This narrative review explores contemporary therapeutic options and critically assesses surgical results and in vitro fertilization-intracytoplasmic sperm injection (IVF/ICSI) outcomes in women affected by endometriosis, deep infiltrating endometriosis (DIE) and/or adenomyosis. A literature search was conducted in PubMed for English-language publications up to September 2025. Out of 350 screened articles, 91 studies fulfilling the inclusion criteria were ultimately included in the analysis. Endometriosis and adenomyosis are important causes of infertility and frequently coexist. Deep infiltrating endometriosis (DIE) represents a severe form and is often associated with adenomyosis. Endometriosis is linked to reduced oocyte yield and embryo quality, whereas live birth rates (LBR) are generally comparable to other infertility etiologies. IVF/ICSI outcomes in adenomyosis remain controversial, although most studies and meta-analysis report negative effects, particularly in diffuse adenomyosis involving the junctional zone (JZ), enlarged uterus, and severe disease. Evidence regarding gonadotropin-releasing hormone (GnRH) analogue treatment and fresh vs. frozen embryo transfer (FET) cycles is inconsistent; FET appears beneficial in endometriosis but shows similar outcomes to fresh cycles in adenomyosis. When both conditions coexist, adenomyosis has a greater adverse impact on miscarriage and LBR. Cumulative LBR better reflects ART outcomes in these patients. Non-surgical treatments show promise in adenomyosis, and in asymptomatic DIE, first-line IVF/ICSI is reasonable. Both conditions increase pregnancy complications; therefore, pre-ART screening with ultrasonography (US) and magnetic resonance imaging (MRI) using standardized criteria is recommended.