Vitamin D deficiency and supplementation during pregnancy
Article first published online: 2 SEP 2008
© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd
Volume 70, Issue 5, pages 685–690, May 2009
How to Cite
Yu, C. K. H., Sykes, L., Sethi, M., Teoh, T. G. and Robinson, S. (2009), Vitamin D deficiency and supplementation during pregnancy. Clinical Endocrinology, 70: 685–690. doi: 10.1111/j.1365-2265.2008.03403.x
- Issue published online: 31 MAR 2009
- Article first published online: 2 SEP 2008
- (Received 14 March 2008; returned for revision 10 April 2008; finally revised 17 August 2008; accepted 19 August 2008)
Objective Vitamin D is essential for skeletal health and prolonged deficiency results in infantile rickets and adult osteomalacia. The aim of this study is to determine the vitamin D status in pregnancy and to evaluate the effects of daily and of single-dose vitamin D supplementation.
Design A prospective randomized study at St Mary's Hospital London.
Patients A total of 180 women (Indian Asian, Middle Eastern, Black and Caucasian) were recruited at 27 weeks gestation and randomized into three treatment groups: a single oral dose of 200 000 IU vitamin D, a daily supplement of 800 IU vitamin D from 27 weeks until delivery and a no treatment group.
Measurements Vitamin D (25-hydroxyvitamin D), PTH and corrected calcium levels in mothers at 27 weeks and at delivery and cord 25-hydroxyvitamin D and corrected calcium levels.
Results The final maternal 25-hydroxyvitamin D levels were significantly higher in the supplemented group [daily dose (median) 42 (IQR 31–76) nmol/l, stat dose (median) 34 (IQR 30–46) nmol/l vs. median 27 (IQR 27–39) nmol/l in the no treatment; P < 0·0001] and significantly fewer women with secondary hyperparathyroidism in the supplemented group (10% in daily dose vs. 12% in stat dose vs. 27% in the no treatment; P < 0·05). Cord 25-hydroxyvitamin D levels were significantly higher with supplementation [daily dose median 26 (IQR 17–45) nmol/l, stat dose median 25 (IQR 18–34) nmol/l vs. median 17 (IQR 14–22) nmol/l in no treatment; P = 0·001].
Conclusion Single or daily dose improved 25-hydroxyvitamin D levels significantly. However, even with supplementation, only a small percentage of women and babies were vitamin D sufficient. Further research is required to determine the optimal timing and dosing of vitamin D in pregnancy.