Transcatheter tubal sterilization in rabbits: Technique and results

RATIONALE AND OBJECTIVES. A potential method of nonsurgi-cal tubal sterilization was tested in rabbits. METHODS. Metal coils were designed which could be placed into the uterotubal junction using transvaginal fluoroscopic fallopian tube catheterization. These metal coils were successfully placed unilaterally in the uterotubal junction of 32 rabbits. The contralateral fallopian tube and uterus were used as a control. The rabbits were bred, and the presence of pregnancies was confirmed by palpation. RESULTS. In 21 rabbits (66%), the coil stayed in place. Sixteen rabbits had multiple gestations on the side without the coil and no gestations on the side with the coil. Three rabbits had gestations on both sides, even though the coil was in place, and two rabbits never conceived. In 11 rabbits (34%) the coil was dislodged as early as 5 days and as late as 18 weeks after the procedure. Five of these 11 rabbits had bilateral embryos, 4 had embryos only on the side contralateral to where the coil had been, and 2 never conceived. CONCLUSIONS. The metal coil does prevent conception if it stays in place at the uterotubal junction. However, the coil failed to prevent pregnancy in 3 of 19 rabbits, and was dislodged in 11 rabbits, giving an overall failure rate for contraception of 44%.