRTH
- Pathogenesis of spontaneous preterm birth
- Epidemiology and risk factors for spontaneous preterm birth
- PRETERM LABOR
- Clinical manifestations
- Approach to the patient with suspected preterm labor
- - Initial evaluation
- - Triage based upon cervical length
- Cervical length >30 mm
- Cervical length 20 to 30 mm
- Cervical length <20 mm
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS