Prostitution is the practice of engaging in sexual activities with an individual other than a spouse or friend in exchange for payment. Although prostitution is a global and deeply rooted social phenomenon, substantial disparity exists in its perception, depending on different social and cultural factors.1 One view is to consider prostitution as a crime that induces violence; such as human trafficking, sexual abuse, rape, physical or verbal abuse, and racial discrimination, including serious violations of human rights.2,3 The other extreme is to consider prostitution as a type of occupation in which the people involved are known as special workers, or "sex workers".4 Despite the different points of view, a general consensus shows that women engaging in prostitution may be exposed to serious health risks,5-7 such as sexually transmitted diseases and HIV.8-10 In addition, studies on mental health problems suggest that depressive symptoms, anxiety, and psychological distress are higher in women in prostitution.5,11,12

To examine the mental health of women who are engaged in prostitution, the characteristics of the process of prostitution must be understood. According to previous studies, prostitution is essentially a multi-traumatic phenomenon.13 First, women in prostitution may occasionally be involved in violence.3 A recent study of 854 women in prostitution in 9 countries reported that 70 - 95% of the women experience physical assault, among which 60 - 75% had been raped.2 Similarly in Korea, where prostitution is illegal, prostitutes experience sexual and physical violence. In a study of 100 Korean women in prostitution, 96% of respondents answered that they experienced physical danger from weapons, physical violence, and injury from rape.14

Direct or indirect exposure to traumatic events in the course of prostitution is associated with psychological problems, including PTSD.15 PTSD can result from extremely traumatic experiences that are direct, personal, and involve actual or threatened death or serious injury; threat to one's personal integrity, witnessing an event that involves death, injury, or threat to the physical integrity of another person, or learning about unexpected or violent death, serious harm, or threat of death or injury experienced by a family member or close associate.16 Several factors have been associated with an increased risk of developing PTSD following trauma exposure. These include background variables such as childhood trauma, comorbid mental health problems, family instability, and substance abuse.17,18

PTSD is a chronically disabling disorder associated with a large degree of morbidity. It rarely exists as a pure disorder and psychiatric comorbidities such as depression, alcohol abuse, substance abuse, other anxiety disorders, and suicidal tendencies worsen the burden of this disorder.19 PTSD may be especially severe or long lasting when the stressor is planned and implemented by humans such as war, rape, incest, battery, or prostitution rather than natural catastrophes.3

Previous studies on prostitution have shown that prostitutes have a high prevalence of PTSD. Sixty-eight percent of 827 prostitutes in 9 countries met the criteria for lifetime diagnosis of PTSD.3 The severity of PTSD symptoms in the participants in the above study was in the same range as treatment-seeking combat veterans,20,21 battered women in protective shelters,22,23 rape survivors,24 and refugees.25 A study performed in Korea found that 81% of women with a history of prostitution had symptoms of PTSD,14 and research has suggested that prostitutes might have many risk factors for developing PTSD. Experiences of child sexual abuse are commonly reported among prostitutes. Additionally, violence related to prostitution and adult sexual assaults are prevalent.5,26

Exposure to violence through engagement in prostitution may contribute to persistent and severe psychological problems in not only direct victims but also people in close proximity who can suffer from a range of emotional symptoms in spite of not being directly exposed to the traumatic events. This phenomenon has been described by a number of terms, including indirect traumatization, and has been documented among children of Holocaust survivors,27 wives of combat soldiers,28 and therapists who treat trauma victims.29 A number of terms describe the negative impacts that result from working with traumatized victims, including "burnout", "compassion fatigue", "secondary traumatic stress", and more recently "vicarious traumatization".30

