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Fertility Preservation for Women with Cancer
Cancer in young women, of reproductive age is fortunately overall a rare
event, yet, still occurs more frequently than often believed. Despite improving
cure rates, and maybe exactly because of them, the experience can be devastating.
The reason is that the same treatments which potentially cure the malignancy,
frequently, at the same time, obliterate ovarian function. Young women, therefore,
fortunately survive at ever increasing rates but, concomitantly, are rendered
sterile, unless they are willing to conceive with (third party) donated eggs.
Complete loss of ovarian function is usually due to either chemo-, radiotherapy
or both. In recent years, modern medical care has started to make some early
inroads when attempting to maintain at least some ovarian function after cancer
treatment. Various ideas and technologies have been attempted. None has, so
far, proven universally successful, though steady progress is being made.
While it remains important to understand that all currently
available treatments should, as of this point, still be considered experimental,
their use in a clinical situation, where the alternative is functional sterility,
makes sense as long as patients understand the experimental nature of these
treatments and accept the fact that none of them can guarantee fertility
in the future. CHR offers all of the below described methods of fertility
preservation but requires that patients acknowledge their experimental nature
by signing an appropriate “experimental” informed consent.
What unifies all of the currently available treatments
is the need for quick and proactive treatment once the initial cancer diagnosis
has been made.Since most cancer specialists urge rapid therapeutic responses,
the time to act is usually very limited. Affected patients are, therefore,
well advised to consult fertility experts who can react quickly. In addition,
close cooperation and coordination between fertility and cancer experts is
of absolutely crucial importance.
GONADOTROPIN RELEASING AGONIST TREATMENT
Mostly based on the work of an
Israeli group, we know that the devastating effects of, at least some, chemotherapeutic
agents can be partially mitigated by pre-treating affected women with a hormone,
called gonadotropin releasing agonist (GnRH-a). This medication puts the
ovaries into a “rest” stage
and, in doing so, can diminish the toxic effects of the chemotherapy on the
eggs within the ovary. This medication works, however, only in conjunction
with certain chemotherapies.
EGG (OOCYTE) FREEZING
A considerable, by many in the profession believed
to be an excessive, amount of publicity has recently surrounded the concept
of egg freezing. Indeed, some fertility centers, and specially created commercial
enterprises, have, in our opinion, greatly oversold the concept. CHR has been
offering egg freezing as a clinical service for over one and a half years.
Yet, we have been offering the service only as an experimental procedure,
with appropriate informed consent.
Egg freezing, as much as our techniques have improved,
still lags behind embryo freezing. Paradoxically, a “simple” egg freezes (and thaws) much
less reliably than the more “complex” embryo. Consequently, we
can not predict the outcome from egg freezing with similar accuracy to embryo
freezing. In other words, when we have a certain number of embryos cryo-preserved,
we have a pretty decent idea what their pregnancy chance will be, once thawed
and transferred into a uterus. This, in turn, allows us a rather accurate calculation
as to how many embryos a patients needs to freeze if she wished to establish
a certain likelihood of pregnancy from these cryo-preserved embryos. Our predictive
abilities in regards to egg freezing are not as good yet and, therefore, our
ability to advise patients is much more limited.
The freezing of egg (oocytes) requires a full IVF cycle. This usually means,
even when shortened cycle stimulation is used, a delay of at least one month
in cancer therapy. It is also important to remember that one cycle of IVF will
result in only a limited numbers of eggs which, given what we discussed above,
may offer only a very limited pregnancy chance in the future.
OVARIAN FREEZING
This represents probably the most experimental treatment
discussed here as, so far, only two pregnancies have been reported world-wide,
utilizing the concept of re-implanting ovarian tissue. Here is how it is supposed
to work: A young woman, who wishes to preserve her ovarian function prior to
cancer treatment, undergoes surgery in which (at least) one of her ovaries
is removed. The removed ovary is dissected and the portion where the follicles
are housed is cut into thin slices which are frozen. Months to years later,
when the patient is considered cured from her cancer, and if her ovarian function
has, indeed, not returned in the ovary (usually) left behind, one or more of
the frozen ovarian “slices” are
re-implanted into her body. Different locations and techniques have been reported
for this re-implantation procedure and it currently appears that the best techniques
involve re-implantation into the ovarian capsule left behind during the first
surgery. Indeed, both reported successes, involving, re-implantation of ovarian
tissue, have followed such surgical techniques.
The world wide experience with ovarian freezing is obviously
still very small. The concept, however, appears promising and CHR is, therefore,
offering ovarian freezing on an experimental basis. The emphasis here is,
however, still, as well, on “experimental” because success rates remain to
be defined and, at least one paper from Israel, reported metastatic cancer
cells in a removed ovary, thus creating, at least theoretically, the risk that
the re-implantation of ovarian fragments could re-introduce cancer into a previously
cured patient.
We, therefore, cannot overemphasize the importance of explaining to patients
the experimental nature of all of these treatments. The American Society for
Reproductive Medicine concurs with this assessment and, only recently, in a
published opinion reemphasized this point.
When patients are diagnosed with cancer, they are at their most vulnerable.
We consider it an absolute ethical obligation to advise them, under such circumstance,
with passion but, at the same time, openly and without hype. The clinical options
for preserving fertility are increasingly promising, but still far from perfect.
As long as this is understood, expectations, down the road, will be met. If
expectations are, however, allowed, or encouraged, to become unrealistic, patients
will feel victimized for a second time when those expectations, months or years
later, cannot be met. We, therefore, always make it a point to stress that,
even under the worst of all circumstances, when none of the here described
methods of fertility preservation turns out to be successful, we always have
the wonderful option of egg donation left. In such cases, by the time most
patients give birth, they usually have forgotten where the egg came from that
produced their baby!
If you want more information regarding this
programs, Contact
Us. Please include your specific issue and question or concern.
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