INFERTILITY: The Treatments, The Questions
Assisted reproductive technology has given hope to many
infertile couples who want to have a child. Does it matter which method or
procedure is chosen?
A BABY BOOM THROUGH ASSISTED REPRODUCTION
On July 25, 1978, a unique birth took place in Oldham,
England, when a baby girl named Louise Joy Brown entered the world. Louise was
history’s first test-tube baby. Nine months earlier, Louise had been conceived
in a laboratory through a process called IN VITRO FERILIZATION [IVF].
By means of this procedure, an egg extracted from her mother
was united with a sperm in a glass dish. Two and a half days later, after the
egg cell had subdivided into eight microscopic cells, this little cluster of
dividing cells was inserted into her mother’s uterus to develop normally.
Louise’s birth opened up a whole new chapter in the treatment of infertility.
IVF gave momentum to what is now
known as ASSISTED REPRODUCTIVE TECHNOLOGY [ART], which includes all kinds of
fertility treatments in which both egg and sperm are handled. Consider some
examples. In 1984 a woman in California, U.S.A., gave birth to a baby developed
from an egg donated by another woman.
The same year, in Australia, a
baby was born from an embryo that had been frozen. In 1994 a 62-year-old woman
in Italy gave birth, using donated eggs and her husband’s sperm.
A PROGRESSIVE DEVELOPMENT
Now, some 25 years after Louise
Joy Brown was born, researchers have assembled a battery of medicines and
high-tech procedures that have utterly transformed fertility treatment. Such
breakthroughs have led to a dramatic increase in the number of children born by
means of assisted reproduction.
In 1999, for example, ART
resulted in the birth of over 30,000 babies in the United States alone. In some
Scandinavian countries, between 2 and 3 percent of the children born each year
have been conceived by such means. Worldwide, about 100,000 children are born
annually as a result of IVF treatment. It has been estimated that about one
million such children have been born since 1978.
ART is used mainly in developed
countries. Each treatment, or cycle, cost thousands of dollars, and national
health services, employer-sponsored plans, and private insurances do not
usually cover the costs. Time magazine noted that “a 45-year-old woman who has
gone through seven cycles of IVF can easily spend $100,000 on treatment.”
Nevertheless, assisted
reproductive gives hope to many infertile couples whose only alternative when
it comes to having children has been adoption. Now the various infertility
techniques address many of the female and male causes of infertility. Among the
causes of female infertility are an OVULATION DISORDER, BLOCKED FALLOPIAN
TUBES, OR ENDOMETRIOSIS. Male infertility is often associated with LITTLE OR NO
SPERM production.
WHY SO POPULAR?
One reason for the popularity of assisted reproduction is
the modern life-style. A report published by the American Society for
Reproductive Medicine states: “The average age of childbearing has increased
over the past three decades as more women have pursued higher education and
careers and postponed marriage. Concurrently, a large cohort of women born
during the ‘Baby Boom’ [1946-1964] have reached their late reproductive years,
resulting in more women in this age group seeking assistance for fertility.”
Some women may not realize how quickly their fertility
declines as they get older. According to the U.S. Centers for Disease Control
and Prevention, by the time a woman is 42 years old, her chances of having a
baby using her own eggs are less than 10 percent. Donor eggs are thus often
used for older women seeking ART treatment.
In a new twist, some infertile couples resort to embryo
“adoption,” obtaining an embryo left over from the infertility treatment of
another couple. It is estimated that in the United States alone, about 200,000
frozen embryos are being stored. A CBS news report recently revealed: “Embryo
donation has been quietly taking place on a small scale for years.
Not surprisingly, the developments in the field of assisted
reproduction raise a number of questions. How may this kind of childbearing be
viewed from an ethical and moral standpoint?
SOME TYPES OF FERTILITY TREATMENTS
1.
AI [ARTIFICIAL INSEMINATION]. A procedure in
which semen is introduced into the female reproductive organs by other than
natural means. AI is an option often tried before the procedures described
below.
2.
GIFT [GAMETE INTRAFALLOPIAN TRANSFER]. A
procedure that involves removing eggs from a woman’s ovary, combining them with
sperm, and using a LAPAROSCOPE [an instrument used for examining the abdominal
cavity to place the unfertilized eggs and sperm into the woman’s fallopian tube
through small incisions in her abdomen.
3.
