By Kat Wong in Canberra

When Kate Marshall was about to start IVF, she worried her chances of promotion could dwindle.

And she isn’t alone.

Every year, tens of thousands of Australians take time off to undergo assisted reproductive technology treatment or receive other reproductive health treatments.

Disability service provider Scope will be one of the first employers in Australia to provide 12 days of leave for severe menstrual pain, endometriosis, IVF, vasectomies, menopause, gender transitioning therapies and other health issues.

And now, the Health Services Union is calling on the government to extend reproductive leave to all Australian workers.

“I did want to work but I also desperately wanted to have a family – why should a person have to pick one or the other?” Ms Marshall, who is also the union’s national senior assistant secretary, said.

“It shouldn’t be down to being lucky enough to have an understanding boss.

“All workers deserve this critical leave.”

Employees, especially women, were burning through their leave to look after their reproductive health, Ms Marshall said.

This extra 12 days of leave could allow women to stay in the workforce for longer, accrue more superannuation and help close the gender pay gap.

It would also prevent women from having to make up excuses about their days off, potentially lowering absenteeism.

“The most important thing is to break down that taboo,” Ms Marshall told AAP.

“If you actually have a conversation with your employer and they understand what an employee going through, they’re going to hopefully be far more understanding and lenient, rather than expecting them to fit into a system that doesn’t fit.”

Contraception, hormone therapy, hysterectomy, menstruation, miscarriage, pregnancy, poly-cystic ovarian syndrome, screenings for breast and prostate cancer would also be covered under reproductive leave.

Vanessa Ferguson, chief executive at reproductive services provider Adora Fertility, has backed the union’s announcement and said it would help improve accessibility to treatments.

“This is another step in the right direction in supporting and acknowledging the unspoken cost of fertility treatment,” she told AAP.

An increasing number of LGBTQI people have sought access to reproductive health services, according to Monash IVF chief operating Officer Hamish Hamilton.

While he supported the proposal, any leave entitlements must be inclusive and attempt to remove discrimination and unfair burdens that some patients face, he said.