OBJECTIVE: Despite dietary supplement recommendations and implementation of food fortification with folic acid, NTDs remain an important public health concern. The objective of this study was to assess the potential reduction in NTDs associated with the use of folate-fortified OCs among women using OCs in the US.
DESIGN: We developed a decision-analytic model to show the benefits of elevated folate levels in US women who become pregnant within 5 months following discontinuation of OCs or who unintentionally became pregnant due to non compliance.
MATERIALS AND METHODS: Median baseline folate levels were estimated from the National Health and Nutrition Examination Surveys. The estimated gains in folate levels associated with using folate-fortified OCs were obtained from a recently reported clinical trial. Baseline RBC folate data on 144 women obtained from this trial were also examined in a separate analysis. The effects of using folate-containing dietary supplementation were considered in both analyses. Estimates of potential NTD risk were obtained by applying an established equation linking RBC folate levels with NTD risk to the estimated RBC folate levels in women using OCs with and without folate fortification.
RESULTS: Among women taking a folate-fortified OC compared to women taking a traditional OC, the model estimated that the number of NTD cases would decline by 31.4% and 23.7% using baseline folate levels from the NHANES data analysis and the clinical trial respectively. The difference is due to the lower median baseline folate level observed in the NHANES analysis compared with the clinical trial.
CONCLUSION: The results suggest folate-fortified OCs have the potential to further reduce the number of NTDs among women currently using OCs, even after the effects of dietary supplementation and food fortification have increased RBC folate levels.
