Sweet 16 and never been kissed?
Experiences from a longitudinal Norwegian study.

Mailing address:

Professor Bente Træen
University of Tromsø
Department of Psychology
NO-9037 Tromsø
Norway

Phone: 00 47 77 64 59 55
Fax: 00 47 77 64 56 10

e-mail: bentet@psyk.uit.no

The purpose of this study was to analyze various sexual debut ages in a longitudinal sample of Norwegian adolescents. Specifically, the paper addresses the age at which adolescents first experience various sexual activities, and whether there are gender differences in these sexual debuts? The participants in this study were 261 adolescents followed in three questionnaire surveys over a period of 1½ years (1999-2001). The results showed that boys started to masturbate, and had their first orgasm, significantly earlier than girls had. Boys also initiate body touching with partners earlier than girls. Girls first have sexual intercourse with older males, and conversely, boys have sexual intercourse with younger or same age females. Apart from this, age of onset for other types of sexual activities appeared similar for boys and girls.

Introduction

Human sexuality is shaped by cultural context and historical period. In interaction with their culture and society, people learn and internalise sexuality’s various expressions. Nordic sexual culture is different from that of the majority of other Western societies and cultures (Lewin et al., 2000; Kvalem & Træen, 2000). These differences in sexual culture are historically rooted, and connected to a well-integrated ideology about equality between individuals, and groups of individuals. Due to this historical development, there are probably less social restrictions upon adolescent sexuality, and in particular female sexuality, in the Nordic countries compared to other Western countries. Most adolescent boys and girls in Norway, as in the other Nordic countries have their first intercourse when they feel mature enough for sex (Træen & Kvalem, 1996a; Kvalem & Træen, 2000; Helmius, 2002). Feeling mature enough for sex is related to being in love, and having a committed relationship, which has lasted for some period of time, usually some months.

Representative, national surveys on sexual behavior in Europe and the US carried out during the past 10-15 years show that there has been a change in the reporting of age at coital debut (Bozon & Kontula, 1998; Teitler, 2002; Kontula, 2003). This change in age at first coitus was first noticed in the Nordic countries, then in several of the Western and Central European countries, and a generation thereafter in Southern and Eastern Europe. A comparison of coital debut age based on self-reports among European men shows little variation from country to country, and over time. The situation among women is different. Since the 1960s the reporting of coital debut age among Western European and US women fell by two to three years (Teitler, 2002). This does not alter the fact that in the majority of European countries, and in the USA (Sugar, 1995), boys still report having their coital debut at an earlier age than girls. Young Finnish, Swedish, Icelandic, Norwegian, Danish and German girls on the other hand, have reported to experience coitus at an earlier age than boys (Schmidt, Klausman, Dekker & Matthiesen, 1998; Edgardh, Lewin & Nilsson, 1999; Bozon & Kontula, 1998; Helmius, 2000; Kontula, 2003; Pedersen, Samuelsen & Wickström, 2004). Kontula (2003) points out that from a gender perspective two clear-cut profiles stand out. One is the double standard in the South of Europe, and the second is the egalitarianism of the North and a handful of other countries. In the south of Europe, premarital female sexuality is subject to more restrictions and social control compared to the Nordic countries.

Sexual experiences are collected step by step and the coitus is merely one of several experiences in this regard (Jakobsen, 1997; Edgardh et al, 1999; Schwartz, 1999; Gates & Sonenstein, 2000). In early childhood, children start masturbating (Sugar, 1995). Continuing their sexual exploration, children interact with other children and also engage in sexual games, such as playing “doctor” and “patient” (LeVay & Valent, 2003, p. 379). While playing these games, children can explore the body’s secrets and start getting to know their own feeling of arousal and desire without the interference of adults. In their early teens, adolescents enter into couple relationships. In the Nordic context, society does not tolerate younger teenagers having extensive sexual experiences (Helmius, 2002). Sexual activity is more limited to non-coital activities such as kissing, touching of the body and genitals (Jakobsen, 1997; Pedersen & Samuelsen, 2003). Thus, one very important purpose of these early relationships is that the adolescents learn what it is like to be treated as part of a couple contrary to being single. Nordic sexual culture accepts that older teenagers have sexual intercourse and oral sex, provided they follow the love ideology and act responsibly and use contraception (Kvalem & Træen, 2000; Kvalem, 2002). Emotional and sexual engagements are important to the majority of Nordic adolescents when they enter into more mature forms of couple relationships (Træen & Kvalem, 1996a; Helmius, 2002). However, the issue of when coital and non-coital experiences occur for the first time remains relatively unexplored. Based on this background, the purpose of this paper is to estimate the median debut age of kissing, French kissing, touching of the body, masturbation, orgasm, coitus and oral sex in a longitudinal sample of Norwegian adolescents. When do they experience the different sexual activities for the first time? Are there gender differences in the reporting of sexual debut ages?

