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Infertility
What exactly mean by infertility?
Strictly speaking, an infertile patient is
one who has no chance of getting pregnant without some
medical assistance. In reality, few patients are completely
infertile and most are "subfertile, in the sense that they
have reduced chance of getting pregnant. In general patients
are classified as infertile or subfertile if pregnancy has
not occurred after one year of regular, unprotected sexual
intercource-that is no contaception has been used.
Infertility may be caused by problems in men, in women or in
both. In about 30% of cases the causes are purely male, 30%
the causes are purely female and in ramainder there problems
are on both sides. The man may produce no sperm, too few,
immotile or abnormal sperm. He might be impotent, or suffer
from premature or retrogate ejaculation. The woman may not
ovulate or ovulate infrequently. She may have blocked tubes,
endometriosis, or abnormalities in the uterus such as
fibroids. Many women are getting married at an older age and
once thay are married they are more likely to delay having
children. Sexually transmitted diseases are more common
nowdays and many individuals have more sexual partners than
in the past so thay run a greater risk of transmitting or
acquiring infections. These infections may produce pelvic
inflammatory disease which in turn causes blocked fallopian
tubes. Several recent surveys have indicated that about one
in every six marriages has a fertility problem.
INSEMINATION
Insemination can be either into
cervix or into the uterus itself.
In the first procedure, the patient lies on an examination
table, a speculum is passed into the vagina and the cervix
is visualized. The semen is introduced directly into the
cervix and vagina.
In the second method of artificial
insemination with the husband's semen the patient adopts a
similar position, a fine plastic tube is inserted into the
uterus and sperm are injected directly into the uterine
cavity. This procedure is called intra-uterine
insemination (IUI). The sperm need to be specially
prepared in the laboratory before use. This can be done by
"washing" the semen repeatedly with special
laboratory fluid and then spinning the tube containing the
liquid at high speeds to remove the sperm.
"Swim-up" techniques can also be used. In these the
semen is mixed with laboratory fluid and the healthy sperm
are allowed to swim up to the surface..
IVF - IN-VITRO FERTILIZATION
IVF stands for in-vitro fertilisation,
commonly known as test-tube baby treatment. The basic
principle involves removing one or more mature eggs (the
medical term for eggs is oocytes) from the ovary,
fertilising them outside the body, using sperm from the
partner or from a donor and then transferring one or more of
the fertilised eggs back into the uterus. The procedure
whereby embryos are transferred into the uterus is called
embryo transfer, often referred to as ET. After their
collection, the eggs are placed in a culture medium which
nourishes them. In the meantime, a sample of the partner's
sperm is prepared by a special washing technique to remove
the seminal plasma and separate out the healthy sperm. About
100 000 motile sperm are added to each egg, approximately
4-6hours after egg collection, to allow fertilisation to
take place.The exact length of time the eggs are incubated
before the sperm are added depends on the maturity of the
eggs. Once fertilisation occurs, two pronuclei (one male and
one female) can be seen under the microscope. The fertilised
egg is grown in laboratory until 2 days after egg collection
when it should be ready for transfer into the uterus. At the
time of transfer, embryo is normally at the 2- to 8-cell
stage. There are several ways of measuring the success rate.
The two that have been used commonly are the pregnancy rate
per cycle of treatment commenced and the live birth rate per
cycle of treatment commenced (the "take home baby rate").
The factors that affect these outcomes are age of the
patient, the reason for infertility, the number of embryos
transferred in the particular cycle and the quality of the
IVF treatment programme.
ICSI - MICROMANIPULATION
ICSI is easy to understand.The egg has
a tough outer coating called the zona pellucida, which is
thought to be the main barrier to the penetration of sperm.
In cases of male factor infertility the ability of sperm to
penetrate the zona may be reduced. Several micromanipulation
procedures have been devised to help the sperm pass trough
the zona. At present, these methods are very much at the
research stage but are being tried in cases of severe male
infertility when conventional IVF has failed.
ICSI revolutionized the treatment of
fertilization failure. In traditional IVF, the sperm were
placed next to an egg in a small laboratory dish. With ICSI,
a tiny glass tube (pipette) is made with a sharp point. With
the aid of powerful microscopes and robotic manipulators
capable of microscopic movement, a single sperm is aspirated
into the pipette.
Next, a second glass tube is made with a large opening. By
applying a small amount of suction, the egg can be held in
place. Using the robotic manipulators, the pipette
containing the sperm is brought next to the egg.
