Reproductive health is strongly influenced by both therapeutic agents and endocrine-disrupting chemicals (EDCs). Chemotherapeutics often impair germ-cell development, while EDCs interfere with hormone-regulated reproductive processes. To assess their impact on gametogenesis, experimental models are essential. In vitro assays such as MTT, comet, and oxidative stress measurements enable precise evaluation of cellular damage and viability in the germ cells, whereas ex vivo testicular and ovarian cultures provide insights into tissue-level effects. On the contrary, in vivo models capture whole-organism outcomes, including fertility endpoints. This chapter highlights the application of these models and assays, the measurable parameters they offer, and their utility in advancing reproductive toxicology and translational research.