Ovarian hyperstimulation syndrome (OHSS) is the most severe iatrogenic complication of assisted reproductive technology (ART), characterized by capillary leak, third spacing, and associated complications such as hemoconcentration, thromboembolism, and fluid imbalances. Despite preventive strategies, OHSS remains a significant clinical and economic burden. This chapter explores the pivotal role of ultrasound in minimizing morbidity associated with OHSS. Ultrasound is essential for risk assessment, early detection, and management of OHSS, facilitating adjustments in stimulation protocols and guiding therapeutic interventions such as ultrasound-guided paracentesis and thoracentesis. The chapter also discusses the evolving role of Doppler ultrasound in assessing ovarian blood flow and highlights emerging technologies, including three-dimensional imaging and artificial intelligence-assisted monitoring, that may improve patient outcomes. Additionally, the use of point-of-care ultrasound (POCUS) in emergency settings is examined, underscoring its potential to enhance rapid diagnosis and intervention. Future innovations in patient self-monitoring and mobile-integrated ultrasound solutions are anticipated to optimize OHSS management and reduce its associated risks.