Female presents to gynaecological OPD with a complaint of cyclical pain, dyspareunia and infertility. The best investigation to establish the diagnosis would be-

Clinical features of infertility, dyspareunia, and cyclical pain (i.e. dysmenorrhea) are highly suggestive of endometriosis and the investigation of choice/ gold standard investigation for the diagnosis of endometriosis is laparoscopy. TVS is the mainstay for evaluating symptoms associated with endometriosis. It is accurate in detecting endometriosis and aids exclusion of other causes of pain. (Endometriosis can be diagnosed by TVS with adequate sensitivity in most settings, if they are 20 mm in diameter or greater), Since TVS is non-invasive wherever a patient comes with such symptoms, it is the first investigation done; however, IOC is always laparoscopy, however, imaging of superficial endometriosis or endometriotic adhesions is inadequate.