Intact chorioamniotic membranes serve as a protective barrier against bacterial infection. Rupture of the membrane exposes the uterine
surface to bacteria from the birth canal. The vaginal fluid
with bacterial flora is drawn into the uterus when it relaxes
between contractions during labor. Women undergoing labor
for more than six to eight hours in the presence of ruptured
membranes should be considered at high risk for developing endometritis.
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Other risk factors for SSIs after cesarean
delivery include systemic illness, poor hygiene, obesity, and
anemia.