Indian Journal of Dermatology
: 2022  |  Volume : 67  |  Issue : 5  |  Page : 625-

The Sexual behavior and protective conduct among university students in Germany - Chances and approaches to tackle spread of sexually transmitted diseases

Corbinian Fuchs, Niklas Teichert, Katharina Neu, Benjamin Clanner-Engelshofen, Stefan Zippel, Lars E French, Markus Reinholz 
 Department of Dermatology and Allergology, University Hospital, LMU Munich Frauenlobstr, 9-11, 80337 Munich, Germany

Correspondence Address:
Markus Reinholz
Department of Dermatology and Allergy, University Hospital, LMU Munich, Frauenlobstr, 9–11, 80337 Munich


Background: Current case numbers of sexually transmitted infections (STIs) in Germany are continuously increasing. Young adults aged 19–29 appear to be especially at risk and are therefore the demographic of ever-growing importance for future prevention work. Objective: The aim of the survey was to analyze awareness and protective behavior regarding sexually transmitted infections with a major focus on condom-usage by university students in Germany. Method: The collection of data was based on the conduction of a cross-sectional survey for students of Ludwig Maximilian University of Munich, the Technical University Munich, and the University of Bavarian Economy. The survey was distributed via the professional online survey tool “Soscy” and was thus performed completely anonymized. Results: Within this study, a total of 1,020 questionnaires were collected and consecutively analyzed. In terms of knowledge about human immunodeficiency viruses (HIV), over 96.0% of participants were aware that vaginal intercourse can be a source of transmission for both sex partners and that condom use can be preventive. In contrast, 33.0% were unaware that smear infections constitute a crucial transmission route of human papillomaviruses (HPV). Concerning protective behavior, 25.2% either rarely or did not use a condom in their sexual history, even though 94.6% agreed that condoms protect against STIs. Conclusion: This study outlines the importance of education and prevention work that focuses on STIs. Results might reflect effectiveness of previous education efforts made by several prevention campaigns targeting HIV. On the downside, knowledge of other pathogens that establish STIs appears worthy of improvement, especially considering the partially risky sexual behavior observed. Therefore, we see a strong need to reform education, guidance, and prevention strategies in a way that emphasizes not only all pathogens and connected STIs equally, but also a differentiated presentation of sexuality providing appropriate protection strategies for everyone.

How to cite this article:
Fuchs C, Teichert N, Neu K, Clanner-Engelshofen B, Zippel S, French LE, Reinholz M. The Sexual behavior and protective conduct among university students in Germany - Chances and approaches to tackle spread of sexually transmitted diseases.Indian J Dermatol 2022;67:625-625

How to cite this URL:
Fuchs C, Teichert N, Neu K, Clanner-Engelshofen B, Zippel S, French LE, Reinholz M. The Sexual behavior and protective conduct among university students in Germany - Chances and approaches to tackle spread of sexually transmitted diseases. Indian J Dermatol [serial online] 2022 [cited 2023 Mar 21 ];67:625-625
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Sexually transmitted infections (STIs) form a heterogenous group of infections whose common clinical feature is transmission through various sexual contacts; most notably the human immunodeficiency virus (HIV) potentially leading to the Acquired Immuno-Deficiency Syndrome (AIDS).[1],[2] Other diseases in the field of sexually transmitted infections include syphilis, hepatitis B, human papillomavirus (HPV), chlamydia, gonorrhea, herpes genitals, and trichomoniasis. In the context of HPV prevention, adolescents and young adults play a decisive role, as the highest chance of avoiding infection lies in this demographic.[3],[4]

While the prevalence of HIV in Germany remained constant within last ten years and mortality has decreased steadily as a result of progress with antiretroviral therapy, the incidence of HIV and other STIs is now again increasing.[5],[6] For instance, in 2019, 2600 people in Germany and 1.7 million people worldwide were tested HIV-positive.[6] Main transmission routes are connected to MSM (men who have sex with men), followed by heterosexual contacts, and shared drug use.[1],[6],[7] Young people and adolescents, e.g., university students, were linked to frequent and changing sexual contacts, therefore putting them at higher risk of transmission.[8],[9],[10],[11]

