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Human
beings are remarkably fertile. Most females are capable
of conceiving and bearing children beginning
in their mid-teen years. While women in industrialized
societies usually bear children in their 20s and 30s,
women can give birth well into their 40s and beyond.
Men can be fertile into extreme old age. Unlike most
mammals, humans can mate successfully year round;
fertility is not restricted to a particular season
of the year or to brief episodes of female heat.
However,
the process of reproduction is immensely complex.
For conception to take place and pregnancy to begin,
hundreds of individual hormonal, chemical, and physical
events must take place in a precise order. A single
disruption, small or large, in any of these events
and conditions can cause infertility. In the late
20th century, medical science has made great advances
in understanding each stage of the reproductive process
and in identifying the problems that can occur at
each step. In an increasing number of cases these
barriers can be corrected or worked around in order
to achieve fertility for about 65% of couples who
seek the help of fertility specialists. Although most
of the biological work of creating children must still
be done by the human body science can provide substitutes
for a few key processes.
Is infertility becoming
more common? Despite public worry and discussion,
the actual incidence of infertility has remained fairly
stable over the years. One American couple out of
5 or 6 currently experiences infertility. Infertility
grows more common with increasing age; about 33% of
couples in their late 30s are infertile. The age factor
has taken on new importance as many people in the
United States and similar industrialized countries
have put off marriage and children until certain educational
or career goals are reached. Another social factor,
the increasing difficulty of adoption (a result of
improved birth control and the availability of legal
abortion) has increased the demand for medical answers
to infertility, regardless of their complexity and
high cost.
Even
the most fertile human couple does not necessarily
conceive the first time sexual intercourse takes place.
In fact, the chance of conception in any given month
among fertile couples attempting to conceive is about
20%. To avoid unnecessary testing and treatment, most
doctors will not make the diagnosis of infertility
until one year of unprotected intercourse has failed
to result in pregnancy. Some cases, involving older
couples or existing evidence from previous treatments,
may be diagnosed sooner and treated more aggressively.
Once the diagnosis is made, examinations, testing
and history-taking begin to find the cause(s) of infertility.
In about 30% of infertility cases, the problem can
be found solely in a medical problem of the woman's;
in another 30%, male factors alone cause the infertility;
and in another 30% of cases, both partners have conditions
which render the couple infertile. In the remaining
10% of cases, no clear cause can be found.
Women
undergo a physical and pelvic examination, laboratory
tests, one or more imaging procedures and, in some
cases, exploratory surgery to locate the problem which
may be causing infertility. Men are tested for the
presence, quantity and quality of their sperm. Common
causes of male infertility include insufficient hormone
levels (which may be supplemented), a varicocele (tangle
of veins surrounding the testicle that can be corrected
surgically), blocked tubes which carry sperm (which
can sometimes be surgically repaired or bypassed),
untreated diabetes or prostate disease and other conditions.
After
testing is complete, doctors devise a strategy for
each couple to increase fertility. The optimum treatment
is one that allows existing natural processes to take
place. Sometimes, very small adjustments in sexual
frequency and timing may result in pregnancy. Patients
are taught to identify the woman's most fertile times
so that intercourse can take place. Practices that
temporarily result in lowered sperm counts or abnormally
formed sperm, including the use of certain medications,
alcohol, marijuana, and hot tubs or saunas, can be
curtailed.
Once thought radical and futuristic but now considered
quite routine, the best-known medical "fix"
for infertility is in vitro fertilization. "In
vitro" means "in glass," and it involves
the mixing of sperm and egg in the laboratory, outside
the human body. After fertilization takes place, the
zygote (fertilized egg) may be surgically placed in
the woman's fallopian tube. Alternatively, it may
be allowed to develop further outside the body and
then be introduced into the uterus in an effort to
establish a pregnancy.
One
of the most recent developments in ART (assisted reproductive
technology) is intracytoplasmic sperm injection (ICSI).
This microsurgical procedure involves injecting a
single sperm into an egg, allowing men with extremely
low sperm counts to become fathers. Further advances
in ART are expected from the quickly evolving fields
of genetics, imaging, and biotechnology.
The
rapid development of new medical technology has raised
many ethical and legal issues. Society is only beginning
to devise acceptable answers. Philosophers and theologians
ask whether humans have the right to tamper with natural
processes. Physicians and their patients have more
immediate concerns-what shall be done with "extra"
eggs, sperm, and zygotes? While it is possible to
selectively abort one or more embryos to improve the
chances of the others survival and to reduce the burden
on parents of raising quintuplets or sextuplets, is
this a justifiable act? Is infertility treatment a
basic right that should be paid for by medical insurance,
or an elective luxury, similar to cosmetic surgery,
available only to those who can afford it?
Due
to all the ethical issues raised by infertility treatment,
and because the treatment itself may involve considerable
time, expense, and loss of privacy, many couples find
the procedure extremely stressful. Physicians experienced
in the field recommend both private counseling and
infertility support groups to assist couples in their
journey through the process.
- Infertility-Discussion
- Infertility 101- An Overview, Karen Kaplan, MD Georgia Reproductive Specialists
- Overview by Mark Trolice, MD
- Male Factor Infertility
- Cervical Factor Infertility
- Endometriosis
- PCOS
- Ovulatory Dysfunction
- Tubal Factor Infertility
- Uterine Factor Infertility
- Unexplained Infertility
- Infertility Overview- Samuel Thatcher, MD
- PRESERVING
REPRODUCTIVE OPTIONS IN ONCOLOGY PATIENTS ,
by Bradford Kolb, M.D., F.A.C.O.G.,
Board Certified, Reproductive Endocrinology and Infertility
- THE
CONTEMPORARY FERTILITY EVALUATION, by Daniel Potter, M.D., F.A.C.O.G.,
Board Certified, Reproductive Endocrinology and Infertility,
Huntington Reproductive Center
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