Background: Cancer during pregnancy is a rare but increasingly encountered condition due to delayed childbearing and improved survival of women with cancer. The coexistence of malignancy and pregnancy poses complex diagnostic and therapeutic challenges, requiring careful balance between maternal prognosis and fetal safety. Objective: This review aims to summarize current evidence on the diagnosis and multidisciplinary management of cancer during pregnancy, focusing on the safe use of oncologic therapies, obstetric decision-making, and maternal and fetal outcomes. Methods: A narrative review was conducted based on literature identified in PubMed/MEDLINE, Scopus, and Web of Science from January 2000 to September 2025. Search terms included pregnancy-associated cancer, oncologic treatment during pregnancy, obstetric management, and fetal outcomes. Relevant clinical guidelines, registry data, and reference lists were also reviewed. Results: Breast cancer, cervical cancer, melanoma, hematologic malignancies, and gestational trophoblastic neoplasia represent the most frequently reported cancers during pregnancy. Evidence indicates that selected cancer treatments can be administered safely without compromising maternal prognosis. Chemotherapy after the first trimester is generally associated with acceptable fetal outcomes. Physiological changes in pregnancy may delay diagnosis and influence drug pharmacokinetics. Radiotherapy, targeted therapies, and immunotherapies remain limited because of potential fetal toxicity. Avoiding iatrogenic prematurity is a central principle of obstetric management. Conclusions: Cancer during pregnancy should no longer be considered an absolute therapeutic dilemma. With individualized multidisciplinary care, effective maternal treatment and favorable fetal outcomes are increasingly achievable.

The vaginal ecosystem undergoes profound physiological adaptations during pregnancy and the puerperium through dynamic interactions among the vaginal microbiota, epithelial barrier, local immune system, and hormonal milieu. Disruption of this homeostasis may lead to vaginal dysbiosis and infection, with potential consequences for maternal, fetal, and neonatal health. This narrative review aimed to provide a comprehensive and updated overview of the vaginal ecosystem throughout pregnancy and the puerperium, integrating current evidence on physiological changes in the vaginal microbiota, mechanisms of dysbiosis, major vaginal infections, diagnostic approaches, therapeutic management, and maternal–fetal implications. A structured literature search was conducted in PubMed/MEDLINE and Scopus through July 2026. Priority was given to recent systematic reviews, meta-analyses, international clinical guidelines, randomized clinical trials, and observational studies addressing the vaginal microbiota, dysbiosis, bacterial vaginosis, vulvovaginal candidiasis, trichomoniasis, aerobic vaginitis, pregnancy, and the puerperium. Pregnancy is generally characterized by a stable, low-diversity, Lactobacillus-dominated vaginal microbiota, whereas the postpartum period is associated with reduced Lactobacillus abundance, increased microbial diversity, and gradual restoration of eubiosis. Disruption of this ecosystem promotes biofilm formation, microbial persistence, inflammation, and ascending infection. Bacterial vaginosis, vulvovaginal candidiasis, trichomoniasis, and aerobic vaginitis represent the major vaginal infections during pregnancy and the puerperium and have varying associations with adverse outcomes, including preterm birth, preterm premature rupture of membranes, chorioamnionitis, postpartum infection, and neonatal morbidity. Molecular diagnostics and microbiome profiling have improved etiological characterization, while emerging microbiome-directed interventions offer potential strategies for restoring vaginal homeostasis. Current evidence supports an increasingly ecosystem-centered approach to vaginal health during pregnancy and the puerperium. Accurate etiological diagnosis and evidence-based treatment remain essential, while preservation and restoration of vaginal homeostasis may represent important complementary objectives for improving maternal, fetal, and neonatal outcomes.