Tubal sterilization with a waterborne polyethylene glycol in situ cross-linking material: A minimally invasive approach

Objective: To assess the effectiveness and compatibility of an in situ-gelling polymeric device when implanted in the fallopian tube to prevent pregnancy. Design: Controlled laboratory study. Setting: Animals in a controlled laboratory environment. Animal(s): Ten white New Zealand rabbits (nine female and one male). Intervention(s): The material was implanted through a small incision into one of each rabbit's twin fallopian tubes. The rabbits then were allowed to heal. After a healing period of 6 to 10 weeks, the rabbits were bred. After breeding, the animals were killed, and samples were collected from their fallopian tubes for histology. Main Outcome Measure(s): Pregnancy of the specimens. Result(s): Four specimens showed unilateral pregnancy (pregnancy in only one uterus). Because rabbits have the capacity to be pregnant in both uteri simultaneously, this suggests strong potential of the material for use as a contraceptive. Conclusion(s): Although concerns remain concerning distension and potential injury resulting from use of the system, enough data have been gathered to warrant further study of this material for use in humans.