Differential levels of T helper cytokines in preeclampsia: pregnancy, labor and puerperium

Background. There are suggestions that T helper 1 cytokines may be detrimen tal to early pregnancy and T helper 2 cytokines protective of the pregnancy . Their role in preeclamptic pregnancy, labor and puerperium, is not clear. Materials and methods. Twenty-eight preeclamptic women and their matched co ntrols were evaluated, at the Departments of Obstetrics and Gynecology, Fac ulty of Medicine, Kuwait University and Maternity Hospital, Kuwait. Outcome measures evaluated were serum levels of TNF alpha and interleukin-4 at 12, 24, 36 weeks of gestation, advanced labor and at 1 hour and daily postpart um until they were undetectable, using ELISA technique. Results. T helper cytokines showed hi her serum levels in preeclampsia than normotensive pregnancy (p<0.01, 0.01), in established labor (p<0.05) and a t 1 hour postpartum (p<0.01 for IL-4) and p<0.02 for TNF alpha. There was s ignificant increase of IL-4 between 12 to 24 weeks in normal pregnancy comp ared to preeclampsia (p<0.001) but nor for TNF alpha. By 24 hours postpartu m, IL-4 was still detectable in eight parturients compared to one patient w ith detectable TNF alpha (p<0.04). Detectable IL-4 levels after 24 hours po stpartum were associated with intrauterine growth retardation (p<0.03). Conclusion. IL-4 has a dichotomous role in pregnancy. Normotensive pregnanc y is associated with high increase in IL-4 in the first half of the pregnan cy, but in the second half of pregnancy and puerperium, high levels of IL-4 are associated with preeclampsia.