Table 3:

Unadjusted and adjusted temporal trends in spontaneous stillbirths^* among births with a weight of at least 1000 g

Factor	Unadjusted OR^† (95% CI)	p value^‡	Adjusted OR^† (95% CI)	p value^‡
Year
2000	1.00 (ref)	–	1.00 (ref)	–
2001	0.99 (0.76–1.30)	0.96	0.98 (0.75–1.28)	0.9
2002	0.79 (0.60–1.05)	0.1	0.78 (0.58–1.03)	0.08
2003	0.84 (0.63–1.10)	0.2	0.77 (0.58–1.02)	0.07
2004	0.69 (0.51–0.92)	0.01	0.66 (0.49–0.89)	0.006
2005	0.77 (0.58–1.02)	0.07	0.73 (0.55–0.97)	0.03
2006	0.91 (0.69–1.19)	0.5	0.85 (0.64–1.11)	0.2
2007	0.85 (0.65–1.11)	0.2	0.79 (0.60–1.04)	0.09
2008	0.83 (0.63–1.09)	0.2	0.74 (0.56–0.98)	0.03
2009	0.63 (0.47–0.84)	0.002	0.58 (0.43–0.78)	< 0.001
2010	0.70 (0.53–0.94)	0.02	0.67 (0.50–0.90)	0.007
Age, yr
< 20	1.28 (0.92–1.79)	0.1	1.17 (0.84–1.63)	0.4
20–24	1.00 (ref)	–	1.00 (ref)	–
25–29	0.96 (0.78–1.17)	0.7	1.01 (0.82–1.23)	0.9
30–34	0.94 (0.77–1.14)	0.5	1.02 (0.83–1.24)	0.9
35–39	0.99 (0.80–1.23)	0.9	1.08 (0.86–1.35)	0.5
≥ 40	1.69 (1.26–2.27)	< 0.001	1.76 (1.30–2.37)	< 0.001
Parity
0	1.33 (1.16–1.51)	< 0.001	1.42 (1.24–1.62)	< 0.001
1–2	1.00 (ref)	–	1.00 (ref)	–
3–4	1.82 (1.41–2.34)	< 0.001	1.65 (1.28–2.13)	< 0.001
≥ 5	2.44 (1.48–4.03)	< 0.001	1.96 (1.18–3.25)	0.009
Weight before pregnancy, kg
< 60	1.11 (0.92–1.36)	0.3	1.10 (0.91–1.34)	0.3
60–69	1.00 (ref)	–	1.00 (ref)	–
70–79	1.44 (1.14–1.82)	0.003	1.45 (1.15–1.83)	0.002
80–89	1.11 (0.79–1.55)	0.5	1.13 (0.81–1.58)	0.5
≥ 90	1.78 (1.35–2.36)	< 0.001	1.84 (1.39–2.43)	< 0.001
Missing	2.12 (1.76–2.56)	< 0.001	2.16 (1.79–2.61)	< 0.001
Multiple birth	1.48 (1.09–2.01)	0.01	1.40 (1.02–1.91)	0.04

Note: CI = confidence interval, OR = odds ratio, ref = reference group.
↵* Excludes pregnancy terminations that resulted in stillbirth.
↵† The unadjusted ORs show the effect of each factor independent of the other factors; the adjusted ORs show the effect after adjustment for all other factors in the table.
↵‡ Wald χ² test.