Women migrants who travel to Britain and other developed countries are put at risk of exploitation and abuse because governments "overlook and ignore" them, the United Nations says, and there is a "dire need" for stronger co-operation between rich and poor countries to ensure migration around the world is better managed.
The UN Population Fund (UNFPA) revealed in a report that women now make up half of the world's 191 million international migrants, compared with less than 45 per cent in 1960.
They contribute billions to the economies of the countries they travel to in terms of taxes and consumption, and are also more likely than male migrants to send remittances to help their families in their countries of origin.
But the report warned that governments in the West were not doing enough to protect women from forced migration in the forms of sex trafficking, enforced marriages and employment abuses. It also attacked countries such as the UK for stripping Aids-ravaged countries such as South Africa of key female workers such as nurses to plug their own staffing gaps.
When female migrants arrive in Western countries, they often miss out on health care because they are not aware of their rights and remain at risk of exploitation from employers.
Thoraya Ahmed Obaid, executive director of the UNFPA, said: "There is a dire need for greater action to address the lack of opportunities and human rights violations that lead many women to migrate in the first place.
"There is an urgent need for stronger co-operation between countries to make migration more safe and fair. We call on governments to recognise and value the contributions of migrant women and to promote and respect their human rights."
She pointed to a new law in Sweden that prosecuted men who were caught with sex workers rather than the women as an example of how the problems of sex trafficking could be tackled.
Ms Obaid said that women often suffered double discrimination from being both female and migrants. She added that rather than the imposition of quotas, such as those being discussed for new EU entrants such as Bulgaria, Britain should work with poorer countries to build up their own education and health systems so that people were not forced to travel abroad to escape grinding poverty.
But she also upheld the rights of people to travel abroad in search of a better life. "Migration for economic well-being is a human right," she said. "These people contribute a lot to economies... Countries should discuss together how to manage migration. If it is done well, then it is a win-win situation for both the sending and the receiving countries."
Her view contrasted sharply with that expressed by the new director general of the Confederation of British Industry, Richard Lambert, who warned earlier this week that the wave of cheap labour from eastern Europe could put social cohesion at risk.
The UN report also revealed that claims about "floods" of migrants were exaggerated. Since 1960, the proportion of migrants has remained stable, accounting for 2.9 per cent of the global population. The US takes the highest proportion of the world's international migrants, 20 per cent, compared with just 2 per cent in the UK. Refugees and asylum-seekers represent just 3 per cent of all international migrants in Europe.Reuse content