Biomaterial Database

Mechanisms of placentofetal blood flow. 1978

S R Reynolds

The average length of the umbilical cord at delivery is 21 +/- 1 in., but lengths vary from 10 to 50 in. When distended and carrying blood between the fetus and the placenta, the cord is longer; the distended areteries and vein are spiraled about each other. No physiologic data explain the manner by which blood flows from the placenta to fetus. When pressures (60-80 mmHg in arteries 10-20 mmHg in the vein) are recorded simultaneously, arterial pulse pressure has been observed to rise and umbilical vein pressure to fall. They are 180 degrees out of phase. When necessary physical factors are taken into account, it is found that the system satisfies all requirements of a pump known as one of the pulsometer type. This system is one that is widely used by engineers, but it is unique among physiologic systems.

UI	MeSH Term	Description	Entries
D010920	Placenta	A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).	Placentoma, Normal,Placentome,Placentas,Placentomes
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D012039	Regional Blood Flow	The flow of BLOOD through or around an organ or region of the body.	Blood Flow, Regional,Blood Flows, Regional,Flow, Regional Blood,Flows, Regional Blood,Regional Blood Flows
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D005260	Female		Females
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, Fetal
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014469	Umbilical Arteries	Specialized arterial vessels in the umbilical cord. They carry waste and deoxygenated blood from the FETUS to the mother via the PLACENTA. In humans, there are usually two umbilical arteries but sometimes one.	Arteries, Umbilical,Artery, Umbilical,Umbilical Artery
D014471	Umbilical Veins	Venous vessels in the umbilical cord. They carry oxygenated, nutrient-rich blood from the mother to the FETUS via the PLACENTA. In humans, there is normally one umbilical vein.	Umbilical Vein,Vein, Umbilical,Veins, Umbilical
D014690	Venous Pressure	The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.	Blood Pressure, Venous,Blood Pressures, Venous,Pressure, Venous,Pressure, Venous Blood,Pressures, Venous,Pressures, Venous Blood,Venous Blood Pressure,Venous Blood Pressures,Venous Pressures