PREMATURE LABOR .2. BACTERIAL SOURCES OF PHOSPHOLIPASE

  • 1 January 1981
    • journal article
    • research article
    • Vol. 57  (4) , 479-482
Abstract
Human term labor is thought to be initiated by amniotic and chorionic phospholipase A2, an enzyme that liberates arachidonic acid esters from the phospholipids of these membranes, leading to the synthesis of prostaglandins by the placental membranes. The striking association of premature labor with intrauterine infection or contamination, urinary tract infection and early neonatal sepsis led to a study of the microorganisms present in these infections for phospholipase A2 activity. Activity was found in Bacteroides fragilis, Peptostreptococcus, Fusobacterium necrophorum, viridans Streptococcus, S. faecalis, Streptococcus groups A and B, S. pneumoniae, Escherichia coli, Klebsiella, Staphylococcus epidermidis, Lactobacillus and Mycoplasma hominis. B. fragilis, Peptostreptococcus, Fusobacterium had the highest activities. The specific activities of phospholipase A2 from these organisms were several times higher than that of the membrane phospholipase A2 of the amnion and chorion. Premature labor may be initiated by micoorganisms with phospholipase A2 activity from endocervical and/or intrauterine contamination or infection, producing deacylation of arachidonic acid from amniotic phospholipids with increased concentrations of free arachidonic acid and increased prostaglandin synthesis, which triggers labor.