INTERLEUKIN-8 CONCENTRATIONS IN AMNIOTIC-FLUID AND PERIPHERAL VENOUS PLASMA HUMAN-PREGNANCY AND PARTURITION

To establish the gestational and labour-associated changes in interleu kin 8 (IL-8) release, we have determined the concentration of this cyt okine in maternal peripheral plasma and amniotic fluid from 15 weeks o f gestation to term and in association with spontaneous-onset labour a t term and preterm. No statistically significant changes in peripheral plasma IL-8 concentration were observed during pregnancy or in associ ation with labour onset (mean concentration 56.5 +/- 14.5 ng/l, N = 64 ). The IL-8 concentrations in amniotic fluid were up to 50-fold greate r than those observed in peripheral plasma (p<0.05) and increased sign ificantly (p<0.05) during pregnancy. At term, but before the onset of labour, amniotic fluid concentrations of IL-8 averaged 969.2 +/- 553.5 ng/l (N = 12). In association with labour at term. IL-8 concentration s increased to 3895.8 +/- 1414.4 ng/l (N = 6, p<0.03). The concentrati on of IL-8 in amniotic fluid obtained from women in preterm labour ave raged 18 54.7 +/- 1352.6 ng/l (N = 6) but was not statistically differ ent from the concentration of IL-8 in amniotic fluid obtained from ges tational aged-matched non-labouring controls. Although the precise rol e of intrauterine IL-8 at the time of parturition awaits elucidation, these data support the concept that this cytokine may be involved in t he biochemical events associated with the onset and/or propagation of normal labour in the human.