A Tokyo medical school systematically cut women applicant's entrance exam scores for years to keep them out and boost the numbers of male doctors, Japanese media said on yesterday.

Prime Minister Shinzo Abe has made creating a society "where women can shine" a priority, but women still face an uphill battle in employment and hurdles returning to work after having children, despite Japan's falling birthrate.

The exam score alterations were discovered in an internal investigation of a graft allegation that emerged this spring over entrance procedures for Tokyo Medical University, the Yomiuri Shimbun daily said.

From 2011, it said, the university began cutting the scores of female applicants to keep the number of women students at about 30 percent, after the number of successful women entrants jumped in 2010.

The paper quoted university sources as saying the action was prompted by a "strong sense at the school" that many women quit medicine after graduating to get married and have children.

Tokyo Medical University spokesman Fumio Azuma said an internal investigation had already begun after allegations this spring of bribery involving the medical school admission of the son of a senior official of the education ministry.

"Of course, we will ask them to include this in their investigations," he said, adding that the results of both investigations could come as early as this month.

Social media erupted in anger at the reports, with some posters demanding more steps to ensure equality while others said similar things were happening everywhere.

"It feels as if the earth's crumbling under my feet," wrote one. "Who are you kidding with 'Women should play an active role'?"

Another said, "Women are told they have to give birth; if they don't, they're mocked as being 'unproductive', but then again, just the possibility that they might give birth is used to cut their scores. What's a woman supposed to do?"