How NICU Light Can Impact Your Preemie Baby’s Growth
Given the impact on light on health it makes sense to consider the impact of artificial light on the health of our most vulnerable members of society.
This research investigated the impact of a light-darkness cycle (LDC) on the growth and development of preterm infants in the Neonatal Intensive Care Unit (NICU), compared to constant bright light (CBL) conditions. The study was conducted in three hospitals in Mexico, involving 294 preterm infants. This is an important piece of research as the harmful effects of continuous bright light exposure on premature infant retinas has been well established. Also the use of CBL in most hospital services lacks solid science. So what did the investigators find and how can this information help you and your NICU baby?
Main Findings:
Weight Gain: Infants exposed to the light-darkness cycle gained weight earlier than those under constant bright light. By day 11, LDC infants had regained their birth weight, while CBL infants took until day 17.
Feeding Tolerance: Infants in the LDC group tolerated feeding better, with fewer issues like vomiting or gastric problems compared to those in the CBL group. They also consumed more milk.
Melatonin Levels: Infants in the LDC group developed a natural circadian rhythm of melatonin production, which helps regulate sleep and development. In contrast, the CBL infants showed constant melatonin levels without a clear day-night pattern.
Hospital Stay: The average hospital stay for LDC infants was significantly shorter (23 days) compared to CBL infants (33.7 days). This highlights that the light-darkness cycle can promote faster recovery and discharge.
Acrylic 'helmets' provided a surface to cover the infant's head.
Surprising Findings:
Faster Development of Melatonin Rhythms: One unexpected result was how quickly the infants in the light-darkness cycle (LDC) group developed a natural melatonin rhythm. Typically, melatonin rhythms are slower to develop in preterm infants, but the LDC group showed significant differences in day-night melatonin levels as early as day 6. This suggests that simply adjusting light exposure in the NICU can accelerate the development of important biological rhythms in preterm babies.
Shorter Hospital Stays: Another surprising finding was the significantly shorter hospital stays for infants in the LDC group. On average, these babies were discharged about 10 days earlier than those in the constant bright light (CBL) group. This finding is crucial because it not only benefits the infants' health but also reduces healthcare costs and the risk of hospital-acquired infections.
Recommendations:
Implement Light-Dark Cycles in NICUs: Adjusting light exposure to mimic natural day and night cycles can improve weight gain, feeding, and overall development in preterm infants.
Further Research: Although this study shows promising results, more research is needed to confirm the long-term benefits of light-darkness cycles for preterm infant care.
As a parent I would recommend talking to NICU staff about this research if they have not implemented similar protocols.
In simple terms, providing preterm babies with alternating light and dark periods (like a normal day) instead of constant light can help them grow faster, feed better, and leave the hospital sooner.
Sánchez-Sánchez, M., García, T.L., Heredia, D. et al. Effect of a light-darkness cycle on the body weight gain of preterm infants admitted to the neonatal intensive care unit. Sci Rep 12, 17569 (2022). https://doi.org/10.1038/s41598-022-22533-1
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10371081/
Johannes, C. & Dow, K. Does reducing light exposure decrease the incidence of retinopathy of prematurity in premature infants?. Paediatr. Child Health. 18, 298–300 (2013).
