Abstract

PIP: A metallic spiral IUD was inserted in 1 region of a rabbit uterus and tied to the uterine wall to test its effectiveness in pregnancy prevention. Within 1 week and after 20 days, pregnancy was hindered in the region where the device was present. The action of the IUD was irrespective of its composition. Changes in the uterine mucous membrane were generally absent, and the uterus was without inflammatory findings and without necrosis or atrophy of the glands. In clinical trials a modification of the Graefenberg ring was used. This was termed the "presear-ring" and consisted of the addition of a flat ball in the center of the ring, thus increasing the surface area. When compared with the Graefenberg ring the efficacy of the modified device was increased (5 pregnancies out of 53 vs. 1 pregnancy out of 73 cases, respectively). Insertion of the device was easy and was performed on an outpatient basis. Some gland proliferation was seen but without inflammation. Pregnancy was possible after the ring was removed. The materials used for the ring were gold or silver plated with gold.