There are international stereotypes relating to breast augmentation.
Americans like the breast big and the butt small.
Brazilians like the breast small and the butt big
Europeans like somewhere in between.
What about Asia? Well traditionally they weren't even part of the discussion as breast augmenatation was fairly limited outside of Japan. As the economies of Asia & Southeast Asia have grown, the #'s of elective cosmetic surgery procedures has been growing at a staggering rate.
For decades, the Chinese government forbade cosmetic surgery, seeing it as a reflection of despised western values. Only 20 years ago, plastic surgery expertise was restricted to a small number of doctors specializing in traumatic and cancer reconstructive surgeries. According to figures from the PRC government, at present the Chinese now spend 2.4 billion USD a year(!) on cosmetic surgery, with an estimated 1 million operations performed a year. The Japanese spend over 2 trillion yen (18.7 billion USD) on cosmetic surgery each year. South Korea's Seoul is now home to over 2,000 private clinics, with surveys suggesting that at least 50 percent of Korean women in their twenties have experienced some form of plastic surgery -- an estimate some call conservative. (The bulk of the proceding paragraph came from this article in Zee News)
As the average Asian woman is smaller in frame then those of western Euorpean, African, or Latin descent the sizes of implants were naturally somewhat smaller. However, as the tastes & expectations of the west are permeating the east via media and pop culture, trends in cosmetic surgery are also reflecting the American ideal.
At the plastic surgery clinic BARAM in South Korea surgeons say the size of breast implants has doubled from 135 cc on average in 1994 to 265 cc in 2003. BARAM clinic chief Sim Hyung-bo points out the obvious that “One way to tell augmented breasts with the naked eye is that it is safe to say that skinny women with very large breasts probably had them enlarged. It is true that Koreans’ physique has changed remarkably over the years, but their breasts are still smaller than those of Westerners.”
135 cc implants! Those aren't even commercially available in the United States & Europe except by special order. A survey a few years back in one of the Plastic Surgery trades had the average size of implant somewhere around 350cc. Discussions between Plastic Surgeons would seem to indicate that the "average" augmentation in some peoples practices has crept up over the 400-425cc range.
For a related post on implant sizes & the consequences thereof see"How big is too big?"