Evita Nicole Sarmonikas' family have posted a message on Facebook saying she died on March 20 after suffering a heart attack following surgery.

They say the only response they had received from the hospital in Mexicali, Mexico is to cling to their waiver, denying any liability for the 29-year-old's death.

"There have been no answers and their only offer of 'co-operation' was an urgency to return her to us in the form of ashes. The Australian Embassy has strongly advised we do not allow this to happen," the family's Facebook post says.

Ms Sarmonikas' family hinted that she had travelled to Mexicali, the capital of the Mexican state of Baja California, with her boyfriend to have a cosmetic procedure.

Without saying what type of procedure, the family wrote that Ms Sarmonikas, who grew up on the Gold Coast, was "filled with certain inadequacies".

"Her perfect and whole soul was not strong enough in light of a world that constantly bombarded her with an urgency to demand more from her self and her body," the family wrote on Facebook.

"This was not the way to go home, no woman should risk death to improve on perfection.

"Tomorrow morning when you look in the mirror say to your self 'I am enough, I am worthy, I am perfect just the way I am'.

"Don't listen to a world that is hungry to fill your insecurities with poison. Stop feeding an industry that hates humans, especially women in the natural state and their perfect birth bodies."

The family said they had learned an autopsy had been conducted by a medical team at the hospital in Mexicali where she died.

"Evita was a beautiful, young, healthy woman and the surgery was a simple procedure with minimal risks," the Facebook post said.

"Australian medical advice has been that even in the case of cardiac arrest a healthy young body can often be brought back to life when surrounded by a fully equipped hospital and a competent medical team.

"The Australian Embassy has been clear on not allowing her body to leave Mexicali, or allowing her little body to be cremated before an independent autopsy and external opinion is sought."

The Department of Foreign Affairs and Trade said it is providing consular assistance to the family of an Australian woman who died in Mexicali, Mexico.

"We will not be providing further details owing to privacy considerations," a department spokeswoman said.

The family said it has been advised to travel to Mexico and say they face costs of up to $20,000 to return the woman's body to Australia because she had not taken out any travel insurance. They said they want to ensure Ms Sarmonikas was "treated ethically" and bring her back home.

They said the Mexican doctors had promised her "more perfection to fill an emptiness that began developing early in her childhood".

"This emptiness further expanded with traumatic experiences in her adult life and the constant social boarding of a false beauty illusion," a Facebook post said.

The family said the Australian government could not provide financial, legal, or medical assistance.

"Nor have we been able to find or access agencies or organisations equipped to assist in situations of this gravity," the family said.

Ms Sarmonikas is a former Gold Coast Hope College student and is also believed to have attended Coombabah High School on the Gold Coast.

One of her former teachers wrote on Facebook that Ms Sarmonikas was "one of the most beautiful, kind and intuitively intelligent girls I have ever known".

A friend wrote that Ms Sarmonikas "inspired many with kindness, generosity, beauty and love."

"Thank you that you put her in my life," the friend wrote.

"I thank you I was able to see her and speak to her. I thank you that she was happy before she passed. I thank you for knowing me inside out and knowing that she'd be the perfect best friend and sister a girl could have."

Another friend, Helen, wrote: "Eva was a shining light in this dark and unforgiving world. Beautiful inside and out, gracious, sensitive, caring and giving, who lived by her motto of laugh, live, love. Eva you will be so sadly missed."