Ruth -

Oooh, your comment makes *lots* of sense to me!  Does it to anyone else?  A
side effect of let-down (which, after all, is oxytocin release) is thirst -
as if your body is suddenly wanting whatever liquid is available.  If you
haven't drunk enough, **that's** when your body is going to let you know
it.  So that's when the headache would strike, only to be erroneously tied
to prolactin rather than oxytocin!  Which would explain why women don't get
"prolactin-related headaches" during pg, when prolactin is ultra-high!

Diane Wiessinger, MS, IBCLC, LLLL  Ithaca, NY