Reference range for uterine artery Doppler pulsatility index using transvaginal ultrasound at 20-24w6d of gestation in a low-risk Brazilian population - Peixoto, Alberto Borges; Caldas, Taciana Mara Rodrigues da Cunha; Tonni, Gabriele; Morelli, Priscilla de Almeida; Santos, Larissa D'amico; Martins, Wellington de Paula; Araujo Júnior, Edward (Journal of Turkish-German Gynecological Association, 2016)