Table 2.

Unadjusted and adjusted^a odds ratios and 95% confidence intervals for postpartum depression by OXTR rs53576 genotype and OXTR methylation site -934, stratified by presence or absence of depression in pregnancy.

	Unadjusted (N = 545)			Adjusted (N = 500)
	Odds ratio	95% CI	p-valueb	Odds ratio	95% CI	p-valueb
No depression in pregnancy	n = 279c∗			n = 257d∗
Methylation (10% change) by rs53576			0.060		0.026
GG	2.07	(1.18, 3.63)		2.63	(1.37, 5.03)
A carrier	1.01	(0.62, 1.64)		1.00	(0.58, 1.73)
Depression in pregnancy	n = 266e∗			n = 243f∗
Methylation (10% change) by rs53576			0.172		0.155
GG	0.74	(0.46, 1.19)		0.63	(0.37, 1.09)
A carrier	1.18	(0.71, 1.98)		1.23	(0.61, 2.08)

^aAdjusted models control for psychosocial covariates: childhood life events, recent life events, family adversity, social support, and social network.

^bp-value for interaction within each group.

^cUnadjusted model represents 141 controls and 138 cases with no depression in pregnancy.

^dAdjusted model represents 128 controls and 129 cases with no depression in pregnancy.

^eUnadjusted model represents 135 controls and 131 cases with depression in pregnancy.

^fAdjusted model represents 123 controls and 120 cases with depression in pregnancy.

^∗See Supplementary Table S3 for a breakdown of each subgroup n by genotype.

The Table shows the odds ratios for PPD for each 10% increase in DNA methylation; p-values are for interaction between genotype and methylation level within each prenatal depression division. The overall p-values for three way interaction were 0.0192 (n = 545) and 0.0081 (n = 500) for unadjusted and adjusted interactions respectively. Main effects are not shown due to the two way interactions.