Table 3. . Association of maternal glucose values during a second trimester oral glucose tolerance test with top four CpG sites identified in the epigenome-wide association study of second trimester maternal HbA1c (all z-scores).

CpG	Gene	Fasting glucose z-score (n = 412)		1 h glucose z-score (n = 412)		2 h glucose z-score (n = 412)		HbA1c second trimester z-score (n = 412)
		Effect estimates (95% CI)	p-value	Effect estimates (95% CI)	p-value	Effect estimates (95% CI)	p-value	Effect estimates (95% CI)	p-value
cg21645848	URGCP	-0.09 (-0.23, 0.05)	0.24	-0.06 (-0.20, 0.09)	0.47	-0.13 (-0.28, 0.03)	0.10	-0.43 (-0.55, -0.30)	3.97 × 10-11
cg21825879	FAT3	-0.05 (-0.11, -0.0001)	0.04	-0.001 (-0.05, 0.05)	0.83	0.003 (-0.04, 0.05)	0.99	-0.12 (-0.17, -0.07)	1.83 × 10-7
cg21990700	C1RL	-0.56 (-1.06, -0.07)	0.03	-0.40 (-0.91, 0.12)	0.13	-0.34 (-0.83, 0.15)	0.18	-1.13 (-1.56, -0.7)	2.97 × 10-7
cg14332918	PICK1	-0.08 (-0.18, 0.02)	0.10	-0.03 (-0.13, 0.08)	0.44	0.002 (-0.10, 0.10)	0.98	-0.23 (-0.32, -0.14)	1.56 × 10-7

Measures of glycemia were transformed to z-scores (mean = 0 and SD = 1) before the analysis to allow comparability in the effect estimates among traits. CpGs analyzed were identified in the epigenome-wide association study of second trimester maternal HbA1c (n = 412). Highlighted in bold are associations identified with p < 0.05 with one measure of glycemia.