I get the numbness but not necessarily with weight loss. Every once in awhile the scar area will get sore, too, even though I'm told you can't see the scar.

This isn't for just C-sections (I haven't ever had one), but a general "to do" that my doctor suggested after my latest surgery (knee), also suggested for my husband when he had surgery on his shoulder. It's for after the scab has gone and you've got a scar, if you experience numbness:

"Place your fingertips gently against the scar, with or without lotion, and make small circles (roughly 1cm in width) over the numb area. If you feel a thickness in the scar tissue, spend more time gently massaging that area. It may cause some mild discomfort, but it shouldn't be painful or cause swelling when you are finished. If you experience pain, swelling, or your skin is hot to the touch, or red, please contact your doctor."

(This is translated from Danish, so the wording isn't perfect, and google translate was worse...)

Off topic, (re: google translate) I just watched a clip of Anne Hathaway and Jimmy Fallon singing a song, translated to another language, and then translated back to English again. Very funny.