Hi there b6 shouldnt change the colour of your urine,thats a sign of dyhdration...i started taking it to
lengthen my
luteal phase,i was taking it all cycle,i just took the one pill,however it made me ovulate late.i would take it after ovulation until your period arrives..it does work.
as for CBEFM i also used this for months now,b6 will not effect your reading,the only thing that will effect it,is fertility drugs.that contain hormones etc in,so you will be fine.