Table 3. Crude and adjusted OR for emotional distress and early and late preterm birth.

	Early preterm	Late preterm		Term
	22–31weeks	32–36 weeks		≥37 weeks
	n = 240*	n = 1,547*		n = 33,386*
	Crude	Crude	Adjusted †	Control
	OR (95% CI)	OR (95% CI)	OR (95% CI)
Emotional distress ‡ at 17 weeks	n = 240	n = 1,547	n = 1,547	n = 33,386
	0.79 (0.44; 1.41) P = 0.425	1.03 (0.83; 1.26) P = 0.818	0.97 (0.78;1.19) P = 0.747	1
Emotional distress ‡ at 30 weeks		n = 1,408	n = 1,408	n = 31,008
	Not calculated||	1.09 (0.87; 1.36) P = 0.447	1.00 (0.80;1.25) P = 0.993	1
Increase in emotional distress §		n = 1,374	n = 1,374	n = 30,261
	Not calculated||	1.15 (0.87; 1.52) P = 0.331	1.06 (0.80; 1.41) P = 0.671	1
Sustained high ED §		n = 1,354	n = 1,354	n = 29,967
	Not calculated||	1.01 (0.71; 1.43) P = 0.966	0.93 (0.66; 1.33) P = 0.696	1

*cases with covariates missing are excluded.

^†adjusted for maternal age, educational level, marital status, smoking, pre-pregnancy body mass index, late medical risk, history of spontaneous abortion, and neonate gender.

^‡emotional distress at 17 and 30 weeks are dichotomized variables, mean score ≥2 = 1.

^§compared to no emotional distress at 30 weeks.

^||OR not calculated because the exposure was measured simultaneously with the outcome variable.