Methods

Participants

The data used to answer the research question was gathered using a longitudinal survey originally designed to evaluate the effect of a sex education intervention program. The intervention itself, its effects on contraceptive behavior, research design and dropout, has been described elsewhere (Træen, 2003). In 1999, a stratified sample of 74 compulsory schools, comprising 2717 pupils (in the 10th grade), was drawn at random from all compulsory schools in the county of Nordland in Northern Norway. Each school was randomly assigned to one of four conditions in a Solomon four-group design, that is as a randomized, prospective intervention study (Campbell & Stanley, 1966). Several schools declined to participate until they were told to which group they were assigned. By October 1999, a total of 54 schools were willing to participate in the study. With schools as units of randomization, this yields a response-rate of 73.0%. Before participation, all 2053 pupils from the 54 schools had to give their informed consent. Only 1183 adolescents, 533 boys and 650 girls, gave their consent (57.6%). As the schools are not allowed to hand out lists of their pupils' names, we are not able to make a comparison between participating and non-participating pupils on variables such as gender and academic performance.

Procedure

Within the Solomon-Four-Group design, only half of the schools in the intervention and control groups received the pre-test (October 1999). All pupils were asked to fill out two post-test questionnaires, the first 6-7 months after the pre-test (May 2000) and the second 1 1/2 years after the pre-test (May 2001). The questionnaires at the baseline and the post-test 1 were handed out directly to the pupils in the classrooms. Each pupil filled out the questionnaire at home, and after filling it in the questionnaire was put in a sealed envelope. Teachers gathered the sealed envelopes they received from all the pupils in the class, and returned them collectively to the National Institute of Public Health by mail. At the second post-test, questionnaires were sent out directly to the pupils’ home address, and returned by mail. On all three occasions one reminder was mailed after 2-3 weeks.

The mean age of the adolescents who responded to the pre-test questionnaire in 1999 was 14.9 years. At the first post-test in 2000 the mean age of the respondent was 15.5 years, and at the second posttest in 2001 the mean age was 16.4 years.

The questionnaire

The questionnaire contained 99 questions, most of them previously used in other Norwegian, Swedish and Scottish sexual behaviour studies among adolescents. Questions about social background, questions on lifestyle, use of alcohol/drugs, sex education, motives for intercourse (Træen & Kvalem, 1996a; 1996b; The Share questionnaire, 1998), self-perception, sexual knowledge and attitudes towards sexuality (Lewin & Helmius, 1983), were included in the questionnaire. The questionnaire also contained questions about use of contraception at the first/most recent occasion of sexual intercourse, contraceptive self-efficacy scale (Bandura, 1977; Levinson, 1986; Kvalem & Træen, 2000), questions about emotional reactions in specific sexual contexts, sexual debut ages and number of coital partners.

Response

As school was the randomising unit, the formally correct way to analyse the data is to use schools as the units of analysis. However, due to large variations in the number of pupils in each school (varying from 10 to 103 pupils) this procedure was difficult to apply. For this reason it was decided to use the individual as units of analysis. Treating individuals as unit of analysis may represent a problem, as school differences are ignored. There may exist differences between the schools in the dependent variables that cannot be explained in terms of the different characteristics of the pupils who attend those schools. However, a previous study showed no effect of schools upon variables related to use of contraception (Træen, 2003).

Within the frame of this project, three data collections were carried out. Based on the 1183 received informed consents, 613 pupils were assigned to the pre-test groups. This is the study population for this paper. The response to the pre-test was 85.3% (523 of 613). The response rate was 90.4% (291 of 322) among girls, and 79.7% (232 of 291) among boys. At post-test 1 the response rate was 76.5% (905 of 1183); 84.4% (548 of 649) among girls, and 67.0% (357 of 533) among boys. Ten pupils had moved to new addresses by the time of the second post-test and could therefore not be reached. The over-all response rate at post-test 2 was 56.4% (662 of 1173). The response rate at post-test 2 was 67.1% (433 of 645) among girls, and 43.4% (229 of 528) among boys.

