The influence of direct intramuscular corticosteroid therapy on parameters of venous circulation in hypoxaemic fetuses

Introduction: The influence of glucocorticosteroid therapy on fetal lung maturation is evident but little is known about its effects on parameters of fetal venous circulation. Objective. The aim of the study was to assess the influence of direct intramuscular (i.m.) fetal corticosteroid therapy (CST) on parameters of fetal venous circulation which indicates a degree of fetal hypoxia. Method. The prospective study was conducted at the Institute of Gynaecology and Obstetrics during 2001. We evaluated the influence of direct i.m. fetal single dose dexamethasone (2 mg/ kg estimated fetal weight by sonographic examination) on foetal ductus venosus (DV) and vena cava inferior (VCI) velocities in 49 fetuses 24 hours before and after therapy. Results. There is positive correlation with the statistical significance in systolic/diastolic ratio (S/D) in DV before and after the corticotherapy r=0.366; p=0.018. Reverse flow during contraction of the right atrium in DV was found in 55.6% of fetuses after CST. Reverse flow during the contraction of the right atrium in VCI was found in 3 fetuses before CST and in 4 fetuses after CST. We found positive correlation without statistical significance between the vena cava pre-load indices before and after CST (r=0.127; p= 0.428). There is positive correlation with the statistical significance between systolic flow in VCI before and after CST (r=0.478; p=0.002). Conclusion. Corticosteroid therapy influences parameters of fetal venous circulation. Its influence depends on duration of fetal hypoxia. The parameters of fetal venous circulation can be a predictor of the perinatal outcome.