Serum levels of CA125 turned out to be a valuable parameter not only as a marker of ovarian carcinoma but also in other fields of obstetrics and gynaecology. Up to date most of the studies dealing with the subject remain experimental and their clinical usefulness is not widely acknowledged. Accessible and relatively cheap tests measuring the serum level of this antigen together with its proven clinical value might contribute to a more frequent and much wider use than it takes place contemporarily.