Reproductive
Preconception folic-acid containing supplement use and associated factors in the Birth Defects Study To Evaluate Pregnancy exposureS (BD-STEPS) Anne Marie Darling* Anne Marie Darling Eirini Nestoridi Rashida Smith-Webb Wendy Nembhard Jenil Patel Bailey Wallace Shannon Evans Suzan Carmichael Gary Shaw Mahsa Yazdy
Background: Preconception folic acid supplementation has been recommended to prevent neural tube defects for the past 30 years, but there is suboptimal adherence to this recommendation. We sought to determine the prevalence of preconception folic acid-containing supplement use and associated factors in a population-based sample. Methods: This study included 1,371 BD-STEPS participants who gave birth to liveborn infants without birth defects between 2014-2019. Participants completed computer-assisted telephone interviews pertaining to their demographics, lifestyle, and health. Modified Poisson regression models were used to evaluate associations between these factors and folic acid-containing supplement use. Eight multivariable models were constructed based on confounders identified through directed acyclic graphs and implemented in the following sequence: pre-birth factors, education, geographic factors, pregnancy history, socioeconomic factors, pregnancy intention, lifestyle factors, and health status. Each model included all variables from the preceding models. Results: Only fifty percent of participants reported preconception folic acid-containing supplement use. Participants aged 25 years and younger were less likely to report supplement use compared to those aged 25-34 (RR 0.47, (95% CI 0.37, 0.60)). Participants planning to become pregnant were twice as likely to report supplement use (RR 2.11, (95% CI 1.77, 2.51)) compared to those who were not. Those who had health insurance (RR 1.49 (95% CI 1.09, 2.03)) and those with partners who had completed college (RR 1.48, (95% CI 1.00, 2.19)) were also more likely to report supplement use compared to those who did not. None of the other assessed variables showed an association. Conclusions: Adherence to folic-acid supplement recommendations continues to fall short of targets. Patterns of use are similar to those identified previously.