Abnormal periods after cryotherapy on cervix? I had cryotherapy in July and ever since then, my periods have been very dark brown, thick, and only last a couple of days. Before cryo my periods were normal, red, started on wednesdays and ended on saturdays. I'm just concerned and I'm away from home and won't be able to go to my gyno until December. Just curious if this has happened to anyone else and also worried that the cryo has messed with my fertility.