<unk>  is approximated to occur in about 4% of births in the United States. However, many other factors can increase the risk of<unk> . For example, in births with premature rupture of membranes (PROM), between 40 and 70% involve<unk> . Furthermore, clinical<unk>  is implicated in 12% of all cesarean deliveries. Some studies have shown that the risk of<unk>  is higher in those of African American ethnicity, those with immunosuppression, and those who smoke, use alcohol, or abuse drugs.
Chorioamnionitis
Placental abruption
Septic abortion
Toxic abortion
Obstructed labour
Prelabor rupture of membranes
Postpartum infections
Chondritis