Maybe it's not a peroid.ovulation thing. I only have a period maybe 4 times a year (very irregular- always have been)and I can only get weight off every second week too.
The menus are the same, the workouts are the same etc. Every odd week I stay the same or gain 1 lb, every other week I am down 3 or 4 lbs!
I think my body just holds unto the fat cells until the last possible moment- whereas some people's bodies give them up easier
who knows, but as long as I average good, it doesnt really matter I suppose
Just hard on the off weeks when I know I've kicked butt and to see the scale stay the same.