Chorioamnionitis (CA) is an inflammation of the amniochorionic membrane, and is a significant cause of maternal and neonatal morbidity. The aim of this study is to investigate the risk factors of CA and its association with adverse maternal, neonatal outcomes and mode of delivery. We performed retrospective case control observational study that enrolled 210 singleton deliveries in Riga Maternity Hospital at ≥37 weeks of gestation (2018-2019). 105 cases with clinically diagnosed CA were compared to control group of 105 labours. Clinical CA was defined as elevated temperature and one or more of the following: fetal tachycardia > 160 x/min, maternal tachycardia >100 x/min, maternal leucocytosis > 15 000/mm3, purulent/smelly discharge. The data were analysed using SPSS- Pearson Chi-Square, Independent Samples T and Mann-Whitney U Test with the cut of point of p<0.05. The average maternal body temperature in CA group was 38°C. Commonly the temperature rising point was during 1st (59%) and 2nd (24%) stage of labour. There were statistically significant differences in length of ruptured membranes (805,2±450,6 min; 761,7±406 min, p<0,001), the rate of labour induction (59/105; 35/105, p=0,001), uterine dysfunction (84/105; 50/105, p<0,001), use of epidural analgesia (90/105; 61/105, p<0,001), the length of 1st period (627,86±202,8 min; 434,44±206,1 min, p<0,001) and the 2nd stage of labour (84,86±52,84 min; 57,78±51,24 min, p< 0,001), presence of meconium stained amniotic fluid (42/105; 25/105, p=0,012), the rate of Caesarean sections (38/105; 14/105, p<0,001), cervical tears after vaginal delivery (25/67; 12/91, p<0,001) and blood loss (467,71±245,43 ml; 360,76±178,88 ml p<0.001). The need of antibacterial therapy postpartum in neonates was higher in CA group (50/105; 15/105, p<0,001). CA complications as increased Caesarean section rate and high blood loss are the risk factors for mother’s morbidity and mortality. It should be taken in to account managing delivery, prescribing adequate antibacterial therapy and postpartum haemorrhage prophylaxis.