Later Development, Develop. Physiol., Dr. D. Penney

Table 3.03 - Effects of Hypoxia.

In the Fetus:

• lowers PO₂ in umbilical vessels, increasing diffusion gradient; Hb O₂ saturation falls

• PCO₂ raised; pH lowered

• use of glycolytic pathway increased; lactate produced

• umbilical blood flow increased

• bradycardia

• blood pressure increased

• plasma titers of epinephrine and norepinephrine increased sharply

• blood flow redistributed mainly to brain, heart and placenta

• O₂ consumption decreased; "oxygen sparing"

• polycythemia (chronic response)

• body growth retardation (chronic response)

In the Mother:

• uterine blood flow increased

• hyperventilation increased; decreased maternal and fetal PCO₂ and increased gradient at placenta

Return to Page 5