On the basis of the evidence available in this review, no specific conclusion can be made regarding the superiority of one catheter class over another. Further adequately powered studies reporting on clinical outcomes (e.g. live birth rate) are required. Additional outcomes such as miscarriage rates and measures of discomfort need to be reported.
Catheter type does not affect the outcome of intrauterine insemination treatment: a prospective randomized study.
To compare the main outcome of IUI with the Gynetics catheter (Gynetics Medical Products, Hamont-Achel, Belgium) or the Makler cannula (Sefi-Medical Instruments, Haifa, Israel).
                Prospective, randomized study.
                Infertility and endocrinology unit in a university hospital.
                Two hundred fifty-one infertile couples undergoing 784 consecutive IUI treatments.
                Patients were randomly assigned to undergo IUI treatment with either the Gynetics catheter (124 patients) or the Makler cannula (127 patients).
                Primary outcome measures were pregnancy and cumulative pregnancy rates. Secondary outcome measures were the ease of introduction of the catheter, the presence of bleeding, and semen regurgitation after removal of the catheter.
                The use of the Gynetics catheter resulted in similar pregnancy (10.4% vs. 9.7%) and cumulative pregnancy rates (27.9% vs. 26.4%) as compared with the Makler cannula. Difficult introduction of the catheter was more frequent in the Gynetics group than in the Makler group (19.4% vs. 8.0%, respectively), but the frequency of bleeding did not differ between groups. Sample regurgitation was observed more often in the Makler group than in the Gynetics group (49.9% vs. 17.9%, respectively).
                A lower frequency of sperm regurgitation and a higher frequency of difficult introduction was observed when the Gynetics catheter was used. However, there was no significant difference in pregnancy rates with use of either the Gynetics catheter or the Makler cannula.