JAMA 201 3 May 1;309( 1 7): '181n0-1n820.
24 weeks, only 1 percent of infants born at 22 weeks survived without neurodevelopmental impairment (Younge, 2017).
Somewhat similar results were published from Sweden (Serenius, 2013). his report details a national populationbased prospective study of all neonates born before 27 weeks. Shown in Table 42-3 are the survival and disability rates for 707 Swedish infants born alive from 22 to 26 weeks' gestation between 2004 and 2007 in Sweden. Compared with rates in the United States, rates of survival without neurodevelopmental impairment were higher in the Swedish cohort for infants born at 24 weeks during 2004 to 2007.
he Obstetric Care Consensus document also addresses management options based on the clinical characteristics of a given pregnancy. Nonmodiiable factors are fetal gender, weight, and plurality. Potentially modifiable antepartum and intrapartum factors include the location of delivery, intent to intervene
FIGURE 42-3 Mortality and neurodevelopmental outcomes at 18 to 22 months of corrected age by birth epoch in neonates born at 22 to 24 weeks. (Data from Younge N, Goldstein RF, Bann eM, et al: Survival and neurodevelopmental outcomes among periviable infants, N Engl J Med. 2017 Feb 16;376(7):617-628.)
EFM = electronic fetal monitoring; GBS = group B streptococcus; PPROM = preterm premature rupture of membranes. Data from the American College of Obstetricians and Gynecologists, 2017e; Raju, 2014.
by cesarean delivery or labor induction, and administration of antenatal corticosteroids and magnesium sulfate. Postnatal management addresses the initiation or withdrawal of intensive care after birth. Areas of general guidance were then reviewed for each week of gestation (Table 42-4).
Mode of delivery represents another dilemma because cesarean delivery at the threshold of viability is controversial. For example, if the fetus-neonate is perceived to be too immature for aggressive support, then cesarean delivery for common indications such as breech presentation or nonreassuring fetal heart rate patterns might be preempted. Moreover, observational studies have failed to document a benefit of cesarean delivery for the sole indication of periviability (Alirevic, 2013).
In a study of 2906 singletons between 24°17 and weeks eligible for attempted vaginal birth, 84 percent of cephalic presenting fetuses were delivered vaginally (Reddy, 2012). Neonatal mortality rates did not difer compared with those associated with planned cesarean delivery. For breech presentations, however, relative risk for mortality was threefold higher with attempted vaginal delivery. In another study, Werner and colleagues (2013) analyzed 20,231 newborns delivered at 24 to 34 weeks. Cesarean delivery did not protect against poor outcomes such as neonatal death, intraventricular hemorrhage, seizures, respiratory distress, and subdural hemorrhage. From these indings, the Obstetric Care Consensus proposes that cesarean delivery be considered for fetal indications at 23°(; to weeks. However, before 22 weeks, this route is reserved only for maternal indications.