According to reported data, there is little protective behavior during sexual activity among college students[10],[12],[13],[14],[15] despite their knowledge of HIV transmission appearing to be solid.[15],[16] One explanatory approach is a commonly low perception of personal vulnerability regarding the risk of infection.[17],[18],[19],[20] Moreover, the knowledge among adolescents about other STIs and associated transmission routes is often reported to be very limited,[10],[15] potentially being linked with an underrepresentation in German prevention campaigns, which have focused primarily on HIV in past decades.[21] Those misconceptions and under-valued personal infection risks can lead to insufficient condom use and increasing STI infection rates.[10],[11],[20]

To further elaborate the level of knowledge and protective behavior, we conducted an online questionnaire among 1020 students from three major universities in Munich (Ludwig Maximilian University of Munich, Technical University of Munich, University of Bavarian Economy, Munich). Strong emphasis was placed on condom use and its correlation with sociodemographic variables. We aim to assess the current knowledge and identify reasons of rare condom use in order to develop new educational strategies as well as suitable prevention work for university students and adolescents.


From December 2020 to February 2021, we conducted a cross-sectional anonymous online survey in German language, which achieved an approximate response rate of 72.25%. The research framework was built on evaluating the current knowledge of STIs as well as the protective sexual behavior of university students in Munich. Special attention was paid to ensuring the delimitation between HIV and other STIs, being of viral, bacterial, as well as parasitic origins.

Based on previous research efforts in the field, e.g., Ashenhurst et al. (2016) and Aras et al. (2007),[9],[12] we assumed that around 50% of persons surveyed use condoms regularly. Thus, versatile questions about condom use were designed, in order to gain precise insights into our study group's application of protective sexual behavior. Qualitative observations described above were correlated with demographic data acquired to complement the study approach.

Statistical analysis

Metric variables were reported as mean values ± standard deviation (SD). Reported percentages refer to the applicable cases. Comparisons between the different demographic variables and the questions regarding condom use were made using the Kruskal–Wallis Test and the Mann–Whitney U Test. A P value of 0.05 or less was considered significant. Regarding the significance level, a power of. 9 and equal groups sizes given, a sample size of at least 900 was necessary for adequate analysis of small effects (d = 0.2). By even exceeding this case number, compensation of invalidly completed questionnaires was given and robustness of observations achieved. The case number was calculated using the program G*Power (Faul, 2009).

For individual substantiation of “other reasons”, the Kruskal-Wallis Test was followed by Dunn's Multiple Comparisons Test using GraphPad Prism version 8.4.3 for Windows, GraphPad Software, San Diego, California USA.

Ethics approval

The institutional ethics committee of the University Hospital (LMU/Munich) approved this fully anonymous survey with university students in Munich (project KB 20/028).

Questionnaire design

The survey was designed in a multiple-choice format and written in unbiased and non-persuasive language based on previous studies in the field of sexual education research. Knowledge assessment of human papillomaviruses, human immunodeficiency viruses, chlamydia trachomatis, and Neisseria gonorrhoeae, as well as associated diseases were considered the main focus. Additionally, questions targeting individual factors and risky behavioral patterns leading to condom relinquishment were included.

Consecutively, the questionnaire was reviewed by external sexual health experts and tested in a group of 21 subjects ensuring construct validity as well as test reliability.



Of a total of 1020 participants included in survey, 67.5% were female, 31.4% were male, and 1.1% were of diverse gender. Regarding sexual orientation, 85.2% indicated heterosexual, 8.5% bisexual, and 3.8% homosexual preferences. Other preferences or missing information composed the remaining portion of 2.5%.

Most participants reported Germany to be their country of birth (83.2%). The mean age was 23 years with a distribution from 17 to 46 years. On average, participants were sexually active since the age of 17.

In terms of religious affiliation, Catholic denomination was most common (41.2%), followed by people without any confession (29.9%), and Protestants (24.6%). Whereas almost half of the university students surveyed originally came from small cities with less than 20,000 inhabitants (41.9%), about 28.3% grew up in a city with more than 500,000 inhabitants. Regarding family circumstances, the majority (86.5%) were raised by their biological parents. Most of the participants (62.7%) enrolled in subjects that require state examinations for graduation, e.g., human/veterinary medicine or pharmaceutical sciences. Almost all others (29.6%) were currently enrolled in a bachelor's program, primarily at faculties of biology or chemistry.

