On June 24, 2022, the US Supreme Court overturned Roe v Wade in Dobbs v Jackson Women's Health Organization. Therefore, several states banned abortion, and other states are considering more hostile abortion laws. This study aimed to assess the incidence of adverse maternal and neonatal outcomes in the hypothetical cohort where all states have hostile abortion laws compared with the pre-Dobbs v Jackson cohort (supportive abortion laws cohort) and examine the cost-effectiveness of these policies. This study developed a decision and economic analysis model comparing the hostile abortion laws cohort with the supportive abortion laws cohort in a sample of 5.3 million pregnancies. Cost (inflated to 2022 US dollars) estimates were from a healthcare provider's perspective, including immediate and long-term costs. The time horizon was set to a lifetime. Probabilities, costs, and utilities were derived from the literature. The cost-effectiveness threshold was set to be at $100,000 per quality-adjusted life year. Probabilistic sensitivity analyses using the Monte Carlo simulation with 10,000 simulations were performed to assess the robustness of our results. The primary outcomes included maternal mortality and an incremental cost-effectiveness ratio. The secondary outcomes included hysterectomy, cesarean delivery, hospital readmission, neonatal intensive care unit admission, neonatal mortality, profound neurodevelopmental disability, and incremental cost and effectiveness. In the base case analysis, the hostile abortion laws cohort had 12,911 more maternal mortalities, 7518 more hysterectomies, 234,376 more cesarean deliveries, 102,712 more hospital readmissions, 83,911 more neonatal intensive care unit admissions, 3311 more neonatal mortalities, and 904 more cases of profound neurodevelopmental disability than the supportive abortion laws cohort. The hostile abortion laws cohort was associated with more cost ($109.8 billion [hostile abortion laws cohort] vs $75.6 billion [supportive abortion laws cohort]) and 120,749,900 fewer quality-adjusted life years with an incremental cost-effectiveness ratio of negative $140,687.60 than the supportive abortion laws cohort. Probabilistic sensitivity analyses suggested that the chance of the supportive abortion laws cohort being the preferred strategy was more than 95%. When states consider enacting hostile abortion laws, legislators should consider an increase in the incidence of adverse maternal and neonatal outcomes.