Objective This narrative review synthesizes current evidence on free positions delivery during the second stage of labor, evaluating its impact on pelvic floor protection, key clinical outcomes, and maternal experience, while also exploring underlying biomechanical and molecular mechanisms. Methods A comprehensive but non-systematic literature search was conducted in PubMed, Embase, Cochrane Library, and Web of Science from inception to July 2025., using keywords including “free positions delivery,” “upright position,” “second stage of labor,” “pelvic floor dysfunction,” “perineal trauma,” and related terms. Studies were selected based on relevance to maternal position during the second stage and outcomes related to pelvic floor protection, clinical efficiency, and maternal experience. Both observational and interventional studies were included, with priority given to recent systematic reviews, meta-analyses, and high-quality clinical trials. Evidence certainty was narratively assessed using principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Results Free positions are associated with favorable trends in short-term obstetric outcomes, including reduced duration of the second stage and lower rates of perineal trauma. Maternal satisfaction, sense of autonomy, and comfort are consistently improved. For pelvic floor health, the certainty of evidence differs by time horizon: findings suggest a reduction in early postpartum urinary incontinence, but data supporting a long-term protection against pelvic floor dysfunction remain insufficient. Conclusion Current evidence supports consideration of free positions during the second stage of labor as a low-intervention strategy that may improve short-term labor outcomes and maternal experience. Successful implementation requires targeted training for healthcare providers and comprehensive patient education. Future research should prioritize longitudinal studies with standardized outcome measures to strengthen the evidence base for long-term pelvic floor protection.
Yan et al. (Thu,) studied this question.