Current knowledge

To assess the quality and range of knowledge about STIs, eight closed questions (agree/disagree) about transmission routes and protection strategies were included. In the field of HIV, over 96.0% of all participants agreed that vaginal intercourse can be infectious for both sex partners and that condom use can prevent infection. Similarly, 94.6% agreed that condoms also offer protection against other STIs, e.g., Gonorrhea. In contrast, about 13.0% were not aware of infertility being one potential consequence of chlamydia infection. Moreover, roughly a third (32.6%) were unaware that smear infections, which can also occur during sexual intercourse, constitute a crucial transmission route for human papillomaviruses.

To determine the sources of knowledge, interviewees could choose between several options and multiple selections could be made. While the internet was observed to be the main source of knowledge (77.6%), it was followed closely by the educational system (71.4%), talks (49.3%), friends (33.4%), and family (28.3%).

Condom Use

Almost three-quarters of the participants reported that they use condoms either always (41.1%) or most of the time (33.7%) for protection against STIs, whereas13.5% stated infrequent use and 11.7% use no condom at all. No significant difference between frequency in usage of condoms and demographical aspects, such as age, gender, religion, country of origin, family circumstances, size of the native community, or subject of study was found. When stratifying usage by indicated sexual preferences, homosexual interviewees were observed to use condoms significantly less frequently than participants who identified as bi- (P-value: 0.015) or heterosexual (P-value: 0.019).

Even though the largest portion of participants indicated “other reasons” (33.2%).

Among other factors commonly chosen by homosexuals, several others listed rather circumstances or emotions justifying previous incompliancy in condom-use.

Paradigmatically, 7.4% of students, mainly of male gender, stated that sexual intercourse without using a condom would lead to a superior feeling. On the other hand, 4.7%of predominantly female participants claimed that the influence of alcohol or drugs was the reason for not using a condom. Accordingly, either sexual desire or nonchalance prevailed any fear of potential STIs to be acquired in 4.0% of the cases and 2.7%, respectively, for the latter.

In terms of numbers, 47.3% of university students indicated repeated noncondom use in the past, while 40.9% admitted they were likely to continue the behavior in the future.

Individual substantiation of “other reasons”

Of a total of 1020 persons surveyed, 339 (33.2%) stated “other reasons” for not always having used a condom. Although their answers were mostly freely formulated, 317 could be further assigned into four main categories by analyzation of catchphrases. Only 22 participants withdrew and could not be analyzed due to lack of indication. 63 participants (6.2%) reasoned their condom-use behavior with an explicit monogamous sexual relationship including prior testing and were summarized in category 1.

Students who only stated prior testing (n = 25; 2.5%) were enrolled in category 2, whereas the main portion (n = 169; 16.6%) was assigned to category 3 by virtue of an expressly monogamous sexual behavior justifying former condom waive.

In contrast to the homogeneity within prescribed groups, which represent 25.2% of all students interviewed, category 4 (n = 60; 5.9%) includes all remaining subjects who did not meet the strict inclusion criteria and therefore depicts a very heterogenous collective.

Their reasons justifying no general condom-use, like a different, mainly birth control focused understanding of protection, a dependence on partner's virginity, technical and practical aspects of condom-use, including reduced erection, insufficient fitting or bursting, as well as a dependence of sexual orientation or sex practices applied (oral sex) are covering and reflecting the broad spectrum of sexuality. Further reasons given for not using condoms included birth-control focused understanding of protection, dependence on partner's virginity, technical and practical aspects of condom use (reduced erection, insufficient fitting or bursting), dependence on sexual orientation, and applied sex practices (oral sex). These reasons reflected a broad spectrum of sexuality.

However, since the categorization was based on the presence of catchphrases (positive selection) as prescribed above, the distribution of subjects among the categories strongly relies on their explicitness of indications. Therefore, a clear allocation cannot be guaranteed, and consequential final assessments might be limited.

Age and gender distribution

At the time of participation, subjects of all four categories were at comparable ages (mean age in years: C1: 22.6; C2: 22.6; C3: 23.3; C4: 23.1). Moreover, no significant differences were found between them regarding the age of first sexual contact (mean age in years: C1: 16.6; C2: 17.4; C3: 17.4; C4: 17.1).

