Prenatal Diagnosis Post-Dobbs in an Abortion-Banned State: A Retrospective Cohort Study

After the Supreme Court decision in Dobbs v. Jackson overturned Roe v. Wade, a complete abortion ban went into effect in Tennessee. Abortion restrictions may influence decisions regarding prenatal genetic screening and diagnostic testing; however, the exact impacts are unknown. We aimed to describe any differences in the method, timing, or indications for diagnostic genetic testing between patients presenting to a single regional referral site before and after the Dobbs decision. A retrospective cohort study was performed using pre- (July 2018-March 2019) and post- (July 2022-March 2023) Dobbs comparison groups. The primary outcomes were the changes in rates of chorionic villus sampling (CVS) and amniocentesis between the study groups. All pregnancies that elected diagnostic genetic testing by either CVS or amniocentesis were included. Procedures performed after fetal demise or for indications other than genetic testing were excluded. During the study period, 119 patients underwent diagnostic genetic testing (48 pre-, 71 post-). The changes in rates of CVS and amniocentesis were not significantly different; however, CVS accounted for 16.7% of diagnostic procedures pre-Dobbs compared to 26.8% post-Dobbs. Gestational age at the time of the CVS procedure was statistically lower post-Dobbs (13.1 vs. 11.7 weeks, p = 0.029). Pre-Dobbs, 12.5% of chorionic villus sampling procedures were performed without ultrasound markers or positive screening results, compared to 52.6% post-Dobbs (p = 0.090). CVS accounted for a higher proportion of genetic testing post-Dobbs. Testing occurred at earlier gestational ages and many patients lacked prior abnormal screening results, demonstrating the potential impact of abortion restrictions on this care.