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Non-Surgical
Alternatives For Men Desiring Children Following A
Vasectomy
Michael
Feinman, MD, FACOG
Board
Certified, Reproductive Endocrinologist
In the
late 1980's, Dr. Sherman Silber in St. Louis, proved
that sperm obtained directly from the scrotum could
be used to successfully fertilize eggs and achieve viable
pregnancies. While this procedure was originally intended
for men who are born with an obstruction in the genital
tract (congenital absence of the vas deferens), it has
become clear over the past decade that men with previous
vasectomies can benefit from similar procedures as well.
The development and maturation of
sperm occurs in the testes. The testes also produce
most of the testosterone in men. The sperm begins its
trip through the male ducts in an enlarged portion of
the ducts called the epididymis. This duct eventually
becomes the vas deferens (vas). Along the route of the
vas, the prostate and seminal vesicles add the fluid
portion of the ejaculated semen. When a vasectomy has
been performed, the vas deferens is blocked before the
area where the seminal vesicles add the fluid. That
is why these men still produce semen, but no sperm.
Dr. Silber microsurgically removed sperm from the epididymus
and achieved viable pregnancies through assisted reproductive
procedures, thus proving that sperm do not have to make
the trip through the ducts to achieve fertilizing potential.
Vasectomies represent an important and effective method
of "permanent" birth control. For a variety
of reasons, a small percentage of men who have a vasectomy
later desire more children. Until recently, if semen
was not frozen at the time of the surgery, microsurgical
reversal of the vasectomy has been the only option for
these men. Vasectomy reversal has several disadvantages,
however.
Vasectomy reversal represents major
surgery of the scrotum. Most men with long-standing
vasectomies develop sperm antibodies that may inhibit
fertilization, even if the reversal procedure is surgically
successful. Finally, reversals done more than 7 years
from the original procedure are associated with very
poor pregnancy rates. Unfortunately, many men seeking
fertility after a vasectomy fall into this last category.
Removing sperm directly from the
scrotum, combined with IVF, represents an excellent alternative
to vasectomy reversal. The original microsurgical approach
is known as "Microsurgical epydidimal sperm aspiration,"
or "MESA."
This procedure produces enough sperm to freeze for future
use. However, like vasectomy reversal itself, the procedure
involves major surgery of the scrotum, is relatively
expensive, and can often only be performed once on each
side because scar tissue hinders the ability to find
the duct on subsequent attempts.
Over the past few years, HRC doctors
have developed two non-surgical alternatives to MESA.
The first approach is called, "Percutaneous epydidimal
sperm aspiration," or, "PESA." The second
alternative is called, "Testicular sperm extraction,"
or, "TESE." Both procedures can be done using
local anesthesia. With PESA, a small needle is guided
through the skin into the epydidimis, and a small amount
of fluid containing sperm is aspirated. In contrast,
with TESE, a small amount of tissue is directly removed
from the testis using a small biopsy needle. In either
case, relatively small numbers of sperm are obtained,
and these can fertilize the female partner's eggs through
Intracytoplasmic
sperm injection (ICSI), where individual sperm are
actually injected into the eggs. None of these procedures
produce enough mobile sperm for simple artificial inseminations.
Potential complications of the non-surgical
procedures include infection and bleeding. Bleeding
under the scrotal skin can theoretically cause the formation
of a painful blood clot known as a hematoma. In over
5 years of performing these procedures, we have not
seen either of these complications.
Before proceeding with any of these
treatments, the male partner should be evaluated by
the person who will perform his procedure. An appropriate
history and physical examination should be performed,
focusing on potential factors that could impact on likely
successful aspiration of sperm. The physical exam can
identify potential problems that might be encountered
and can help the physician estimate the likelihood of
finding adequate amounts of viable sperm. We measure
serum levels of testosterone and FSH in the men to make
sure they are producing enough hormones to sustain normal
sperm development.
As with routine IVF cycles, the
female partner uses injectable hormones to both stimulate
multiple egg production and to control the timing of
ovulation. The egg retrieval is done vaginally, using
an ultrasound probe to guide a needle into the ovaries.
This procedure can be done with local anesthesia, or
with conscious sedation. The PESA or TESE is done on
the same day, and the eggs are inseminated shortly after
the conclusion of both procedures. Three days later,
a small number of embryos are inserted through the cervix
into the uterus. The number of embryos transferred depends
on the age of the woman and the quality of the embryos.
Extra embryos can be frozen for future use. Over the
past year, the doctors at HRC have been addressing the
issue of multiple births by transferring lower numbers
of embryos in younger patients. We can do this, in part,
because of the quality of our freezing program, giving
couples a realistic second chance.
The choice of procedure is
largely dependent on physician preference. All three
variations of the male procedure are available at HRC.
Over the past several years, we have experienced a 20-30%
ongoing pregnancy rate with non-surgical sperm extraction
procedures. The success rates vary, based on various
factors, maternal age being one of the most important.
We believe, that for couples in whom the male partner
has a vasectomy more than 7 years old, these success
rates following single procedures are greater than the
overall success rates with vasectomy reversal. For younger
women, the overall success rate following the initial
combination of
PESA/ TESE and IVF,
is enhanced if there are frozen embryos available for
another embryo transfer.
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