Periconceptional dietary intake of myo‐inositol and neural tube defects in offspring

BACKGROUND Periconceptional intake of nutrients in addition to folic acid may contribute to neural tube defect (NTD) etiologies; a likely candidate is myo-inositol. We investigated whether maternal periconceptional dietary intake of myo-inositol influenced NTD risk. METHODS Data were derived from a case-control study of fetuses and infants with NTDs among 1989–1991 California births. Interviews were conducted with mothers of 454 NTD cases and with mothers of 462 nonmalformed controls. A standard 100-item food frequency questionnaire was used to assess nutrient intake. RESULTS We observed small increases in risk, with increases slightly more evident for anencephaly, associated with intakes of myo-inositol less than the highest intake quartile, e.g., risk of anencephaly was 1.3 (0.7–2.4) among fetuses whose mothers consumed lowest versus highest intakes of myo-inositol. These small increases, however, were imprecise, and also did not indicate increasing risk with decreasing level of myo-inositol intake. Adjusted risk estimates did not differ considerably from their unadjusted counterparts. CONCLUSIONS Our results do not indicate that myo-inositol intake, as measured in this study, is strongly associated with risk of human NTDs. Birth Defects Research (Part A), 2005. © 2005 Wiley-Liss, Inc.