How long does it take for the fetus to die due to lack of oxygen?

Women often experience many symptoms when they are pregnant, especially the fetus in the belly. They may experience some dangerous situations due to various reasons, such as malposition of the fetus, etc., including fetal hypoxia, which may lead to fetal death. After all, people will die without oxygen, and the same is true for the fetus. So how long will it take for the fetus to die due to fetal hypoxia?

When the fetus shows signs of hypoxia in the uterus, which endangers the health and life of the fetus, it is called fetal distress. Fetal distress is a complex symptom and is currently one of the main indications for cesarean section. Fetal distress mainly occurs during labor, but can also occur in late pregnancy. Those that occur during labor may be a continuation and aggravation of those that occur in late pregnancy. Fetal distress is common in the prenatal period, mainly manifested by placental insufficiency. Pathophysiological high-risk pregnancies, such as gestational hypertension, chronic hypertension, nephritis, diabetes, heart disease, asthma, severe anemia, and overdue pregnancy, may result from vascular disease that reduces uterine blood flow, placental degeneration, or low blood oxygen concentration, which prevents the fetus from getting enough oxygen, leading to fetal growth retardation, polycythemia, decreased fetal movement, or even severe fetal distress, leading to fetal death.

Fetal distress mainly occurs during labor, but can also occur in late pregnancy. Those that occur during labor may be a continuation and aggravation of those that occur in late pregnancy. Fetal distress is common in the prenatal period, mainly manifested by placental insufficiency. Fetal death mainly refers to pathophysiological high-risk pregnancy, such as gestational hypertension, chronic hypertension, nephritis, diabetes, heart disease, asthma, severe anemia, overdue pregnancy, etc., or due to vascular disease that reduces uterine blood flow, or due to placental degeneration, or due to low blood oxygen concentration, the fetus cannot get enough oxygen, causing fetal growth retardation, polycythemia, decreased fetal movement, and even severe fetal distress, causing fetal intrauterine death.

Fetal distress and birth asphyxia are both important causes of perinatal death and neurological sequelae, accounting for the leading cause of perinatal death. When the fetus has mild ischemia or early ischemia, the main manifestations are vasodilation of important organs such as the heart, brain, and adrenal glands, and contraction of peripheral blood vessels such as the liver, kidneys, intestines and limbs to ensure the normal function of important vital organs; when the fetus is in a state of hypoxia for a long time, the ischemia is further aggravated and heart failure occurs. Coupled with the secretion of local vasoactive substances, the blood flow to all organs decreases. At this time, the fetus is in an irreversible damage stage, which endangers the life of the perinatal baby and can even lead to the death of the newborn in severe cases.