People move from one place to another for many reasons. Some migrate to join family members. Others, such as airline personnel, truckers, people serving in uniformed services, petty traders, and sex workers, travel for professional reasons. Many people move in search of economic opportunities. Yet others are pushed by war, human rights abuses, ethnic tensions, violence, famine and persecution.

Movement may be voluntary or forced. It may be temporary, seasonal (e.g., during harvests), permanent or circular (returning home repeatedly). Categories shift: people intending to migrate permanently may change their minds and return home; people intending to stay only a short time may settle permanently; students or tourists entering countries legally may become undocumented migrants when their visas expire; undocumented migrants may have their status regularised; and refugees and internally-displaced persons may be able to return to the communities from which they fled, as they are currently doing in Angola and Afghanistan for example.

Though the reasons for people's mobility differ, the risks and vulnerabilities that they encounter to their sexual health are similar, as are the approaches to deal with them.

Individual risk and social vulnerability

Risk factors to sexual health are both individual and social. Like other people, migrant and mobile people have a responsibility to take care of their own health. However, their behaviour is often different when they are away from home and the social norms that guide and control behaviour in stable communities. Some people may indeed choose to leave home specifically so that they can more comfortably practise a stigmatised profession (e.g., sex work). When they travel without partners, and because of loneliness or as a result of social pressure, some migrants and travellers may engage in behaviours that put them at risk of undesired pregnancies or STIs. People who move from a conservative society to one perceived to be more liberal may be ill-equipped to deal with sexual freedom: they may not understand the norms or limits in the new society, and how to protect themselves in that context. Such cultural misunderstandings cause difficulties for women but also for men; more than one immigrant or male traveller who has misperceived sexual codes and ground rules has ended up being accused of rape.

For most migrants, daily life is dominated by priorities other than sexual health. Refugees worry about missing family members or mourn their dead. Newly-arrived immigrants are concerned about food, housing and finding a way to earn a living. Mobile workers, such as miners and truckers, may see far more imminent danger in their work environments than in the hypothetical risks of HIV/STIs. People travelling, fleeing danger, or pursuing a dream through migration are understandably reluctant to deal with the possibility of an illness that would slow them down. They may delay thinking about a health symptom until it becomes a problem that is impossible to ignore. An immigrant girl may come for a first antenatal consultation only when she is at an advanced stage of pregnancy; a trucker may present at a clinic only when an STI is very painful, and a would-be migrant in transit may find out about his HIV-positive status only when he has advanced AIDS.

Ill-adapted migration policies

Thus risk factors such as social pressure, cultural naiveté and more immediate priorities increase migrants' vulnerability to sexual and reproductive ill health. Other social factors operate less directly, by putting people in situations where risk behaviours are more likely to take place. Poverty, powerlessness, lack of respect for human rights, distrust of foreigners and marginalization drive discrimination and exploitation, creating risk situations in which people have very little individual choice at all.

Ill-adapted migration policies are behind many of the social factors that increase the vulnerabilities and sexual and reproductive health risks of migrants. Such policies may, in fact, seriously undermine public health policies. For example, policies encouraging labour migration of single people force them to migrate without their partners; this may increase their recourse to casual sex and thus the risk of HIV/STI infection. These policies affect not only the sexual health of the mobile people but also that of their partners and spouses, children, other family members left behind, and even entire communities.

The special vulnerability of women and children

The last 10 years have seen an increased feminisation of migration; women currently represent about 50% of the 175 million worldwide migrants estimated by the International Organization for Migration. Individual and social factors create special risk factors for women. For example, women travelling alone may have little choice but to sell sex for survival, or to establish partnerships in transit or at their destinations in order to gain access to protection. Refugee and internally-displaced women without male partners may similarly find themselves unprotected. In addition, they may have been exposed to rape as a weapon of war, or to rape in camps, where sexual violence is one outcome of male boredom, depression and substance abuse. The risk of sexual violence also increases in gender-segregated and unregulated sectors of the economy, for example, for female traders, domestic workers and sex workers.

