National data indicate that women in their 20s and 30s have the highest prevalence of high-risk drinking, representing a substantial public health concern among reproductive-aged women [1]. A previous study examining alcohol consumption among South Korean college students found that 72.9% of female students reported monthly drinking, exceeding the 64.1% observed among women aged 19 to 29 years. In addition, high-risk drinking was reported in 17.2% of female college students, nearly double the corresponding rate of 9.6% among women aged 19 to 29 years [2].

It is widely acknowledged that alcohol consumption can result in adverse fetal developmental outcomes [3]. Even prior to pregnancy, alcohol use among women of reproductive age significantly increases the likelihood of infertility treatment and negatively affects fertility [4,5]. A recent mouse model study further demonstrated that prepregnancy alcohol consumption can induce maternal metabolic dysfunction and increase the risk of fetal developmental abnormalities, birth defects, and macrosomia [6].

Despite these well-documented risks, many female college students demonstrate limited awareness of the dangers associated with alcohol use before conception or during early pregnancy, including fetal alcohol spectrum disorders (FASD) [7,8]. This persistent gap in awareness highlights the urgent need for early, targeted interventions for women of reproductive age.

Women of reproductive age who engage in high-risk drinking should consider reducing alcohol consumption in preparation for future pregnancies. Previous research has demonstrated a significant association between prepregnancy alcohol use, high-risk drinking patterns, and alcohol consumption during pregnancy [9,10]. Moreover, a woman’s current alcohol consumption pattern has been identified as a predictor of her intention to drink alcohol during a future pregnancy [11].

A previous study found that female college students scoring 8 or higher on the Alcohol Use Disorders Identification Test (AUDIT), indicative of high-risk drinking, were less likely to intend to abstain from drinking during pregnancy than peers who did not engage in problem drinking [12]. Accordingly, the present study emphasizes the importance of early intervention to prevent alcohol use during pregnancy and to encourage reductions in alcohol consumption among women exhibiting high-risk drinking behaviors.

The theory of planned behavior (TPB) [13] provides a robust theoretical framework for understanding alcohol-related behaviors [14]. Interventions grounded in TPB have been shown to reduce overall alcohol consumption and binge drinking among newly enrolled university students [15]. Consistent with established guidance for developing TPB-based interventions [16], we examined awareness related to alcohol consumption during pregnancy among female college students using TPB constructs. Attitudes, subjective norms, and drinking frequency have been shown to influence intentions to abstain from alcohol during pregnancy [12].

To enhance the explanatory power of TPB, additional determinants influencing intention or behavior may be incorporated beyond the core constructs [17]. Self-efficacy, defined as an individual’s belief in their ability to perform a specific behavior [18], is conceptually related to, but distinct from, perceived behavioral control (PBC), and has demonstrated a stronger association with intention than PBC [14,19]. Drinking refusal self-efficacy reflects perceived ability to decline alcohol in specific situations and has been associated with lower frequency and quantity of alcohol consumption [20]. Furthermore, drinking refusal self-efficacy mediates the relationship between alcohol outcome expectancies and alcohol consumption [21]. Both drinking refusal self-efficacy and alcohol outcome expectancies significantly explain drinking behaviors among college students [22], and prior interventions have demonstrated improvements in drinking refusal self-efficacy [23]. Within the TPB framework, drinking refusal self-efficacy may be conceptualized as a functional extension or operationalization of PBC in the context of alcohol use. Enhancing self-efficacy thus represents a key mechanism through which interventions may influence intention and subsequent drinking behavior. Accordingly, the intervention effect in this study was examined across multiple factors, including attitudes, subjective norms, intention (TPB components), alcohol outcome expectancies, drinking refusal self-efficacy, and AUDIT scores representing current alcohol consumption.

Therefore, this study aimed to examine the impact of a brief web-based intervention on both current drinking behaviors and future intentions to abstain from alcohol during pregnancy.

The research hypotheses were as follows:

Hypothesis 1. Participants in the intervention group will show a greater decrease in AUDIT scores than those in the control group.

Hypothesis 2. The intervention group will exhibit more negative attitudes toward alcohol consumption during pregnancy than the control group.

Hypothesis 3. The intervention group will report more negative subjective norms related to alcohol use during pregnancy than the control group.

Hypothesis 4. The intervention group will demonstrate a stronger intention to abstain from alcohol during pregnancy than the control group.

Hypothesis 5. The intervention group will report lower positive alcohol outcome expectancies than the control group.

Hypothesis 6. The intervention group will report higher drinking refusal self-efficacy than the control group.

The current study evaluated the efficacy of a web-based brief intervention aimed at reducing alcohol consumption among women of reproductive age. Previous studies have suggested that women in this age group should be evaluated at least annually for patterns of alcohol consumption or risky drinking behaviors [34]. These studies also emphasized the importance of providing appropriate counseling to prevent the adverse effects of alcohol consumption during pregnancy. Importantly, modifying drinking behavior before conception is essential to avoid prenatal alcohol exposure and associated fetal risks [35].

The intervention produced a significant effect on intention to abstain from drinking during pregnancy, consistent with previous research applying the TPB to alcohol use during pregnancy, which identified intention as the strongest determinant of drinking behavior during pregnancy [28]. Accordingly, it is reasonable to anticipate that increased intention to abstain from drinking during pregnancy, fostered by the web-based brief intervention developed in this study, may lead to reduced alcohol consumption in future pregnancies. It should be acknowledged, however, that intentions do not always translate directly into behavior, particularly when the behavior concerns a future life event that may not be imminent. Nevertheless, this study is meaningful in that it increased awareness among female college students—many of whom had not previously considered pregnancy or childbirth—regarding their current drinking behaviors and future reproductive health.

