Mother-to-be Katie Yung was 35 weeks into her pregnancy and counting down to giving birth when she learned she had a potentially life-threatening condition.Her doctor told her she had severe placenta previa, which can cause severe bleeding during childbirth, and she might need a blood transfusion to avoid complications that could lead to a stroke or even death.Red Cross in urgent blood donors appeal as supplies dwindleWith blood stocks running low in Hong Kong because of the coronavirus…