Preterm birth is a major cause of neonatal morbidity and mortality, with an increasing global incidence. Early identification of risk factors and timely intervention are crucial in improving perinatal outcomes. This study aims to describe the clinical and paraclinical characteristics of pregnant women diagnosed with threatened preterm labor between 28 and 34 weeks of gestation at Hanoi Obstetrics and Gynecology Hospital from September to December 2024. A cross-sectional descriptive study was conducted on 110 hospitalized pregnant women. The average maternal age was 28.78 ± 5.09 years, with a majority living in urban areas (56%) and working in administrative or office jobs (44.5%). A history of preterm birth was recorded in 11.8% of cases, while 58.2% were primigravida. The mean gestational age at presentation was 30.19 ± 2.05 weeks, with 71.8% of cases between 28 and 31 weeks. Common symptoms included abdominal pain (95.5%), vaginal or cervical infections (65.5%), and uterine contractions on obstetric monitoring (79.1%). Notably, cervical shortening (≤ 25 mm) was found in 82.7% of cases, with a mean cervical length of 19.50 ± 7.86 mm. These findings highlight the importance of cervical length measurement in predicting preterm birth risk and emphasize the need for targeted interventions to improve maternal and neonatal outcomes