Table 4.

Risk of low-grade gliomas and medulloblasoma/PNET with use of folic acid or any vitamins

PrepregnancyTrimester 1Trimesters 2/3
Cases/controlsORa (95% CI)Cases/controlsORa (95% CI)Cases/controlsORa (95% CI)
Low-grade gliomas
 No folic acidb53/2271.0053/2271.0053/2271.00
 Any folic acid56/3570.64 (0.38–1.08)92/5790.74 (0.47–1.15)72/4440.73 (0.46–1.17)
 0.1–300 μg27/911.18 (0.64–2.18)36/1491.11 (0.65–1.89)32/1840.82 (0.48–1.40)
 300.1–450 μg11/1150.42 (0.20–0.89)26/1940.63 (0.36–1.10)19/1230.71 (0.37–1.35)
 >450.1 μg18/1510.44 (0.22–0.89)30/2360.57 (0.33–1.00)21/1370.63 (0.34–1.17)
P of linear trend<0.010.010.12
 Per 100 μg increase0.92 (0.84–1.00)0.94 (0.88–1.00)0.94 (0.87–1.01)
 No iron or vitamins b49/1891.00 (ref)49/1891.00 (ref)49/1891.00 (ref)
 Any iron or vitamins57/3840.59 (0.35–1.00)95/6090.70 (0.44–1.09)79/5000.69 (0.43–1.09)
Medulloblastoma/PNET
 No folic acidb22/2271.0022/2271.0022/2271.00
 Any folic acid25/3570.71 (0.33–1.52)48/5790.89 (0.48–1.67)38/4440.87 (0.45–1.71)
 0.1–300 μg7/910.70 (0.25–1.98)11/1490.84 (0.36–1.95)19/1841.04 (0.49–2.22)
 300.1–450 μg7/1150.63 (0.23–1.69)21/1941.08 (0.53–2.20)9/1230.68 (0.27–1.70)
 >450.1 μg11/1510.80 (0.31–2.02)16/2360.73 (0.34–1.57)10/1370.81 (0.33–1.95)
P of linear trend0.580.570.44
 Per 100 μg increase0.93 (0.82–1.06)0.96 (0.89–1.05)0.94 (0.84–1.05)
 No iron or vitaminsb19/1891.00 (ref)19/1891.00 (ref)19/1891.00 (ref)
 Any iron or vitamins26/3840.77 (0.34–1.70)49/6090.93 (0.48–1.78)42/5000.91 (0.46–1.79)
  • a Adjusted for matching variables, ethnicity, maternal age group, child's year of birth group, maternal education level, and data source.

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