The incidence of premarital sexual activity among youth has been dramatically increased due to the widening gap between age at menarche and age at marriage (Gibbs et al., 2014; Motamedi et al., 2016; Shu et al., 2016; Yip et al., 2013). As most acts of premarital sex are unprotected, sexually active youth are at high risk of exposing to the human  immunodeficiency  virus/acquired immunodeficiency syndrome, sexually transmitted diseases (STDs), unintended pregnancy and resultant unsafe abortion (Azmawati et al., 2017; Shu et al., 2016; Xu et al., 2019; Yip et al., 2013). In many countries, approximately up to 51% of adolescents engage in premarital sex (Akibu et al., 2017; Azmawati et al., 2017; Regassa  et  al.,  2016;  Teferra  et  al.,  2015; Tran et al., 2018; Widyatuti et al., 2018). Additionally, the World Health Organization reported 22 million girls aged 15 to 24 years experienced unplanned pregnancies in 2014 and a worldwide increase in number of unsafe abortions from 19.7 million in 2003 to 21.6 million in 2008, almost all in developing countries (Shu et al., 2016; WHO, 2011).

As in other Asian countries, Vietnam has a strong norm that prohibits premarital sexual contact. Nonetheless, the customary attitude has been changing due to a multifactorial impact (Gibbs et al., 2014; Shu et al., 2016; Xu et al., 2019; Yip et al., 2013). Declining influence of family, increasing urbanization, migration and the exposure to social network have collectively contributed to major changes in social and sexual behavior among adolescents (Gibbs et al., 2014; Shu et al., 2016; Tran et al., 2018; Xu et al., 2019). A nationally representative sample of youth aged 22 to 24 years using a self-administered questionnaire found that 33% of men and 4% of women in urban and 26% of men and 3% of women in rural areas admitted premarital sex (Ghuman et al. 2006).

Sexual activity is easily initiated when young people are still physically, emotionally, and cognitively developing while living away from home without family monitoring (Regassa et al., 2016; Yip et al., 2013). Systematic information on any changes that have occurred in the prevalence and context of premarital sexual activity would help provide an insight into the relationship among social and economic change, premarital sexual behavior and the transmission of STDs. However, not only is there a lack of reliable evidence that the prevalence of premarital sex is rising in Vietnam, but there is little information regarding the context and associated factors of premarital sex (Ghuman et al., 2006). This is a significant gap in the national data. This study was, therefore, conducted to investigate knowledge, attitude and practice of premarital sex among the subpopulation of bedsit-living students in Hue city and their associated factors.

Study design

A community-based, cross sectional sexual survey was carried out in Hue city, Vietnam in 2015. Hue is a sub-metropolitan city, in the Central Vietnam and located there, is a regional university, meaning that the city is home to thousands of immigrated students of both undergraduate and graduate levels. The target group was immigrated students who were living in rented accommodation in Hue city. Multi-stage cluster sampling method was used (Azmawati et al., 2017; Widyatuti et al., 2018). The city has 27 urban wards. In stage 1, 5 wards with high density of residential bedsits close to Hue university schools were selected. Houses and households listing for selected wards were obtained with the assistance of local government. There were 1364 registered bedsits which were homes to 21810 students. In stage 2, 146 bedsits were randomly selected and all residing students aged 18 to 30 years  were  asked to enroll in this survey, except for foreign students. Data were collected by using a self-administered questionnaire at participant’s room to create favorable conditions. Six trained staff members from the Faculty of Public Health, Hue University of Medicine and Pharmacy followed up the data collection process closely.

Sample size

Sample size was calculated based on a previous publication which reported 38.8% students considered premarital sex (Thi et al., 2012). Therefore, the estimated size was:

Enrolled participants were divided into 2 age groups, 18 to 20 and 21 to 30 for further evaluation of associated factors.

Statistical analysis

Continuous data were presented as mean ± standard deviation and categorical data were given as counts and percentages. Pearson’s Chi-squared test was used to ascertain the association between knowledge, attitude, practice of premarital sex and gender, age group, marital status. All analyses were performed using SPSS 18.0 software. P values < 0.05 indicated statistical significance for all comparisons.