ICSI [INTRACYTOPLASMIC SPERM INJECTION]. A
procedure in which a single sperm is injected directly into an egg.
4.
IVF [IN VITRO FERTILIZATION]. A procedure that
involves removing eggs from a woman’s ovaries and fertilizing them outside her
body. The resulting embryos are then transferred into her uterus through the
cervix.
5.
ZIFT [ZYGOTE INTRAFALLOPIAN TRANSFER]. A
procedure in which eggs are collected from a woman’s ovary and fertilized
outside her body. A resulting fertilized egg is then inserted into her
fallopian tube through a small incision in her abdomen.
WHAT ARE THE RISKS
HUMAN ERROR: In the United States, the Netherlands, and
Great Britain, fertility clinics have by mistake mixed up and embryos. In one
case a couple got twins of another race, and in another case a woman gave birth
to twins who were of two different races.
MULTIPLE BIRTHS: Studies have shown that multiple births –a
result of multiple embryos transferred into a womb –increase the chances of
premature birth, low birth weight, stillbirth, and long-term disability.
BIRTH DEFECTS: According to one study, children conceived
through IN VITRO FERTILIZATION have an increased risk of birth defects, such as
heart or kidney problems, cleft palate, and undescended testicles.
MOTHERS’ HEALTH: Complications from hormonal treatment or a
multiple-fetus pregnancy increase the risks for mothers.
WHAT IS A PREEMBRYO?
The term “preembryo” refers to the unborn’s stage of
development during the first 14 days after fertilization. After that, it is
called an EMBRYO until the end of the eighth week. From then on, it is called a
FETUS. Why is the word “preembryo” used?
According to the International Journal of Sociology and
Social Policy, the term was “used as the rationale for permitting human embryo
research” during the first 14 days after conception. One reference work says:
“If one defines the embryo as the structure destined to become the baby, its
earliest rudiments do not form until about two weeks after the sperm meets the
egg.”
But can this preembryo be dismissed as a mere mass of cells,
fit for little more than research? Consider what really happens during this
two-week period. After the sperm has penetrated the egg. It takes about 24
hours for the male and female chromosomes to fuse.
During the next few days, the cell divides. Within four or
five days after fertilization, the cluster of cells develops into a hollow
sphere [still smaller than a pinhead] with an outer cell layer and an inner
cell mass.
It is now known as a BLASTOCYST. Many of the cells of the
outer layer will develop into non-embryonic tissues. From the inner cell mass,
however, the baby itself will develop.
About a week after fertilization, implantation in the womb
occurs. The blastocyst attaches itself to the womb and begins the construction
of the placenta, which will allow the passage of oxygen and food from the
mother’s bloodstream and the release of wastes.
According to the book
Incredible Voyage –Exploring the Human Body, by about day nine the inner cell
mass starts “the task of constructing a new human being.” It adds: “Those 20 or
so cells must perform a series of restructurings and differentiations over
another five or six days to create the first structural element of the actual
embryo.”
So by the end of the second week, this “first
structural element,” from which the central nervous system eventually develops,
begins to appear.
Because of this preparatory
step-by-step process that goes on within the early human embryo, some argue that
“there is no one biological event or movement that can be considered the start
of a new embryo.”
However, believe that life begins
at conception. The fact that the original fertilized cell contains the program
for the construction of the placenta, the implantation, the connections with
the mother’s blood vessels.
WHAT ABOUT
PREIMPLANTATION GENETIC DIAGNOSIS
A new development in test-tube fertilization is called
PREIMPLANTATION GENETIC DIAGNOSIS. This involves genetically screening embryos
and then selecting the one that is to be implanted into the uterus. Commenting
on the implications of this technique, the book Choosing Assisted Reproduction
–Social, Emotional and Ethical Considerations explains: “Soon [scientists] will
be able to determine physical, intellectual, and perhaps emotional and social
characteristics in an embryo.
Thus in the not too distant future
it will be possible for parents to select some of their offspring’s
characteristics. And although many people would support the use of
preimplantation genetic selection for couples who are carriers of a dreaded
disease, many will not support this technology for couples who wish to have a
child of a particular sex –or in the future, for a child with blue eyes, or
musical talent, or who will be tall.
“Preimplantation genetics, like
many other technologies, raises the question of whether, because something can
be done, it should be done… The dilemma is where to draw the line –if anywhere
–on this slippery high technological slope.”
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