Regulation of interleukin 8 production in the term human placenta during labor and by antigestagens

Interleukin-8 appears to play a role in labor. This immune system protein is produced by many cells and attracts and activates white blood cells called neutrophils. Researchers tested placentas taken from five pregnant women after childbirth for the presence of interleukin-8. It was found in all samples. The production of interleukin-8 by the placental samples was increased by chemicals that inhibit progesterone. Neutrophils are known to secrete an enzyme called collagenase, which breaks down collagen and leads to softening of the cervix.