The term "vicarious trauma" was first used by McCann and Pearlman to describe pervasive changes occurring within clinicians or counselors over time from working with victims who experienced sexual trauma.31 In our study, the term was used to describe secondary trauma and/or traumatic stress. The unique features of counseling for sexual violence that contribute to the development of vicarious traumatization result from empathically listening to victims as they share graphic details of their traumatic experiences and psychological pain. Compared to other fields, sexual violence counselors have a higher risk of experiencing vicarious trauma.31,32 In a qualitative study of female counselors working with sexual assault victims, approximately 2/3 of participants reported intrusive imagery, dreams, and thoughts, including increased vigilance related to their safety, which decreases the level of trust in social interactions.33 Counselors and researchers who experience these negative effects may stop working with traumatized individuals,34 and the activists helping women exposed to trauma may experience more vicarious traumatic effects than workers in other fields. Therefore, recognizing and resolving vicarious traumatization may be crucial to the well-being of victims as well as counselors.35

Only a few studies examined PTSD symptoms or its associations in the mental health of prostitutes and control groups. In particular, a controlled comparison of vicarious traumatic effects among field workers who help female prostitutes has not yet been performed.

The present study compared the mental health status of former female prostitutes who live in shelters, field workers helping prostitutes in shelters, and a normal control group. In keeping with the literature, we examined the specific PTSD symptoms and other manifestations of distress and mental health among the 3 groups.

We investigated PTSD symptoms of ex-prostitutes, activists helping prostitutes, and control subjects in the community. We also examined the association between PTSD symptoms and other mental health problems, such as stress reactions, sleep, smoking and alcohol problems. There are 3 implications in this research. This is the first study dealing with PTSD symptoms of not only the women engaged in prostitution, but also the vicarious traumatic effects and mental health of field workers helping the prostitutes. Second, contrary to previous studies conducted on prostitutes, this study focused on ex-prostitutes who had escaped prostitution and were rehabilitating in shelters. Third, while previous studies on female prostitutes were single-group studies, this study was a controlled and compared study among 3 female groups.

We found that field workers helping prostitutes experienced PTSD symptoms more frequently and more severely than control group. These workers also reported higher rates of tension, sleep troubles, and smoking problems than the control group. These findings support our hypothesis that traumatic experience related to prostitution would have influence on mental health, such as PTSD, not only among the ex-prostitutes but also among the activists traumatized indirectly.

To out best knowledge, there has been no previous controlled study that examined the level of vicarious trauma among field workers helping prostitutes. The present findings are consistent with previous non-controlled studies on vicarious trauma. Vicarious traumatization in sex violence counselors showed a pattern similar to that of previous studies despite its insignificant influence. Specifically, the influences include intrusion of traumatic images,32,33,41,42 avoidance,41 depression and frustration with an increase of drug use,42 disordered sleep, reduction of energy,33,43 damage to self-confidence and values32 with a change in cognitive schema.43 According to previous findings, variables that moderate the development of vicarious trauma include personal characteristics, such as gender,41 age44 and counselors' own trauma or abuse history.45,46 However, in regard to counselors' own trauma, Schauben and Franzier29 did not find that past trauma history significantly interacted with caseload characteristics in producing symptoms in counselors. It was also reported that there was no notable difference in vicarious trauma symptoms between those with and without personal abuse history.47 We found that vicarious trauma symptoms correlated significantly with the amount of exposure to trauma and the work characteristics such as the percentage of sexual violence cases within the caseload29 and the number of working hours spent with traumatized victims.41,48-50 Therefore, generalization of the results is difficult, and it may be necessary to consider individual characteristics of counselors whereas other variables that may be associated with the development of vicarious trauma are negative coping strategies, level of personal stress, and training for new and experienced counselors.51

Although Roman et al.4 reported that there was no difference in mental health between sexworkers and control groups, numerous studies have suggested that sex-workers experience diverse psychological symptoms; such as anxiety, depression, and personality disorders.5,11,12 Similar results also found that women who engage in prostitution experience PTSD symptoms as a psychological consequence of violence associated with prostitution.10,13,52,53 Compared to other groups, prostitute victims in the present study reported severe and frequent rates of PTSD and other distress symptoms, such as tension, aggression, somatization, anger, depression, fatigue, and frustration. Although ex-prostitutes who participated in this study had not engaged in prostitution for an average of 8.7 mos, they still experienced serious PTSD and other distress symptoms. The results were consistent with a Canadian study that compared women who were still in prostitution to those who were not. The study suggests that ex-prostitute respondents are only slightly less likely to experience depression but are more likely to experience anxiety attacks and emotional trauma than their counterparts who continually engage in prostitution.54

