Several scenarios during expectant management merit consideration. One is performance of digital cervical examination. Alexander and colleagues (2000) analyzed findings in women with PPROM expectantly managed between 24 and 32 weeks' gestation. hey compared those who had one or two digital cervical examinations with women who were not examined. Those who were examined had a rupture-to-delivery interval of 3 days compared with 5 days in those not examined. This diference did not worsen maternal or neonatal outcomes.
Rupture of membranes following second-trimester amniocentesis is uncommon (Chap. 14, p. 293). Compared with women with spontaneous rupture during the second trimester, Borgida and associates (2000) found that pregnancies complicated by PPROM after genetic amniocentesis resulted in signiicantly better perinatal outcomes. The perinatal survival rate was 91 percent. After counseling, afected women are typically managed expectantly as outpatients with serial surveillance of amnionic fluid volume (American College of Obstetricians and Gynecologists, 2016d). In the series cited above, the mean time to documentation of a normal amnionic fluid volume after amniocentesis approximated 2 weeks.
T ocolysis has been used in few studies. In women with ruptured membranes and lack of labor, prophylactic tocolysis does not improve neonatal outcomes but is associated with greater rates of chorioamnionitis (Mackeen, 2014). Similarly, therapeutic tocolysis-for those with ruptured membranes and labor-has also not provided signiicant perinatal beneit (Garite, 1987).
There is uncertainty regarding PPROM in the woman who has undergone cervical cerclage. McElrath and associates (2002) studied 114 women with a cerclage in place who later had ruptured membranes before 34 weeks. They were compared with 288 controls. Pregnancy outcomes were equivalent in both groups. Cerclage retention for more than 24 hours after preterm rupture of membranes may be associated with pregnancy prolongation, however, there is risk of intrauterine infection and its consequences (Giraldo-Isaza, 2011r; Laskin, 2012). As discussed in Chapter 18 (p. 357), such management is controversial.
With PPROM in general, the volume of amnionic luid remaining after rupture appears to have prognostic importance in pregnancies before 26 weeks. Hadi and colleagues (1994) described 178 pregnancies with ruptured membranes between 20 and 25 weeks. Almost 40 percent developed oligohydram nios, defined by the absence of fluid pockets measuring 2 em or more. Virtually all women with oligohydramnios delivered before 25 weeks, whereas 85 percent with adequate amnionic luid volume were delivered in the third trimester. Carroll and coworkers (1995) observed no cases of pulmonary hypoplasia in fetuses born after membrane rupture at 24 weeks or beyond.
This suggests that 23 weeks or less is the threshold for devel opment of lung hypoplasia (Chap. 7, p. 133). Further, when contemplating early expectant management, consideration is also given to oligohydramnios and resultant limb compression deformities (Chap. 11, p. 232).
Other risk factors have also been evaluated. First, in neo nates born to women with active herpetic lesions who were expectantly managed, the infectious morbidity risk appeared to be outweighed by risks associated with preterm delivery (Major, 2003). Second, Lewis and associates (2007) found that expectant management of women with PPROM and nonce phalic presentation was associated with a higher rate of umbili cal cord prolapse, especially before 26 weeks.