It *is*variable.  I start with water gain weight (and PMS symptoms) immediately
folllowing ovulation/mid-cycle.  When I was doing WW, my weight progress always
looked like this:

Day 1 (of cycle, when I start my period) to Day 7:  loss of 8-9 lbs.

Day 8 to Day 14:  loss of 2 lbs.

Day 14 to Day 21:  no loss

Day 21-Day 28: gain of 4-5 lbs.

So, I while I would have a net loss of 5 to 6 lbs. a month, it would show up in
the first two weeks of my cycle.  As soon as I hit mid-cycle, it was covered up
by the TOM gain.

I'm kind of struggling with that now, in my second week of this.  I lost 5 lbs.
the first week low-carbing, and nothing the second week.  BUT, I'm trying not
to get frustrated, because it is also the third week of my cycle, where I've
NEVER lost anything.  I had hoped that low carbing would have an effect on my
cycle, but it doesn't appear so.  So, I'm going to have to be patient and wait
for two more weeks, and see what happens.  

Sheila