Dear Judy, L.A. Times Reporter,
I enjoyed reading your article “Health Sense: Success rate elusive on Frozen Eggs ” Health Section LA Times; August 16, 2010, but clarification is definitely needed.
Human eggs are fragile whether they are freshly harvested or frozen and thawed. They are large, water filled cells that require a meticulous preparation before freezing and subsequent thawing.
Among the limiting rate factors found in older freezing protocols was that they did not sufficiently dehydrate the internal cellular fluid prior to subjecting the egg cell to cooling. Improvements at our center have yielded survival rates of 91% with 86% of thawed eggs progressing to embryos. Between 2005 to 2010, our pregnancy rate has been 53%, showing minimal difference from the standard embryo freezing rates.
Techniques such as vitrification, utilize such high and dangerous levels of cryoprotectant solutions, that the egg cannot withstand exposure for more than 60 seconds. The Embryologist processing the eggs has absolutely no margin for error.
Some crystal formation is inevitable and may occur in the freezing/thawing phases of both programmed freezing and vitrification techniques. To assume otherwise is less than accurate. It is just a matter of degree that determines if the extent of crystallization is lethal or not.
Patient selection is another matter. In vitro fertilization has taught us that nothing replaces young, robust eggs in our quest to achieve high pregnancy rates. It is absurd for patients and fertility clinics to expect high success when the eggs are sub optimal due to age-related deterioration of the internal organelles and the pre-determined cell death known as apoptosis. The annual data published by the Center for Disease Control reveals that the best pregnancy rates are achieved in the 35 years or younger age group. It stands to reason that this subgroup of patients have the best chance for success whether their fresh or frozen eggs are used to achieve pregnancy.
Unfortunately for the consumer, the vast majority of clinics offering “egg freezing” have never even attempted to thaw a single one of their patients’ eggs. This is a glaring example of why egg freezing is still considered “experimental.” In the hands of experienced practitioners who practice the art of egg freezing, the success rate in the favorable patient age group approximates those of a fresh IVF cycle.
Since it is accepted that the definition of fertility treatments is the birth of a healthy baby, I would be curious to know the live birth rates after egg thawing from the fertility clinics and the experts whom you quoted. In our practice, we have 60 sets of parents of frozen egg babies who would disagree with the content of your article.
Like many other areas of medicine, egg freezing and thawing should be left to experienced experts who practice it often and practice it well.
Very sincerely,
David Diaz, MD, FACOG
West Coast Fertility Centers
Frozen Egg Bank, Inc.
Orange County, CA
714-513-1399
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You can read Judy Foreman’s article for the Los Angeles Times newspaper below OR click on the link.
http://articles.latimes.com/2010/aug/16/health/la-he-health-sense-eggs-20100816
Health Sense: Success rate elusive on frozen eggs
The chances of bringing home a baby after harvesting and preserving a woman’s eggs remain unknown. Often eggs are never retrieved.
August 16, 2010 | By Judy Foreman, Special to the Los Angeles Times
Freezing eggs for non-medical reasons — in which a healthy woman harvests and preserves her eggs for later conception — is new enough that there are few reliable statistics on the success of the procedure. “Success” in such cases means a take-home baby, not just an egg that is frozen without damage, or thawed safely or even fertilized to yield a genetically normal, healthy embryo.
“So few women who have frozen eggs have come back to use them [that it's impossible] to quote a clear pregnancy rate on it,” says Dr. Elizabeth Ginsburg, medical director of assisted reproductive technologies at Brigham and Women’s Hospital. Because women usually plan to freeze eggs for many months or years before retrieving them for conception, there simply hasn’t been time to collect enough data.
But the idea is clearly catching on. Nationwide, roughly half of 282 U.S. fertility centers surveyed offer egg freezing, according to a USC study published in the June issue of Fertility and Sterility, a journal of the American Society for Reproductive Medicine. About 400 fertility centers are currently operating in the U.S.
A woman who decides on egg freezing is first given hormones to stimulate egg production. At Boston IVF, the eggs are then retrieved while the woman is under general anesthesia; other centers may use IV sedation plus painkilling drugs.
The process, not usually covered by insurance, can cost $10,000 or more per procedure. Beyond the initial expense, there are annual fees, often hundreds of dollars, to maintain the eggs.
At Boston IVF, a leading fertility center in the U.S. and one of the oldest as well, typical fees are $6,000 for the harvesting and freezing of eggs; that doesn’t even cover the cost of hormones and medications, subsequent fertilization or transfer of eggs to the uterus.
The center has begun offering seminars on the process to young women, many of who are just out of college or graduate school and heading into the work force.
No guarantees
Traditionally, egg freezing “has been used in women with cancer who face imminent loss of ovarian function. But recently, the technology has advanced to the point where it is worth using for women who want to preserve their oocytes for social reasons,” says Dr. Briana Rudick, a reproductive endocrinologist at USC and the lead author of the survey.
Two-thirds of the clinics in the USC survey reported that they made the service available to women for such elective reasons.
There are no reliable numbers for how many women have chosen to have their eggs frozen. About 60 women have done so at Boston IVF, most of them as a hedge against advancing age, says Dr. Kim Thornton, clinical director of the center’s egg-freezing program. So far none has returned for the next step, she said.
Worldwide, more than 900 babies have been born from frozen eggs, according to a 2009 study conducted by researchers at the New York University Fertility Center and published last year in Reproductive BioMedicine Online.
Of course, there are no guarantees that freezing eggs will preserve fertility, just as there are no guarantees — at any age — that a woman can get pregnant naturally. In both cases, the odds get worse as egg quality declines with age.
“Humans are the poorest of all mammalian species in terms of chromosomal integrity,” says Dr. Geoffrey Sher, founder of the Sher Institutes for Reproductive Medicine in Las Vegas, N.M. “With humans, even when they’re young, there’s only a 2 in 5 chance that an egg is normal. By the time a woman is 45, approximately 1 in 15 is normal.”
“Pregnancy rates at age 40 are pretty low even with fresh eggs,” says Ginsburg at Brigham and Women’s. “You can chop that by two-thirds if it’s frozen eggs.”
A young field
The first pregnancy that resulted from a frozen egg occurred in 1986, and two major professional groups, the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine, still consider egg freezing experimental. In fact, they caution that a request to freeze eggs should be reviewed by an institutional review board before being granted.
Still, several advances are nudging the use of egg-freezing forward. One is “vitrification,” in which eggs are frozen within 15 minutes. Typically, eggs have been frozen slowly, over several hours, using programmable freezers that drop temperatures step by step. While many fertility clinics still use this method, it allows for the creation of ice crystals, making egg survival only about 60%, says Michael Tucker, scientific director at Georgia Reproductive Specialists in Atlanta. The claim with vitrification is that the egg survival rate may rise to 80% or even higher.
Testing the genetic viability of both eggs and embryos has also boosted interest in freezing. Several methods are available, including comparative genomic hybridization (CGH), which checks eggs or embryos to be sure they have the correct number of chromosomes. Some embryos appear normal under the microscope but have the wrong number of chromosomes, meaning they are not viable, Sher says.
Bottom line, a woman who wants to conceive a child at some point in the future should carefully consider the option — the risks, costs and unknowns.
Regarding the use of egg freezing, a more recently available choice, Ginsburg advises, “If you want to have a child and it’s feasible socially, do it. … I get infertile patients, married for five years, who couldn’t imagine having a baby in [their] small apartment. That’s a bad reason to wait until age 35. It’s really sad, and I see it a lot.”
