Risk Factors for Chorioamnionitis

 

Factors with a relative risk >= 4:

(1) prolonged rupture of the membranes >= 12 hours

(2) prolonged labor (second stage > 2 hours, active labor > 12 hours)

(3) >= 3 digital exams with membrane rupture

(4) colonization with Group B streptococcus

(5) alcohol and tobacco use

(6) epidural anesthesia

 

Factors with a relative risk around 2:

(1) nulliparity

(2) bacterial vaginosis

(3) meconium-stained amniotic fluid

(4) internal monitoring

 

A history of chorioamnionitis in a previous pregnancy by itself does not increase the risk in a subsequent one.