Last year Indonesian Anniesa Hasibuan made history as the first ever designer to feature hijabs in every outfit on a New York Fashion Week catwalk.

"Even some people who are not Muslim, are interested in wearing Muslim fashion," she told Fairfax Media.

Just 30 years ago it was relatively rare to see an Indonesian woman wearing a hijab or veil, says Dr Ariane Utomo, a social demographer at the Australian National University, in the 2015 paper Who wears a hijab?

Dr Utomo said the hijab wasn't very popular when she was growing up.

However today it has become relatively common, particularly among middle-class Muslim women living in urban areas.

"I was in a public junior high school from 1990-1992 and in that time, there was only one girl in my entire year, probably out of 500 students, who wore a hijab," she said.

Dr Utomo believes the hijab's rise in popularity is part of Islam's growing influence.

"I think it's got a lot to do with the revival of Islam in Indonesia," she said. "I think there is an increase in the consumption of religion in society."

Muslim consumers spent around $US266 billion ($347 billion) on clothing worldwide in 2013, a figure that is estimated to almost double by 2019, according to a report by Thomson Reuters and Muslim research firm DinarStandard.

This growth overlaps with the boom in the Muslim population which is estimated to increase from 1.6 billion in 2010 to nearly 3 billion by 2050, based on statistics by Pew Research Centre.

Fashion household names, such as Dolce and Gabbana, have already taken advantage of the modest clothing market, releasing a line of hijabs and abayas last year.

Bonar Tigor Naipospos, vice chairman of the Setara Institute, which advocates for political freedom and human rights, said there is social pressure for women to "look Muslim" in Indonesia.

"Some women are pressured to put on [the] hijab otherwise they will be bullied by their families, friends and social environment," he said. "So they wear [the] hijab in order to be 'in the group' rather than 'outside the group'."

For 44-year-old Indonesian Lenita Sulthani, her choice not to cover her head, even after a pilgrimage to Mecca, has exposed her to questioning from family and strangers.

In her workplace all the women wear hijabs and Ms Sulthani said she constantly gets asked why she doesn't wear one.

"My mother keeps asking me why, she is old and I don't want to hurt her," she said. "[But] this is about my choice, I don't want to cover my head just because I was forced to do so."

However Shelvy Afrin, vice president of Muslim fashion brand Shafira, a sponsor of Indonesia Fashion Week, said there is no pressure for women in Indonesia to wear the hijab and more women are doing so because designs are now more fashionable.

"It was not a really common thing to wear a hijab [in the past], now more and more people are wearing a hijab and it has become a trend," she said. "They can be fashionable but at the same time they can fulfil the requirements of their religion."

Ms Afrin said the rise in popularity for modest wear is part of the brand's success and there is great potential for it in the global market.

Australian designer Jaimie Sortino, whose whimsical gowns inspired by the sky blue hydrangeas close to his Adelaide home featured in the opening ceremony of Indonesia Fashion Week, said he had noticed a global revival of modest clothing.

"I have noticed that there is that kind of revival in modest clothing," he said.