PREVALENCE AND RISK FACTORS OF PRETERM BIRTH AMONG PREGNANT ADOLESCENTS IN KUALA LUMPUR: A CROSS-SECTIONAL STUDY Introduction: Adolescent pregnancies are often associated with a higher risk of adverse outcomes, including preterm birth, which may lead to severe physiological and psychological health impacts on both mothers and children. Despite the acknowledged risks, there is a knowledge gap regarding the risk factors of preterm birth among pregnant adolescents. This study aimed to determine the prevalence and associated sociodemographic, maternal, intrapartum and neonatal factors of preterm birth among pregnant adolescents in Kuala Lumpur. Methods: A cross-sectional study was conducted in Kuala Lumpur, Malaysia, from March to June 2024. Samples were selected using simple random sampling from the Wilayah Persekutuan Kuala Lumpur and Putrajaya Department of Health pregnant adolescents’ line listing from 2019 to 2023. Simple and multiple logistic regression analyses were used to determine the factors associated with preterm birth. Results: A total of 175 pregnant adolescents were included in the study. The prevalence of preterm birth was 16%. Anaemia at booking (adjusted odds ratio [aOR]: 7.8; 95% confidence interval [CI]: 2.53, 23.997), history of preterm birth (aOR: 11.654; 95% CI: 1.517, 89.498), history of smoking (aOR: 6.89; 95% CI: 1.397, 34.002) and low birth weight (aOR: 12.503; 95% CI: 3.858, 40.522) were significantly associated with preterm birth. Conclusion: Targeted interventions to address anaemia, history of smoking, previous history of preterm births and low birth weight babies in adolescent pregnancies are crucial to reduce the incidence of preterm birth and improve maternal and infant health outcomes in this population among adolescents.