The Association Between ABO Blood Groups and Neonatal Clinical Outcomes Among Infants Admitted to the Neonatal Intensive Care Unit of Imam Khomeini Hospital in Ahvaz, Iran, During 2023–2024: A Retrospective Descriptive Study

ABSTRACT Background and Aims Since the discovery of major blood groups, the potential relationship between blood groups and various diseases has garnered interest. Most studies in this area have focused on adults, with comparatively fewer related to children, particularly newborns. The aim of this study was to investigate the association between ABO blood groups and neonatal clinical outcomes. Methods This retrospective descriptive study assessed the association between neonatal ABO blood groups and clinical outcomes among infants admitted to the Neonatal Intensive Care Unit of Imam Khomeini Hospital in Ahvaz, Iran, over 2 years (2023–2024). Infants were categorized by blood group (O vs. non‐O). Data on gestational age, delivery mode, intubation needs, sex, Apgar scores, birth weight, mechanical ventilation, proven sepsis incidence, surfactant use, antibiotic therapy, hospitalization duration, and mortality were collected and compared based on their blood groups. Results Medical records of 545 infants were analyzed; blood group O was the most common (38.2%), followed by B (29.2%), A (23.5%), and AB (9.2%). Rh‐positive infants comprised 92.8% of the cohort. No statistically significant associations were found between blood group and gestational age, birth weight, Apgar scores, or intubation needs. However, male infants were significantly more prevalent in non‐O blood groups (60.5% vs. 39.5%, p = 0.001). Clinical outcomes, including surfactant use, mechanical ventilation, sepsis, and mortality, did not differ significantly between the two groups. Conclusion The study highlights a sex disparity in blood group distribution but suggests that ABO blood type was not associated with differences in neonatal morbidity or mortality in unadjusted analyses in this population. Further research is warranted to explore underlying mechanisms.