Effects of digital vaginal examinations on latency period in preterm premature rupture of membranes.

OBJECTIVE

To compare the clinical outcome in patients with preterm premature rupture of membranes (PROM) who had a sterile speculum examination with those having a digital vaginal examination.

METHODS

We studied 271 singleton pregnancies complicated by preterm PROM from the Memorial Medical Center of Long Beach Perinatal Outreach program that met the criteria for expectant treatment from January 1986 to April 1990. Patients were not included in the study if they had multiple gestations, cerclage, advanced labor, or any indication for delivery on admission (eg, mature lung profile, chorioamnionitis). All subjects were maternal transports to our tertiary care facility and were managed similarly by our perinatal group. The women were questioned as to whether a digital vaginal examination had been performed before transport. Latency period and other obstetric characteristics were then compared. The latency period, defined as days from rupture of membranes until active intervention was initiated or labor began spontaneously, was also stratified by gestational age.

RESULTS

One hundred twenty-seven subjects had a digital vaginal examination and 144 had a sterile speculum examination. A significantly (P less than .0001) shorter mean latency period (2.1 +/- 4.0 versus 11.3 +/- 13.4 days) was found in those who had a digital vaginal examination. In addition, a shorter latency period was noted for each gestational age. No difference in uterine activity or cervical dilatation and effacement was noted between the groups on admission.

CONCLUSION

Digital vaginal examinations performed on patients whose pregnancies are complicated by preterm PROM appear to shorten significantly the latency period.