Ryoko Tani is hoping to accomplish what no woman has ever done in Japanese sports history, when she aims for her fifth Olympic medal and first as a mother in Beijing in 2008.

News photoFour-time Olympic judo medalist Ryoko Tani announces Monday that she is expecting her first child.

Tani announced Monday she will not compete at the judo world championships in September as she is expecting her first child, but also said that she is nowhere near drawing the curtain on her illustrious career in which she has won two gold and two silver medals at the Olympics.

"I've never heard of a female athlete in Japan who won an Olympic gold after giving birth so I would like to become the first," said Tani, who won her most recent gold at the Athens Games in 2004 in the 48-kg weight class.

"I'm not retiring yet. I'm not taking a break because I'm injured or feel physically unfit. I won an Olympic gold under the name Tamura (maiden name) and also under Tani (married name), and I would to win another as a mother," she said.

The 29-year-old Tani married Orix Buffaloes outfielder Yoshitomo Tani in February 2003, three years after striking her first Olympic gold in Sydney.

She was named as Japan's representative at the world championships after winning the national invitational weight-class championships in April and was expected to take a shot at an unprecedented seventh straight title in Cairo.