Search results
Results From The WOW.Com Content Network
The embryo is surrounded by the thin membranes of the amniotic sac, the umbilical cord is seen in the center, attaching the embryo to the placenta. The umbilical cord develops from and contains remnants of the yolk sac and allantois. It forms by the fifth week of development, replacing the yolk sac as the source of nutrients for the embryo. [2]
In humans, the circulatory system is different before and after birth. The fetal circulation is composed of the placenta, umbilical blood vessels encapsulated by the umbilical cord, heart and systemic blood vessels. A major difference between the fetal circulation and postnatal circulation is that the lungs are not used during the fetal stage ...
Physiology: In utero, the placenta delivers oxygenated blood to the fetus through the umbilical vein. Upon delivery, the umbilical cord is cut. The cardiovascular system must now adapt. Blood CO 2 rises because it is now not removed by the placenta. This is a powerful stimulus for the infant to start breathing.
In velamentous cord insertion, the vessels of the umbilical cord are improperly inserted in the chorioamniotic membrane, and hence the vessels traverse between the amnion and the chorion towards the placenta. [1] [11] Without Wharton's jelly protecting the vessels, the exposed vessels are susceptible to compression and rupture. [1] [9]
The embryo is joined to the trophoblastic shell by a narrow connecting stalk that develops into the umbilical cord to attach the placenta to the embryo. [ 11 ] [ 15 ] Arteries in the decidua are remodelled to increase the maternal blood flow into the intervillous spaces of the placenta, allowing gas exchange and the transfer of nutrients to the ...
The baby was found swaddled in a towel inside a basket and breathing weakly with the umbilical cord still attached around 3 a.m. on Tuesday, Jan. 21, News 4 (WOAI) San Antonio reported on Jan 24.
Overt umbilical cord prolapse requires rupture of membranes. This is the most common type of cord prolapse. occult umbilical prolapse: descent of the umbilical cord alongside the presenting fetal part, but has not advanced past the presenting fetal part. Occult umbilical prolapse can occur with both intact or ruptured membranes.
The amnion is the innermost layer and, therefore, contacts the amniotic fluid, the fetus and the umbilical cord. [5] The internal pressure of the amniotic fluid causes the amnion to be passively attached to the chorion. [4] The chorion functions to separate the amnion from the maternal decidua and uterus. [4]