MEASUREMENT OF INTERLEUKIN-1-ALPHA AND INTERLEUKIN-6 IN PREGNANCY-ASSOCIATED TISSUES

The concentrations of interleukin-1 alpha (IL-1 alpha) and IL-6 in pre gnancy-associated tissues were investigated in term labour and deliver y in the absence of labour (elective Caesarean section). Samples of am niotic fluid, placenta, fetal membranes, umbilical venous and, where p ossible, umbilical arterial blood were collected at delivery (37-41 we eks of gestation). Maternal blood was sampled during labour. Fluid and tissue extracts were assayed for IL-1 alpha and IL-6 by radioimmunoas say. Placenta and membranes were examined histologically for evidence of infection. Concentrations of IL-1 alpha and IL-6 in amniotic fluid and membrane extract, and IL-1 alpha in maternal and fetal blood, were raised after the onset of labour. Concentrations of both cytokines in the placenta remained unchanged. There was a good correlation between concentrations of both cytokines in amniotic fluid and membranes. The re was also a significant correlation between concentrations of IL-1 a lpha and IL-6 in amniotic fluid, placenta and membranes. It is suggest ed that the fetal membranes or maternal decidua, but not the placenta, internal fetal or maternal tissues, are the main sources of IL-1 alph a and IL-6 during labour.