From: Maternal drug use and the risk of anorectal malformations: systematic review and meta-analysis
 | Maternal use of dietary supplements |  | |||
---|---|---|---|---|---|
Ref. | First author, year | Exposure | ORcrude [95% CI] | ORadj [95% CI] | Adjustment/matching factors |
[28] | Zwink, 2016 | Folic acid | 1.2 [0.54, 2.48] | 1.0 [0.29, 3.40] | Adjusted for gender and birth year of the child, maternal age and BMI |
Multivitamins | 0.5 [0.11, 2.46] | 1.2 [0.21, 7.00] | |||
[53] | Zwink and Choinitzki, 2015 | Folic acid | 0.9 [0.49, 1.55]b | – | – |
0.8 [0.39, 1.83]c | – |  | |||
0.9 [0.57, 1.50]a,d | – |  | |||
Iron | 0.9 [0.43, 2.05]b | – |  | ||
2.4 [0.62, 10.72]c | – |  | |||
Multivitamins | 1.8 [0.61, 5.60]b | – |  | ||
0.5 [0.18, 1.46]c | – |  | |||
1.1 [0.48, 2.36]a,d | – |  | |||
[57] | Gilboa, 2014 | Vitamin E | – | 1.1 [0.65, 1.74]g | Adjusted for study center and maternal total energy intake, folate intake (dietary folate equivalents), race/ethnicity, age, education, pre-pregnancy body mass index, smoking, alcohol use and use of folic acid supplements |
 | 1.7 [1.01, 2.72]h | ||||
 | 1.5 [0.88, 2.51]i | ||||
[41] | Wijers, 2014 | Folic acid | – | 1.1 [0.8, 1.4]j | Adjusted for maternal education |
– | 1.0 [0.7, 1.5]k | ||||
– | 1.1 [0.7, 1.6]l | ||||
[27] | van Rooij, 2010 | Folic acid | 1.0 [0.6, 1.7] | – | – |
Multivitamins | 1.6 [1.0, 2.7] | – |  | ||
[77] | Källén, 2007 | Folic acid | 0.9 [0.51, 1.69]a | 1.0 [0.55, 1.84] | Year of birth, maternal age, parity, maternal smoking, and number of previous miscarriages |
[66] | Czeizel, 2004 | Folic acid | 0.5 [0.17, 1.23]e | – | – |
0.4 [0.17, 0.88]f | – |  | |||
Multivitamins | 0.2 [0.02, 1.69] | – |  | ||
[69] | Czeizel, 2004 | Multivitamins | 0.3 [0.01, 2.35] | – | – |
[6] | Correa, 2003 | Multivitamins | 0.9 [0.45, 1.67] | – | – |
[51] | Myers, 2001 | Folic acid | 0.5 [0.29, 0.88]m,n | 0.6 [0.33, 1.07]m,n | Maternal age |
0.5 [0.24, 1.04]m,o | 0.7 [0.31, 1.42]m,o | ||||
0.9 [0.28, 2.96]m,p | 0.9 [0.27, 3.06]m,p | ||||
0.3 [0.05, 1.24]m,q | 0.3 [0.05, 1.38]m,q |