Objective <p>Consanguineous marriages increase the incidence of rare genetic diseases within society. During pregnancy, screening and diagnostic tests are performed for certain diseases. These tests detect the risk of anomalies in the fetus and enable the necessary diagnostic tests to be performed to diagnose the fetus in utero. This study aimed to compare the decision conflict levels regarding prenatal screening tests experienced by pregnant women who had consanguineous marriages and those who did not.</p> Methods <p>This descriptive, cross-sectional, comparative study included 346 pregnant women who applied to the obstetrics and gynecology outpatient clinic of an educational research hospital in Mardin, Turkiye. The Demographic Characteristics Form and Decisional Conflict Scale (DCS) were used as data collection tools in the study.</p> Results <p>The mean age of the pregnant women participating in the study was 28.08 ± 4.61 years, and the mean gestational age was 20.13 ± 5.55 weeks. We found no statistically significant difference between the total DCS scores of pregnant women and their consanguineous marriage status (<i>t</i> = −2.586, <i>p</i> = 0.674). There was a statistically significant difference between pregnant women who had consanguineous marriages and those who did not in terms of the presence of genetic diseases in their family (χ² = 22.936, <i>p</i> &lt; 0.001) and having a child with a genetic disease (χ² = 5.549, <i>p</i> = 0.018).</p> Conclusions <p>The consanguineous marriage status of the pregnant women did not affect their decisional conflict. The educational levels of pregnant individuals affected their decisional conflict levels in both groups. Pregnant women who had a family history of a genetic disease or a child affected with a genetic disorder had higher decisional conflict levels. It is important to find innovative ways to decrease pregnant women’s decisional conflict and increase their use of prenatal testing for individuals who have consanguineous marriages.</p>