Vaginismus can be primary or secondary.
Primary vaginismus refers to cases where the girl had the reflex from the beginning: the first time she tried to insert a finger, tampon or/and the first time she tried intercourse.
Secondary vaginismus refers to girls who were able to have intercourse without any problem, but who developed this spasm later on.
With secondary vaginismus it’s often possible to find out what caused it. What you need to do is going back in time, looking for event(s) or feelings that preceded the first vaginistic response. This is important: when you know what caused it you can solve the problem more easily.