INTRODUCTION: Sexuality went from being a taboo to a matter of human rights regarding intimacy, sexual and reproductive disputes. Maternity in university students may produce a greater effort in the academic commitment, as well as limiting the time and quality of the academic activities. However, when pregnancy occurs, it is only the woman who carries its risk, “single mom” burden and child care in most cases. OBJECTIVES: To determine the number of marital union and the factors of exposure to pregnancy risk in university students of exact sciences programs in a public university of Cartagena. METHODS: A quantitative research, of a descriptive type, with a population composed of students enrolled in 3 professional programs of Exact and Natural Sciences of a public university in Cartagena, Colombia, was carried out. A two-stage sampling was done. An Outline of the social and demographic profile of the participants for research purpose was prepared. Natality and exposure to pregnancy risk questions were applied. Data was processed using Epi lnfo 7.0, quantitative analysis was made using central tendency measures and qualitative variables and categories that applied to the study. RESULTS: 26% of the 89 participating students were women and were on average of 20 years old with a SD of 2.23. 63% belonged to the subsidized system of the Colombian Health System. 97% of the participants belonged to socioeconomic levels 1 and 2. 94% of the participants declared heterosexual behavior. Regarding the number of people with whom they have had sexual intercourse throughout their lives, the range of one to two people was 28%, while 18% answered that they have had coital encounters with three or more people. 16% of the participants said they felt pressured by some friends to start their sexual relations. 56% of the surveyed reported having vaginal sex, of which 47% have performed this practice without the use of a condom. In the same way, 19% practiced anal sex, where 9% of them did not use condoms. CONCLUSION: It is necessary to develop initiatives in the academic context that embraces the guidelines developed by WHO and UNFPA regarding sexual life and sexuality.