placental circulation การใช้

• A cord prolapse is an obstetrical emergency, as the descending head may block fetal-placental circulation.
• Dr . Ramsey, with Martin Donner, assembled a body of work that illuminated many key features of placental circulation.
• Another cause factor is determined to be monochorionic twin pregnancies, involving the death of one twin in the second trimester, which in turn causes vascular exchange to the living twin through placental circulation through twin-to-twin transfusion, causing hydranencephaly in the surviving fetus.
• The umbilical and placental circulation system differs from the regular circulation in that veins, not arteries, carry the oxygenated blood to the fetus, and arteries, not veins, carry away the oxygen-depleted blood, with the waste products, back to rejoin the mother's blood supply.
• Maternal tissue only plays a role in support ( the maternal decidua basalis is the supportive structure to which the fetal placental component attaches ) and in placental circulation ( the spiral arteries of the maternal endometrium penetrate the developing chorionic villi and bathe the fetal tissue in maternal blood ).
• At birth, when the placental circulation ceases, the pelvic portion only of the umbilical artery remains patent gives rise to the superior vesical artery ( or arteries ) of the adult; the remainder of the vessel is converted into a solid fibrous cord, the medial umbilical ligament ( otherwise known as the obliterated hypogastric artery ) which extends from the pelvis to the umbilicus.