Antibacterial capacity in amniotic fluid in normal and complicated pregnancies.

The antibacterial activity against Escherichia coli K 12 in 153 samples of amniotic fluid (AF) in 15 to 40 weeks of pregnancy were investigated by a new micromethod. Fifty-six mothers had an uncomplicated pregnancy while various complications (maternal diabetes, cholestasis of pregnancy, pregnancy induced hypertension, blood group isoimmunization and fetal growth retardation) were present in 97 cases. A significant (p less than 0.001) improvement of antibacterial activity was observed with advancing pregnancy. The highest antibacterial activity in AF was observed in cases with intrauterine growth retardation. In other respects the effect of various diseases was negligible.