Bone mineral changes during pregnancy: a cross-sectional study

Ritu Sharma, Deepali Garg, Huma Khan


Background: Changes in bone mineral density during pregnancy are not widely studied because of the risk of radiation hazard to the fetus. But newer technology like DEXA has made it possible to measure bone density accurately with low dose radiations which are safe even during pregnancy. The aim of this study was to evaluate the changes in maternal bone turnover markers and bone mineral content at forearm during pregnancy.

Methods: A total of 32 pregnant women with singleton pregnancy of more than thirty five weeks gestational age and thirty non-pregnant, non-lactating women as controls were recruited. Baseline blood investigations, serum calcium, serum alkaline phosphatase and DEXA of the forearm at ultra-distal, mid radius and proximal 1/3rd of radius were done at the time of recruitment into the study.

Results: Bone mineral density of forearm of pregnancy group was compared with non-pregnant, non-lactating control group to see the effect of pregnancy. Bone turnover markers like serum calcium and serum ALP were also compared among pregnancy group and controls. The mean bone mineral density of controls at ultra-distal radius was 0.437±0.058g/cm2, while in pregnant women it was 0.431±0.58g/cm2 that was not statistically significant. Bone mineral density at mid radius in control was 0.599±0.051g/cm2 and in pregnant women it was 0.597±0.048 g/cm2 with no significant difference. BMD at proximal 1/3rd radius in controls was 0.670±0.36 g/cm2 as compared to pregnant women where it was 0.660±0.036 g/cm2 without any statistical significance. Total BMD at forearm in control and pregnant women was 0.586±0.035 and 0.582±0.036 respectively and again there was no statistically significant difference.

Conclusions: There is no significant impact of pregnancy on bone mineral density of forearm. Although more bone areas need to be investigated for the further confirmation.


Bone mineral density, DEXA, Forearm, Pregnancy, Radius

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