A detail of a tampons box is seen in London, Britain March 18, 2016. REUTERS/Stefan Wermuth

Chen Xiexia of China sings the national anthem after receiving her gold medal for the women's 48kg Group A weightlifting competition at the Beijing 2008 Olympic Games August 9, 2008. REUTERS/Oleg Popov (CHINA)

Tokyo governor Yuriko Koike waves the Olympic flag as she walks out of a plane during a ceremony to mark the arrival of the Olympic flag at Haneda airport in Tokyo, Japan, August 24, 2016. REUTERS/Kim Kyung-Hoon

Tokyo governor Yuriko Koike (R) waves the Olympic flag as she walks out of a plane during a ceremony to mark the arrival of the Olympic flag at Haneda airport in Tokyo, Japan, August 24, 2016. REUTERS/Kim Kyung-Hoon

Flight attendants wave Japan's national flags while they wait for the arrival of the Olympic flag during a ceremony to mark the arrival of the flag at Haneda airport in Tokyo, Japan, August 24, 2016. REUTERS/Kim Kyung-Hoon

TV cameramen are silhouetted while they wait for the arrival of the Olympic flag during a ceremony to mark the arrival of the flag at Haneda airport in Tokyo, Japan, August 24, 2016. REUTERS/Kim Kyung-Hoon

Tokyo governor Yuriko Koike (L) and Japan's Olympic team's sub-captain Keisuke Ushiro carry the Olympic flag (L) and JOC flag during a ceremony to mark the arrival of the Olympic flag at Haneda airport in Tokyo, Japan, August 24, 2016. REUTERS/Kim Kyung-Hoon

Tokyo governor Yuriko Koike (R) and Japan's Olympic team's sub-captain Keisuke Ushiro wave the Olympic flag (R) and JOC flag during a ceremony to mark the arrival of the Olympic flag at Haneda airport in Tokyo, Japan, August 24, 2016. REUTERS/Kim Kyung-Hoon