Bone speed of sound in infants of mothers with gestational diabetes mellitus

Objective: Bone strength in infants of mothers with gestational diabetes mellitus (IGDM) was reported to be either decreased or unaltered. However, no report using quantitative ultrasound measurement of speed of sound (QUS-SOS) for bone strength assessment has been published. The aim of the present study was to assess bone strength by QUS-SOS measurements in IGDM in comparison to healthy matched full-term infants. Design: Nineteen IGDM and 18 healthy controls participated in the study. Postnatal tibial bone SOS was measured by Sunlight Omnisense™. Results: Mean birth weight (BW) of IGDM (3,587.6 ± 148.6 g) was higher compared to the control infants (3,311.1 ± 74.5 g), but this difference was not statistically significant. Mean bone SOS was significantly lower in IGDM (2,976.7 ± 27.2 m/sec) compared to the control infants (3,093.3 ± 23.6 m/sec; p <0.003). There was a significant negative correlation between bone SOS and BW in all the study participants (r = -0.32, p <0.025). No significant difference in BW and bone SOS was noted between infants with postnatal hypoglycemia and normoglycemia. There was no correlation between maternal HbA_1c during pregnancy and neonatal bone SOS. Conclusions: Bone strength was significantly decreased in IGDM compared to healthy controls. Neonates with higher BW had lower bone SOS. Since mechanical strain is a potent stimulation for bone formation and strength, it is suggested that the reduced bone strength in IGDM may also be the result of reduced intra-uterine fetal mobility due to maternal gestational diabetes mellitus.