Former Wales full-back Dyddgu Hywel believes women's international rugby is being treated unequally compared to the men's game amid the Covid-19 pandemic.
The 2021 World Cup in New Zealand is set to be postponed until 2022 on the recommendation of governing body World Rugby.
The women's Six Nations was delayed until spring while the men's event has gone ahead as scheduled.
"It is really hard to get your head around it," said Hywel.
The World Cup is currently scheduled to be held in New Zealand between 18 September and 16 October with World Rugby saying the "challenging Covid landscape" has influenced its recommendation.
A final decision is expected after the Rugby World Cup board and World Rugby's executive committee consider the recommendation on 8 and 9 March.
The women's Six Nations, which is usually held on the same weekends as the men's Six Nations, takes place in April with a reduced format.
Men's international rugby went ahead in late 2020 with the Autumn Nations Cup replacing the traditional tours by major southern hemisphere nations to Europe while women's Test rugby has been put on hold.
Meanwhile World Rugby's 2021 Sevens series will include five men's and four women's tournaments in 2021.
Hywel told BBC Radio Wales: "What's really disappointing in my opinion is how do the men get an autumn series last year?
"They've got a normal Six Nations this year, which is also great news, but why is the women's game different or treated differently?
"We're still talking about equality in sports and it's 2021. We shouldn't be having this conversation any more and I truly understand the Covid situation.
"But that's the same for everyone. How can the men's game carry on and the women's had delays or cancellations or even a shortened Six Nations, which is happening next month.
"It's just a little bit disappointing."
She added: "Is it money? Is it budget, finance - who knows? But in my opinion it should be treated equally.
"The women's Six Nations should have carried on because the men's had carried on so it's a tricky one and I would like to hear more answers to be honest."
The men's Six Nations teams are operating in bubbles for much of their tournament, while there are few women's full-time professionals apart from England, making it more difficult to take the same medical precautions.
Hywel fears the delay to the World Cup will lead to some leading senior players missing out after planning for the tournament to go ahead as originally planned.
"It is a huge blow and if you think about the World Cup it's the main stage of women's rugby and something you have to wait four years and prep four years for," she said.
"Unfortunately for the women's game we don't have the Lions tour to look forward to between those four years.
"But it's a massive hit and I feel for the players, the coaching staff and maybe those top, experienced players - do they have another year in them for the training, keeping the fitness and obviously women's players are not professional full-time, they've got their career on their hands.
"Maybe you're in a great place at the moment with a World Cup that should have been in six months, your fitness is great and you're injury free.
"Who knows what will happen this time next year?"
However, Hywel also believes while the World Cup delay would be "disappointing" there could be an upside for Wales, who have a new coaching regime under new boss Warren Abrahams.
"If you do want to look at the positive looking at the Welsh side, they do have new coaches and that maybe gives them more time to settle in and get their plays and maybe have some warm-up games in between."
After World Rugby announced its recommendation, Charlotte Wathan, the Welsh Rugby Union's general manager, women's rugby said: "We're obviously very disappointed for the players and staff who have supported the development of the programme towards RWC 2021.
"Ultimately, player welfare and public health must come first at this time."