From: Rabbi Moshe Sofer
To: Unknown recipient
A woman with uterine prolapse constantly discharges green and white fluids in which red drops invariably appear, making it impossible for her to count seven clean days or be available to her husband. The Chasam Sofer constructs a multi-layered theoretical leniency based on: the principle that blood emerging through a prolapsed uterus is tahor as it is not the normal manner of bleeding; the view that mere liquid flow does not constitute hargashah d'oraysa; and doubt whether the red drops were present from the outset. He issues six practical directives but stresses the ruling is for halachic theory only and requires concurrence from a prominent authority before application.
Source: Shu"t Chasam Sofer YD §145