Prenatal Genetic Testing on TikTok: Lay Narratives and Expertise.

In recent years, social-media platforms have seen a rise in content related to pregnancy "gender reveals," wherein parents-to-be draw from the results of NIPT (noninvasive prenatal testing) to disclose the "gender" of their fetus. Such reveals are grounded in inaccurate understandings of NIPT as a technology and its relationship to fetal sex or gender information, understandings that can perpetuate harms for parents-to-be and infants alike. To explore where these understandings come from and how they are communicated, this study offers a thematic, narrative analysis of 40 recent TikTok videos posted by lay individuals discussing both NIPT and fetal sex chromosomes, sex, and/or gender. Findings reveal that almost all videos upheld both a diagnostic myth about NIPT (that the test is diagnostic rather than a probabilistic screening) and a conflation myth (wherein sex and gender are considered equivalent concepts). Videos fell into one of three narrative themes (i.e., personal storytelling; educational framing; co-storytelling), which were made persuasive by specific configurations of lay expertise (i.e., experiential; hybrid; relational, respectively). These results extend predominant theories of lay expertise by identifying and operationalizing distinct forms of lay expertise at work in the context of health communication on social media.