Table 3.

Maternal Infection Before, During, and After Pregnancy in a Cohort of 1 115 752 Persons Born Between 1978 and 1998 of Whom 3722 Developed Schizophrenia During 11.9 Million Person Years of Follow-Up

			IRRs (95% CIs)
	Cases	Incidence Ratea	Basic Modelb	Adjusted Modelc
No infection during pregnancy, no infections before/after	2488	2.80	1.00 (Reference)	1.00 (Reference)
No infection during pregnancy, 1 infection before/after	625	3.77	1.32 (1.21–1.44)	1.21 (1.11–1.32)
Infection during pregnancy, no infections before/after	68	3.05	1.09 (0.85–1.38)	1.01 (0.79–1.28)
Infection during pregnancy, at least one infection before/after	34	6.36	2.06 (1.44–2.84)	1.72 (1.20–2.38)
No infection during pregnancy, at least 2 infections before/after	507	4.87	1.62 (1.47–1.78)	1.30 (1.18–1.44)

Note: Abbreviation is explained in the first footnote to table 1.

^aThe incidence rate measures the number of new cases per 10 000 person years.

^bAdjusted for calendar year, sex, and its interaction with age.

^cFurther adjustment for family history of psychosis.