Not sure if this will help as I don't have PE, just high BP (my wee is fine as is blood).
Ob. said if my BP gets to 170/110 during labour then they'll 'treat' it (I didn't ask what this treatment was, I'm assuming a shot in the thigh with something?) and if it gets to 200/120 then we'll be looking at vaccuum/forceps or an emergency c.sec.
My BP has been around the 140/90 mark for the last three weeks which is annoying, but it's not yet high enough to mean a high risk labour.....
Good luck at any rate!