Investigating knowledge, attitude, and practice regarding the health risks of consanguineous marriages in Saudi Arabia: a cross-sectional study

<p><strong>Objective:</strong> This study aimed to study knowledge, attitude, and practice regarding the health risks of consanguineous marriage (CM) among the population in the Western region of Saudi Arabia.<br /><strong>Methods:</strong> A cross-sectional study was conducted among a total of 1,789 adults aged 18 years and above,<br />residing in the Western region of Saudi Arabia, from June to July 2025, using a snowball sampling technique.<br />An online questionnaire was designed based on a literature review.<br /><strong>Results:</strong> The participants were predominantly females (70.3%), aged 21-30 years (42.3%), and university educated (58.0%), with 20.4% working in medical professions. Of the 762 who responded to the consanguinity<br />question, 33.2% reported being in a CM, mostly with the first cousin (25.2%). Overall mean knowledge score<br />was 73.4% ± 26.4%, with 80.8% scoring above 50%; mean attitude score was 70.1% ± 9.1, with 98.4% scoring<br />above 50%. Knowledge gaps were identified in awareness of premarital screening components (26.4% correct) and availability of premarital whole exome sequencing (51.6% correct). Female gender, younger age (18-20 years), university or high school education, and healthcare employment were independently associated with higher knowledge scores (p < 0.05). Attitudes were uniformly positive toward genetic screening but varied toward CM. In practice, 60% reported avoiding CM if screening results were incompatible.<br /><strong>Conclusion:</strong> While general knowledge and attitudes toward genetic screening were favorable, substantial<br />educational gaps persisted, particularly regarding available testing and residual genetic risk. This highlighted<br />the need for targeted public health education and campaigns for older, less-educated, and non-healthcare<br />populations.</p>