Results
In 2010 - 2016, a total of 32 332 women gave birth in the study center. The exclusion criteria met 6,958 women. Finally, 25,063 women were included in the analysis. The average age of women in the study was 31.07 + 4.23 years (the youngest woman was 15 years old, and the oldest was 48 years old). Figure 2 presents the distribution of the study group by age. The mean gestational age in the study group was 39.15 weeks, in children, the predominant gender was male (51.1%), and the average birth weight was 3440.76 g. The primary composite endpoint occurred in 10,578 (42.2%) women. Among the components of the primary endpoint, the most common was oxytocin augmentation (17%) and unplanned caesarean section (13.8%), the most rarely intrauterine fetal death (0.1%), third or fourth-degree perineal lacerations (0.1%) and forceps delivery (0.1%). There was a significant difference between women characteristics in which the primary endpoint occurred and the others. A comparison of the subgroups examined depending on the occurrence of the primary endpoint is presented in Table 2. Age is an important risk factor for the primary endpoint in the whole study group. Its significance is unevenly distributed in the population - with the age of a woman, every subsequent year of life increases the risk of pregnancy and childbirth complications. In the subgroup of women after 20 or 25 years of age, the risk of a primary endpoint (respectively OR = 1.016 [95% CI 1.009-1.023] and 1.023 [95% CI 1.014-1.031]) with each year of life increases to a much lesser extent than in the subset of women over 35 years of age. (OR = 1.079 [95% CI 1.041-1.117]). The relationship between the age of women and the risk of the primary composite endpoint is shown in Figure 3.