But a World Rugby spokesman says there is no new evidence to challenge the current position.
England and Saracens number eight Billy Vunipola tells BBC Radio 5 live he would take a pay cut to play less rugby.
Centre Rob Horne is delighted to "get the monkey off the back" after scoring his first tries for Northampton Saints.
England and Saracens number eight Billy Vunipola will be out for the next four months with a knee cartilage injury.
Audio & Video
England scrum-half Ben Youngs says the number of games at the moment is "at the limit".
Adam Harrison's life hit rock bottom because of bullying over his weight and sexuality. It was going to take something special to transform him... enter rugby.
Ed Jackson, his father Mark and fiancee Lois chart his progress from life-threatening paralysis in hospital to walking and making plans for his wedding in 2018.
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