What Causes Painful Urination In The Partner After Using Today's Sponge?

Hello....My boyfriend and I have been having unprotected sex......I was on the pill but stopped taking them and instead I used a Today's Sponge for the first time...and afterwards my boyfriend complained of burning when attempting to urinate....But why??....I haven't been with anyone else so I'm not worried on my end..but concerned for him...HELP PLZ!!!!