Background/Objectives: Inflammation, infections, and oxidative stress (OS) all have an impact on male infertility, which is a complicated, multifaceted illness. OS affects motility and fertilization capability. It accomplishes this through damaging sperm DNA, oxidizing proteins, and triggering lipid peroxidation. These effects occur due to an imbalance between reactive oxygen species (ROS) and antioxidant defenses. Methods: This review aims to evaluate the impact of oxidative stress and inflammation on male infertility by assessing recent literature. Results: Pro-inflammatory cytokines, like TNF-α and IL-6, interfere with spermatogenesis and promote oxidative damage. Additionally, infections caused by pathogens like Escherichia coli and Chlamydia trachomatis alter the reproductive microenvironment, leading to sperm dysfunction and inflammation. Conclusions: Early detection and targeted treatment are essential due to the intricate interactions among these elements. Microbiota-modulating techniques, antimicrobial therapies, anti-inflammatory drugs, and antioxidants are therapeutic approaches that may help reduce oxidative damage and enhance male fertility.

Male factors may be present in up to 50–70% of infertile couples and the prevalence of male infertility accounts for 20–30% of infertility cases. Understanding the mechanisms and causes behind male infertility remains a challenge, but new diagnostic tools such as DNA fragmentation might aid in cases where the routine semen analysis is insufficient. DNA fragmentation, which refers to damages or breaks of the genetic material of the spermatozoa, is considered one of the main causes of male infertility due to impaired functional capability of sperm. The aim of the present narrative review is to investigate and enlighten the potential correlation between DNA fragmentation and male infertility parameters such as the seminal profile and the reproductive outcomes. Comprehensive research in PubMed/Medline and Scopus databases was conducted and 28 studies were included in the present review. Fourteen studies provided data regarding the impact of DNA fragmentation and seminal parameters and showed a correlation of significantly lower sperm count, lower concentration, motility, and abnormal morphology with an increased DNA fragmentation index (DFI). Similarly, 15 studies provided data regarding the impact of DFI on reproductive outcomes. Two studies showed higher aneuploidy rates with higher DFI values, and seven studies showed significantly lower pregnancy rates and live birth rates with higher DFI values. Ultimately, the studies included in this review highlight, collectively, the importance of measuring sperm DFI in the assessment of male infertility. Further studies are needed to explore the effectiveness of interventions aiming to reduce DFI levels.

The success of in vitro fertilization (IVF) and female reproductive capacity are significantly determined by oocyte quality. Increasing data highlights the significance of oxidative stress—a state of imbalance between reactive oxygen species (ROS) and antioxidant defenses—in regulating oocyte competence. Normal folliculogenesis and ovulation rely on optimal ROS levels; excessive oxidative stress (OS) can lead to DNA fragmentation, undermine meiotic spindle integrity, and trigger apoptosis in cumulus and granulosa cells. Molecular insults impair nuclear and cytoplasmic maturation, thereby impacting fertilization potential and embryonic development. Individuals with polycystic ovarian syndrome (PCOS), endometriosis, advanced maternal age, and metabolic disorders—conditions associated with suboptimal IVF outcomes—frequently exhibit redox imbalance. This narrative review examines significant oxidative markers in the follicular environment, exploring the molecular processes linking OS to diminished oocyte quality and discussing therapy techniques aimed at mitigating oxidative damage. Maintaining redox homeostasis in the ovarian milieu appears to be an effective strategy for enhancing oocyte competence and optimizing outcomes in assisted reproduction.

The functional deterioration of granulosa cells (GCs), essential for follicular growth, steroidogenesis, and oocyte competence, indicates ovarian aging and reduced fertility. An expanding corpus of research indicates that oxidative stress is a primary molecular contributor to granulosa cell dysfunction, culminating in mitochondrial impairment, reduced metabolic support for oocytes, and the activation of regulated apoptotic pathways that end in follicular atresia. Ferroptosis, an emergent type of iron-dependent lipid peroxidation, has been identified as a crucial mechanism contributing to chemotherapy-induced ovarian insufficiency, polycystic ovary syndrome (PCOS), and granulosa cell death in aging ovaries, in addition to conventional apoptosis. The SIRT1-Nrf2 axis acts as a crucial anti-oxidative and anti-ferroptotic system that protects GC viability, maintains mitochondrial homeostasis, and upholds redox equilibrium. SIRT1 promotes mitochondrial biogenesis and metabolic resilience by deacetylating downstream proteins, including FOXO3 and PGC-1α. Nrf2 simultaneously controls the transcriptional activation of detoxifying and antioxidant enzymes, including HO-1, SOD2, NQO1, and GPX4, which are critical inhibitors of ferroptosis. Disruption of SIRT1-Nrf2 signalling accelerates GC senescence, follicular depletion, and reproductive aging. In contrast, pharmaceutical and nutraceutical therapies, including metformin, melatonin, resveratrol, and agents that increase NAD⁺ levels, may reverse ovarian deterioration and reactivate SIRT1-Nrf2 activity. This narrative review highlights innovative treatment prospects for ovarian aging, fertility preservation, and assisted reproduction by synthesising current evidence on ferroptotic pathways, SIRT1-Nrf2 interactions, and oxidative stress in granulosa cells. An understanding of these interrelated biological networks enables the development of tailored therapies that postpone ovarian ageing and enhance reproductive outcomes for women receiving fertility therapy.

Background: Mitochondria are essential for placental function as they regulate energy metabolism, oxidative balance, and apoptotic signaling. Increasing evidence suggests that placental mitochondrial dysfunction may play a role in the development of many poor perinatal outcomes, including preeclampsia, intrauterine growth restriction (IUGR), premature birth, and stillbirth. Nonetheless, no systematic review has thoroughly investigated this connection across human research. This study aims to consolidate evidence from human research concerning the link between placental mitochondrial dysfunction and negative birth outcomes. Methods: A systematic search of PubMed, Scopus, and Web of Science identified human research examining placental mitochondrial features (e.g., mtDNA copy number, ATP production, oxidative stress indicators) in connection with adverse pregnancy outcomes. Methodological variety resulted in narrative data extraction and synthesis. Results: Twenty-nine studies met the inclusion criteria. Mitochondrial dysfunction was consistently associated with PE, IUGR, FGR, and PTB. The most often observed outcomes included diminished mtDNA copy number, decreased ATP production, elevated reactive oxygen species (ROS), and disrupted mitochondrial dynamics, characterized by increased DRP1 and decreased MFN2. Early-onset preeclampsia and symmetric fetal growth restriction exhibited particularly severe mitochondrial abnormalities, indicating a primary placental origin of the condition. Conclusions: A significant factor contributing to adverse pregnancy outcomes is the dysfunction of placental mitochondria. The analogous molecular signatures across many disorders suggest promising avenues for developing targeted therapies aimed at improving maternal–fetal health and predictive biomarkers.