Table 3.

Differences in bone biomarker concentrations between each vitamin D group and placebo group among pregnant women at delivery.

	Intervention group (prenatal vitamin D dose, IU/week)a
	N	B (4200)	Pb	C (16800)	Pb	D + E (28000)	Pb
		Percent difference (95 % CI)		Percent difference (95 % CI)		Percent difference (95 % CI)
OPG	564	−0.46 (−12,12)	0.938	−8.6 (−19, 2.5)	0.123	−0.26 (−10,10)	0.961
OPG/RANKL	564	−20 (−42, 9.7)	0.164	−7.5 (−32, 26)	0.625	−5.0 (−28, 25)	0.718
P1NP	565	1.2 (−14, 20)	0.89	6.0 (−10, 25)	0.486	−7.8 (−20, 6.6)	0.271
OC	562	−1.6 (−12,11)	0.787	−4.3 (−15, 7.2)	0.449	−4.0 (−13, 6.2)	0.430
RANKLc	566	32 (−6.2, 86)	0.111	2.9 (−26, 44)	0.867	9.9 (−18, 48)	0.535
FGF23c	647	−9.1 (−26, 11)	0.356	6.2 (−13, 29)	0.544	−7.0 (−21,10)	0.400
CTxd	226	–	–	–	–	−27 (−38, −13)	<0.001

^aGroups D and E are combined in these analyses since they were identical in prenatal dose with the exception of CTx, which is presented for group E only.

^bP-value of mean difference in each intervention group versus placebo, adjusting for enrollment (second trimester) biomarker concentration (except P1NP, due to unavailability of enrollment P1NP data).

^cTobit regression to account for left censoring of RANKL distributions and right censoring of FGF23 distribution.

^dThe effect of vitamin D on CTx concentration is shown for group E versus group A; see supplementary methods for explanation.