BACKGROUND:Fetal heart rate variability (fHRV) of normal-to-normal (NN) beat intervals provides high-temporal resolution access to assess the functioning of the autonomic nervous system (ANS). AIM:To determine critical periods of fetal autonomic maturation. The developmental pace is hypothesized to change with gestational age (GA). https://parisnaturalfoodes.shop/product-category/slippery-elm/