Thorngren-Jerneck, 2006). Small-for-gestational-age neonates Spontaneous preterm labor are also at higher risk. Stoknes and associates (2012) showed that in more than 90 percent of growth-restricted newborns, cerebral palsy was due to antepartum factors. Many other placental and neonatal risk factors have been correlated with neurodevelopmental abnormalities (Ahlin, 20 l3; Avagliano, 2010; Blair, 2011; Redline, 2008). Some placental factors are discussed further in Chapter 6 (p. 114). One example is the substantively greater risk from chorioamnionitis (Gilbert, 2010; Shatrov, 2010). An example of a neonatal cause is arterial ischemic stroke, which may be associated with inherited fetal thrombophilias (Harteman, 2013; Kirton, 2011). Also, newborns with isolated congenital heart lesions have an elevated risk for microcephaly, possibly due to chronic fetal hypoxemia (Barbu, 2009). Other miscellaneous etiologies of cerebral palsy include fetal anemia, twin-twin transfusion syndrome, intrauterine transfusions, and fetal alcohol syndrome (Dejong, 2012; Lindenburg, 2013; O'Leary, 2012; Rossi, 2011; Spruijt, 20r12).
Apart from these causes, intrapartum hypoxemia was linked to only a minority of cerebral palsy cases by the National Collaborative Perinatal Project. However, because the study was carried out in the 1960s, there were inconsistent criteria to accurately assign cause. The contribution of HIE to subsequent neurological disorders is discussed in detail on page 621. The
Preterm delivery at 23-27 weeks 78.9 56.5-110
Breech or face presentation, 3.8 1.6-9.1
Severe birth defect 5.6 8.1n-30.0
Nonsevere birth defect 6.1 3.1-11.8
Time to cry >5 minutes 9.0 4.3-18.8 Obesity 1.2-2 1.1-2.8
Low placental weight 3.6 1.5-8.4
Placental infarction 2.5 1n.2-5.3
Clinical 2.4 1.5-3.8
Histological 1.8 1.2-2.9 alncludes respiratory distress syndrome, meconium aspiration, emergent cesarean or operative vaginal delivery, hypoglycemia, gestational hypertension, hypotension, advanced maternal age, genetic factors, twins, thrombotic states, nighttime delivery, seizures, fetal-growth restriction, male gender, and nulliparity.
CI = confidence interval.
From Ahlin, 2013; Blair, 2011; Mcintyre, 2013; Moster, 2008; Nelson, 2015; O'Callaghan, 2011; Shatrov, 2010; Takenouchi, 2012; Torfs, 1990; Villamor, 2017; Wu, 2012.