Calcium supplementation during pregnancy improves tibial bone density at one year post‐partum in racially diverse women (250.3)

Abstract

Low calcium intakes during pregnancy may mobilize the maternal skeletal calcium to meet fetal needs. The objective of this study was to determine the effect of maternal calcium supplementation on peripheral cortical and trabecular bone loss during pregnancy (PG) and gain postpartum (PP). Sixty‐four women (21 African American, 20 Caucasian, 10 Hispanic, 9 Asian, 4 Other) were enrolled in the study at 16 weeks gestation and randomized to 1000 mg of calcium/day (CA) or placebo during PG. Measurements were done at 16, 26 and 36 weeks of PG and 4 and 12 months PP for osteocalcin (OST), c‐peptide of type 1 procollagen (CICP), or c‐terminal telopeptide (CTx). Trabecular and cortical bone mineral density (BMD) and content were assessed at the tibia by peripheral quantitative computed tomography. 80% of subjects have completed the study to date. Calcium intake averaged 906±596 mg /day at baseline. There was a significant difference between CA and Placebo in OST, p=0.025; CICP, p=0.012 and CTx, p=0.008 in PP time points. Using intention to treat analysis, and general linear models for longitudinal data, adjusting for baseline, the CA group had significantly greater increases in total BMD at the 4 and 12 mo PP visits (p=0.043), and a trend towards an increase in trabecular BMD (p=0.064) at 12 mo PP, compared to Placebo. These data suggest that supplemental calcium during pregnancy may improve BMD recovery in the postpartum period.Grant Funding Source: USDA #UL1RR024131