Background and Objectives: Although considerable research has been devoted to examining the distinctions between fresh and frozen embryo transfer regarding obstetric outcomes and rates of pregnancy success, there is still a scarcity of thorough analyses that specifically examine neonatal outcomes. The objective of our study was to provide an in-depth analysis of neonatal outcomes that occur after the transfer of fresh and frozen embryos (ET vs. FET) in IVF/ICSI cycles. Materials and Methods: Multiple databases (PubMed/MEDLINE, Cochrane Library, Web of Science, Wiley, Scopus, Ovid and Science Direct) were searched from January 1980 to February 2024. Two reviewers conducted the article identification and data extraction, meeting inclusion and exclusion criteria. The methodological quality was evaluated using the Newcastle–Ottawa Scale (NOS) or the revised Cochrane Risk of Bias Tool. The meta-analysis was performed using RevMan 5.4. Results: Twenty studies, including 171,481 participants in total, were subjected to qualitative and quantitative analyses. A significant increase in preterm birth rates was noted with fresh embryo transfer compared to FET in the overall IVF/ICSI population (OR 1.26, 95% CI 1.18–1.35, p < 0.00001), as well as greater odds of a low birth weight (OR 1.37, 95% CI 1.27–1.48, p < 0.00001) and small-for-gestational-age infants in this group (OR 1.81, 95% CI 1.63–2.00, p < 0.00001). In contrast, frozen embryo transfer can result in macrosomic (OR 0.59, 95% CI 0.54–0.65, p < 0.00001) or large-for-gestational-age infants (OR 0.64, 95% CI 0.60–0.69, p < 0.00001). No significant difference was observed regarding congenital malformations or neonatal death rates. Conclusions: This systematic review confirmed that singleton babies conceived by frozen embryo transfer are at lower risk of preterm delivery, low birthweight and being small for gestational age than their counterparts conceived by fresh embryo transfer. The data support embryo cryopreservation but suggest that elective freezing should be limited to cases with a proven indication or within the framework of a clinical study.

Background/Objectives: Pregnancy-associated cancer (PAC) presents significant challenges for maternal and neonatal health, and yet its impact on neonatal outcomes remains poorly understood. This systematic review aims to evaluate the neonatal risks associated with PAC. Methods: A systematic search of PubMed, Embase, Scopus, and other databases was conducted up to 1 November 2024, identifying observational studies and randomized controlled trials assessing neonatal outcomes in pregnancies affected by PAC. Outcomes included preterm birth, low birthweight, macrosomia, small and large for gestational age, low Apgar score, congenital anomalies, and neonatal mortality. Results: Eleven high-quality studies encompassing over 46 million births, including 9953 PAC-affected pregnancies, were reviewed. PAC significantly increased the risks of preterm birth (adjusted ORs ranging from 1.48 to 6.34) and low birthweight (adjusted ORs up to 5.5). Other adverse outcomes included low Apgar scores and neonatal mortality, primarily linked to prematurity. Cancer type and treatment timing influenced these outcomes, with gynecological and breast cancers posing higher risks. Conclusions: Neonates of mothers with PAC face increased risks of adverse outcomes, underscoring the importance of tailored, multidisciplinary management. Further prospective studies are needed to clarify the impacts of specific cancer treatments during pregnancy.

The gut microbiome is a dynamic ecosystem that plays essential roles in host metabolism, immune regulation, colonization resistance, and maintenance of intestinal homeostasis. Antibiotic exposure profoundly disrupts this ecosystem by reducing microbial diversity, depleting beneficial commensals, reshaping microbial metabolic functions, and remodeling the gut resistome through the selection and dissemination of antibiotic resistance genes (ARGs). Increasing evidence from longitudinal metagenomic, multi-omics, and experimental studies indicates that these perturbations may persist long after antibiotic withdrawal due to incomplete ecological recovery, sustained mobile genetic element-mediated ARG dissemination, and altered microbiome resilience. Beyond antimicrobial resistance, antibiotic-induced dysbiosis has been associated with reduced short-chain fatty acid production, altered bile acid metabolism, impaired epithelial barrier function, and broader disturbances in host metabolic homeostasis, although many of these relationships remain associative rather than causal. This review provides an integrated overview of antibiotic-driven gut microbiome dysbiosis, emphasizing the ecological, functional, metabolic, and resistome-level consequences of antibiotic exposure together with the mechanisms governing microbiome recovery. Current microbiome-targeted restoration strategies, including probiotics, phage therapy, fecal microbiota transplantation, and next-generation microbiome therapeutics, are critically evaluated with particular attention to their evidence maturity, limitations, and translational potential. Finally, key knowledge gaps and future research priorities are discussed to support the development of more effective microbiome-preserving antimicrobial strategies and to limit the long-term dissemination of antimicrobial resistance.

Background: Assisted reproductive technology (ART) nowadays plays a major role in the treatment of infertility, with the most frequently used techniques being in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). The objective of this study is to analyze pregnancies achieved using these ART techniques and their correlations with the prematurity and congenital malformations rates. Methods: This is an observational retrospective longitudinal study that includes 814 newborns conceived through an ART, namely IVF or ICSI. Results: Using a multivariate logistic regression analysis mode, there is a higher prematurity rate in twin pregnancies OR 16 (95% CI 10.7, 23.8), donor conception OR 1.8 (95% CI 1.1, 3.3) and PIH pregnancy OR 2.6 (95% CI 1.5, 4.5). The odds of malformations in these ART pregnancies are increased by the stage of the embryo (day 3) OR 2.6 (95% CI 1.3, 5.2), fresh embryo transfer OR 2 (95% CI 1.2, 3.4) and donor conception OR 2.3 (95% CI 1.2, 4.4). The ART used (IVF/ICSI) does not influence the prematurity or birth defects rate. Conclusions: Donor conception is found to increase the odds of both prematurity and congenital malformations. The ART used (IVF/ICSI) does not influence the prematurity or birth defects rate.

This study investigates neonatal outcomes in singleton and multiple pregnancies following in vitro fertilization (IVF) using donor (IVF-D) versus autologous (IVF-A) material. A retrospective cohort analysis was conducted with 988 neonates born between 2017 and 2024 across three tertiary neonatal units in Romania. The primary outcomes included preterm birth, low birthweight, neonatal asphyxia, and congenital malformations. IVF-D pregnancies were associated with a higher prevalence of adverse neonatal outcomes, particularly in multiple gestations. Preterm birth and low birthweight were more frequent in the IVF-D group, with donor-conceived neonates exhibiting increased rates of neonatal ventilation and prolonged hospitalization. Additionally, congenital anomalies, particularly cardiac malformations, were more prevalent in IVF-D pregnancies, suggesting possible immunological and epigenetic influences. Despite these differences, overall neonatal survival was comparable between groups. These findings contribute to the existing literature on assisted reproductive technologies, emphasizing the need for further research to clarify the biological mechanisms influencing neonatal outcomes and to optimize the clinical management of IVF pregnancies using donor gametes.