For most of us, our connection to an umbilical cord lasts only during our first few seconds of life.
However, for a growing number of people, umbilical cords represent a crucial lifeline even in adulthood.
Take Rhonda Kottke, for instance. On Dec. 28, 2001, at the age of 29, her doctor diagnosed the Chicago woman with leukemia.
Her treatments ravaged her immune system to the extent that if it were not replaced, she would die.
Kottke's siblings were tested, but their bone marrow was not a close enough match to hers. It was then that her doctors suggested a different course of treatment altogether -- an infusion of stem cells obtained from an umbilical cord.
The transplant came six months after her diagnosis. Today, doctors say the graft likely saved Kottke's life.
"I'm doing great, knock on wood," she told ABC's "Good Morning America." "I have no signs of leukemia in my blood. I have no sign of cancer at all. I'm as healthy as anyone else."
Kottke received her transplant from a public cord cell bank. However, many private companies offer new parents the chance to freeze their child's cord cells for personal use -- that is, if the child or a family member needs them.
But as the trend of banking cord blood continues to grow, critics say those who bank umbilical cord cells at private banks will most likely never use it.
And with an initial price tag of more than $1,000 to store the cord blood -- and yearly storage fees in the hundreds of dollars -- the cost of this biological insurance policy may outweigh the actual benefits for most.
At birth, the umbilical cord is normally thrown away. But in the past few years, doctors have discovered that it is chock full of stem cells, which can be used to treat as many as 70 different diseases.
Treatments using cord blood cells are still relatively new; so far, only about 6,000 Americans have received cord blood transplants. Most commonly, the cells are used to regenerate the immune systems of patients who have received treatment for leukemia.
"Cord blood is an increasingly valuable alternative to bone marrow transplant," says Dr. Curt Freed, head of clinical pharmacology and toxicology at the University of Colorado School of Medicine.
However, researchers say that future applications could be far broader. But, though cord blood treatments appear promising, much of the science surrounding these treatments is still speculative.
"There may be technology developed in the future that allow patients and parents to find it useful in a clinical setting, but there is a lot of science needing to be performed before any of this stem cell hype becomes reality," says Bryon Petersen, associate professor of pathology at the University of Florida.
Joshua D'Eramo's parents privately stored his umbilical cord blood when he was born. It was an expensive decision -- they paid their company $1,200 up front and $100 each year to store it.
"It's like an insurance policy," says his mother, Rena. "We get insurance for our cars, for a car accident and we may never need it, but it is comforting to know it is there if you do need it."
Today there are 25 private companies that will store a baby's cord blood for a fee. Like a bank account, it will be available exclusively to the family of the donor.
But the chances that anyone will ever need to make a withdrawal from such an "account" may be slim.
"There's nothing particularly wrong with doing that, but it's not very useful," says Dr. Cladd Stevens, medical director for the New York Blood Center's National Cord Blood Program.
"I think most of the professional organizations, the pediatric society and obstetric society, recognize that it's not very useful."
"A single individual has about a one-in-one-thousand chance of needing a bone marrow transplant in his or her lifetime, so banking does not make much sense as an insurance policy," Freed says. But, he adds, "In individual cases, such as a family member's illness that might be treated with cord blood, retaining cord blood could make sense."
Critics go one step further, saying that advertisements used by such private banks prey on the fears of new parents.
"I'm sure there are a certain amount of businesses and people with less than admirable scruples who take advantage of the public fears," Petersen says. "Those companies would blacken the eye of the business as a whole."
"Some private companies do push the idea that this is biological insurance," Stevens says. "That's the main selling point for private banks, but the real question is whether or not that ever pans out in reality."
However, for a select few families, private cord cell banking could prove to be much more useful.
"There is one circumstance in which cord blood ought to be stored for a family member, and that is when we know in advance that there's a family member that's already been affected -- an older child with leukemia, for example, or a genetic disease," Stevens says.
Parents who choose not to seek the services of a private bank have another option as well -- they can donate the cord cells to a public bank, which will, in turn, donate them to those in need.
"We initially thought about private banking, and I think most parents that think about it probably do, because your first thought is 'oh, my God, what happens if something happens to my baby?'" says 35-year-old new mother Angie Bongaarts of Chicago.
But Bongaarts and her husband discussed the matter, and together they agreed that since they had no family history of leukemia, they would, instead, send their daughter's umbilical cord to a public bank.
"We figured that there was probably a better chance for the blood going for use for someone who did have a problem right now," she says.
Two-and-a-half months after they donated their baby's cord blood to a public bank, Bongaarts and her husband were notified that the cells were used to help a young man with an immune problem.
Bongaarts says the prospect that her daughter's cells may have saved someone's life was a special gift.
"I was euphoric," she says. "It's been nice to think back on for the past couple weeks, to know that we were able to do that for someone."
According to Stevens, Bongaarts' story is not unique.
"We estimate there are probably 10,000 patients around the world who have benefited from the fact that a mother donated her baby's cord blood for anybody who needed it," she says.
"There are people who are alive now who otherwise would've been dead if there hadn't been a mother who donated their cord blood."
Largely due to the success stories seen thus far with public cord cell banking, many experts say a fully stocked national registry of 150,000 samples -- a project currently in development -- could save many lives.
"With medical research progressing -- and if everyone donates cord blood to public banks -- then an excellent cell match should be available for those that need cell transplantation in the future," Freed says.
Public banking saved Kottke's life. And she says the impacts of the lifeline she received are overwhelming.
"It's absolutely the most amazing thing anyone has ever done for me," Kottke says. "I'm thankful every day."
For more information about donations, visit www.nationalcordbloodprogram.org