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Published on: April 20, 2013
Birth season, photoperiod, and infancy refraction
1Department of Vision Science, New England College of Optometry, Boston, Massachusetts 02115, USA. DengL@neco.edu
Summary
Infants born with more daylight hours had slightly lower refractive errors. This suggests that light exposure shortly after birth may play a minor role in newborn refractive development.
Area of Science:
- Ophthalmology
- Developmental Biology
- Environmental Health
Background:
- Refractive error is a significant global health concern.
- Understanding early-life factors influencing refractive development is crucial for prevention and intervention.
Purpose of the Study:
- To examine the relationship between birth month, photoperiod, and infant refractive error.
- To determine if seasonal light exposure impacts early visual development.
Main Methods:
- Retrospective analysis of 722 infants with refractions measured at 1-3 months of age.
- Non-cycloplegic retinoscopy performed over 32 years.
- Photoperiod calculated based on daylight hours 30 days post-birth, categorized into quartiles.
Main Results:
- Infants born during periods of higher daylight hours exhibited lower mean spherical equivalent refraction (SER).
- A significantly higher percentage of infants with SER ≤-0.25 D were observed in the longest photoperiod group compared to the shortest.
- Similar trends were noted using an alternate seasonal classification, with summer births showing lower SER than winter births.
Conclusions:
- A statistically significant, albeit small, reduction in refraction was found in infants exposed to greater daylight soon after birth.
- These findings suggest a potential role for light exposure in modulating refractive error development in newborns.
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