Introduction. The preterm delivery is defined as labour occurring between 22th gestational week and 37th non‑ended. The threatened preterm labour is an early stage of preterm labour. According to the paper, it is highly correlated with infection. On the base of recent research, it seems that the cervical length is a positive predictor of the preterm labour. Aim. The aim of the study was to compare inflammatory parameters and cervical length between patients with threatened preterm labour (treated or untreated) and healthy controls. Material and methods. The study group consisted of 79 women, who were admitted to the Gynecological and Obstetrics Clinical University Hospital in Poznań in 2011–2014 years because of the threatened preterm labour. Group I comprised patients before the treatment. Group II consisted of the patients during the treatment; group III included healthy controls. Blood samples were analised in the central laboratory of the hospital; The cervical length was measured during gynecological examination as well as the vaginal smears were taken. In the statistical analysis we used the Kruskal‑Wallis test and the ANOVA test; the level of statistical significance was adopted p value < 0.05. Results. The differences between compared three groups in the aspect of gestational age, C-reactive peptide, vaginal biocenosis and the presence of the urine bacteria were not significant. However, the leukocyte concentration in blood was significantly different in group I to II group (p = 0,04) as well as in group I to III group (p = 0,03). Moreover, reduction of cervical length in group II in comparison to group III was statistically significant (p = 0,0004), also in group I to III group (p = 0,003). Conclusions. To find out some additional parameters indicating the threat of preterm labour, some other biochemical markers should be considered and the number of patients in the study should be increased. The leukocytosis of peripheral blood and the cervical length could be helpful in prediction of preterm labour.

Key words: threatened preterm labour, cervical length, leukocytes.