To investigate Vietnamese undergraduate students’ knowledge and attitudes towards contraception and their associated factors.

Cross-sectional study.

Six universities in Vietnam from April to May 2025.

1134 undergraduate students.

Students’ knowledge and attitudes towards contraception were measured via an online survey, and a cut-off point of 50% was used to categorise their scores. Associations between students’ knowledge and attitude scores and their sociodemographic characteristics, academic background, sexual and relationship experiences, contraceptive education and information sources were evaluated using multivariable linear regression. Independent variables were selected through Bayesian Model Averaging.

Students’ average knowledge and attitude scores were 10.93±2.86 (possible range: 0–22; actual range: 0–19) and 54.14±6.57 (possible range: 15–75; actual range: 35–74), respectively. 62.1% demonstrated good knowledge, and 91.4% showed positive attitudes towards contraception. Higher knowledge was observed among older students (per 1 year increase, β=0.33, 95% CI 0.23 to 0.43), those from public universities (β=1.32, 95% CI 0.64 to 2.00), using mass media as a contraceptive information source (β=0.58, 95% CI 0.25 to 0.91) and having sexual experience (β=1.16, 95% CI 0.73 to 1.58). By contrast, students who were single and had never been in a romantic relationship (β=–0.88, 95% CI –1.23 to –0.52) and those enrolled in non-healthcare disciplines (β=–1.06, 95% CI –1.55 to –0.56) had significantly lower knowledge scores. Positive attitudes were more prevalent among female students (males vs females: β=–2.07, 95% CI –2.80 to –1.34), those using the Internet as a source of contraceptive information (β=5.65, 95% CI 4.29 to 7.01) and those with higher knowledge scores (per one-unit increase, β=0.67, 95% CI 0.55 to 0.79). All associations were statistically significant (p

In general, undergraduate students’ knowledge of contraception was relatively low, while their attitudes were positive. Implementing education programmes focusing on correct usage and storage of condoms and the safety of emergency contraceptive pills may help improve their understanding and promote safer sexual practices, thereby contributing to reducing the risk of sexually transmitted infections and unintended pregnancies.