Infertility
What is infertility?
Infertility is defined by the American Society for Reproductive Medicine
(ASRM) as a disease of the reproductive system that impairs the body's
ability perform the basic function of reproduction. Although conceiving
a child may seem to be simple and natural, the physiological process is
quite complicated and depends on the proper function of many factors,
including the following, as listed by the ASRM:
- production of healthy sperm by the man
- production of healthy eggs by the woman
- unblocked fallopian tubes that allow the sperm to reach the egg
- the sperm's ability to fertilize the egg
- the ability of the fertilized egg to become implanted in the uterus
- adequate embryo quality
Who is affected by infertility?
The average chance to conceive for a normally fertile couple having regular,
unprotected intercourse is approximately 25 percent during each menstrual
cycle. In most couples, conception occurs within about 12 months. However,
infertility affects about 10 percent of couples of childbearing age. Infertility
is not just a woman's concern. A problem with the male is the sole cause,
or a contributing cause, of infertility in about 40 percent of infertile
couples. About one-fourth of infertile couples have more than one cause
or factor related to their inability to conceive. About 10 to 15 percent
of couples have no identifiable cause for their infertility after medical
investigation.
What causes infertility?
Many different factors and problems can cause infertility, including
problems in the female reproductive system, the male reproductive system,
or a combination of the two. The following are some of the conditions
or factors that are associated with infertility:
- female factors
- ovulation dysfunction
With this condition, the woman's reproductive system does not produce
the proper amounts of hormones necessary to develop, mature, and
release a healthy egg.
- anatomical problems
Abnormal development or function of the female anatomy can prevent
the egg and the sperm from meeting. The most common anatomical problem
is blockage of the fallopian tubes. Other anatomical problems may
include the presence of pelvic scar tissue from previous surgeries
or infections.
- endometriosis
Endometriosis is a condition in which the tissue that lines the
uterus develops outside the uterus, usually on other reproductive
organs inside the pelvis or in the abdominal cavity. Each month,
this misplaced tissue responds to the hormonal changes of the menstrual
cycle by building up and breaking down, resulting in internal bleeding
which can cause scar tissue to form and affect reproductive organ
function.
- birth defects
Abnormal development and function of reproductive organs resulting
from birth defects can affect fertility. One of the most common
reproductive system birth defects occurs following a woman's exposure
to DES (diethylstilbestrol) taken by her mother during pregnancy.
In years past, DES was given to women at risk for pregnancy loss.
Fetal DES exposure often causes abnormal development of the uterus
and cervix.
- infection
Pelvic inflammatory disease (PID) is caused by a type of bacteria
such as gonorrhea and chlamydia. PID can affect the uterus, fallopian
tubes, and/or the ovaries. It can lead to pelvic adhesions and scar
tissue that develops between internal organs, causing ongoing pelvic
pain and the possibility of an ectopic pregnancy (the fertilized
egg becomes implanted outside the uterus).
- immunological problems
A problem with a woman's immune system can lead to pregnancy loss.
Antibodies (immune or protective proteins) in a woman's system can
fail to recognize a pregnancy, or there may be an abnormal immune
response to the pregnancy. Women can also develop antisperm antibodies
which attack and destroy sperm.
- male factors
- low or absent sperm production
Without proper numbers of healthy sperm, the chance of fertilization
is decreased.
- abnormal sperm function
Sperm must have proper motility and the ability to penetrate the
egg.
- varicocele
This is a condition in which varicose veins develop around the
testes. It is a very common cause of male factor infertility and
is usually treatable and reversible with surgery.
- lifestyle
Use of recreational drugs (i.e., marijuana, cocaine), heavy
alcohol use, cigarette smoking, certain medications, and excessive
heat to the genital area (as in hot tubs) can affect sperm quality
and function.
- hormonal disorders
Improper male hormone or endocrine function can affect sperm production
and fertilization ability.
- chromosomal defects
Certain chromosomal abnormalities are associated with male infertility.
- birth defects
Abnormalities in a man's reproductive system can occur during fetal
development. Some birth defects are due to a man's exposure to DES
(diethylstilbestrol) taken by his mother during pregnancy.
- immunological problems
A man may have antisperm antibodies (immune or protective proteins)
which attack and destroy sperm
How is infertility diagnosed?
When conception does not occur after one year of unprotected intercourse,
after six months in women over age 35, or if there are known problems
causing infertility, a medical evaluation of both the male and female
is recommended. Some obstetrician/gynecologists (OB/GYNs) are able to
provide basic infertility evaluation and treatment. However, many causes
of infertility are best treated by a board-certified reproductive endocrinologist.
This is an OB/GYN who has had additional education and training in infertility
and is certified with the American Board of Obstetrics and Gynecology
in the sub-specialty of Reproductive Endocrinology and Infertility.
Generally, the OB/GYN or reproductive endocrinologist will evaluate specific
situations and perform tests in both the male and female partners to determine
the cause of infertility. The physician is looking for answers to the
following questions:
- Is the female ovulating regularly?
