Gabi, that's a great observation.  I never thought of that correlation.  But
I had a weird personal experience.  My youngest was 13 mo old when I was to
have repair on my bladder. I breastfed my son last at 0600.  By 9 o'clock I
had a headache from being hypoglycemic and they inserted an  IV to diminish
my headache. It worked but what was so weird is as they bolused me with
fluids, I swear it all went to my breasts because I felt the sudden swelling
 in my breasts.  This was not a refilling or MER.
So when I went to the OR, I told my friends who just happened to be the OR/RR
nurse (small hospital-Guam).  So if this happened again they wouldn't freak
out.
That sounds like a logical explanation because that's what felt this was, a
fluid overload.