Background: The maternal microbiota serve as a key regulator of neonatal immune development and early-life health outcomes. This systematic review aims to find out how the makeup of the maternal microbiota affects newborn immunity and the risk of allergies, identify which microbes are linked to a higher or lower chance of allergies, and assess treatments that could improve newborn immune health. Methods: We conducted a systematic search in PubMed, MEDLINE, and Web of Science, adhering to the PRISMA guidelines. We included randomized controlled trials (RCTs), cohort studies, and observational studies that looked at how the makeup of the maternal microbiota affects newborn immune responses or allergic outcomes in early life. We conducted a systematic search, and the quality of the studies was evaluated using the GRADE system and tools to check for bias (RoB 2, Newcastle–Ottawa Scale, MINORS). Results: We included a total of 74 studies. The main findings showed that having a cesarean delivery and using certain antibiotics during pregnancy increased the risk of allergies, while breastfeeding, taking probiotics, and changing the mother’s diet helped to protect against allergies. Maternal stress had a negative association with the microbiota composition (OR = 1.9–2.4) and neonatal immune regulation. Moreover, the study noted significant geographic variation in the microbiota’s influence, underscoring the importance of contextualized interventions. Conclusions: The composition of the maternal microbiota has a major impact on neonatal immunity and the risk of early-life allergy. Adverse factors include cesarean birth, antibiotic exposure, and maternal stress, all of which have been associated with alterations in neonatal immunity. More studies are required to validate promising microbiota-targeted strategies and develop evidence-based guidelines to improve maternal and neonatal immune health.

Background: Pregnancy induces hormonal, immunologic, and vascular changes that profoundly affect dermatologic health. This systematic review aimed to assess the impact of pregnancy on dermatological disorders in terms of disease incidence, severity, maternal-fetal outcomes, and optimal management strategies. Methods: A systematic search was performed in PubMed, MEDLINE, and Web of Science databases, following PRISMA guidelines. Studies evaluating pregnant women with dermatological disorders, pregnancy-related dermatoses, and pre-existing morbidities, were included. The collaboratively extracted data included patient demographics, disease severity, treatment approaches, and pregnancy outcomes. Results: A total of 8490 pregnant cases with dermatologic changes and conditions caused by pregnancy were studied. The dermatological conditions were divided into physiological changes, pregnancy-related exacerbation of pre-existing skin conditions, and pregnancy-specific dermatoses. Intrahepatic cholestasis of pregnancy and pemphigoid gestationis were associated with increased rates of adverse fetal outcomes in patients with specific dermatoses, including increased preterm birth and fetal distress rates. The atopic eruption of pregnancy and polymorphic eruption of pregnancy were highly relevant, but their effect on fetal health was minimal. The efficacy and safety of treatment modalities, including corticosteroids, antihistamines, and ursodeoxycholic acid, were variable. Conclusions: Pregnancy drastically affects dermatological health, but the nature of the impact depends on the condition. Optimal maternal and fetal outcomes rely on early diagnosis and individualized management strategies. More randomized controlled trials are required to develop standardized diagnostic and treatment guidelines to enhance the quality of dermatologic care during pregnancy.