Table 2 Associations between periconceptional exposures to tobacco

[39]

   van Rooij, 2010

Cigarette consumption before or during pregnancy

0.8 [0.5, 1.3]

0.61

1.8 [1.1, 2.9]^§

0.01

-

-

[37]

   Miller, 2009^§§

Non-smoker not exposed to ETS

Non-smoker exposed to ETS at home or work

Non-smoker exposed to ETS at home and work

Smoked < 0.5 pack/day

Smoked ≥0.5 pack/day

Any smoking

1.0 Reference

1.1 [0.8, 1.5]

1.4 [0.5, 4.0]

1.0 [0.5, 1.8]

1.2 [0.8, 1.7]

1.1 [0.8, 1.6]

-

-

-

None of the variables met the criteria

for confounding by the author; therefore,

only the unadjusted odds

ratios were presented

[31]

   Honein, 2001

Any smoking

1-5 cigarettes/day

6-10 cigarettes/day

11-20 cigarettes/day

≥21 cigarettes/day

PR: 1.19 [0.94, 1.50]

PR: 0.95 [0.60, 1.50]

PR: 1.38 [1.00, 1.90]

PR: 1.19 [0.80, 1.79]

PR: 0.94 [0.29, 2.98]

-

-

-

Adjusted for: maternal age,

education and race/ethnicity

[38]

   Stoll, 1997

Any smoking

0.98 [0.94, 1.02]

-

-

-

-

   Cornel, 1996

Any smoking

2.24 [1.15, 4.16]

0.01

-

-

-

[30]

   Yuan, 1995

Any smoking

-

-

1.14 [0.59, 2.18]

0.70

1.75 [0.63, 4.87]

Matched by: maternal age groups

(5-years interval), sex, parity

and season of birth

[33]

   Shiono, 1986

Any smoking

0.41 [0.09, 1.87]

0.25

-

-

-

[42]

   Angerpointer, 1981

Any smoking

≥5 cigarettes per day

0.95 [0.45, 1.99]*

0.99 [0.46, 2.14]^†

1.20 [0.47, 3.10]^‡

0.63 [0.25, 1.57]^#

2.30 [1.00, 5.31]*

2.92 [1.16, 7.37]^†

1.58 [0.51, 4.83]^#

0.89

0.98

0.70

0.32

-

-

-

-