The Problem of Confounding in Studies of the Effect of Maternal Drug Use on Pregnancy Outcome
Table 9
The effect of adjustment for some maternal characteristics on the effect of tricyclic antidepressants (TCAs) on the occurrence of infant cardiac defect and on the effect of antidepressants on preterm birth.
Cardiac defects after TCA
<37 weeks after antidepressants
Variables adjusted for
OR
95% CI
OR
95% CI
None (=crude)
1.64
1.14–2.36
1.60
1.50–1.72
Year of delivery
1.75
1.22–2.52
1.60
1.44–1.77
Year of delivery and maternal age
1.74
1.21–2.50
1.58
1.40–1.79
Year of delivery and maternal age and parity
1.74
1.21–2.50
1.54
1.37–1.77
Year of delivery and maternal age and smoking
1.72
1.19–2.49
1.44
1.23–1.69
Year of delivery and maternal age and smoking and BMI
