Effect of Antenatal Dexamethasone Administration on Foetal and Uteroplacental Doppler Waveforms in Women at Risk of Spontaneous Preterm Birth: A Prospective Study

ABSTRACT

Introduction: The effects of antenatal dexamethasone onfoetal and uteroplacental circulation as measured by Dopplerwaveform has gained more attention recently. In the presentstudy, we aimed to assess the change in foetal anduteroplacental circulation following antenatal dexamethasoneadministration to high-risk pregnant women.Methods: We conducted a prospective cohort study on 50pregnant women with high risk of preterm birth within thegestational age from 24 to 34 weeks. Two doses ofdexamethasone was administrated and. Doppler velocitywaveforms were obtained from the umbilical artery, fetal middlecerebral artery (MCA), fetal descending aorta and maternaluterine arteries Data analysis was carried out using SPSSversion 22 for Microsoft Windows.Results: The mean age of the included women were 27.9 ±4.8years while the mean parity was 2.14 ±1.4. Eighty percent ofthe children were alive at delivery. In terms of Doppler Indices,the umbilical artery pulsatility index (PI) and resistive indexshowed a statistically significant reduction afterDexamethasone administration (p <0.001). Similarly, theuterine and MCA arteries PI and RI showed a statisticallysignificant reduction after Dexamethasone administration (p<0.001). In terms of Cerebro-umbilical ratio (CUR), the ratioshowed a statistically significant increase after Dexamethasoneadministration (p =0.015). The CUR increased significantlyafter dexamethasone administration to reach 2.1 ±0.33. Onlyone patient had abnormal velicometry before and afterdexamethasone.Conclusion: In conclusion, the present study shows thatantenatal dexamethasone administration significantly improvethe fetal and uteroplacental hemodynamics, assessed byDoppler, among women with risk of preterm labor