- Is the male producing healthy, viable sperm?
- Are the female's egg and the male's sperm able to unite and grow normally?
- Are there any obstacles to proper implantation and maintenance of
the pregnancy?
The following tests are often part of the basic medical workup for infertility.
Treatment for infertility:
Specific treatment for infertility will be determined by your physician
based on:
- your age, overall health, and medical history
- extent of the disorder
- cause of the disorder
- your tolerance for specific medications, procedures, or therapies
- expectations for the course of the disorder
- your opinion or preference
Once a diagnosis is made, the specialist can work with you to determine
the course of treatment. According to the ASRM, most infertility cases
(85 to 90 percent) are treated with conventional therapies, such as drug
treatment or surgical repair of reproductive abnormalities. Depending
on the cause of infertility, there are many options to offer an infertile
couple.
Types of treatments may include the following:
- ovulation medications
These medications help regulate the timing of ovulation and stimulate
the development and release of mature eggs. They can also help correct
hormonal problems that can affect the lining of the uterus as it prepares
to receive a fertilized egg. Ovulation medications can stimulate more
than one egg to be released which increases the possibility of having
twins and other multiples. Some of the common ovulation medications
include the following:
- clomiphene citrate
- human menopausal gonadotropins - medications containing follicle-stimulating
hormone (FSH) and luteinizing hormone (LH)
- follicle-stimulating hormone (FSH)
- intrauterine insemination
For some conditions, including low sperm count and cervical mucus problems,
a procedure that places specially washed and prepared sperm directly
into the uterus through a small catheter (flexible tube) helps increase
the chances for conception. This procedure is often used in combination
with ovulation medications.
- surgery
Surgery may be used to treat or repair a condition that is causing infertility
such as fallopian tube blockage, or endometriosis. A common surgical
procedure often used as part of the diagnostic workup of infertility
is the laparoscopy. In a laparoscopy, a small telescope inserted into
the abdominal or pelvic cavity allows internal organs to be visualized.
Some procedures to treat infertility can be performed using instruments
inserted through the laparoscope.
- assisted reproductive technology (ART)
For some couples, more extensive treatment is needed. With most forms
of ART, the sperm and egg are united in the laboratory and the fertilized
egg is returned to the woman's uterus where it can implant and develop.
Although ART procedures are often costly, many are being used with success.
These include the following:
- in
vitro fertilization (IVF) - involves extracting a woman's
eggs, fertilizing the eggs in the laboratory with sperm, and then
transferring the resulting embryo(s) into the woman's uterus through
the cervix (embryo transfer) where it can develop. Most couples
transfer two embryos, however, more may be transferred in certain
cases. IVF is the most common form of ART and it is often the treatment
of choice for a woman with blocked, severely damaged, or absent
fallopian tubes. IVF is also used for infertility caused by endometriosis
or male factor infertility. IVF is sometimes used to treat couples
with long-term unexplained infertility who have not been able to
conceive with other infertility treatments. According to the ASRM,
the average cost of one IVF cycle in the United States is $7,800.
More than one IVF cycle, however, is usually needed.
- intracytoplasmic sperm injection (ICSI) - a procedure in
which a single sperm is injected directly into an egg; this procedure
is most commonly used to help with male factor infertility problems.
- gamete intrafallopian transfer (GIFT) - involves using
a fiber-optic instrument called a laparoscope to guide the transfer
of unfertilized eggs and sperm into the woman's fallopian tubes
through small incisions in her abdomen. GIFT is only used in women
with healthy fallopian tubes.
- zygote intrafallopian transfer (ZIFT) - involves fertilizing
a woman's eggs in the laboratory and then using a laparoscope to
guide the transfer of the fertilized eggs (zygotes) into her fallopian
tubes. ZIFT is only used in women with healthy fallopian tubes.
- donor eggs - involves an embryo formed from the egg of
one woman (the donor) being transferred to another woman who is
unable to conceive with her own eggs (the recipient). The donor
relinquishes all parental rights to any resulting offspring. ART
using donor eggs is much more common among older women than among
younger women. The likelihood of a fertilized egg implanting is
related to the age of the woman who produced the egg. Egg donors
are typically in their 20s or early 30s.
- embryo cryopreservation - a procedure in which embryos
are preserved through freezing (cryopreservation) for transfer at
a later date. This procedure is often used when an IVF cycle produces
more embryos than can be transferred at one time. The remaining
embryos can be transferred in a future cycle if the woman does not
become pregnant.
What is unexplained infertility?
About 10 to 15 percent of couples have unexplained infertility, for which
a cause, despite all investigations, is not found. Unexplained infertility
does not mean there is no reason for the problem, but that the reason
is unable to be identified at the present time.
If you suspect you are experiencing infertility, seek medical consultation
early. The age of the woman and the duration of the couple's infertility
may influence the success of treatment.
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