Purpose: To investigate the association of perinatal variables with the birth of very low birth weight (VLBW) preterm newborns.
Methods: It was a retrospective study of the medical records of infants born after spontaneous preterm labor with admission to a neonatal intensive care unit. Preterm infants were divided into two groups: very low birth weight (VLBW) group (weight <1,500 g) and low birth weight (LBW) group (weight ≥1,500 g and <2,500 g). Prenatal variables such as maternal complications during pregnancy and childbirth/postpartum, and fetal/neonatal complications were investigated. Statistical analysis was performed using the Fisher exact test or χ2 test, with calculation of relative risk (RR), and the Student t test for comparison of group means, with the level of significance set at p≤0.05.
Results: Hemorrhagic comorbidities (p=0.006; RR=1.2) and hypertension (p=0.04; RR=1.5), surgical delivery (p=0.001; RR=0.5), gestational age <33 weeks (p< 0.001; RR=16.7) and Apgar score at 1st and 5th minute (p=0.006; RR=1.6; p=0.01; RR=1.9) were associated with the occurrence of VLBW. Infants with VLBW had a significant association with the occurrence of metabolic comorbidities (p=0.01; RR=1.8), neurological (p=0.01; RR=1.7) and infectious diseases (p=0.001; RR=1.9), hospitalization >4 weeks (p=0.02; RR=1.8) and early neonatal death (p=0.0001; RR=2.9).
Conclusions: Factors such as hypertension and bleeding comorbidities during delivery and management of gestational age of less than 33 weeks were associated with the birth of VLBW newborns. This group of infants also showed higher RR for the occurrence of early neonatal death.