Ethical clearance

Ethical standing and protocol of this study were approved by the institutional review board of Hue University of Medicine and Pharmacy. Participants reserved the right to take part in the survey and were not required to declare name, age or personal information. Written consent was obtained from all participants. 

Knowledge, attitude and practices of premarital sex

Seven hundred and thirty bedsit-living students including 323 men (44.2%) and 407 women (55.8%) agreed to participate in the survey. The mean age was 20.9 years (range, 18 to 30 years). Among these, 87 respondents (11.9%) had experienced premarital sex at an average age of 19.8 ± 2.2 years (range, 14 to 25 years), including 60 men and 27 women. In this subset of premarital sex, 80/87 individuals (91.9%) admitted using contraceptives (65.5% used frequently and 26.4% used unfrequently) and 7/87 (8.1%) claimed never use contraceptives. Types of contraceptive were condom (93.8%), birth control pills (26.3%), emergency contraceptive pills (8.8%), calendar based (2.5%) and withdrawal (1.3%). Eleven participants (12.6%) reported pregnancy, of these 9 decided to terminate the pregnancy by abortions. Knowledge and attitude toward premarital sex of respondents was summarized  in  Table 1. Men  were  less  knowledgeable than women in terms of consequences of premarital sex (p < 0.001, x²). Premarital sex was refused by 65.9% of participants whilst 34.1% agreed on different situations, in which 21.4% accepted if it is consensual and 6.7% accepted if understanding contraceptives.

There were 346 (47.4%) and 384 (52.6%) students in the age groups of 18 to 20 years and 21 to 30 years, respectively. Participants of the age group of 21 to 30 years had higher rate of knowing consequences of premarital sex, accepting premarital sex and practicing premarital sex than those in the age group of 18 to 20 years (89.8% vs. 83.2%, 35.7% vs. 32.4% and 16.4% accepted premarital sex more than female students did (45.8% vs. 24.8%, p < 0.001, c²). Associated factors of attitude and practice of premarital sex were summarized in Tables 2 and 3.

Associated factors of premarital sex

Gender, age group, marital status, knowledge of consequences of premarital sex and knowledge of STDs prevention were associated with attitude toward premarital sex (p < 0.05, c²). Similarly, gender, age group, marital status, knowledge of consequences of premarital sex and attitude toward premarital sex were associated factors of practice of premarital sex (p < 0.05, c²).

This study addressed a specific subpopulation of students living in rented accommodation who were generally considered more susceptible to unsafe sex. As a result, 11.9% of students admitted premarital sex, a rate which was in line with recent domestic and regional data, yet lower than those of Africa, West Asia and developed countries (Adhikari and Tamang, 2009; Azmawati et al., 2017; Do and Fu, 2010; Lou et al., 2012; Rathavuth, 2009; Song and Ji, 2010; Tangmunkongvorakul et al., 2012; Thi et al, 2012a; Tran et al., 2018; Yip et al., 2013). However, this prevalence seems to be higher than that of the previous national data ((Ghuman et al. 2006; Mensch et al., 2003). This finding implies a trend of increased popularity of premarital sex among students, particularly those living away from family. Traditionally for most Asian people, particularly women, the onset of sexual activity coincides with marriage. However with rising ages  of marriage and changing sociocultural norms, young people have more liberal attitude toward premarital sex with an increasing number of sexual activity before marriage (Cai et al., 2013; Do and Fu, 2010; Gibbs et al., 2014; Htay et al., 2010; Katayon, 2014; Motamedi et al., 2016; Mudassir et al., 2010; Philippines, 2014; Shu et al., 2016; Song and Ji, 2010; Tangmunkongvorakul et al., 2011; Xu et al., 2019; Yip et al., 2013).

 We found that male students were more sexually active than their female counterparts (69% vs. 31%). This finding was also in keeping with previous data as men have more permissive attitudes towards premarital sex than women (Adanikin et al., 2017; Berhan and Berhan, 2015; Motamedi et al., 2016; UNFPA, 2015; Xu et al., 2019; Yip  et  al.,  2013),  probably  because  men have greater freedom to be involved in sexual relation (Motamedi et al., 2016). Some studies suggest that young men and women engage in premarital sex in different circumstances. Men are more likely influenced by pleasure, recreation and peer pressure and impulsivity whereas women are driven by emotion (Gibbs et al., 2014; Motamedi et al., 2016). Thus, while young women tend to accept their first sex with a committed relationship or with a partner they planned to marry, young

men are more likely to have sex with a casual partner or sex worker (Nguyen and Liamputtong, 2007; UNFPA, 2015). However, this pattern appears to be changing in some settings as attitudes towards premarital sex among young women become more permissive, meaning that more young women (33%) and men (42%) were supportive  of  sexual  activity   in   the  context  of romantic relationships (Motamedi et al., 2016; Shu et al., 2016; Tangmunkongvorakul et al., 2011; Yip et al., 2013).

