If you've upped your exercise recently you'll find your sweat reflex will switch on more readily. Your body has gotten used to you being active so you will tend to break into a sweat at the slightest thing like climbing a flight of stairs. So you'll need to drink more than before, even on days when you don't work out.
Many people also report feeling warmer while losing weight. Possibly because when you are leaner you get more brown fat cells which burn excess energy as heat.
Healing will also use up more water as well as nutrients. If you ate SAD before you went Primal then you probably have some inflammation that is still healing, and pregnancy will also have depleted a lot of stored nutrients. I wouldn't recommend a multivitamin (I personally think they are a con), but you may benefit from supplementing some things like fish oil, vitamin D and magnesium; and/or upping your intake of the foods I would consider as the best superfoods for mums - such as liver, dark greens, fish, egg yolks, oh and sunlight!
Start weight: 238 lbs (March 2012)
Current weight: 205 lbs (July 2012)
Loss so far: 33 lbs!!!
WOE: Primal + IF
Movements: Hiking, sprinting.
Goal: to see my abs some time in 2013!