Amniotic fluid infection at term.

The incidence of amniotic fluid infection, determined by histological examination of the placenta and cord and cytological examination of gastric aspirate, was found to be high (52%) in term deliveries. A detailed histological system of grading the inflammatory response was used. No relationship was found between maternal nutritional factors or the baby's weight and inflammatory response, as judged by histological examination. The presence of pus cells in the gastric aspirate was of only limited diagnostic value. The absence of clinically obvious infection in the infants suggested amniotic fluid colonization without spread to the fetus.