The study population

Only 261 of 613 adolescents (90 boys and 171 girls) responded to all three data collections (42.6%). Only these adolescents are included in the analyses in this study. The mean age of the adolescents in our sub-study was 14.9 years in 1999, 15.5 years in 2000, and 16.4 years in 2001.

Measures

Debut ages - were measured by the question Have you ever together with a boy/girl… Kisses/ had French kissing /been touched all over the body by the partner /yourself touched the partner all over his/her body /Touched his/her genitals with your hands / Touched his/her genitals with your mouth. The response categories were 1 = No and 2 = Yes. Each question was followed by the sub-question if yes: Age first time. Masturbation was measured by the question Have you ever satisfied yourself sexually (masturbated)? Ejaculation/orgasm was measured by the question Have you ever had an ejaculation/orgasm? The response categories were 1 = Don’t know, 2 = No and 3 = Yes. The questions were followed by the sub-question If yes: Age first time.

Age difference between partners – the variable was created as the difference between the respondent’s reported age at first coitus and the reported age of the partner at this occasion. The new, continuous variable was recoded into the categories 1 = 1-2 years younger, 2 = same age, 3 = 1-2 years older, and 4 = 3+ years older.

Statistical analysis

At the time of the second posttest, not all adolescents had experienced the various sexual actions. For this reason, data must be treated as right-censored survival, or (more generally) time to event, data. The probability of (not) having experienced each of the sexual actions before different ages could be estimated by means of Kaplan-Meier curves, and the median debut age as the age when this curve crosses the value 0.5. Testing for differences between boys and girls were carried out by log-rank tests. In the questionnaire, the debut ages were reported in whole years. However, it is not very likely that the adolescents had their sexual debuts on their birthdays. Software for Kaplan-Meier estimators will then typically treat the data as if all events took place at the adolescents’ birthdays. More likely, the events took place somewhere in the age intervals of length one year. In order to adjust for such times in the data, random numbers between 0 and 1 were added to the censored event times (Hosmer & Lemeshow, 1999; Kleinbaum, 1997; Samuelsen, Wisløff, & Skrondal, 2005). In the debut age analyses we use event times reported in posttest 2.

Results

Table 1 shows the percentages reporting experience of various sexual activities at the three points of time for data collection, by gender. At the time of the pretest, a significantly higher percentage of girls than of boys reported experience of French kissing. A statistically significantly higher percentage of boys than of girls reported experience of having touched a partner all over his or her body, of having touched a partner’s genitals by hands, experience of masturbation and of ejaculation or orgasm. The percentage of adolescents reporting sexual experiences increased over the time span. There were more differences in the reporting between boys and girls at the pretest than at posttest 2. At all three points of time, a statistically significant higher percentage of boys than of girls reported having masturbated and having had an ejaculation or orgasm. There were no statistically significant gender differences in the reporting of intercourse and oral sex experience.

Median debut ages were estimated at posttest 2 by means of Kaplan-Meier estimators. To obtain medians, the estimated proportion with an event needs to be at least 50%. In order to achieve this on all events, data from posttest 2 were used.

The sexual debut ages of adolescents are shown in Table 2. The debut ages are presented in terms of medians and confidence intervals (CI). A narrow confidence interval indicates that the result is precise. Among boys, the estimated debut ages were in ascending order: kissing and masturbation, ejaculation/orgasm, French kissing, having been touched all over the body by partner, having touched partner’s body all over, touched partner’s genitals with the hands, coital experience, and oral sex. The debut ages in girls were in ascending order: kissing, French kissing, masturbation, having been touched all over the body by partner, orgasm, having touched partner’s body all over, touched partner’s genitals with the hands, coitus and oral sex.

Figures 1 tnrough 9 (see table 2) show the plots of the Kaplan-Meier curves for the different debut ages. The curves also show the proportion of adolescents who have not made the debut at a certain point of time. The faster the curve approaches zero, the faster the debuts occur.

Statistically significant gender differences were found for masturbation and orgasm. Girls started to masturbate 2.2 years later than boys, and had their first orgasm 2.6 years later than boys. On average, 0.6 years elapsed between first masturbation and first orgasm in boys. Girls used 1 year to achieve the same.

