Insemination is often used to treat
couples with unexplained infertility – it is inexpensive and less
invasive compared with in vitro fertilization (IVF).
Traditionally, artificial insemination has been
associated with the deposit of sperm in the endocervical canal
[Cervical Artificial Insemination (CAI or just AI)]; however new
techniques of sperm preparation make it possible to concentrate
progressively motile normal spermatozoa free of seminal plasma and
to inject them into the different segments of the reproductive
tract. Some studies have been conducted to evaluate the improvement
obtained by using different techniques and sites to deposit the
gamete preparations: such as the fallopian tube [Gamete
Intrafallopian transfer (GIFT)] or the peritoneal cavity [(Direct
Intraperitoneal Insemination (DIPI)].
Most infertility
clinics in the US currently use the standard technique of Intra
Uterine Insemination (IUI), where sperm are placed inside the
uterus. Pregnancy
rates in those clinics vary depending on the way the insemination is
performed, the type of ovarian stimulation (Clomid or injectable
gonadotropins, with or without GnRHa), the quality of the gametes
and the cause of infertility. Age of the woman and luteal phase
efficiency (or deficiency) are also major factors contributing to
the success of the treatment. Unfortunately, those IUI success rates
have been much lower than with IVF.
Fallopian Tube Sperm Perfusion (FSP)
is a relatively recent modification of IUI
in which the insemination will directly place sperm into the
fallopian tubes. It is thought that insemination with FSP may
yield higher pregnancy and live birth rates for couples with
unexplained infertility. The FSP was first described by Kahn in
1992, with very encouraging results (Kahn et al.
1992). Since 1992 different studies
have examined the best indications for FSP.
Theoretically, the direct
passage of the sperm preparation trough the fallopian tubes
increases the concentration of capacitated sperm in the ampullary
portion of the tube. By placing
spermatozoa in close apposition to the oocyte we can enhance
sperm-egg interaction, fertilization, and pregnancy rates.
In fact, some studies indicate that pregnancy
rates with FSP are twice or
thrice
as high as with IUI (Fanchin
et al.).
At CRH, we do
inseminations using this FSP technique
or
intrauterine tubo-peritoneal insemination (IUTPI).
The main technical difference
between FSP and IUI is that the sperm preparation volume is
increased in FSP. Furthermore, cervical reflux is
prevented by using special designed catheters or a cervical clamp
double nut bivalve speculum during the insemination. Thus, with FSP
the intrauterine pressure is increased and the
sperm preparation is used to perfuse
the fallopian tubes.
This technique is more
complex than a standard insemination, but we feel it is more
effective.
We
recommend
FSP
for the treatment of mild to moderate male infertility, ovulatory
dysfunction, unexplained infertility and infertility due to non
immunological mucus insufficiency.
FSP shows promising results and we have used the same sperm
perfusion protocol for other indications such as donor insemination
with good results.
Bibliography
-
Fanchin
et al., A new system for Fallopian tube
sperm perfusion leads to pregnancy rates twice as high as standard
intrauterine insemination. Fertil Steril. 64
(3):505-10, 1995.
-
Kahn et al., sperm perfusion. First clinical
experience. Hum Reprod. 7-Suppl
1:19-24.1992.
