An Australian sanitary towel firm is facing a backlash over an advert which shows a woman on her period transforming into an unstable and larger version of herself, which viewers have complained is fat-shaming.

The SOFY BeFresh advert, called "Ugh Moments", shows a woman heading for her front door, where she meets a fuller-figured version of herself dressed in identical clothing. She sighs when she checks her phone calendar and realises she’s starting her period.

Showing the scenario that would unfold if the woman didn’t use the product the advert is pedalling, the woman gorges on ice cream and pizza, binge-watches TV and is generally irritated by everything around her.

“Goodbye ugh” is then emblazoned across the screen, and is followed by an alternate ending in which the woman leaves her irrational and emotional alter-ego behind to get on with her day after using the product.

While some enjoyed the video for satirising the discomfort women feel during their periods, others were disappointed that a larger woman was used for comedic affect and accused the commercial played on "hackneyed" stereotypes.

The larger actress who appeared in the video responded to the criticism by saying “I reckon I’m a massive babe”.

But many argued that it was insulting to recruit a larger actor to demonstrate a visual metaphor of when a woman is a worse version of herself.

The Independent has contacted Unicharm Australia, who manufactures the product, for a comment on the situation.

In a response to a complaint from a viewer, the firm wrote: "The SOFY BeFresh television commercial was extensively researched with Australian females before launching and we certainly do review all feedback from the research to ensure that the key message and terminology are appropriate for the market."

The video comes after YouTube star Nicole Arbour was criticised for a video in which she claimed that fat-shaming is “made up” and that she is attempting to help obese people lose weight.

"If we offend you so much that you lose weight I’m ok with that. Yep, I’ll sleep at night," she said.

So-called plus sized models including Tess Holliday hit back at Ms Arbour, and tweeted: "Fat shaming doesn’t save lives, it kills them."