Abstract: A cervical dilator assembly features a captive extraction element in the form of a collar press-fitted over one end of an insertion element made of the self-swelling vegetable stalk laminaria japonica. A withdrawal cord is affixed to the collar, the collar being captively retained in the swollen condition of the inserted dilator element so that pull on the cord causes withdrawal of the inserted dilator element without rupture or tearing thereof. In the preferred form of the invention the collar is fabricated in the form of a migration-limiting disc.

Abstract: A method for making a cervical contraceptive diaphragm provides for fabricating the entire dome assembly in a separate step, thereafter inserting a toroidal spring within a toroidal chamber pre-formed in a flange affixed to the base of the dome structure, the spring being sealed in by a separate sealing process preferably by a thin filament of vulcanizable rubber laid along the flange away from the spring. Local heating of the filament to cure it and seal the flange about the spring provides for a spring not interpenetrated by liquid elastomer during the curing process, resulting in a free floating spring. The method allows the fabrication of structures employing relatively stiff springs of limited radial compliance, so that the diaphragm may be removed from the first forming mold with minimum loss arising from tearing of the lip.