Grade IV-parenchymal extension of hemorrhage.
If given at least 24 hours before delivery, corticosteroids prevent or reduce the incidence and severity ofIVH (Wei, 2016). A Consensus Development Conference of the NIH (1994) concluded that such therapy reduced rates of mortality, RDS, and IVH in preterm neonates born between 24 and 32 weeks' gestation. A second consensus statement by the NIH (2000) recommended that repeated courses of corticosteroids not be given (Chap. 42, p. 823).
Subsequently, the Maternal-Fetal Medicine Units Network reported that repeated corticosteroid courses were associated with some improved preterm neonatal outcomes, but also with reduced birthweight and increased risk for fetal-growth restriction (Wapner, 2006). Surveillance of this cohort through age 2 to 3 years found that children exposed to repeated versus singledose steroid courses did not difer signiicantly in physical or neurocognitive measures (Wapner, 2007). It was worrisome, however, that there was a nonsignificant 5.7-fold relative risk of CP in infants exposed to multiple steroid courses.
At the same time, the 2-year follow-up ofthe Australian CollaborativeTrialwas reported byCrowtherand coworkers (2007). In more than 1100 newborns, the incidence of CP was almost identical4.2 versus 4.8 percent-in those given repeated versus single-course steroids, respectively. More recently, it was reported that for those born before 28 weeks' gestation, if 10 days or more had passed since betamethasone administration, the incidence of severe IVH was higher (Liebowitz, 2016).
he most recent recommendations from the American College of0bstetricians and Gynecologists (2016a) are for a single course of corticosteroids for pregnant women between 24°/ weeks and 336/ weeks' gestation who are at risk for preterm delivery. They further note that those given their initial course more than 14 days prior and who have imminent risk of preterm delivery may receive a second "rescue" course. Antenatal corticosteroids are "considered" for 23°/ to 236/7 weeks and not recommended for pregnancies <23 weeks (American College of Obstetricians and Gynecologists, 2017c).
Although antenatal magnesium suate for those at risk for preterm delivery does not reduce the incidence ofIVH, it does ofer protection from neurodevelopmental impairment (Crowther, 2007; Doyle, 2009). The American College of Obstetricians and Gynecologists (2016b) recommends its use for this indication, as discussed further in Chapter 42 (p. 824). he eicacy of antenatal vitamin K and phenobarbital, as well as postnatal phenobarbital, have not been shown to consistently reduce the incidence ofIVH (Crowther, 2010a,b; Smit, 2013). Although vitamin E reduced IVH rates, the associated risk for sepsis was increased (Brion, 2003). One metaanalysis of the many randomized trials ofpostnatal indomethacin showed a reduction in IVH rates, but no improvement in rates of death or neurodevelopmental impairment (Fowlie, 2010).
he beneits of cesarean delivery compared with vaginal birth to lower IVH rates remains controversial. One metaanalysis reported that cesarean delivery for very-Iow-birthweight neonates had no efect on rates of severe IVH but did reduce overall IVH rates (Barzilay, 2016). Delayed cord clamping compared with immediate cord clamping has been reported to reduce the risk for IVH in preterm newborns (Rabe, 2012).