Table 3.

Hierarchical regression analysis for prenatal and postnatal average daily cortisol output and postpartum depression

Variables	First trimester			Second trimester			Third trimester			Three months PPM
	R2	Standard error	Standard β	R2	Standard error	Standard β	R2	Standard error	Standard β	R2	Standard error	Standard β
	.06			.11*			.09			.07
Income Randomization group	.01	.34	−1.15	.01	−.36	−.12	.01	.34	−.88	.01	.34	−.16
	.05	1.16	−.22	.04	−2.38	−.22*	.04	1.17	−1.96	.04	1.18	−.21
Average cortisol output	.01	3.62	−.08	.05	−6.04	−.23*	.03	2.55	−1.78	.02	2.18	.14

Note: Randomization group was coded as 0 = attention control group and 1 = stress management group

^*p<.05,

^**p<.01