Neural Tube Defects in the North of Jordan: Is There a Seasonal Variation?

Abstract

Neural tube defects are serious birth defects of the brain and the spinal cord due to interference with neural tube closure about the 28th day after fertilization. Seasonal variation in the development of neural tube defects has been reported. The objective of this study was to demonstrate any association between the season of conception and the development of neural tube defects in the north of Jordan. For a 7-year period between January 2000 and December 2006, data of 78 neonates born with neural tube defect were analyzed regarding dates of conception in relation to the development of neural tube defects. More affected babies were conceived in the late summer and early autumn. The study demonstrated that seasonality affected the incidence of neural tube defects in the north of Jordan.

Risk Factors of Neural Tube Defects in Northern Iran

“…The incidence rate of NTDs was higher in the summer, but in Nili’s study in Tehran, birth in spring and summer was significantly associated with NTDs (7). Furthermore, Obeidat and Amarin’s study in Jordan showed that more NTD-affected babies were conceived in the late summer and early autumn and concluded that seasonality affected the incidence of NTDs in the north of Jordan (15). …”

Vitamin D and folate: A reciprocal environmental association based on seasonality and genetic disposition

“…Given that the 5,10‐methylene‐H 4 folate coenzyme is essential for both DNA‐thymidylate and methionine/methyl group biosynthesis, this finding might be important in considering reproductive success; thymidylate is needed for chromosome stability, methionine for epigenetic regulation. This biochemistry becomes even more relevant when one considers that neural tube defects display a seasonal occurrence (Behrooz & Gorjizadeh, ; Bound, Harvey, & Francis, ; Marzullo & Fraser, ; Obeidat & Amarin, ) possibly corresponding to annual fluctuations in folate levels (Bates, Prentice, & Paul, ; Jiang, Christian, Khatry, Wu, & West Jr., ; Lucock et al, ; van Rootselaar, ; Wickham, O'Broin, & Kevany, ) or other as yet unknown chronobiological phenomena.…”

Epidémiologie et facteurs de risque des anomalies de fermeture du tube neural: données marocaines

“…Le facteur saisonnier a été évoqué dans certaines séries, il existerait même un pic de fréquence en Grande-Bretagne et en Jordanie chez les enfants conçus au printemps [ 6 ].…”