Seasonal Variation in Solar Ultra Violet Radiation and Early Mortality in Extremely Preterm Infants.
Am J Perinatol. 2015 Jun 3. [Epub ahead of print]
Salas AA1, Smith KA2, Rodgers MD2, Phillips V2, Ambalavanan N2.
1Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
2Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama.
Background Vitamin D production during pregnancy promotes fetal lung development, a major determinant of infant survival after preterm birth. Because vitamin D synthesis in humans is regulated by solar ultraviolet B (UVB) radiation, we hypothesized that seasonal variation in solar UVB doses during fetal development would be associated with variation in neonatal mortality rates.
Methods This cohort study included infants born alive with gestational age (GA) between 23 and 28 weeks gestation admitted to a neonatal unit between 1996 and 2010. Three infant cohort groups were defined according to increasing intensities of solar UVB doses at 17 and 22 weeks gestation. The primary outcome was death during the first 28 days after birth.
Results Outcome data of 2,319 infants were analyzed. Mean birth weight was 830 ± 230 g and median gestational age was 26 weeks. Mortality rates were significantly different across groups (p = 0.04). High-intensity solar UVB doses were associated with lower mortality when compared with normal intensity solar UVB doses (hazard ratio: 0.70; 95% confidence interval: 0.54-0.91; p = 0.01).
Conclusion High-intensity solar UVB doses during fetal development seem to be associated with risk reduction of early mortality in preterm infants. Prospective studies are needed to validate these preliminary findings.
Most likely worse survival rate if mother were:
- dark skinned,
- heavily clothed,
- did not get much sun (fear the sun, working second or 3rd shift, etc.)
Would have had much better survival rate if mother had taken Vitamin D
And: Could have greatly reduced chance of preterm birth by taking vitamin D
- Pre-term birth rate cut in half by getting 4,000 IU of vitamin D during pregnancy.
Pages listed in BOTH the categories Pregnancy and UV
- More UV during first trimester, less Osteoporosis in offspring – June 2019
- Low Vitamin D if low UV (Pregnant Japanese, 2012) – March 2019
- Ultraviolet light (like Vitamin D) is great, especially while pregnant – Aug 2018
- Extreme preterm survival 30 percent less likely if little sunshine 23-28 weeks – June 2015
- Grassroots PDF and video updates May and June 2010