The investigation deals with the study of amniotic fluid bioregulators (cytokines and nitric oxide - NO) in 48 pregnant women with impaired vaginal microbiocenosis and vaginitis during preterm labor. A control group comprised 21 women whose pregnancy was uncomplicated and whose labor was physiological. The authors established metabolic targets for interaction of interleukins and angiogenic factors, and their levels reflecting the pattern and degree of modification of the cytokine and angiogenic statuses of amniotic fluid in women with preterm labor at 34-37 weeks' gestation. At the same, there was an elevated level of proinflammatory cytokines (TNF-, IL-1, IL-6, and IL-8) and a low concentration of angiogenic compounds (NO, activity of NO synthase). The results of the study suggest that the proinflammatory cytokines are involved in the change of NO production. The found relationship between cytokines and angiogenic factors could identify a leading factor in the induction of preterm labor - an imbalance between the ratio of the proinflammatory cytokine TNF- to the angiogenic compound NO, which control calcium levels in the myometrial cells.