Japan had 303,268 doctors as of the end of 2012, topping the 300,000 threshold for the first time since officials began compiling comparable data in 1954, with women accounting for almost 20 percent, the health ministry said.

The ratio of women set a record at 19.7 percent, according to a survey conducted every two years.

The total for both men and women grew 2.8 percent, while the percentage of women increased 6.7 percent, the Health, Labor and Welfare Ministry said Tuesday.

"The number of doctors is expected to keep growing thanks partly to an increased enrollment capacity at medical schools, but the tendency for regional disparity has not changed," a ministry official said.

By prefecture, Kyoto had the most doctors per 100,000 people, at 296.7, followed by Tokushima at 296.3 and Tokyo at 295.7. Saitama had the fewest, at 148.2, followed by Ibaraki at 167.0 and Chiba at 172.7. The availability of doctors was below the national average of 226.5 in the Tohoku and Chubu regions.