The adolescents were asked to report the age of their first coital partner (Table 3). The reporting of partner’s age may not be as precise as the reporting of own age. Nevertheless, the majority of boys had their first coitus with a partner 1-2 years younger (31.3%) or the same age as themselves (33.3%). The majority of girls had their first coitus with someone 1-2 years older (32.7%) or 3 years or more (45.5%) older than themselves. The boys’ first coital partners were reported to be 0.2 years younger (mean) than the boys themselves and the girls’ coital partners 2.9 years older (mean) than the girls themselves. A total of 77.8% reported they were in love with their first coital partner (73.5% of the boys and 79.8% of the girls; p > .05), and 75.9% had known the partner for more than a month (71.4% of the boys and 78.0% of the girls; p > .05) , and 24.1% for less than a month, prior to the first coitus. A total of 84.8% of the boys and 89.5% of the girls who were in love with their partner had known the partner for more than a month. For girls, the correlation between being in love and time known the partner prior to intercourse was 0.40, and the corresponding figure among boys was 0.34. This indicates that most adolescents may have been in a committed relationship with the partner before their first coitus. There were no gender differences in this respect.

Discussion

The aim of this study was to contribute to the body of knowledge about sexual debut ages and thereby sexual development, in boys and girls. The results showed that over a period of one and a half years the majority of the adolescents engaged in a variety of sexual experiences. Over the time period, there were few gender differences in the reporting of debut ages.

As our sample is not a representative one, we must be careful not to generalize the results to the general population of adolescents in this particular county. In a representative, longitudinal study conducted in 2002 among Norwegian adolescents, the median coital debut age among girls was estimated to 17.3 years and 17.9 years among boys (Pedersen et al, 2003). The coital debut age in the region North-Norway (3 counties) was estimated to 16.8 years in girls (95% CI 16.3-17.5) and 17.3 (95% CI 16.8-17.9) years in boys. The coital debut ages found in this study were thus somewhat lower, but the estimates were within the confidence intervals of the other study. This indicates that our results are likely to reflect the coital debut age of adolescents in the north of Norway.

We found no statistically significant gender difference in the reporting of coital debut age, a finding also reported in a recent cross-cultural review paper by Teitler (2002). A recent Norwegian study showed that the coital debut and the oral sex debut seem to occur about at the same time (Pedersen & Samuelsen, 2003). Our study points in the same direction, although intercourse is reported slightly earlier than oral sex. According to Lewin (1987), oral sex in the Nordic context is not likely to be a substitute for, or a step on the way to, the coitus. It is more likely an activity of variation and renewal for those already coitally experienced.

On average, boys reported their first coital partner was 0.2 years younger than themselves. The girls’ partners were 2.9 years older than themselves. This indicates that the majority of the adolescents – particularly the girls - have sexual intercourse with partners who are not included in our study. It is likely that the customary roles of couple formation in most Western countries tend to imply that the boy should be some years older than the girl (Helmius, 2000; Teitler, 2002). When the majority of the girls in our study are occupied with older boys, this may make it difficult for our boys to find a partner the same age to enter a couple relationship with. They may also have difficulties finding a 2-3 years younger partner, who also feel mature enough for sex (Helmius, 2002). Among other options, this may imply that boys can have sexual intercourse without emotional involvement when having the possibility to, or they can enter into a couple- relationship at a less mature level with a younger girl who does not feel mature enough for sex.

One interesting gender difference found in this study was the sequence by which sexual experiences occurred. After the initial experience with kissing, boys seemed to spend time on auto-sexual activity, in addition to having partner-sex. Girls seemed to have sexual activity with a partner rather than practicing auto-sexual activity. This may be a reflection that more girls than boys this age have the opportunity to form part of couple relationships, which includes petting activities. Girls may not find auto-sexual activity necessary when they are in a relationship with a partner (Helmius, 2000). We do not have any knowledge about the extent to which girls discuss masturbation with their peers. If masturbation is little discussed, this could have an impact on their behavior. Another explanation for the gender difference may be connected to body satisfaction.

