A Japanese activist who advocates female empowerment was among 10 women from 10 countries awarded this year's International Women of Courage Award, the U.S. State Department said Tuesday.

Sayaka Osakabe was commended for her fight against "maternity harassment," or unfair treatment of pregnant working women, which led to a first-ever ruling by Japan's top court last year that demotion due to pregnancy is illegal in principle.

"Ms. Osakabe's courage to speak out has spurred government and civil society action, including the government of Japan official notice on Jan. 23, 2015 that dismissals and demotions of pregnant women are presumed illegal," the department said.

Osakabe was harassed and pressured to resign from her job after becoming pregnant and suffered two stress-related miscarriages. She founded Matahara Net to speak up on behalf of pregnant women and young mothers who are bullied at work.

Their plight has spawned a new term: matahara, a hybrid contraction of the term "maternity harassment," which became a buzzword in Japan in 2014.

The department will hold an award ceremony on Thursday with first lady Michelle Obama in attendance.

The United States established the award in 2007. The other recipients this year include May Sabe Phyu, director of the Gender Equality Network in Myanmar, Nadia Sharmeen, a journalist in Bangladesh, and Tabassum Adnan, founder of a nongovernmental organization in Pakistan.