177 Incremental risk of chorioamnionitis associated with cervical examination


      Intra-amniotic infection is associated with significant neonatal morbidity and mortality. We sought to assess the association between number of cervical examinations and the risk of chorioamnionitis in term labor.

      Study Design

      This is a retrospective cohort study of term (≥37 weeks), singleton pregnancies who labored at our tertiary care center from 2005 to 2018. The primary outcome of chorioamnionitis was defined as maternal intrapartum fever (single oral temperature of >39°C or 38–38.9°C for 30 minutes) and one or more of the following: maternal leukocytosis, purulent cervical drainage, or fetal tachycardia. The primary exposure was the number of digital cervical exams documented in the medical record. Cox proportional hazard regression was used to model the effect of cervical examinations on the risk of chorioamnionitis while adjusting for internal monitoring, epidural use, meconium, maternal smoking, GBS, parity, BMI, duration of membrane rupture, labor induction and cesarean section.


      20,579 women met inclusion criteria and1,039 (5%) women were diagnosed with chorioamnionitis. The number of cervical exams was associated with an increased rate of chorioamnionitis after adjusting for potential confounders (hazard ratio [HR] 1.1, 95% confidence interval [CI] 1.04-1.1; p=<0.001). Each additional cervical exam confers an incremental risk of infection (OR=1.06 per exam, p<0.001). Women with greater than 7 cervical exams were 2.3 times more likely to develop chorioamnionitis (relative risk [RR] 2.3, 95% CI 1.3-4.0; p=<0.001). Duration of membrane rupture, labor induction, epidural placement, presence of meconium and cesarean delivery were all associated with chorioamnionitis after adjusting for confounders.


      In contrast to prior work, our study found that the number of cervical exams in term labor is an independent risk factor for developing chorioamnionitis after adjusting for confounders. Unnecessary cervical exams should be avoided during term labor management.
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