Out Door Fitness for Pregnant Mommy

Google: Baby Boot Camp San Francisco. Most Baby Bootcamp classes are for moms w/ babies/toddlers, but a few are for while you're pregnant. Also, you can probably continue with your boot camp until you get big. You can pretty much do the same exercise when you're preg as when you're not, until size limits you (with a few exceptions, of course).

Stroller Strides- two locations in SF and an awesome workout!

I haven't done them myself, but check out Stroller Strides. Just as I was going to try them myself, I was told to take it easy, then when I was given clearance to walk again, I developed plantar fascitis...grrr.

http://www.strollerstrides.com/

Stroller Strides - the woman in charge in SF is Jen Stoneman. She's really terrific.

Also, Baby Boot Camp. They have a prenatal class. I found Baby Boot Camp classes when my oungest was just a few months old & LOVED it! I wasn't much of a runner before (you don't have to run at the cardio bits) but started liking it & it got me in GREAT shape. And I made a few good frineds as did my son.