Of a total of317 participants (31.1%) who stated “other reasons” for not always having used a condom, the gender distribution amounted to 70.3% females, 28.4% males, and 1.3%non-binary. Furthermore, a similar gender distribution among all 4 categories (portion of females: C1: 74.6%; C2: 76.0%; C3: 63.9%; C4: 81.7%) was observed.

Nevertheless, distribution within some subgroups of category 4 varied widely, exemplified by respondents reasoning for condom non-use either with their partner's virginity (portion of females: 100%), their homosexual orientation (portion of females: 90.9%) or their usage of other contraceptive agents (portion of females: 93.8%).

Sexual behavior

Looking at the participants' history of sexual activity, students in category 3 showed a significantly lower number of total sex partners compared to category 4 (adjusted compared with-value: 0.0446). In terms of partners with whom sexual intercourse has occurred without a condom, no significant differences were found. Nevertheless, the ratio of sexual contacts without condom use to total contacts was the highest in category 3 (72.9%) followed by all others exceeding 50.0% [Figure 1].{Figure 1}

For further characterization, the total amount of partners with whom sexual intercourse had occurred was analyzed per year of sexual activity diversified by gender.

While no significant correlation was found between female students of all four categories when comparing sex partners per year, in total as well as without condom, males of categories 2 and 4 had significantly more annual contacts in contrast to category 3 (mean contacts per year of sexual activity in total: C1: 0.7; C2: 2.6; C3: 0.8; C4: 2.0; adjusted P values: C2 vs. C3: P = 0.0108; C4 vs. C3: P = 0.0053 [Figure 2]). Moreover, males of both categories had about twice as many condomless contacts per year when compared to those in categories, which exclusively consisted of monogamous participants (mean contacts per year of sexual activity without condom application: C1: 0.3; C2: 0.9; C3: 0.4; C4: 0.6 [Figure 3]).{Figure 2}{Figure 3}

As 4 individuals of category 4 claimed that they did not have sexual intercourse yet, they were excluded from the sexual behavior analysis and thereby did not contribute to observations discussed.

Knowledge about STIs

While all subjects who renounced condom use for oral sex or petting knew that oral sex is a potential source of HPV infection, 60.0% of them were aware that a chlamydia infection can cause infertility. Similarly, the latter statement met approval with 72.7% of students who didn't always use a condom due to homosexual orientation.

All other subgroups, for instance those with a birth control-focused understanding of protection, had at least 87.5% agreeance that chlamydia could potentially cause infertility upon infection.

Although reasons concerning non-use within categories 1–3 was homogeneous, their approval to the proposition, claiming the possibility of an infection with HPV in spite of condom usage, was divided, exemplified with approval rates of 76.2% (C1), 60.0% (C2), and 65.1% (C3). In contrast, the factors previously described met approval of 73.3% among students belonging to category 4 [Figure 4].{Figure 4}


Considering that more than 96.0% of participants were aware that vaginal intercourse can be an HIV transmission route that is potentially infectious for both partners, and that condoms are an adequate preventive measure, our results suggest effectiveness of previous education efforts made by prevention campaigns targeting HIV.

Though protective benefits of condom use against other STIs, for example, gonorrhea or chlamydia, were widely recognized (94.6%), results of condom use behavior in our study cohort largely failed to lived up to the expectations.

While 41.1% always used condoms, all others did so only occasionally, ranging from most of the time to never. Almost a third of participants who did not always use condoms provided “other reasons” for this (33.2%).

At first sight, the majority of students (81.1%) justified their lack of condom use with either explicit monogamous sexual behavior, prior testing, or a combination of both (categories 3-1), that could be suggestive of common risk awareness. However, upon closer inspection, affiliated females showed an indifferent number of sex-partners per year, in total as well as without condom compared with females of category 4, who are considered not monogamous by their implications made. Accordingly, males of category 2 were observed to have the most sexual contacts per year in total as well as without condom application, giving the impression of deceitful interpretation of venereal disease tests.

