Objective: To verify, the effectiveness of desensitization exercises w
ith dilators in the treatment of vaginismus, while comparing 2 therape
utic variations with differing instruction procedures (''in vivo'' ver
sus ''in vitro'') during the desensitization exercises. Method: A cons
ecutive random sample of 44 female outpatients in sexual therapy were
divided into groups for either treatment on a random basis. All patien
ts were treated until the symptoms abated on the basis of a structured
therapy program. The stability of the therapeutic success was verifie
d through follow-up interviews. Results: Forty-three (97.2%) of the pa
tients were able to have sexual intercourse after an average of 6.3 th
erapeutic sessions. One-third reported an increase in their sexual des
ire. Thirty-four of 39 patients (87.2%) would be prepared to repeat th
e therapy. There were no significant differences in the success and th
e required number of consultations for the cure between the 2 groups i
nvestigated Conclusions: Desensitization through exercises with dilato
rs is an effective method for treating vaginismus. The choice of instr
uction procedure can be left to the patient.