Clinical evaluation of the multiload intrauterine device 'CU'250 standard - Bozzini, N; Markos, M; Trivelatto, S A; Freitas, S R M S; Evangelista, L P; Melo, N R; Hegg, Roberto; Grassioto, O R; Bastos, Alvaro da Cunha; Pinotti, José Aristodemo (World Congress of Gynaecology and Obstetrics (Figo), 1991)