Finally, the sharp pipette is pushed into the egg, the sperm
is released, and the pipette is withdrawn. If fertilization
has been successful, then the next day two small dark,
circular structures called pronuclei will be visible. If the
now fertilized egg is functional it will start to
divide--first into 2 cells, then 4 and so-on.
SPERM ANALYSES
Why are sperm tests so important?
As the criteria for assessing sperm depend on a fixed
period of abstinence, the man is ask to abstain from sex or
masturbation for 3 days. He then has to produce a semen
sample by masturbation into a clean glass or plastic
container. The sample of semen should be brought to the
laboratory as soon as in practical, preferably within an
hour of being produced. In cold weather the container should
be kept in an inside pocket on the way to the laboratory.
Our office have apart room for giving samples so that is
possible to give sample there. In the usual semen analysis
is need to check: volume of ejaculate, the acidity -pH, the
sperm density, percentage of motile sperm, the morfology
(shape), and the number of white blood cells in the semen. A
test is also usually done to detect sperm atibodies.
HSG - HISTEROSALPINGOGRAM
AND HORMONE ANALYSES
HSG tells about
state of uterine cavity-histerogeram as well as the inside
of the fallopian tubes-salpingogram. If the tubes are
blocked, the salpingogram will show the site of the blockage
since dye cannot flow past the block. The HSG will also
reveal any swelling of the tube-hydrosalpinx which occurs
because of tubal blockage.The hysterogram is useful to check
the inside of the uterus, particularly in cases of recurrent
miscarriage. An HSG provides information about the inside of
the uterus and fallopian tubes. It allows a direct view of
this organs.
What hormone test are done for infertility?
In women, the hormone tests commonly done for
infertility are measurements of blood levels of follicle
stimulating hormone-FSH, luteinising hormone-LH, oestradiol,
prolactin, testosterone and progesterone. Not all
infertility patients require all these tests. These hormone
concentrations are measured if the patient has irregular,
infrequent or absent menstrual periods to try to determine
the cause. In men hormone tests are not needed so often as
in women. If there is a low sperm count, less than 5mil/ml,
then the level of FSH is high it means that the testes have
failed to respond to the appropriate hormonal stimulation.
This implies that the process of sperm production is so
impaired that no treatment will be of any benefit. On the
other hand, a normal serum FSH concentration in a man with
azoospermia suggests the cause is a blockage that is
perventing the sperm from reaching ejaculate. Such cases
need evaluation by a surgeon specialising in male
infertility to determine whether the blockage can be
relieved surgically.
TESA AND MESA
Male factor requires the production by the
testis of large numbers of normal spermatozoa through a
complex process known as spermatogenesis.
This process comprises successful transformation of the
round spermatid into the complex structure of the
spermatozoon. Regulation of that process occurs at two major
levels: hormonal and endocrine and paracrine-autocrine.
Defects occurred during spermatogenesis can result in the
failure of the entire process and lead to production of
defective spermatozoa and reduction or absence of sperm
production.
Different infections or sexually transmitted diseases may
damage male fertility. Gonorrhea is implicated in the
etiology of obstructive azoospermia.
Most common pathological conditions known, which can be
defined as causes of male infertility are: varicocele, male
accessory gland infections, seminal abnormalities unknown
cause and endocrine causes. Also one of problems are genetic
abnormalities.
Today there are new advanced techniques to overcome such
problems and to obtain enough spermatozoa needed for ICSI or
even for IVF.
There is possible to obtain epididymal spermatozoa from
patients with obstructive azoospermia by microsurgical
epididymal sperm aspiration - MESA or by percutaneous
epididymal sperm aspiration - PESA. MESA - microsurgical
sperm aspiration is performed under general anesthesia and
PESA - percutaneous needle aspiration under local anesthesia
. When epididymal sperm aspiration is performed , frequently
is observed that enough motile epididymal spermatozoa
are found.
TESA - testicular biopsy can be
performed under general or local anesthesia by a surgical
open excision biopsy or by fine-needle aspiration.
Testicular spermatozoa can be obtained from patients with
obstructive azoospermia or non-obstructive azoospermia due
to hypospermatogenesis, incomplete Sertoly cell-only
syndrome or maturation arrest, in whom it was impossible to
find motile epididymal spermatozoa .
Even round spermatids can be used to achieve fertilization
and pregnancy which will be relevant in cases of late
spermatogenic arrest. Epididymal and testicular spermatozoa
can achieve consistent fertilization and high rates of
viable pregnancies.
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