Intrauterine capsules for incubation of gametes and subsequent release of embryos.

In order to obtain incubation in uteri of spermatozoa, oocytes, and embryos, for treatment of patients referred for in vitro fertilization, a capsule was produced which could contain the human gametes and allow human fertilization and embryo growth after intrauterine introduction. Agar was chosen for capsule material and a mold was constructed for the production of capsules. The material was tested in vitro using mouse embryos and human oocytes and sperm. Intrauterine resolution was tested on mice and by insertion on 11 women. Empty capsules were inserted into the uterine cavity in 15 cycles the day after the luteinizing hormone peak and followed by daily ultrasound examinations. The resolution time was adjusted by changing the wall thickness of the capsules. The final type was dissolved after 3 to 4 days. No complications were observed and capsules could be inserted on all occasions. The major problem was expelling of capsules, which occurred in seven cycles. The problem seemed to be solved by the administration of indomethacin at the day of insertion.