Department of Obstetrics The Third Affiliated Hospital of Sun Yat-sen University Guangzhou China;
Department of Obstetrics The Third Affiliated Hospital of Sun Yat-sen University Guangzhou China;
Department of Obstetrics The Third Affiliated Hospital of Sun Yat-sen University Guangzhou China;
Department of Obstetrics The Third Affiliated Hospital of Sun Yat-sen University Guangzhou China;
Department of Obstetrics The Third Affiliated Hospital of Sun Yat-sen University Guangzhou China;
Department of Obstetrics The Third Affiliated Hospital of Sun Yat-sen University Guangzhou China;
Prenatal Care; Exercise; Bed Rest; Preterm Birth; Psychological State;