Low Birth Weight and Adverse Neonatal Outcomes: A Retrospective Cohort Study

Abstract

Background: Low birth weight (LBW) remains an important predictor of neonatal morbidity and mortality. Infants born with LBW are more vulnerable to respiratory, metabolic, infectious, and survival-related complications during the neonatal period.

Objective: This study aimed to examine the association between LBW and adverse neonatal outcomes.

Methods: This retrospective cohort study included 1,250 live-born singleton neonates delivered between January and December 2025. The study population consisted of all eligible neonates with complete records of birth weight and neonatal outcomes. Neonates were classified into LBW (<2,500 g) and non-LBW (≥2,500 g) groups. The primary outcome was a composite of adverse neonatal outcomes, including NICU admission, respiratory distress, neonatal hypoglycemia, neonatal sepsis, phototherapy-requiring jaundice, low fifth-minute Apgar score, and neonatal death. Risk ratios were estimated using multivariable regression analysis.

Results: Of 1,250 neonates, 180 (14.4%) had LBW. Adverse neonatal outcomes were more frequent among LBW infants than among non-LBW infants (48.9% vs. 16.8%). After adjustment for maternal and obstetric factors, LBW was significantly associated with a higher risk of adverse neonatal outcomes (adjusted RR = 2.31; 95% CI: 1.78–2.99).

Conclusion: LBW was independently associated with an increased risk of adverse neonatal outcomes. Early identification of high-risk pregnancies and strengthened neonatal care are essential to improve outcomes among LBW infants.