Abstract
BACKGROUND: Surrogacy is considered to be a method that allows infertile couples to have a child with the assistance of a third party, known as the surrogate mother. Two forms exist: traditional surrogacy, in which the surrogate provides the oocyte and is thus genetically related to the newborn, and gestational surrogacy, in which no genetic link is present. Over recent decades, the use of surrogacy has markedly increased, highlighting the need to evaluate its potential benefits and risks. This scoping review aims to summarize maternal, pregnancy, and neonatal outcomes reported in gestational surrogacy studies and to assess how these outcomes vary according to clinical protocols, including oocyte source and embryo transfer type. METHODS: The review considered surrogate mothers and newborns as the population, clinical outcomes as the concept, and surrogacy arrangements as the context. Peer-reviewed studies reporting maternal, pregnancy, or neonatal outcomes were included regardless of design, sample size, or geographical setting. Studies limited to ethical, legal, or psychosocial aspects were excluded. A systematic search was conducted in PubMed, Scopus, and Web of Science. Two reviewers independently screened articles, extracted data, and charted outcomes such as pregnancy and live birth rates, miscarriage rates, and maternal complications. Disagreements were resolved by consensus. RESULTS: From 2,077 articles identified, 19 studies met the inclusion criteria. Pregnancy rate ranged from 24.0% to 61.1%, while live birth rate from 15.8% to 55.5%. No major differences emerged between autologous and donor oocytes, nor between single and double embryo transfer. Miscarriage rates ranged from 3.0% to 17.6%, with minimal variation between fresh and frozen cycles for both autologous (10.5% and 9.8%) and donor oocytes (8.4% and 9.6%), and between fresh and frozen embryos transfers (10.9% and 12.3%). Gestational diabetes ranges from 0% to 27.8%, hypertensive disorder from 0% to 21.2%, and placenta previa from 0% to 4.9%. Preeclampsia showed substantial variability, ranging from 1.2% to 17.1%. CONCLUSION: This scoping review suggests that heterogeneous clinical protocols in gestational surrogacy may adversely affect maternal and neonatal health. Further research- particularly prospective, multicenter studies- is needed to better understand and characterize these outcomes.