The effect of antenatal steroid treatment for premature lung maturation on the fetal autonomous nervous system revealed by fetal magnetocardiography (fMCG)

Abstract

Objective: Steroid administration prior to 34 gestational weeks to accelerate fetal lung maturation reduces neonatal morbidity and mortality in the case of preterm delivery. In the animal model, a reduction in beat-to-beat-variability of the fetal heart rate (fHRV) under steroid administration has been documented [1]. These observations are in accordance with the clinical experience of reduced biophysical activities of the human fetus. Aside from gestational age, fetal state is the major influencing factor on fHRV [2]. We test the hypothesis that both linear fHRV and complexity reflect the influence of betamethasone if the fetal state is considered.