PIP: 39 women using the Lippes loop C, and complaining of chronic pelvic pain dating from after insertion of the IUD, were investigated by laparoscopy and transuterine pelvic venography in the premenstrual period of the cycle. Patients complaining only of cramp-like pain similar to spasmodic dysmenorrhea were not included. Other types of pain noticed were dull aching low abdomen, deep seated pelvic pain with associated dyspareunia, and low backache mainly on the sacrum. Pain was attributed to the presence of pelvic variocele diagnosed by laparoscopy (52%), and venography (95%), chronic pelvic inflammatory disease (28%), and pelvic adhesions (8%). The sites of maximum pain correlated well with the sites of maximum varicosities and/or venous stasis. Menorrhagia was associated with pain in one-third of the cases and was explained on the basis of increased pelvic vascularity, chronic pelvic inflammatory disease, and cystic changes in the ovaries. The possible factors predisposing to uterine perforation during venography in 3 cases are discussed.