Blood Pressure
It is the fetal heart and not the mother's heart that builds up the fetal blood pressure to drive its blood through the fetal circulation.
Intracardiac pressure remains identical between the right and left ventricles of the human foetus.
The blood pressure in the fetal aorta is approximately 30 mmHg at 20 weeks of gestation, and increases to ca 45 mmHg at 40 weeks of gestation. The fetal pulse pressure is ca 20 mmHg at 20 weeks of gestation, increasing to ca 30 mmHg at 40 weeks of gestation.
The blood pressure decreases when passing through the placenta. In the arteria umbilicalis, it is ca 50 mmHg. It falls to 30 mmHg in the capillaries in the villi. Subsequently, the pressure is 20 mm Hg in the umbilical vein, returning to the heart.
Read more about this topic: Fetal Circulation
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