32 weeks §The fetus became baby like §The head was proportional to the body
36 weeks §The skin became pink in color §The body became fat since fat was accumulated in the body §The hair was about 5cm long
40 weeks §The body looked fat §The fetus may hurt himself by his fingers
Exchange of nutrient and waste Since every person has to eat so as to survive and have to secrete all the wastes from their body. For a fetus, the chorionic will present a large area for the exchange of material and fetal blood flow in opposite direction. This counter-current flow leads to more efficient exchange. Oxygen, water, amino acid, glucose, essential minerals, etc. are transferred from material to fetal blood to nourish the developing fetus. Carbon dioxide, urea and other wastes are transferred from fetal to maternal blood to allow their excretion by the mother and prevent harmful accumulation in the fetus. It also allows certain maternal antibodies to pass into the fetus, providing it with some immunity against disease.
Labor and delivery §After 40 weeks, it was time for the baby to come out. Every pregnant woman should be familiar with three definite signs that delivery is imminent: regular contractions, ruptured membranes (‘waters breaking’) and a ‘show’ of mucus sometimes mixed with blood. §Uterine contractions are felt by most women at odd times throughout the last weeks of pregnancy. There isolated contractions cause the uterus to become as hard as a ball for one or more minutes. As delivery approaches, these contractions become strong and increasingly regular.
§Contractions at intervals of less than ten minutes are fairly reliable indication that labor has begun. These contractions have been called ‘labor pains’ since time immemorial, since they are-ate a later stage, though generally not initially-associated with pain. If the woman is upright, she stops and braces herself during the contractions, perhaps leaning against a chair or a wall. When the contractions are occurring about every five minutes, it is normally time for admission to the hospital. If the woman feels unsure, the best course of action is to call the doctor or midwife.
§Labor sometimes begins with amniotic sac (‘bag of waters’) has ruptured. Before labor starts or in the first stage, the plug of mucus in the cervix loosens and passes out of the vagina. This plug is often slightly mixed with blood and may have loosened in conjunction with negligible contractions that the woman has not even felt. It was time for the baby to come out. §The umbilical cord is cut immediately after birth, although the placenta remains in the uterus, where it gradually begins to come loose. In the third and final stage of labor, the mother must bear down for the last time, and the placenta is expelled. The uterus can now contract, gradually returning to its original size.
§From the above, we have taught about how a baby came out from his mother’s body. If you want to see a more real pictures of this. We can take out the video tape we provided. It will introduce to you the process of fertilization and explains how the fertilized cell develops into an embryo. You can also observe the development of the embryo into a fetus. §Then, in the next part, we will tell you some cases which lead to a baby cannot be born. You can move on to our handouts. ~ END ~