Table 3.

Risk of childhood brain tumors associated with maternal use of any supplements and specific supplements before or during the index pregnancya

PrepregnancyTrimester 1Trimesters 2/3
SupplementsCases/controlsOR (95% CI)Cases/controlsOR (95% CI)Cases/ControlsOR (95% CI)
No folic acid or ironb97/2021.0097/2021.0097/2021.00
Folic acid with iron54/1330.81 (0.48–1.37)100/2890.78 (0.52–1.19)105/3170.78 (0.52–1.18)
Folic acid without iron54/2240.56 (0.35–0.89)98/2900.83 (0.56–1.22)55/1270.91 (0.58–1.43)
No ironb188/4641.00188/4641.00188/4641.00
Any iron55/1400.98 (0.65–1.47)104/3050.87 (0.63–1.20)116/3570.86 (0.63–1.17)
No vitamin B6 or B12b225/5751.00225/5751.00225/5751.00
Any vitamin B6 or B1249/1241.03 (0.68–1.56)78/2340.89 (0.63–1.26)85/2530.92 (0.66–1.29)
No vitamin Cb228/5751.00228/5751.00228/5751.00
Any vitamin C47/1270.96 (0.64–1.46)73/2330.83 (0.59–1.18)83/2580.87 (0.62–1.21)
No vitamin Ab258/6551.00258/6551.00258/6551.00
Any vitamin A29/721.17 (0.72–1.90)48/1610.81 (0.56–1.19)59/1840.88 (0.62–1.26)
No iron or vitaminsb95/1891.0095/1891.0095/1891.00
Any iron or vitamins114/3840.68 (0.46–1.01)204/6090.80 (0.57–1.12)178/5000.79 (0.56–1.12)
No folic acid, iron or other vitaminsb97/2011.0097/2011.0097/2011.00
Any folic acid without iron or vitamins B6, B12, C, A32/1250.55 (0.32–0.93)81/2220.83 (0.56–1.24)49/1140.87 (0.54–1.39)
  • aBased on FFQ data, adjusted for frequency matching variables (age, sex, state of residence), ethnicity, maternal age group, child's year of birth group, maternal education level, and data source. ORs were not adjusted for other micronutrients as there were too few subjects taking some vitamins.

  • bReference level: no supplement of this type in any period.