Is the fallopian tube better than the uterus? Evidence on intrauterine insemination versus fallopian sperm perfusion


Insemination, IUI, FSP, unexplained infertility, non-tubal infertility

A. SUNDE 1, J. A. KAHN 2

1Fertility Clinic, St. Olav’s University Hospital in Trondheim, N-7006 Trondheim Norway.
2Fertility Clinic, Telemark County Hospital, N-3901, Porsgrunn, Norway.

Correspondence at:


Fallopian tube sperm perfusion (FSP) is in short comprised of mild ovarian stimulation with the aim of maturing 2 follicles, ovulation induction and insemination using a large volume (4 ml) of inseminate. Perfusion studies demonstrated that with this large volume, the inseminate will fill the uterine cavity, flow through the fallopian tubes and some of it will end up in the peritoneal space. The rational being that this maximizes the chances the gametes will meet and fertilization occur.
We initiated a prospective randomized study that showed that FSP gave higher pregnancy rates compared to conventional intrauterine insemination (IUI), OR: 4.1, (1.2-13.4 95% Confidence interval).
In our hands, FSP seems to give the best results in couples with unexplained infertility.
In the years 1990 to 2002, 1005 inseminations with husband’s semen were carried resulting in 141 pregnancies and 112 deliveries. In the same period, 1200 inseminations with frozen donor semen were carried out giving 333 pregnancies and 226 deliveries.
Several studies from other research groups have tried to elucidate whether FSP or IUI will give the highest pregnancy rates in the treatment of non tubal/unexplained infertility. Most of these studies are rather small. A complicating factor is that in these studies, different protocols, different utensils and different catheters for performing FSP have been used.
This may well have influenced the outcome of the studies and contributed to the fact that currently there is no consensus on whether FSP or IUI is to be advocated.