This chapter provides an in-depth exploration of advanced strategies to predict and prevent ovarian hyperstimulation syndrome (OHSS), a severe complication of assisted reproductive technologies (ART). It highlights the significance of anti-Müllerian hormone (AMH) and antral follicle count (AFC) as key markers for assessing OHSS risk. By tailoring ovarian stimulation protocols based on these markers, clinicians can significantly reduce the incidence of OHSS. The chapter discusses various preventive measures, including the use of GnRH antagonists, GnRH agonist triggers, and adjunctive therapies such as metformin and cabergoline. These strategies have been shown to modulate ovarian response and reduce vascular permeability, thereby lowering OHSS risk. Recent case studies demonstrate the effectiveness of individualized controlled ovarian stimulation (iCOS) protocols, which adjust gonadotropin doses based on ovarian reserve markers, in preventing OHSS. Emerging therapies, such as vasopressin V1a receptor antagonists, are discussed as potential future interventions for OHSS prevention. Through a comprehensive review of current research and clinical practices, this chapter underscores the transformative potential of integrating ovarian markers into routine clinical practice. By adopting these evidence-based strategies, fertility specialists can enhance the safety and efficacy of ART, ensuring better outcomes for patients. This chapter serves as a crucial resource for clinicians and researchers dedicated to advancing reproductive health and improving the management of OHSS.