ABSTRACT
To examine the effect of antenatal Dexamethazone administration on healthy preterm fetuses using fetal biophysical profile, vibroacoustic stimulation and umbilical artery Doppler indices. Prospective study. Department of Obstetrics and Gynecology, Faculty of Medicine, Cairo University 120 singleton pregnancies between the gestational ages of 30 and 34 weeks who received two consecutive doses of Dexamethasone 12 hours apart. Fetal biophysical profile, Vibroacoustic stimulation and Doppler measurement of the umbilical artery S/D and PI were performed at 0 [pre-steroid], 48, 96 hours after the administration of first dose. 109 of 120 fetuses [90.8%] displayed a startle response to vibroacoustic stimulation prior to Dexamethasone administration, in comparison to 37 of 120 fetuses [30.8%] at 48 hours after exposure [p<0.05]. At 48 hours after Dexamethazone administration, 83 fetuses [69.16%] displayed no startle response [p<0.05]. At 96 hours after Dexamethazone exposure, no significant differences in the number of fetuses with present or absent startle responses were observed in comparison to 0 hours. None of the Doppler indices was found to be affected by the steroid administration. Maternal Dexamethasone administration can cause a significant but transient, reduction in sonographically observed fetal startle response to vibroacoustic stimulation and biophysical profile scores, accordingly, these modalities cannot be used for the ascertainment of fetal well-being of steroid exposed fetuses. Doppler indices of the umbilical artery were found to be unaffected suggesting the reliability of this modality for the evaluation of the fetuses previously exposed to the antenatal steroids