In the field of medical fluid containers there is a need for an improved administration port which allows a user more easily to insert an IV spike and has a reduced tendency to leak following removal of the spike. An administration port (10), for a medical fluid container, comprises a hollow port body (16) which receives an insert member (30). The insert member (30) has an engagement portion (32) which is defined by a cavity (36) and a sealing portion (34) which is defined by a self-sealing membrane (38) that extends across one end (40) of the cavity (36). The self-sealing membrane (38) includes a penetration zone (41) and respective upstream and downstream faces (44, 46). The upstream face (44) includes at least one recess formation (48, 50) that extends around the penetration zone (41).
