The determination of phospholipase A2 enzyme activity in the vaginal secretions of pregnant and non-pregnant women with bacterial vaginosis-and in culture exudates of its causative organisms

Abstract

Summary Bacterial vaginosis (BV) is presently being cited as a probable cause of premature labour, where it is thought that an abnormal excess of phospholipase A2 enzyme (PLA2 ), generated by infecting organisms, prematurely liberates prostaglandins, which trigger-off the labour process. PLA levels of pregnant and non-pregnant women, with and without BV infection were compared. The in vitro concentrations of PLA2 in broth cultures of infecting organisms were also measured. Mean PLA2 level in non-infected pregnant women was 777 units per mg but was raised to 1226 U/mg in those with BV ( P=0.001). Mean level in non-infected normal women was 21 U/mg, but was raised to 97 U/mg in those having BV ( P=0.001). PLA2 concentrations in broth cultures of the causative organisms showed that most Bacteroides strains produced the enzyme, having a mean concentration of 95 U/mg, but that it was generated by only 34% of Gardnerella vaginalis strains, their mean concentration being 32 U/mg.