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.
Researchers at the University of Utah pioneered the procedure whereby a patient's own stem cells are injected into their left ventricle in an attempt to treat heart failure. At this point, they are called cardiac repair cells. They are derived from the patient's bone marrow and then cultured for just under fortnight, after which they are implanted into the heart. It turns out these cells are much hardier than the original cells that were harvested from the bone marrow.
The very first stem cells to be isolated came from mice in 1981. They were consequently harvested from humans in 1998. There are other sources of this material other than human embryos. For one thing, they may come from the bone marrow. They may also be isolated from peripheral blood or from neonatal umbilical cords.
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.
Researchers at the University of Utah pioneered the procedure whereby a patient's own stem cells are injected into their left ventricle in an attempt to treat heart failure. At this point, they are called cardiac repair cells. They are derived from the patient's bone marrow and then cultured for just under fortnight, after which they are implanted into the heart. It turns out these cells are much hardier than the original cells that were harvested from the bone marrow.
The very first stem cells to be isolated came from mice in 1981. They were consequently harvested from humans in 1998. There are other sources of this material other than human embryos. For one thing, they may come from the bone marrow. They may also be isolated from peripheral blood or from neonatal umbilical cords.
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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