Whether preterm labor is induced or spontaneous, abnormalities of fetal heart rate and uterine contractions are sought. We prefer continuous electronic monitoring. Fetal tachycardia, especially with ruptured membranes, is suggestive of sepsis. Some evidence supports that intrapartum acidemia may intensiy some of the neonatal complications usually attributed to preterm delivery. For example, Morgan and associates (2017) found that metabolic acidemia signiicantly raised the risks related to prematurity in neonates delivered prior to 34 weeks' gestation. Low and colleagues (1995) observed that intrapartum acidosis-umbilical artery blood pH <7.0-had an important role in neonatal complications (Chap. 33, p. 621). Group B streptococcal infections are common and dangerous in the preterm neonate, and antimicrobial prophylaxis should be provided (Chap. 64, p. 1222).
In the absence of a relaxed vaginal outlet, an episiotomy for delivery may be necessary once the fetal head reaches the perineum. Perinatal outcome data do not support routine episiotomy or forceps delivery to protect the "fragile" preterm fetal head. Staf proicient in resuscitative techniques commensurate with the gestational age and fully oriented to any speciic problems should be present at delivery. Principles of resuscitation described in Chapter 32 (p. 608) are applicable. The importance of specialized personnel and facilities for preterm newborn care is underscored by the improved survival rates of these neonates when delivered in tertiary-care centers.
• Prevention of Intracranial Hemorrhage
Preterm newborns frequently have intracranial germinal matrix bleeding that can extend to more serious intraventricular hemorrhage (Chap. 34, p. 639). It was hypothesized that cesarean delivery to obviate trauma from labor and vaginal delivery might prevent these complications. his has not been validated by subsequent studies. Malloy (1991) analyzed 1765 newborns with birthweights < 1500 g and found that cesarean delivery did not lower the risk of mortality or intracranial hemorrhage. Anderson and colleagues (1988), however, made an interesting observation regarding the role of cesarean delivery in intracranial hemorrhage prevention. These hemorrhages correlated with exposure to active-phase labor. However, they emphasized that avoidance of active-phase labor is impossible in most preterm births because decisions for delivery route are not required until active labor is irmly established.
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