The Physiology of Intrapartum Fetal Compromise at Term

Uterine contractions in labor result in a 60% reduction in uteroplacental perfusion, causing transient fetal and placental hypoxia. A healthy term fetus with a normally developed placenta is able to accommodate this transient hypoxia by activation of the peripheral chemoreflex, resulting in a reduction in oxygen consumption and a centralisation of oxygenated blood to critical organs, namely the heart, brain and adrenals. Providing there is adequate time for placental and fetal re-perfusion between contractions, these fetuses will be able to withstand prolonged periods of intermittent hypoxia and avoid severe hypoxic injury.

Source: American Journal of Obstetrics and Gynecology - July 23, 2019 Category: OBGYN Authors: Jessica M. Turner, Murray D. Mitchell, Sailesh Kumar Tags: Expert Review Source Type: research