Objective: Preterm birth (PTB) is a major cause of neonatal morbidity and mortality. Reliable early biomarkers for predicting PB are limited. This study aimed to evaluate the effectiveness of first-trimester Hemoglobin, Albumin, Lymphocyte, and Platelet (HALP) scores and Prognostic Nutritional Index (PNI) scores in predicting PB.

Materials and Methods: This retrospective case-control study was conducted in a tertiary healthcare center from October 2023 to October 2024. Singleton pregnancies with preterm birth and term deliveries were included. Patients had complete blood count and serum albumin tests between 8–14 weeks of gestation, and groups were matched 1:1 for maternal age, gravidity, and parity. HALP and PNI scores were calculated and compared, and their predictive performance for PTB was analyzed.

Results: A total of 120 participants (60 PTB, 60 controls) were analyzed. Lymphocyte count and albumin levels were significantly lower, while platelet levels were higher in the PTB group (p<0.001). HALP and PNI scores were also significantly lower in the PTB group, with AUC values of 0.786 and 0.761, respectively.

Conclussion: First-trimester HALP and PNI scores may be promising biomarkers for predicting preterm birth. The HALP score demonstrated the highest specificity for PB prediction. These findings suggest that non-invasive, cost-effective, and easily accessible biomarkers could aid in early risk assessment. However, prospective, large-scale studies are required to confirm these results.