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has been a little more than 25 years since the first baby was born in
England following in vitro fertilization. In that quarter of a century,
there have been dramatic advances in Assisted Reproductive Treatments
(ART), with over one million healthy babies being born worldwide from
these procedures. The applications and indications for these procedures,
as well as the advances in different techniques, equipment and medications
have been significant.
Throughout the past 25 years, this field has had to grapple with ethical
and legal issues, which sometimes have not kept pace with scientific
advances. Issues such as cloning, stem cell research, posthumous reproduction
and genetic engineering, are a few of the areas where legislative intervention
has been, and still is, necessary.
One of the big issues in our field remains the incidence of multiple
pregnancies, and the problems associated with these outcomes. In particular,
pre-term labor and prematurity are important issues, which may have
devastating consequences. The good news is that new advances in the
measurement of molecular markers of embryo competency can enable physicians
to identify those embryos most likely to yield a pregnancy and in so
doing, feel comfortable transferring fewer embryos. This, in turn, will
decrease the incidence of multiple pregnancies, which are directly related
to the number of embryos transferred back to the uterus.
In this day and age, with all of the options available to patients,
there should be no couple who cannot have a family, be it with their
own biological child, adoption or third party reproduction. Regrettably,
these treatments are still not covered by many insurance companies,
due in large part to the fact that they do not consider infertility
a disease. They also have legitimate concerns about the incidence of
high order multiple pregnancies and the consequences thereof, especially
the incidence of prematurity and risks of cerebral palsy associated
with this problem. This situation sometimes places significant burdens
on those who need to avail themselves of these treatments.
Some of the newer advances in the field include the following:
Pre-Implantation Genetic Diagnosis (PGD):
In this procedure, a cell (blastomere) is removed from an 8 cell (3-day-old
embryo) and analyzed for its chromosomal make-up. Presently only nine
of the possible 23 chromosomes are able to be analyzed. This research
is advancing quickly, and with the knowledge available from the Human
Genome Project, it is likely that within the relatively foreseeable
future, it will be possible to test all 23 chromosomes. The greatest
application of PGD lies in the detection of single gene defects (e.g.
cystic fibrosis, sickle cell disease, etc.), where carriers of these
conditions can be evaluated, probes developed and the removed blastomere
tested to determine whether the defective genes are present or not.
If affected, those embryos are not transferred. Besides the fact that
not all chromosomes can be tested, the techniques are difficult and
if performed by those not proficient in them, this can cause irreparable
damage to the embryos.
Embryo Marker Expression Test (EMET):
In contrast with PGD, this test is performed in a completely non-invasive
manner by removing a small amount of the fluid surrounding 2- and 3-day-old
embryos, and testing this fluid for molecular markers. One such marker
is soluble HLA-G. This marker has been shown to be strongly correlated
with the implantation potential of the embryo. It is imperative that
embryos are cultured singly in dishes in the lab. When they test positive
for these markers, fewer, high quality embryos can be selected for transfer,
thereby maintaining acceptable pregnancy rates, yet significantly reducing
the incidence of high order multiple pregnancies. It is likely that
in the near future, additional molecular markers of embryo competency
and embryo health will be identified, which will open all kinds of possibilities
for research and therapeutics in this field.
Immunology:
A recognition and understanding that immune tolerance is pivotal for
successful reproduction has been an important development in recent
years. Higher levels of so-called Natural Killer Cells and various cytokines
can destroy early embryos after implantation. Immune modulation therapy
using IVIG has been demonstrated to reduce the levels of these cells
thereby making growth of early implanted embryos more likely to occur.
When coupled with steroid therapy and anti-coagulation treatment, couples
who suffered from repetitive miscarriages and repeat IVF failures are
now able to successfully reproduce.
Third Party Reproduction:
Egg donation and Gestational Surrogacy are now frequently performed.
These options have evolved considerably over the past decade and enjoy
very high success rates (50-75 percent range). Unfortunately, the laws
vary considerably in different parts of the country and world. There
are significant psychological issues when performing these treatments
and counseling is often an integral part of the process. Furthermore
they are quite costly, however these options have opened up enormous
possibilities for successful reproduction in couples who can benefit
from them.
Oocyte (Egg) Freezing:
It is well known that reproduction declines significantly as a function
of age, declining
after age 30 and dramatically after age 40. When perfected, egg freezing
will likely result in a
paradigm shift in how young women prioritize their lives. It may reach
the point where, upon entry into college, a young woman will have eggs
frozen to “place the biological clock” on hold, so to speak.
She will then pursue career objectives and return several years later
with her partner to reproduce from the eggs which would have been frozen
years before. One of the important obstacles of this procedure has been
damage to the chromosome spindle upon freeze/thaw of the oocyte. It
is important at this time that young women are not given false expectations
about the likelihood of successful reproduction taking place from frozen
oocytes. It is likely that these techniques will be perfected in the
near future, but they are not yet at that place. There have been over
100 healthy babies born as a result of egg freezing to date and the
research in this area is very active.
Sex Selection:
New advances in methods to separate sperm into X-bearing (girls) and
Y-bearing (boys) fractions have shown some promise. The techniques are
not yet perfected and possibly will never reach 100 percent perfection.
With these possibilities of family balancing come some ethical dilemmas,
which must be kept in mind. These involve appropriation of funding resources,
societal sex ratio imbalances and moral considerations. These techniques
do hold promise for those affected with sex-linked disorders where it
is possible to obtain embryos of a particular sex.
Secondary Infertility:
Secondary infertility affecting those who have previously reproduced
successfully is often very frustrating. It is frequently related to
age and a decline in egg quality as a function of age. The good news
is that the vast majority of those affected will be able to successfully
reproduce if they are willing to accept treatments such as egg donation.
Infertility affects approximately 15 percent of all
couples trying to conceive. Unfortunately only a small percentage of
those who need treatment, actually receive treatment. Ignorance of available
treatment options, embarrassment and lack of affordability are the most
frequently cited reasons for this disparity. In this day and age, there
should be no couple who remains childless if they are willing to overcome
personal obstacles which may be in their way.
Joel H. Batzofin, M.D., FACOG, medical director
of the Sher Institute for Reproductive Medicine in New York, is one
of the world’s leading experts in the field of in vitro fertilization
(IVF) and Assisted Reproduction Technologies (ART). A pioneer in the
field of “third party parenting” and men’s fertility,
he has authored many scientific articles and lectured throughout the
world on various aspects of ART. Geoffrey Sher, M.D., FACOG, founder
and executive medical director of the Sher Institute for Reproductive
Medicine, is a world-renowned expert, author, consumer advocate and
researcher in the fields of IVF and ART. In his 22 year career, he has
been influential in the births of over 15,000 in vitro fertilization
(IVF) babies.
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