|
|
NON-SURGICAL ALTERNATIVES FOR MEN DESIRING
CHILDREN FOLLOWING A VASECTOMY
by Michael Feinman, M.D., F.A.C.O.G.
Board Certified, Reproductive Endocrinology and Infertility
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 epididymis 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 longstanding 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 In-vitro fertilization (IVF),
represents an excellent alternative to vasectomy reversal. The original microsurgical
approach is known as “Microsurgical epididymal 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 epididymal 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 epididymis, 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.
|