In vitro fertilization is a procedure that childless couples may use when they are having trouble conceiving the natural way. It is the next step after artificial insemination has failed to yield the desired result. The IVF procedure involves fertilization of the woman's eggs in a petri dish and then implanting the resulting embryos. Unused embryos are a byproduct of this process. There are a number of different ways of dealing with these and it is the responsibility of the parents to determine what happens to them.
After fertilization has taken place, the extra embryos are frozen and stored. Today's techniques for freezing this tissue enable these tissues to retain their viability for a matter of years. The parents can decide to leave them in storage, donate them for medical research, hand them over to other couples who are having difficulty conceiving by any other means, or they may keep storing them until they decide their fate or elect to have them sent for destruction.
Stem cells are highly primitive cells that have the ability to differentiate into all other cell types in the body. This is what is meant by the term, "pluripotent." Stem cells are turning out to be incredibly useful for medical purposes, although they are very tightly regulated because of their potential for abuse.
Scientists at the University of Utah were the first to inject stem cells into the left ventricles of patients to treat heart failure. Cardiac repair cells were drawn from the patients' own bone marrow and placed into culture for around 12 days. The cells that survived in culture turned out to be stronger than the patient's original cells and were injected into the left ventricles of the patients' hearts.
The first time stem cells were isolated from mice was in 1981; in humans, it was 1998. These cells may arise from spare human embryos that did not need to be implanted. Other places where stem cells come from include peripheral blood, umbilical cords and bone marrow. Other conditions apart from heart failure where stem cells have been used include diabetes, neurological problems and cancer.
Bone marrow is located deep inside the large bones of the body; specifically, the pelvic bone. Getting to these cells is a highly painful procedure so it is commonly accomplished with the use of a general anesthetic. Then, a large-bore needle is used to draw the cells via the hip bone.
Peripheral blood is not normally a rich source of stem cells. However, when donors are given hormones called growth factors a few days before the harvest increases their cell numbers. This process can take several hours. The blood of newborn babies is rich in stem cells. Those left in the umbilical cord are harvested and frozen for future transplantation. So far, umbilical cord cell transplants have only been conducted in children and small adults.
Once the parents are sure they do not want any more children, there are a number of things they can decide to do with the extra embryos. They may donate them for research, discard them or allow them to be passed on to other childless couples who are unable to conceive by other methods.
After fertilization has taken place, the extra embryos are frozen and stored. Today's techniques for freezing this tissue enable these tissues to retain their viability for a matter of years. The parents can decide to leave them in storage, donate them for medical research, hand them over to other couples who are having difficulty conceiving by any other means, or they may keep storing them until they decide their fate or elect to have them sent for destruction.
Stem cells are highly primitive cells that have the ability to differentiate into all other cell types in the body. This is what is meant by the term, "pluripotent." Stem cells are turning out to be incredibly useful for medical purposes, although they are very tightly regulated because of their potential for abuse.
Scientists at the University of Utah were the first to inject stem cells into the left ventricles of patients to treat heart failure. Cardiac repair cells were drawn from the patients' own bone marrow and placed into culture for around 12 days. The cells that survived in culture turned out to be stronger than the patient's original cells and were injected into the left ventricles of the patients' hearts.
The first time stem cells were isolated from mice was in 1981; in humans, it was 1998. These cells may arise from spare human embryos that did not need to be implanted. Other places where stem cells come from include peripheral blood, umbilical cords and bone marrow. Other conditions apart from heart failure where stem cells have been used include diabetes, neurological problems and cancer.
Bone marrow is located deep inside the large bones of the body; specifically, the pelvic bone. Getting to these cells is a highly painful procedure so it is commonly accomplished with the use of a general anesthetic. Then, a large-bore needle is used to draw the cells via the hip bone.
Peripheral blood is not normally a rich source of stem cells. However, when donors are given hormones called growth factors a few days before the harvest increases their cell numbers. This process can take several hours. The blood of newborn babies is rich in stem cells. Those left in the umbilical cord are harvested and frozen for future transplantation. So far, umbilical cord cell transplants have only been conducted in children and small adults.
Once the parents are sure they do not want any more children, there are a number of things they can decide to do with the extra embryos. They may donate them for research, discard them or allow them to be passed on to other childless couples who are unable to conceive by other methods.
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