Seasonal pattern of phototherapy: A study in the Sardinian population

The relationship between season of birth and human diseases is well known and it has been suggested that such a relationship could be mediated by seasonal and environmental effects on early events of extrauterine life. In this context the physiological increase of bilirubin occurring in all infants during the neonatal period may be of paramount importance. Indeed, recent studies suggest a beneficial action of bilirubin in the early stages of extrauterine life due to its protective action against secondary oxidants. The newborn infant is particularly sensible to oxidative damage, thus seasonal variation of bilirubin level in the first few days of life could influence further development and susceptibility to pathological manifestations. In the present paper we have analysed the seasonal effect on the level of the serum bilirubin during the neonatal period by an analysis of the incidence of phototherapy in a sample of 5540 infants born consecutively in the population of Sassari during the years 1993-96. The...