[Markers of infection and inflammation in the amniotic fluid: therapeutic contribution of amniocentesis]

Abstract

A part of preterm labor with intact membranes seems to be related to amniotic infection or local inflammatory process. In these cases, amniotic fluid is collected by amniocentesis for bacteriological studies: amniotic cultures are positive in 10% and polymerase chain reaction (PCR) in 40-50%. Interleukin 6 (IL6) concentrations are elevated in cases with amniotic infection and in some cases with negative cultures. IL6 amniotic concentrations are predictive of premature delivery and neonatal morbidity. Matrix metalloproteinases (MMP) are endogenous enzymes implicated in membrane weakening. Amniotic concentrations of these enzymes seem to be predictive of premature delivery and neonatal prognosis. Furthermore, at the time of genetic amniocentesis, IL6 and MMP concentrations are markers for preterm delivery. In the second half of gestation, amniocentesis is a safe procedure complicated in less than 1% of cases, although specific evaluation in cases of premature labor is missing. Nevertheless, as long as there is no evidence of any benefit in this procedure, there is no indication for amniocentesis in premature labor with intact membranes in general practice.