Last year's figure accounted for 6.7 percent of all ovarian cancer patients in the country, but the increase rate outpaced that for women in their 50s and 60s, which came to 40 percent and 46 percent, respectively.

South Korean women in their 50s accounted for 31.3 percent of all ovarian cancer patients here, the most in the country.

Experts attributed the surge in the prevalence of ovarian cancer among 20-somethings to social changes in South Korea, such as early menarche and late marriage.

"The risk of developing ovarian cancer increases as ovulation occurs more often," said Kim Kyung-do, a gynecologist at a Kyunghee University Hospital in eastern Seoul. "The high prevalence of ovarian cancer comes as more girls experience their first periods earlier than in the past. A rise in the number of women deferring marriage also seems to be a cause."

South Korean women are getting married and having children at older ages as an increasing number of them work and pursue their careers. Government data, released in mid-April, even showed that slightly over 51 percent of South Koreans do not think they must get married. (Yonhap)