Periods are the final taboo for women in sport, according to Britain's former number one female tennis player Annabel Croft.
Croft was speaking after the current British female number one tennis player, Heather Watson, alluded to periods when discussing her defeat in her opening match in the Australian Open.
Watson, 22, called a doctor to the court during the match because of illness. In a post-match interview with BBC sport she said she was feeling "bloated and weak" and blamed "girl things". "I'm going to go and see the doctor afterwards and see if there's anything I can do to help with times like these in the future," she added.
Speaking on Radio 5 Live, Croft said periods were "swept under the carpet and a big secret" in society.
I can tell you there will be an awful lot of your female listeners out there who will be able to identify completely with what Heather Watson was basically alluding to.
She was dealing with bloating, dizziness, exhaustion, women get highly emotional at this time, they are often tearful they are not always rational in their decision making. It's pretty understandable and extremely unlucky that it has happened at one of the biggest events for her in the calendar year.
Ruth Holdaway, the chief executive of Women in Sport said in a statement: "It is important that sport understands and is sensitive to the potential impacts of the menstrual cycle for female athletes. This is not an issue that should be taboo for sport and is undoubtedly a subject which would benefit from greater understanding and openness."