Table 3.

Association between anxiety and depression status during pregnancy and preterm birth*

Anxiety and depression status during pregnancy†	Overall OR (95% CI)	Stratified by neighbourhood deprivation indices (quintile)
		Quintile 1‡ OR (95% CI)	Quintile 2 OR (95% CI)	Quintile 3 OR (95% CI)	Quintile 4 and 5§ OR (95% CI)
Unadjusted:
Presence of anxiety only	0.9 (0.6 to 1.5)	0.8 (0.3 to 2.2)	0.8 (0.3 to 2.2)	1.1 (0.4 to 2.9)	1.3 (0.5 to 2.9)
Presence of depression only	1.2 (0.7 to 2.1)	0.6 (0.2 to 2.1)	0.8 (0.2 to 3.6)	1.9 (0.7 to 4.2)	2.6 (0.9 to 6.1)
Presence of both anxiety and depression	1.6 (1.1 to 2.3)	0.2 (0.1 to 1.5)	1.3 (0.5 to 3.1)	2.8 (1.3 to 5.5)	2.5 (1.3 to 3.7)
Adjusted for parity, ethnicity, body mass index, maternal age, smoking, social support, maternal education and household total income:
Presence of anxiety only	0.8 (0.6 to 1.6)	0.7 (0.2 to 1.9)	0.7 (0.2 to 2.1)	1.0 (0.4 to 2.9)	1.0 (0.4 to 2.6)
Presence of depression only	1.3 (0.8 to 2.5)	0.7 (0.2 to 2.5)	0.9 (0.2 to 4.1)	1.7 (0.8 to 4.7)	2.1 (0.9 to 7.0)
Presence of both anxiety and depression	1.6 (1.1 to 2.3)	0.2 (0.1 to 1.5)	1.4 (0.6 to 3.3)	2.1 (1.2 to 5.8)	2.2 (1.3 to 4.0)

*Estimates were from analyses based on multiple imputation.

†Absence of both anxiety and depression as a reference group.

‡Quintile 1: least deprived neighbourhood.

§Quintile 5: most deprived neighbourhood (quintiles 4 and 5 were combined due to few or no cases in some strata).