Abstract: An intravaginal pessary for treating prolapses includes a flexible core having a longitudinal axis and being disposed in a three dimensional configuration. The longitudinal dimension of the core along its longitudinal axis is modifiable within limits by manual pressure, both before and after insertion of the pessary into a vagina, the core being non-resiliently expandable and contractible within limits to modify the longitudinal dimension. A first longitudinal portion of the core is meshingly engageable with a second longitudinal portion of the core intersecting the first longitudinal portion of the core to lock within limits the longitudinal dimensions of the core intermediate the first and second longitudinal portions. The first and second longitudinal portions are manually separable, both before and after insertion of the pessary into the vagina, to unlock the longitudinal dimension of the core intermediate the first and second longitudinal portions.