The invention relates to a pharmaceutical composition for relieving pelvic pain or infertility associated with uterine dysrhythmia. The composition includes a locally-administered anti-dysrhythmic treating agent and a bioadhesive extended-release carrier. The composition may be delivered in an extended release formulation that includes a bioadhesive, water-swellable, water-insoluble, cross-linked polycarboxylic acid polymer, such as polycarbophil. The treating agent may be a local anesthetic, such as lidocaine. The invention also relates to a method of treating or preventing pelvic pain, or treating or improving infertility, by inserting a mixture of an anti-dysrhythmic treating agent and a bioadhesive carrier into the vagina of the patient to be treated.