Nuclear emergencies can generate ionizing radiation that potentially induces severe, irreversible gonadal injury and theoretically heritable genetic risks among exposed emergency responders. Because germ cells and gonadal tissues are highly radiosensitive, reproductive organs are susceptible to radiation-mediated harm. Clinically observed radiation-associated reproductive outcomes cover impaired spermatogenesis in males, progressive ovarian follicle loss in females, and temporary or permanent infertility. It should be noted that authoritative assessments by the International Commission on Radiological Protection and the United Nations Scientific Committee on the Effects of Atomic Radiation indicate minimal population-level heritable disease risks under routine low-dose nuclear emergency exposure. Physical shielding tools and radioprotective pharmaceuticals serve as core countermeasures to lower gonadal absorbed dose and preserve responders' fertility, yet their field applicability differs substantially from clinical radiotherapy settings. This narrative review systematically elaborates on radiation-induced reproductive hazards specific to nuclear accident conditions, categorizes mainstream gonadal shielding hardware and radioprotective agents alongside their technical performances, and highlights prominent research gaps as well as targeted developmental suggestions. The summarized evidence provides evidence-based references for formulating standardized radiation protection and fertility conservation protocols for frontline nuclear emergency personnel.