hmm..i also sometimes use VCF along with my bc...my bf has no clue i do and it doesn't irritate me at all, though i've heard that it could....maybe go once or twice without using it and see if the same irritation occurrs, and if not then you're pretty safe to say its the VCF..however if some irritation still occurrs then you should probably get checked out....if it is the VCF maybe you could look into a different spermacide?