Prolonged prothrombin time in hyperemesis gravidarum as an indicator of vitamin K deficiency. - Ouchi N; Kuwabara Y; Yonezawa M; Ogawa J; Kasano S; Kato M; Kurashina R; Ichikawa T; Kawabata I; Suzuki S (The journal of obstetrics and gynaecology research, 2025)