Objective of this research is to find out is there an association between immunohistochemical expression of Interleukin 6 and presence of RECK protein in fetal membranes of women who had late preterm delivery at 34-36+6/7 weeks and had histological features of chorioamnionitis and PPROM and a group of women who had spontaneous premature birth at the same gestational age without histological features of chorioamnionitis. Materials and methods: There have been 60 women who gave birth at gestational age of 34- 36+6/7 . They were divided into two groups (30 pregnant women in each group). In the first group there were women with histological features of chorioamnionitis who also had PPROM. In the second group were women who had spontaneous preterm delivery at the same gestational age without histological features of chorioamnionitis. Fetal membranes had been collected after delivery and after that immunohistochemistry was preformed using monoclonal antibodies against RECK protein and IL-6. The intensity of anti RECK and IL-6 cytoplasmic staining of placental membranes was categorized as: 0 - undetectable; 1 - weak; 2 – strong; according to the protocol of Scheller et al. (104). SPSS version 17.0 was used for statistical analysis. Results: No statistically significant difference has been found in the terms of the age of pregnant women, duration of pregnancy, parity and body mass index between two research groups. In the group of pregnant women who gave birth at gestational age of 34-36 and who had histological characteristics of chorioamnionitis and PPROM we found statistically significant weaker immunohistochemical expressiveness of RECK protein in comparison to those who gave spontaneous premature birth (χ2=4,29, p=0,04). In both research groups immunohistochemical expressiveness of IL-6 was very strong, but with no statistically significant difference (Fischer exact test= 0.61; p>0,05). Conclusion: In fetal membranes of women who had late preterm delivery histologically proven chorioamnionitis has impact on immunohistological expresiveness of RECK protein, but has no impact on the expression of IL-6.