Concurrent calcium and vitamin D supplementation during pregnancy increases bone density in adolescent mothers: a randomized, placebo-controlled trial
Based on study:
“Effect of calcium plus vitamin D supplementation during pregnancy in Brazilian adolescent mothers: a randomized, placebo-controlled trial”
Maria Eduarda L Diogenes, Flávia F Bezerra, Elaine P Rezende, Marcia Fernanda Taveira, Isabel Pinhal and Carmen M Donagelo
The American Journal of Clinical Nutrition (2013)
98(1):82-91
July
Summary:
Calcium demand increases during pregnancy and lactation periods, especially in young mothers. Vitamin D is important for calcium absorption and to boost bone metabolism and must be administered concurrently with calcium supplements. This randomized, placebo-controlled trial was conducted to investigate the influence of calcium plus vitamin D supplementation during the last trimester of pregnancy on bone mass and bone and calcium related hormones during lactation, in Brazilian adolescent mothers who consume low-calcium diets. The findings of this study show that taking calcium plus vitamin D supplements during pregnancy results in higher lumbar spine bone mass and a reduced rate of femoral neck bone loss during lactation. Therefore, concurrent supplementation of these two nutrients during pregnancy is highly recommended for adolescent mothers.
Key words:
Bone mass, calcium, femoral neck bone loss, gestation, lactation, lumbar spine, postpartum, vitamin D
Calcium demand increases during pregnancy and lactation to transfer adequate amounts to the growing fetal skeleton and for breast-milk production. In young mothers with low calcium intake, maternal bone mass could be negatively affected. In comparison to their adult counterparts, adolescent mothers have greater bone loss, lower bone mineral content (BMC) and bone mineral density (BMD). Thus far, there have been no studies to test if a supplement-induced calcium increase during pregnancy could be protective against bone mass reduction during lactation in adolescent mothers. Because vitamin D is important for calcium absorption and to boost bone metabolism, vitamin D must be administered concurrently with calcium supplements. Therefore, this study was conducted to investigate the influence of calcium plus vitamin D supplementation during the last trimester of pregnancy on bone mass, content and density, and calcium related hormones during lactation, in Brazilian adolescent mothers who consume low-calcium diets.
Pregnant adolescents, aged 14-19y, were chosen randomly to receive daily calcium (600 mg) plus vitamin D3 (200 IU) or a placebo (n = 26) from 26 weeks of pregnancy until parturition. The BMC, bone area (BA) and BMD at the total body, lumbar spine and hip were evaluated at 5 and 20 weeks postpartum. Serum hormones and 25-hydroxyvitamin D [25(OH)D] were measured. Mean chronologic age and time elapsed since the onset of menarche was 17.0 and 5.3 y, respectively. The body mass index was within the normal range. There were no significant differences in body weight and height between the 2 groups at 5 and 20 week postpartum. The mean serum 25(OH)D concentration was 59 nmol/L at baseline. When compared with the placebo, 25(OH)D tended to be 14-15 nmol/L higher postpartum in the supplemented group (P = 0.08). Total body and hip BMC and BMD decreased over time (P ≤ 0.005) in both groups. Supplemented mothers had higher lumbar spine BA (P = 0.002) and lumbar spine BMC (P = 0.08) than did mothers who consumed the placebo at 5 week postpartum. Differences between groups were more evident at 20 week postpartum, with higher lumbar spine BMC, BA and BMD in the supplemented group (P ≤ 0.008).
In conclusion, it is highly recommended that adolescent mothers with low calcium intakes should take calcium plus vitamin D supplements during pregnancy. This is likely to result in higher lumbar spine bone mass and a reduced rate of femoral neck bone loss during lactation.
In a randomized, placebo-controlled trial, pregnant adolescents received either daily calcium (600 mg) plus vitamin D3 (200 IU) or a placebo. Researchers concluded that concurrent calcium and vitamin D supplementation during pregnancy resulted in higher bone mass and a reduced rate of bone loss during lactation. Therefore, concurrent calcium and vitamin D supplements during pregnancy are highly recommended for adolescent mothers.