They call it "Bombay Colony". The village of Basatpur, in Bangladesh's south-western Jessore district, would seem a world away from the glitzy bars of Mumbai, India's showbiz capital. There are no Bollywood stars in Basatpur, just grinding poverty and choking dust.

But the arid, rundown border village has earned its reputation. For two decades, the women of Basatpur have trekked across the border and made their way to Mumbai where they have made a living as dancing girls at the city's notorious "ladies bars".

Anjuman Ara Begum, 45, has been there and back. "The girls go because there's nothing to eat here," she says. "The men can't earn a living, so they send us across the border." "All this," she adds, waving a hand at her tin-roofed brick house, "all this I made with money I earned in Bombay. I put two sons through college and married off my daughter."

Walking along the single road that strings Basatpur together, it's easy to see which families have sent members to Mumbai and which ones haven't. The thatched huts contrast sharply with the brick buildings, mirroring the diverging paths chosen by their occupants.

In a Muslim-majority country where the idea of women migrating for economic reasons without male guardians is still cause for unease and shame, Begum is a rebel. Remittances from migrant workers stood at $12.8bn (£7.8bn) in the fiscal year ending 30 June 2012, about 11% of Bangladesh's GDP. But the official number of female migrants was just 30,000 in 2011 – less than 5% of the total outflow, according to data supplied by the government's Bureau of Manpower Employment and Training (BMet). "Social attitudes towards women going abroad to work are still conservative," says Dr Nurul Islam, director of BMet.

For decades, Bangladesh banned unskilled women from seeking work overseas. Even though the ban was officially lifted in 2005, migrating abroad for work remains quite difficult for women in practice. Bureaucratic obstacles, high costs and negative social attitudes mean relatively few women migrate along official channels.

According to a study funded by the UN Development Programme, only 40% of Bangladeshi women migrants use recruitment agencies. The rest are believed to make private arrangements with the help of relatives and friends.

"Discouraging women from migration pushes migration underground, placing women at even greater risk of exploitation," says Selim Reza, a researcher with the Refugee and Migratory Movements Research Unit, an affiliate of the University of Dhaka. "In many villages along the Indian border, especially in Jessore and Satkhira districts, women have traditionally walked across without papers, even though the government chooses to ignore this."

In dirt-poor Basatpur, migrating anywhere that required a passport, visa or aeroplane ticket was out of the question. Pushed by poverty and pulled by the lure of well-paid jobs in distant Indian cities, the young women defied tradition to make the perilous journey across India in search of freedom and cash.

"Although the government and NGOs say this is trafficking, the women go of their own accord, usually helped by their husbands," says Arif Hossain, a local journalist who has studied the "bar girls" phenomenon. "In some villages, two-thirds of households have sent someone to Mumbai at some point."

Begum made the 2,000km journey to Mumbai in 1995. With two other women, she walked across the border and took a bus to Howrah station in Kolkata. From there, they took a train to Mumbai. Begum says she waited tables at a Mumbai bar, but acknowledged that the real money was in the "dancing". Some of the dancers sell sex discreetly to customers. "Dancing girls consider themselves a cut above prostitutes," says Hossain. "There is always the benefit of the doubt."

But the road to Mumbai is a rocky one. For some village elders and religious leaders, bar jobs remain a mortal sin. "It's a deal with the devil," says a local imam, who asked not to be named. "Unless these women do tauba [repent], they are in trouble."

Begum says there have been attempts to stop the migration to Mumbai through village arbitrations, but she remains defiant. "When I was starving no one fed me," she says. "I did what I had to do to keep body and soul together."

Mumbai banned dance bars in 2005, blaming them for a climate of moral decay – but an illegal trade still exists, say observers. "Since the authorities cracked down on dance bars, many of the 75,000 or so girls ended up on the streets," says Shailendra Yashwant, a Mumbai-based journalist. "Many were loaded on to trucks and trains, and shipped out of the state. These women are terribly vulnerable."

Nurul Islam of BMet denies there are women crossing or migrating into India without passports or visas. "These are all cases of trafficking," he says. "When there is a porous border, traffickers will always dupe innocent women."

Many experts say the government and some NGOs are sweeping the social and economic issues under the carpet by focusing on trafficking. Some organisations are fighting back. The Management and Resources Development Initiative, a Dhaka-based NGO, has started a skill-development institute in Basatpur where young women are taught handicrafts.

Begum's neighbour, Shamima Sultana, 33, who returned from Mumbai five years ago, is among the first batch of graduates. Sultana says she would never have crossed the border if she had found work locally. "I was helpless," she says. "No girl would like to do what we did."