Lori Camarata says the last place she would expect to be sexually assaulted was on her daily commute between home and work.

But early this year, Ms Camarata experienced something that has made her wary of catching public transport ever again.

"He just came over to me and pinned me up against the door and he continued to press himself against me," she said.

"That's when I felt him touch my ass and then I felt him touch me again."

Ms Camarata had been sexually assaulted by a fellow passenger on a busy tram from St Kilda Road in Melbourne's CBD to Thornbury in the city's north.

The experience left her angry and shaken.

"I was pretty scared and frozen. You are told not to make a big deal about things, and I didn't react the way I thought I would," she said.

"It's probably the last place I'd expect that to happen, and I wouldn't expect it in that space. It's been difficult catching the tram since then. It's always packed and I just feel distressed in that situation."

She is one of two women that have spoken to the ABC sharing similar stories of being touched inappropriately and sexually assaulted on busy trams.

"I think it happens all the time and I wouldn't be surprised if more of it happens," Ms Camarata said.

Ms Camarata was pinned up against a tram door on her trip between home and work. ( ABC News: Tom Gelai )

'You could tell it was sexual'

Recent crime figures released by the Victorian Crime Statistics Agency how reports of sexual assault have significantly increased.

In four years, sexual assault has almost doubled, with steady increases in reported cases in each of those years.

Deputy Police Commissioner Wendy Steendam said while reports of public transport sexual assault were infrequent, the upward swing in overall reportage was disturbing.

"We certainly have seen an increase in sexual assault reportage but it's quite infrequent on public transport," she said.

"That's not necessarily what's driving the figures, but certainly those instances where we're seeing public instances of sexual assault is concerning and we're supporting women through the reporting of that," Deputy Commissioner Steendam said.

India Rose had similar experiences to Ms Camarata.

She was catching a tram home from university when a man felt her bottom and leg.

"You could just tell it was sexual. At first I thought it was nothing because I'm a positive-minded person, but you just know," Ms Rose said.

"I was just so angry and felt so violated and I don't drive so I need to catch the tram. I shouldn't be made to feel so unsafe in a public space."

Ms Rose reported the man to the police and the incident is under investigation.

Being 'touched up on a tram' now being talked about

Carolyn Worth, spokesperson for the Centre Against Sexual Assault, said reported cases like those of Ms Rose and Ms Camarata had greatly contributed to the significant increase in reported cases of sexual assault.

"I think being touched up in a tram or a nightclub is quite unacceptable and I think if you even go back a few years people just accepted it as how things were," she said.

"Slowly over the last few decades people have been comfortable talking about it.

"Now we get calls where people say I wasn't abused by an institution or any of the churches, but I just think it's time I talked about this."

Ms Worth said she expected the number of reported cases to go up, especially as the awareness and understanding of how to report the issue increased.

"Many women don't know that you can make an anonymous police report through Victoria Police," she said.

"So as more women become aware of this I hope there is an increase in reported cases."