The placenta plays a crucial role in the growth, development and survival of the baby. The placenta is formed with trophoblastic cells; these cells grow through the walls of the mother's blood cells. Fetal circulation is separate from the mother's circulation but the blood flow from the fetus in the placenta is close to the mother's blood flow. Placenta growth is rapid; at 10 weeks the placenta weighed about 20g and grows to weigh about 650g at full term. The connection between the fetus' cells and the placenta begin at the 2nd and 3rd week of development and around this time, the villi at the bottom of the placenta attaches to the bottom layer of the uterus. Villi have a very important function - it absorbs nutrients and oxygen from the mother's blood and this is in turn transported to the baby through the umbilical cord.







Baby's waste is transferred from the umbilical arteries to the maternal bloodstream. Placenta is responsible for transporting oxygen and carbon dioxide to and from the baby. It is also involved in the supply of nutrients and removal of excreta from the baby. Placenta is responsible in the production of important hormones; HCG, a hormone that will determine your pregnancy after a pregnancy test is produced by the placenta. It also produces the hormones estrogen and progesterone at the 8th week of pregnancy. It is flat and cake like in appearance, either round or oval in shape. However its shape and size varies widely. It is red or reddish brown in tone. It is about 2-3cm thick at the thickest part and weighs about 500-650g on average. Around the time of birth it may have white patches on it - these are calcium deposits. If you are carrying more than one fetus, there may be more than one placenta playing its role or there may be one placenta with more than one umbilical cord attached to it. Usually there are 2 separate sacs for twins with 2 cords attached to the fetuses from one placenta. The umbilical cord which attaches the baby to the placenta is about 22 inches or 55cm long and it is usually white in color. It carries blood to and from the baby. Problems linked to placenta include placental abruption and placenta previa, both serious complications. After delivery, a retained placenta can become a problem.