An observational study of over 200 term and late-preterm neonates with significant jaundice assessed the efficacy of filtered sunlight treatment for jaundice. The infants were placed under canopies that filtered sunlight using commercial window-tinting films that removed most ultraviolet and much of the infrared spectrum of light, and allowed only effective levels of therapeutic blue light to pass through. The mean irradiance of the light was 38 microwatts per square cm per nanometer. This phototherapy was provided for a total of 258 days (among all infants) and was efficacious in 92% of phototherapy days. No infant developed sunburn or dehydration, although on one-third of the days the infants had to be removed from phototherapy for temperature-related adverse events.
A randomized trial of this intervention is in progress.