Body dissatisfaction is shown to be associated with the development of eating disorders and depression, especially among young women (van den Berg, Wertheim et al., 2002 ; Striegel-Moore & Franko 2002 ; Polivy & Herman 2002) . There also seems to be an association between body dissatisfaction, negative self-esteem, and sexual problems (Pruzinsky & Cash 1990) . The literature on the relationship between body dissatisfaction and sexuality is limited. A study by Wiederman and Pryor (1997) showed that body dissatisfaction predicted lower incidence and later onset of masturbation in women with eating disorders. Girls tend to be more dissatisfied with their own bodies than boys do (Kvernmo, Johansen, Spein & Silviken, 2003). This may, in turn, be one reason why they start to masturbate later than boys do.

At the time of the pretest, more boys than girls reported having been active in touching a partner all his or her body. Other studies have also shown that young boys tend to be more active and take initiative more often than girls do (Henriksson & Lundahl, 1993). However, in older teenagers this behavioral pattern is likely to have changed the past years. Recent Norwegian research findings among young adults indicate that women are active and do take sexual initiative (Pedersen & Blekesaunet, 2003). However, the same may not apply to younger teenagers. At time of the pretest the mean age of the adolescents was 14.9 years. At this young age, girls may not have learned sufficient skills to enable them to be, or dare to be, sexually active and initiative taking (Træen & Kvalem, 1996a). Another explanation concerns the ambivalence that may be connected to girls’ role as a sex partner. Henriksson & Lundahl (1993) found that boys appreciate qualities in their female partners, such as being active and taking the initiative. Girls are likely to have knowledge about this preference. However, there may be a gap between knowledge and behavior at this young age. A girl may fear that if she exposes herself as active and initiative taking, she runs a risk of being perceived by her partner as being too sexually experienced, that is as a girl with a past. Most likely, the girl does not want to project this image of herself to her partner. As a consequence, she may prefer the passive strategy.

A study among 18-49 year olds in the Norwegian capital, Oslo, in 1997 showed that the age at first masturbation, particularly among women, has decreased during the past couple of decades (Træen, 1998). This is also found in Sweden (Helmius, 2000). However, men/boys still make their debut far earlier that women/girls. These findings support the results from this study. Boys start to masturbate earlier in life than girls do, and they also have their first orgasm at an earlier age. It is likely that some of the gender differences in the reporting of orgasm are due to the male nocturnal emission. Both for girls and for boys, the first orgasm occurred some time after they had started to masturbate. For boys, the first orgasm occurred 0.6 years after the initiation of masturbation. The time span between masturbation debut and orgasm debut in girls was 1 year. Girls may not practice to obtain orgasm as frequently as boys do. According to Baumeister (2000), men and women are different in erotic plasticity. Compared to men, the female sex drive may be more influenced by psychological, social and cultural factors.

Two decades ago, girls became familiar with their own sexuality later than boys did, and often after they had initiated a sexual relationship with a partner (Lewin & Helmius, 1983). In past decades the focus on the positive aspects of female sex pleasure has been strongly emphasized in the mass media such as women’s magazines, newspapers, radio and TV. There is evidence that Norwegian girls who appreciate their own sexuality are better users of contraception than others (Træen & Kvalem, 1996b). The health authorities have encouraged young girls to learn to know and appreciate their sexuality. They are encouraged to explore the body’s potential, not for the sake of the partner, but for their own sake. However, women may be faced with a conflict of roles. The traditional female gender role advocates a focus toward the needs of others (Helmuis, 1990). A modern gender and sex-specific role is more oriented toward one’s own pleasures (Pedersen & Blekesaunet, 2003). The traditional and the modern roles may create a conflict of interest. Even so, it can be expected that the development of gender equality in the area of sexuality will continue (Lewin et al, 1997). This means that for the coming generations the social restrictions upon, and social acceptance of, male and female sexuality should become more similar.

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Table 1. Sexual Experiences in a Longitudinal Sample of Norwegian Adolescents (percentages)

Table 2. Age at First Experience of Various Sexual Acts in a Longitudinal Sample of Norwegian Adolescents 2001 (Kaplan-Meier survival analysis, and confidence intervals (CI)). Click on link to see K-M curves.

Table 3. Age Differences Between the Partners on First Occasion of Sexual Intercourse as Reported by a Longitudinal Sample of Norwegian Adolescents, by Gender (percentages)

Note. Tested for statistical significant gender differences by means of Chi-square (47.914; 3 d.f, p < 0.001)

Note: The group of adolescents who participated in all three surveys was selected to check for possible effects of the intervention. No statistically significant effects of the intervention was found on age at first occasion of coitus, oral sex, masturbation, orgasm, and touching of body and genitals.