The study involved 99 women who had previously had a pregnancy affected by a neural tube defect, and who were planning on becoming pregnant within the next year. Half of these women agreed to be randomly assigned to one of two groups; one group were instructed to take 5 mg of Folic acid each day and a placebo, and the second group were instructed to take 5 mg of Folic acid plus 1 mg of Inositol daily. Among the women who chose not be randomised, many decided to take folic acid and inositol in their next pregnancy.
Overall, fifty-seven of the women became pregnant during the study period. Results showed that none of the women taking both inositol and folic acid had pregnancies with a neural tube defect, compared to three of those who took only folic acid.
This research suggests that for those women for whom folic acid supplements are not sufficient to prevent a neural tube defect, taking inositol in addition to folic acid, may provide greater protection. A larger-scale study is now needed in order to in order to confirm the beneficial effects of inositol.