Introduction: The global rise in medical interventions during childbirth, such as caesarean sections, has raised concerns regarding their necessity and impact on maternal and neonatal outcomes. Midwifery-led units (MLUs) have demonstrated lower intervention rates and higher maternal satisfaction.This study evaluates the implementation and effects of the first MLU in the Spanish National Health System. Methods: A retrospective cross-sectional trend study and a cohort study were conducted to compare childbirth interventions and outcomes at XX with other hospitals of varying complexities. Results: The introduction of the MLU at XX resulted in a significant reduction in caesarean sections, decreasing from 23.5% to 13.5%, and an increase in spontaneous vaginal births, rising from 64.2% to 78.7%. These trends reversed following the MLU's closure in 2022, with caesarean sections increasing to 22.9% and spontaneous births dropping to 69.0%. The MLU served 1286 women, with the majority classified as low-risk pregnancies. Obstetric emergencies in the MLU were low and comparable to those in countries with established MLUs. Discussion: This study highlights the potential benefits of integrating MLUs into traditionally medicalized healthcare systems to promote physiological childbirth and reduce unnecessary interventions. The positive outcomes achieved at HM are comparable to those in countries with more established MLU practices, reflecting the unit's commitment to evidence-based care. The increasing interest among women in midwifery-led care indicates a broader demand for supportive, less medicalized childbirth environments. Conclusions: MLU can lead to lower caesarean section rates and higher spontaneous vaginal birth rates, contributing to more positive maternal and neonatal outcomes. However, sustained support and investment in these units are crucial to maintain these benefits. Policymakers and healthcare providers should consider expanding the integration of MLUs within the Spanish National Health System to enhance maternal care quality and align with best practices.

The authors have declared no competing interest.

This study did not receive any funding

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Ethics committee of Fundacio Unio Catalana d'Hospitals gave ethical approval for this work (Code CEI 21/03)

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