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Overview of preterm labor and birth

INTRODUCTION

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].

PRETERM BIRTH

Classification — Subtypes of preterm birth are variably defined.

By gestational age [3]:

Moderate preterm: 32 to <37 weeks

Late preterm: 340/7ths to 366/7ths weeks

                 

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Literature review current through: Nov 2014. | This topic last updated: Sep 18, 2014.
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