Recently, an Australian study showed that female street-based sex workers who reported current PTSD symptoms had experienced a significantly larger number of trauma than sex workers who did not report current PTSD symptoms.55 In addition, the current study found that the reported PTSD symptoms increased proportionally to the length of the years that women engaged in prostitution. Multiple traumas related to engagement in prostitution for a long time are associated with the risk of developing PTSD and severity of symptoms. These results were consistent with previous research showing that the longer the exposure period to trauma, the more severe and persistent the PTSD symptoms.15,56 Therefore, we believe that ex-prostitutes who engaged in prostitution for a long time are in need of great help and support.

In our study, smoking and drinking problems among women who engaged in prostitution were serious compared to the control group and the measures were positively correlated to the severity and frequency of PTSD symptoms. Previous studies showed that the risk of developing drinking problems is higher among women with PTSD caused by sexual violence,57 while drug abuse problems are higher among prostitutes.11,58 The theory that alcohol and cigarettes play a role in self-medication to reduce psychological pain is widely known,59 and 1 study reported that women use drugs to obtain a numbing effect during prostitution. Substance abuse enables PTSD patients to attain cognitive avoidance, while treating the concomitant substance abuse is difficult in cases with residual PTSD symptoms, due to their continuous avoidance.54,60 Therefore, problems pertinent to substance abuse should be handled at the same time as the PTSD of female prostitutes.

There are several limitations to the present study. First, demographic data such as age, marital status, education, and social and economic status showed significant differences between exprostitutes, field workers, and controls. Younger age, lower socioeconomic status, and lack of education are associated with the development of PTSD, but neither increase the risk by more than 50%.61,62 Therefore, the findings might have been influenced by demographic factors. Second, the questionnaires were all self-reports with no psychiatric diagnosis by an outside expert. Third, field workers' vicarious trauma symptoms were assessed using a modified version of a questionnaire that was developed to assess the direct victims of PTSD. Fourth, past trauma history such as child sexual abuse, rape, and family instability, which are considered risks of developing PTSD, were unfortunately not examined in this study. Since variables related to vicarious trauma were not examined in the field worker group, it is difficult to determine whether the trauma symptoms of field workers were caused indirectly by working with ex-prostitutes or directly by the field workers' own risk factors for PTSD.

Notwithstanding these limitations, this study contributes to our knowledge of the populations that are directly and indirectly traumatized by after escaping from prostitution, women show diverse psychological symptoms related to PTSD and distress; furthermore, the field workers helping prostitutes also report considerable vicarious traumatic symptoms. These findings show that engagement in prostitution may increase the risks of exposure to violence that may act as psychological trauma not only to the victims themselves but also to the people who help them, indicating that the influence of the trauma lasts for a long time. PTSD is a chronic condition that can be a social and economic burden to the victims, people around them, and society. Therefore, early diagnosis and treatment are extremely important.63

These findings raise several issues. In Korea, the act on the prevention of the sex trade and protection of its victims in 2004 criminalized human trafficking and stiffened penalties for brothel owners. A number of shelters, self-support centers, and legal, medical, and vocational assistance including secure housing and paying off debts have been provided. However, mental health support is relatively insufficient. The results of the present study suggest that psychiatric intervention for women engaged in prostitution are required and outreach services such as counseling centers and crisis hotlines are necessary to prevent mental health problems. Future research is needed to develop an assessment method for vicarious trauma of prostitution and specific factors that may contribute to vicarious trauma or protect field workers from vicarious trauma need to be evaluated. In this regard, longitudinal studies may be useful in understanding the processes involved in vicarious trauma and the temporal relationship between coping strategies and the traumatic effects of contact with victims.