From gametogenesis and fertilization to embryonic development and a healthy birth, reproductive biology is essential to population dynamics, individual health, and societal wellbeing. Disruptions in reproductive function, whether brought on by genetic factors, environmental exposures, or clinical interventions like assisted reproductive technologies, have significant personal and societal repercussions. This review explores the role of epigenetics in reproductive biology with emphasis on epigenetic marks and their impact on fertility. Findings have revealed that fertility also supports demographic trends, shapes public health planning, and affects socioeconomic outcomes. DNA methylation, post-translational histone modifications, chromatin remodeling, and noncoding RNA-mediated regulation are examples of biochemical markers and molecular mechanisms that affect gene expression without changing the underlying DNA sequence. Collectively, these markers determine chromatin accessibility and the transcriptional programs that define cell identity and function. During gametogenesis, germ cells undergo substantial reprogramming, and the early embryo undergoes genome-wide waves of demethylation and de novo methylation that create lineage-specific epigenomes. These processes make epigenetics particularly dynamic and crucial in reproductive situations. Because these periods align with the manipulation of gametes and the culture of embryos in assisted reproduction, changes to epigenetic programming can have a significant impact on imprinting, developmental paths, and long-term health. Changes in epigenetic markers have been connected in the last 20 years to a variety of reproductive diseases and fertility problems. Environmental factors such as stress, air pollution, endocrine-disrupting chemicals, and maternal nutrition can alter gamete quality, embryo viability, and placental function. In certain situations, these alterations may have an impact on future generations. Concerns regarding imprinting disorders and subtle epigenetic changes seen in some offspring conceived through in vitro fertilization and related procedures demonstrate the clinical relevance of these mechanisms, which drives both more in-depth mechanistic research and improvements to ART protocols to reduce epigenetic risk. Hence, epigenetic insights offer new avenues for diagnosis and intervention. Epigenomic profiling can identify biomarkers of gamete competence and endometrial receptivity, and targeted modulation of epigenetic regulators holds potential for restoring normal reproductive function in selected settings.