 In Vietnam, achievements from the large-scale economic reform have had great impact on the national socioeconomic status (Gibbs et al., 2014; Tran et al., 2018). People have more freedom to make their own choice and more contacts with Western culture. In addition, parents seem to lose some of their control over their children when they become financially independent (Nguyen and Liamputtong, 2007).  Internet and social networks have been widely used as a space to learn about sexual relationships (Azmawati et al., 2017; Gibbs et al., 2014; UNFPA, 2015). As a result, young people have more permissive attitude toward dating and premarital sex than their older counterparts   (Lou   et   al.,   2012;   Nguyen  and Liamputtong, 2007; Shu et al., 2016; Xu et al., 2019; Yip   et al., 2013). In this survey, we observed an interactive association between attitude and practice of premarital sex with gender, age group, marital status and knowledge of premarital sex. This finding was similar with a domestic report (Thi et al., 2015b).

In some settings, young people who are out-of-school are also more likely to engage in premarital sex (Azmawati et al., 2017; Yip et al., 2013). A study of urban adolescents aged 17 to 20 in Thailand reported that 90% of out of school boys and 53% of out of school girls had commenced sexual activity, compared with 33 and 15% who were still at school, respectively (Tangmunkongvorakul et al., 2012). Another study of dropout college students in Nigeria found 73.9% students had full sexual intercourse (Adanikin et al., 2017). In Cambodia, 18% of young men in urban areas have had premarital sex compared with 6% in rural areas (Rathavuth, 2009).

Family monitoring has been proved a protective factor against unsafe sex (Azmawati et al., 2017; Widyatuti et al., 2018). A lack of parental support or family attachment has been associated with early initiation of sex (Motamedi et al., 2016; Shu et al., 2016; UNFPA, 2015; Yip et al., 2013). While religious taboos may be a barrier limiting open discussion of sexual health and access to services, a family’s religious or spiritual beliefs can also be protective against risky sexual behaviors (Azmawati et al., 2017; Chamratrithirong et al., 2010). Peers are also a strong influence on young people’s attitudes and behaviors, especially among men (Akibu et al., 2017; Azmawati et al., 2017; Gibbs et al., 2014). Additionally, a perception that the majority of friends or peers are already having sex increases pressure on young people, and has been  associated  with  early  sexual  initiation  in many countries including Vietnam (UNFPA, 2015).

Premarital sex itself is not necessarily a risk factor for poor sexual and reproductive health. As adolescents grow up and mature, increasing interest in sex and sexual experimentation are a normal part of physical and mental development. Therefore, young people who are equipped with knowledge of safe sex and access to services can have healthy, positive sexual relationships (UNFPA, 2015). Increase capacity in youth sexual and reproductive health program and service delivery is warranted. Understanding how youths made decisions to engage in early sexual activities is critical for intervention efforts aimed at fostering positive youth development and decreasing the negative outcomes of youth sexual behavior.

This study has several limitations. The relative homogeneity of the study population in terms of occupation, educational background, generation and living condition may affect generalization. In addition, small sample sizes recruited from a single community, inaccessibility of other associated factors such as sexual health education, peer influence, family socio-demographic were also consistent limitations.

The prevalence of premarital sex among the subset of bedsit-living students was comparable with national and regional data. Up to one-fifth of the studied population were not well equipped with knowledge of safe sex. Gender, age group, marital status and knowledge of consequences of premarital sex were associated factors of attitude and practice. The present study also provides evidence   that   knowledge,  attitude   and   practice   of premarital sex are connected. Reproductive and sexual health education for immigrated students should be reinforced. The intervention effort has to focus on the risk factors among this subset and provide them with convenient, optional and accessible services.

The authors have not declared any conflict of interests.