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Postterm infant

Steven Ringer, MD, PhD
Section Editor
Leonard E Weisman, MD
Deputy Editor
Melanie S Kim, MD


Postterm infants are born at a gestational age (GA) greater than 42 weeks or 294 days from the first day of the last menstrual period. Postterm infants have higher rates of morbidity and mortality than term infants.

The epidemiology, clinical manifestations, neonatal management, and outcome of postterm infants will be reviewed here.


The incidence of postterm births varies with different patient populations and is dependent on a number of factors, such as the percentage of primigravid women, and local practice patterns regarding the rates of scheduled cesarean delivery and routine labor induction.

In the United States, postterm births have decreased from 11 percent of all births in 1990 to 5.5 percent of births in 2009 [1].

In a population-based Norwegian study, the reported incidence of postterm deliveries was 7.6 percent from 1989 to 1999 [2].

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Literature review current through: Nov 2017. | This topic last updated: Jul 25, 2017.
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