Neural tube defects: is a decreasing prevalence associated with a decrease in severity?

Amanda M Cotter; Sean F Daly

doi:10.1016/j.ejogrb.2004.06.028

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Neural tube defects: is a decreasing prevalence associated with a decrease in severity?

Amanda M Cotter·Sean F Daly

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Abstract

OBJECTIVE: Severe neural tube defects (NTDs) tend to occur with disproportionate frequency in areas of high prevalence. The objective of our study was to determine the birth prevalence of NTDs during a 25-year period at a single institution based in an area of high prevalence for NTDs and to investigate if a decreasing prevalence resulted in a change in the type of NTDs. STUDY DESIGN: All cases of NTD affected births born at the Coombe Women's Hospital during the interval 1975-1999 were reviewed. There were 171,260 births at the Coombe Women's Hospital between 1975 and 1999. During this interval, there were 522 NTD affected births. RESULTS: From 1975 until 1999 the prevalence of NTDs significantly decreased (P < 0.0001). This transition from high to low prevalence was associated with a significant decrease in severe forms of NTDs (P < 0.0001). This decreasing trend in rate and severity of NTD affected births was most dramatic prior to either food fortification or periconceptual folic acid supplementation. CONCLUSIONS: Our transition from high to low prevalence for NTDs has been associated with a significant decrease in severe forms of NTDs.

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Amanda M Cotter, Sean F Daly. 2005-04-01. Neural tube defects: is a decreasing prevalence associated with a decrease in severity?. https://doi.org/10.1016/j.ejogrb.2004.06.028

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