The role of antenatal factors on tibial speed of sound values in newborn infants.

OBJECTIVE

To evaluate the role of some antenatal factors on bone status of newborn infants.

METHODS

Tibial bone speed of sound (SOS) value was measured by quantitative ultrasound within 5 days after birth in 205 neonates whose gestational ages ranged between 31 and 40 weeks. The cohort was divided into two groups according to intrauterine growth curves, as small- (SGA) and appropriate-for-gestational age (AGA). All cases were also been evaluated by antenatal ultrasonography for oligohydroamniosis.

RESULTS

The mean SOS value was found significantly higher in SGA (n = 43) than AGA infants (n = 162) (p < 0.001). The mean tibial SOS value of infants with a history of oligohydroamniosis (n = 28) was also higher than those without oligohydroamniosis (n = 177) (p < 0.001). But, in SGA infants with a history of oligohydroamniosis (n = 17), the mean tibial SOS value was similar to those SGA infants without oligohydroamniosis (n = 26) (p > 0.05). Infants whose mothers had smoked during pregnancy (n = 18) had significantly higher tibial SOS values compared to those of whose mothers had not (n = 187) (p = 0.006). In addition, mean tibial SOS values were determined higher in male infants (n = 116) compared to female infants (n = 89) (p = 0.036). There was a significant correlation between tibial SOS values and gestational age (r = 0.178, p = 0.011).

CONCLUSIONS

While creating reference curves of SOS values at birth, smallness for gestational age, maternal smoking and gender as well as gestational age should be taken into account.