Temporal and seasonal variations in incidence of stage II and III NEC—a 28-year epidemiologic study from tertiary NICUs in Connecticut, USA

Objective To investigate seasonality and temporal trends in the incidence of NEC. Study design A retrospective cohort study from two tertiary NICUs in northern and central Connecticut involving 16,761 infants admitted over a 28-year period. Various perinatal and neonatal risk factors were evaluated by univariate, multivariate, and spectral density analyses. Results Incidence of NEC was unchanged over the 28 years of study. Gestational age, birth weight, and birth-months (birth in April/May) were independently associated with stage II or III NEC even after adjusting for confounding factors ( p