Moreover, the ratio between sexual contacts without condom use to total contacts exceeded 50.0% within all categories. Considering that a substantial portion, ranging from roughly 23.0% to 40.0%, within respective categories, or 32.6% of all participants, ignored the critical role of smear infections in human papillomavirus transmission. Results might explain, at least in part, tremendous knowledge deficits leading to insufficient risk awareness. Since the composition of our study group was dominated by participants with high educational status, mainly being enrolled in faculties of human/veterinary medicine or pharmaceutical sciences (62.7%), our observations underline the urgent need for improving education and prevention surrounding STIs.

Nevertheless, exclusively focusing on knowledge transfer when conceptualizing prospective prevention campaigns might not suffice in the fight against STI spread in Germany. For example, all students who did not use a condom when practicing oral sex or petting, knew they were potentially at risk of acquiring an HPV infection. Similarly, those who exclusively used other contraceptive methods, were at least 87.5% aware that infertility could be a consequence of chlamydia infection. Furthermore, additional factors, in particular subjective perception and circumstances, e.g., being under influence of drugs or alcohol, were observed to play a role in protective behavior. Although described situations were reflected in varying degrees in gender identity groups, the connected risk is the same for all. Therefore, attempting solution approaches is indispensable when considering that those factors not only arise separately but often interact instead and thereby increase the risks.

Providing education and guidance campaigns, primarily in a digital manner, might appeal to this demographic, since the internet outranked talks (49.3%), friends (33.4%), and family (28.3%) as sources of knowledge in our cohort. On the other hand, our survey again underlined the importance of analogous teaching institutions by ranking second place with an approval rate of 71.4% among all participants surveyed. For this reason alone, a combination of both digital and analogous teaching seems to be the most advantageous. Furthermore, abundance and varying quality and accuracy of online resources may dilute the success of exclusively digital efforts due to lack of professional guidance for source selection. Therefore, empowering close interplay between both digital and analogous strategies might not only complement individual knowledge transfer, but also allow for synergistic effects.

Regarding conception of education campaigns, putting exclusive focus on certain pathogens and STIs should be avoided since results indicated that any underrepresentation in content might lead to a lower risk perception undermining protective behavior. Equal emphasis might serve as a robust foundation enabling students to attain a comprehensive and wide-ranging education on which appropriate and realistic awareness can be based. Furthermore, our study also revealed new topics which could contribute to curriculum development. A reinforced knowledge transfer covering venereal disease tests and more professional guidance when interpreting their significance already exemplifies one option. Moreover, taking greater account of diverse sexual identities and preferences could not only foster common understanding and tolerance but also appears essential in modern society. Accordingly, there is a need for more differentiated presentation of protection measures, including oral dams, warranted by the percent of homosexual participants being almost 91.0% female. In the end, further promotion of vaccination opportunities, at least in terms of HPV, could reduce risk to a certain extent when other protection is not applied owing to non-availability, the influence of alcohol or for whatever reason.

In conclusion, gained insights might benefit the responsible authorities when designing new teaching/awareness concepts by demonstrating obstacles needed to be overcome and providing solution approaches based on observations made on sexual behavior and protective conduct of university students in Germany.

In conclusion, the insights gained from this study could be beneficial when used by the responsible authorities to develop new teaching and awareness campaigns. Through observations on sexual behavior and protective conduct of university students in Germany, our study demonstrated existing barriers that need to be overcome and identified possible approaches to improve directed and appropriate sexual health education for this demographic. Meeting students' needs and creating content that is suitable and effective is crucial for improving the sexual and overall health of the young population in Germany.


We are grateful for the lively exchange and discussion with ohhh foundation.

Contributor ship

Corbinian Fuchs developed and conducted the survey, part wrote the paper and submitted the study.Niklas Teichert part wrote the paper, evaluated the data and assisted in submitting the study.Katharina Neu part wrote the paper.Benjamin Clanner-Engelshofen reviewed the paper.Stefan Zippel part conducted the survey and gave guidance.Lars French gave guidance and helped with the study design.Markus Reinholz gave guidance and helped with the study design.

Key messages

Monogamous students were identified as a yet unnoticed demographic under risk by combining insufficient STI awareness with a history of mainly condomless sexual activity.HPV vaccination appears to be a protective measure worthy of promotion, illustrated by numerous situations when existing STI awareness did not result in condom application.Prospective (German) teaching concepts should put equal emphasis on all STIs, particularly clarified by several tremendous knowledge deficits among students mainly becoming health professionals.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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