Is plastic surgery effective to improve keloid C-section scar?

It can be, but . . . Keloids are more rare than hypertrophic scars and they're also much harder to treat. Proper treatment begins with a correct diagnoses of the type of scar. There are treatments for both! Hypertrophic scars respond better to treatments and to surgery, but keloids can also be treated with excision accompanied by corticosteroid injections. There are a number of emerging therapies as well. https://www.cosmeticsurg.net/blog/2016/03/24/keloids-hypertrophic-scars-in-plastic-surgery/
Yes! Yes, surgery is an excellent option for improving your Cesarian section scar. I strongly recommend that you seek consultation with a board-certified plastic surgeon. Good luck!
Yes. It is more likely that you have a "hypertrophic scar" rather than a "keloid scar." both can be helped by plastic surgeons who have many options available to them (both surgical and non-surgical) to improve the scar. Under the microscope both the hypertrophic and keloid scars look alike and their treatment is similar. Consult with a plastic surgeon to learn your options.

Related Questions

In what way can you make a c-section scar look better if you have keloid skin?

Steroid injections. Keloids can sometimes respond to being injected with steroids. The sooner they are injected the better chance there is to reverse the keloid process. Otherwise, surgical revision is the only other option. Read more...