The trafficking of human beings has been a lucrative trade for centuries, but recent opportunities created by globalisation – combined with tightening restrictions on immigration and labour migration – have contributed to an increase in the numbers of persons smuggled and trafficked. Women and female children and adolescents are particularly vulnerable to trafficking for sexual exploitation. UNICEF estimates that about 1 million children are forced into the sex trade every year worldwide. In countries of the European Union, there are numerous indications that unaccompanied (or separated) children and adolescents from Eastern Europe and the Balkans are being trafficked. Persons trafficked for sexual exploitation face significant risks to their mental and reproductive health, such as sexual violence, unwanted and unsafe pregnancy and motherhood, unsafe abortion, and HIV/STIs. Sexual exploitation of children often means that children will give birth to children if contraception – including emergency contraception – and safe legal abortion are unavailable.

Approaches used

It has often been pointed out that it is not migration or mobility itself, but rather the situations encountered and the behaviours expressed that increase vulnerability and risks for mobile and migrant populations. The patterns of mobility discussed in the first section of this article define the conditions of the journey and its potential subsequent impact on health (regular or irregular, forced or voluntary migration). Migration status usually defines access to health and social services. Efforts therefore can and should be made to improve the access of mobile and immigrant populations to health promotion, care and support.

Measures needed to reduce risks for mobile populations are the same as for any other group. They include provision of health education and information, voluntary counselling and testing, family planning and antenatal care, and STI treatment. Peer education is a particularly important approach for such populations, as is active outreach that will ensure that information and services offered are not only language- and culture-appropriate but also "user friendly" (understandable, accessible, welcoming, easy to use).

Measures to reduce vulnerability are even more important. These are attempts to go beyond addressing individual behaviour change to address the social factors sketched out above. Some measures to decrease sexual violence, for example building latrines where women can get to them safely, are relatively simple. Other approaches may require more fundamental reorganization. These include measures to reduce the frustration that leads to violence, or the factors that drive discrimination, lack of respect of rights and exploitation. They also include efforts to change migration policies that directly or indirectly promote behaviour that has a negative impact on sexual health.

Two fundamental programming bases are important for reducing migrants' risks and vulnerability: 1) use of a rights-based approach – based on the principle that migrants have a right to health, thus to information and services – and 2) involvement of migrant communities. Leaders and representatives of migrant and mobile groups know their needs and how to meet them. At the same time, governments are responsible for including health and immigration authorities in the definition of priorities and development of policies of inclusion rather than exclusion. Rights and responsibilities for both migrant and host communities must be balanced. Governments may have difficulties, however, in programming for target groups such as irregular migrants. It is here that international organizations and NGOs can play crucial and complementary roles of advocate, spokesperson, and link between stakeholders. Such supra-national agencies can also facilitate essential cross-border and cross-continental initiatives that link countries of origin, transit, destination and return.

What is needed

Much remains to be done in this field. The evidence base concerning migrant health in general, and migrant sexual health specifically, needs to be improved. Programmes are far too often put into place in the absence of baseline assessments, and priorities are far too often donor- rather than needs-defined. Programmes are far too often unevaluated, and knowledge about lessons learned remains unshared.

Addressing the pattern and status factors that may enhance vulnerability for migrant and mobile populations poses challenges for migration health management and for policy formulation. It also poses complex medical, legal and ethical questions. Should diseases posing a public health risk not be treated as migrants travel? Should treatment available to national citizens be offered to people who may not stay in a country? Should a migrant with a health condition that will be expensive to treat be excluded from a health programme or be rendered inadmissible to a country? How can we provide services for one community without providing services for another?

In sum, addressing the sexual and reproductive health needs of mobile and migrant populations poses complex challenges and fundamental questions about balancing individual rights and responsibilities, and the rights and responsibilities of nations.