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.