Our findings further indicate that the web-based brief intervention improved attitudes toward drinking during pregnancy and suggested a potential benefit for drinking refusal self-efficacy. These results are consistent with prior studies. For example, an intervention using TPB-based messaging to reduce alcohol consumption among university students resulted in improvements in attitudes, intentions, and self-efficacy [15]. Similarly, a study conducted in England demonstrated that college students exposed to TPB-based messages showed changes in intentions, attitudes, descriptive norms, and self-efficacy related to binge drinking [36].The observed changes in attitudes and intentions in the present study may be explained by the strong association between attitude and intention in women’s drinking behavior, as women are often more influenced by personal perceptions, such as attitudes, than by social norms [14]. Therefore, modifying personal beliefs may be particularly important when designing interventions to influence women’s drinking behavior.

The significant group-by-time interaction effects observed for both attitudes and intentions provide further insight into the intervention’s impact. Compared with the control group, which exhibited minimal change over time, participants in the intervention group demonstrated meaningful improvements from baseline to 4 weeks after the intervention. These findings suggest that the brief web-based program was effective not only in increasing awareness but also in sustaining cognitive and motivational changes over the short term. This pattern of improvement underscores the potential utility of web-based interventions in promoting behavioral change, particularly within the context of preconception health.

Although intention to abstain from drinking during pregnancy increased, AUDIT scores, which reflect current alcohol consumption, did not change significantly following the intervention. Both the intervention and control groups showed decreases in AUDIT scores over time, which may be attributable to government-imposed restrictions on private gatherings during the coronavirus disease-2019 pandemic. Previous reports have indicated that the frequency and volume of alcohol consumption among Korean college students declined during the pandemic, despite an increase in solitary drinking at home [37]. In addition, no significant changes were observed in alcohol outcome expectancies after the intervention. This may be because the outcome expectancies measured reflected general alcohol consumption rather than pregnancy-specific contexts, whereas the intervention emphasized negative birth outcomes as a deterrent to drinking during pregnancy. To obtain more precise insights in future research, the development of a measurement tool for pregnancy-specific alcohol outcome expectancies may be warranted.

The absence of significant intervention effects on subjective norms is consistent with findings from prior review studies examining social norms–based alcohol interventions among college students [38]. However, recent research suggests that exposure to alcohol-related content on social networking services can influence drinking behavior through subjective norms [39]. Accordingly, future research should explore innovative approaches, such as leveraging social media exposure, to more effectively influence subjective norms related to alcohol consumption among college students.

Several limitations of this study should be considered. First, the study assessed only intention to abstain from drinking during pregnancy; therefore, longitudinal research is needed to determine whether the web-based brief intervention leads to sustained changes in actual drinking behavior. Second, as a quasi-experimental study, the absence of random assignment may have introduced selection bias and unmeasured confounding, potentially limiting internal validity. However, baseline comparisons showed no significant differences in general characteristics between the intervention and control groups, suggesting that major confounders were statistically controlled. Another limitation relates to the use of a free downloadable drinking diary application and the Zoom platform for intervention delivery, which restricted the researcher’s ability to monitor participant engagement, track individual progress, or facilitate peer interaction. Although efforts were made to provide guidance and minimize barriers to using these tools, unmeasured biases may have occurred. Future studies should consider developing integrated web-based platforms that enable real-time engagement monitoring and facilitate peer communication. Finally, although self-report measures of drinking behavior are generally reliable and valid when confidentiality is ensured [40], response bias leading to underestimation of alcohol consumption remains possible.

Despite these limitations, the findings of this study have important implications for preconception care and the prevention of FASDs. The results support the need to educate reproductive-aged female college students—particularly those engaging in high-risk drinking—about alcohol prevention as a component of preconception nursing care. Moreover, the observed improvements in psychological constructs such as intention, attitude, and self-efficacy suggest that such interventions may be valuable even before observable behavior change occurs, especially when addressing preventive health behaviors among populations not actively considering pregnancy.

This study also suggests that a single 30-minute web-based brief intervention may serve as a practical tool for healthcare providers. Compared with traditional face-to-face interventions, web-based programs offer advantages including lower implementation costs, broader accessibility regardless of time and location, and enhanced scalability [41]. Given that college students tend to respond favorably to brief interventions with demonstrated effectiveness—whether delivered by counselors or through computer-based personalized feedback—web-based approaches may be particularly suitable for this population [42]. Additionally, the anonymity afforded by web-based platforms may promote more open reflection and engagement, especially when addressing sensitive issues such as alcohol use [43]. Accordingly, this study highlights the feasibility and potential effectiveness of web-based brief interventions as a flexible strategy for promoting preconception health among young women. Although the present study focused on female college students, replication in other populations, such as adolescents or women actively planning pregnancy, could further broaden the applicability of this intervention.

In conclusion, the brief web-based intervention led to significant improvements in attitudes toward drinking during pregnancy, intentions to abstain from drinking during pregnancy, and drinking refusal self-efficacy. Prioritizing the modification of current drinking behaviors is essential, as these behaviors directly affect women’s health and the health of future offspring. Simple, evidence-based interventions may therefore play a critical role in delivering effective preconception nursing care.