get off at
get off at (some place)
euphemism To use the withdrawal method of birth control. The place named after "at" can be any railway station that comes just before the end of the line. Primarily heard in UK. You know, there's still a chance she'll get pregnant even if you get off at Chalfont and Latimer.
get off at —practise birth control by the withdrawal method. informal euphemistic
The open slot in the phrase is filled by the name of any of a range of railway stations (e.g. Clapham Junction in London, Paisley in Glasgow) immediately preceding a terminus.