Although historically prenatal genetic screening has relied on ultrasound and maternal serum analyses, recent years have seen a 15% annualized growth rate of the fetal cell-free DNA (cfDNA) test since its introduction in 2011. Despite the high accuracy of these screens, sensitive information within their results regarding current and future health for both the pregnant patient and the fetus renders the leftover samples as valuable for research and development. However, the sensitive data do not always belong to patients, as commercial laboratories performing the analyses sometimes maintain rights to use, retain, and even share these data. Some companies do give granular control of data to patients, but the overarching theme of these companies includes opaque or nonexistent privacy policies. The aim of this study was to investigate the baseline knowledge of pregnant patients about the use of their prenatal genetic data for nonclinical purposes in a randomized controlled trial (RCT), as well as to investigate whether video-based education would affect patients' willingness to share data to benefit research. The hypothesis of the authors was that unique privacy concerns would exist among pregnancy patients, especially regarding the sharing, use, and retention of genetic information regarding themselves and their fetuses. They further hypothesized that activity on social media and demographic factors would be associated with willingness to share genetic information for nonclinical purposes. This double-blind RCT took place at the Prenatal Diagnosis Center at Women and Infants Hospital (a tertiary maternity hospital in Providence, Rhode Island) and included the following eligibility criteria: younger than or equal to 18 years, singleton pregnancy, and underwent cfDNA during the current pregnancy and later presented for a detailed anatomy scan between the gestational weeks of 17(0/7) and 23(6/7). In addition, participants were required to speak English because this was the only language of the video intervention. Exclusion criteria were as follows: previous study participation, unscheduled or urgent anatomical scans, and suboptimally dated pregnancies. Eligible patients were screened and approached before their detailed anatomical ultrasound, with consenting patients being randomized 1:1 in either the intervention or control group. The control group participants viewed a 2-page infographic about cfDNA jointly developed by the Society for Maternal-Fetal Medicine, the American College of Obstetricians and Gynecologists, and the National Society of Genetic Counselors. However, the infographic did not address genetic privacy. Intervention group participants viewed the same infographic and an additional video regarding the Genetic Information Nondiscrimination Act (GINA). They then completed a 42-item questionnaire on a tablet regarding demographic information and knowledge/attitudes of prenatal genetic screening and genetic privacy. These responses were sent directly to a secure Research Electronic Data Capture database, along with timestamps for each procedural step of the trial. Primary outcomes of the study included knowledge of commercial laboratories' abilities to share prenatal genetic data in nonclinical research scenarios, along with willingness for these laboratories to share data to the following 3 groups: academic researchers, government-funded medical research databases, and companies that might profit from the provided genetic information. Secondary outcomes included general genetic privacy law knowledge, knowledge regarding potential to reidentify anonymized genetic data, and willingness to share or retain maternal and/or fetal genetic information. A total of 160 qualifying participants were recruited, with 80 assigned to each group. The cohort was diverse, with 25% identifying as non-White and 20% as Hispanic. The groups were similar with regard to age, gestational age, education level, insurance type, and risk of aneuploidy. The groups demonstrated similar baseline knowledge of cfDNA testing, and in 95%, they indicated that early detection of Down syndrome was somewhat or very important, and in 50%, early determination of fetal sex was somewhat or very important. Participants in the intervention group (with the video) were more likely to incorrectly respond that laboratories were not allowed to share genetic data for research and other nonclinical purposes (28.8% vs 46.2%; P = 0.03). Between the 2 groups, there was no variation regarding patient willingness to share fetal genetic information for research purposes. However, women who self-identified as non-White were much less willing to share these data for research purposes. Because companies retain and use prenatal genetic data obtained via cfDNA screening, patients considering this procedure ought to be counseled about genetic privacy implications before undergoing the screening or testing. This is especially important as cfDNA genetic screenings cannot identify all actionable conditions, and some parents opt for the screenings simply for early identification of fetal sex. One clinical implication of this study is that pregnant patients' understanding of and preferences regarding personal/fetal genetic information sharing do not often align with policies of commercial laboratories. This indicates a likelihood that patients are undergoing cfDNA aneuploidy screening without providing truly informed consent surrounding this test's genetic privacy implications. The attempt of the study to educate patients about these privacy implications resulted in unintended attitudes about and knowledge of genetic privacy issues. Further research is imperative for the understanding of pregnant patients' interpretation of privacy rights of their genetic material and information. Overall, participants were unaware of the potential for their prenatal genetic data to be used for nonclinical purposes. The video education did not alter willingness to share genetic data, but it did falsely lead patients to believe their genetic data would not or could not be shared for research. Further research to discover effective evidence-based interventions and educational resources on these topics are necessary for the improvement of pregnant patients' genetic privacy understanding.