Increasing Trend and Influencing Factors of Pre-term Labor in Iran from 2005 to 2019

Background: Each year, an estimated 15 million pre-term births occur worldwide, with the incidence of pre-term labor on the rise globally. Complications arising from pre-term labor are a leading cause of mortality among children under the age of 5. Despite this, there has been limited research on the trend of pre-term labor in Iran. Objectives: This study aimed to assess the trend of pre-term labor and identify influencing factors on pre-term labor in Arak city, Iran, from 2005 to 2019. Methods: We analyzed a total of 89 307 live birth cases in Arak city from 2005 to 2019. The trend of pre-term labor over this study period was evaluated using statistical analysis software packages, specifically SPSS version 25. Linear trend analyses, as well as univariate and multivariate logistic regression analyses, were performed for statistical analysis. Results: The mean percentage of pre-term labor incidence during the first, second, and third 5-year periods was 8.9%, 10.3%, and 12.1%, respectively. Multivariate logistic regression analysis showed an increasing trend in pre-term labor incidence, even after adjusting for confounding factors (P < 0.001). Conclusions: The observed increasing trend in pre-term labor incidence indicates the necessity for a comprehensive preventive strategy. This strategy should focus on identifying high-risk pregnancies and implementing effective interventions. The increasing incidence of pre-term labor in Arak city highlights the necessity for preventive measures to reduce the burden of this condition.