A Japanese artist known for her work depicting female genitalia pleaded not guilty on Wednesday to a charge of obscenity as she called on Japan to stop treating the subject as a shameful taboo.

Taking the stand at the first session of her Tokyo District Court trial, Megumi Igarashi, 43, said she is fighting the charge to challenge Japanese society's widely held belief that female genitals were "dirty," "shameful" and "abhorrent."

"For all these years, I have continued to proudly say aloud the word 'manko' because that is an important part of my body," Igarashi said in her opening statement, referring to the Japanese slang for "vagina."