Table 4. Estimates of the mediating effect of preterm birth (<37 weeks gestation) in the association between maternal systemic lupus erythematosus and infant infections within the first 3 days and the first year of life. Direct, indirect and total effects are estimated with ORs and 95% CIs (OR 95% CI).

Mediator: preterm birth vs full term	Direct effectOR (95% CI)	Indirect effect through preterm birthOR (95% CI)	Total effectOR 95% CI	% mediated through preterm birth (95% CI)
Outcome
Any infection in the first 3 days of life	1.10 (0.60 to 1.61)	1.55 (1.18 to 1.93)	1.71 (1.00 to 2.43)	85 (27 to 144)
Any infection in the first year of life	1.10 (0.97 to 1.23)	1.03 (0.99 to 1.07)	1.13 (1.00 to 1.27)	28 (−10 to 66)

OR odds ratio; confidence interval. Models are adjusted for maternal age at delivery (continuous), maternal first-trimester smoking (yes/no/missing), and calendar year (continuous).