This study aimed to examine the association between regular physical activity (PA) during pregnancy and the incidence of episiotomy and perineal trauma (1st–4th degree). The following hypotheses were proposed:
H1 – Lower incidence of episiotomy among physically active pregnant women,
H2 – Lower incidence of 3rd–4th degree perineal trauma,
H3 – Higher incidence of 1st–2nd degree perineal trauma, due to reduced rates of routine episiotomy.

We conducted the first retrospective cohort study of its kind on a population level, using data from the National Perinatal Information System (NPIS) collected between 2019 and 2022. The study included singleton vaginal deliveries without pathological obesity (BMI ≥35), chronic disease, or multiple gestation. Regular physical activity was defined as engaging in physical exercise at least twice per week, as self-reported during prenatal visits.
Primary outcomes included the incidence of episiotomy, 1st–2nd degree perineal trauma, and 3rd–4th degree trauma. Logistic regression models were applied and adjusted for maternal age, pre-pregnancy BMI, and comorbidities. Statistical significance was assessed using chi-square tests, odds ratios (OR), and 95% confidence intervals (CI). Ethical considerations followed national legislation on the use of anonymized health data, and no ethics committee approval was required.

A total of 89,231 vaginal births were analyzed; 75.1% of women reported regular physical activity.
•	Episiotomy was performed in 28.8% of births. It was significantly less frequent among active women (28.0%) compared to inactive women (31.1%) (χ²(1) = 62.959; p < 0.001; OR = 0.860; 95% CI: 0.828–0.892).
•	1st–2nd degree perineal trauma occurred in 28.1% of cases overall. The incidence was higher among active women (29.0%) versus inactive women (25.6%) (χ²(1) = 71.525; p < 0.001; OR = 1.183; 95% CI: 1.138–1.230).
•	3rd–4th degree trauma was reported in 1.0% of births. No significant association with physical activity was found (active: 0.9%, inactive: 1.0%) (χ²(1) = 0.075; p = 0.784; OR = 0.976; 95% CI: 0.818–1.163).

Regular physical activity during pregnancy was associated with a statistically significant reduction in the incidence of episiotomy. In addition, it may enhance muscular flexibility and tissue elasticity of the pelvic floor, potentially contributing to more favorable birth outcomes [1]. The slightly higher rate of 1st–2nd degree perineal tears observed among physically active women may reflect a greater occurrence of spontaneous vaginal deliveries without the use of surgical perineal interventions. Importantly, physical activity was not associated with an increased risk of obstetric anal sphincter injury (OASIS).
These findings are consistent with previous research indicating that regular physical activity and PFMT during pregnancy reduce the risk of severe perineal trauma and urinary incontinence, although they may not significantly impact episiotomy rates [2]. Routine episiotomy has been shown to contribute to increased perineal dysfunction without providing benefits in continence or sexual function [3].

This population-based study confirms that regular physical activity during pregnancy significantly reduces the likelihood of episiotomy without increasing the risk of severe perineal trauma. While 1st–2nd degree tears may occur more frequently, they are less invasive than episiotomies and typically heal without complications or lasting impact on quality of life. Incorporating physical activity counseling into routine prenatal care may enhance maternal outcomes and aligns with contemporary clinical guidelines.

1.	Feria-Ramírez, C., Gonzalez-Sanz, J. D., Molina-Luque, R., & Molina-Recio, G. (2021). The effects of the Pilates method on pelvic floor injuries during pregnancy and childbirth: A quasi-experimental study. Int J Environ Res Public Health, 18(13), 6995. https://doi.org/10.3390/ijerph18136995
2.	Zhang, D., Bø, K., Montejo, R., Sánchez-Polán, M., Silva-José, C., Palacio, M., & Barakat, R. (2023). Influence of pelvic floor muscle training during pregnancy on urinary incontinence, episiotomy, and perineal tear: Systematic review and meta-analysis. Acta Obstet Gynecol Scand, 103(6), 1015–1027. https://doi.org/10.1111/aogs.14744
3.	Hartmann, K., Viswanathan, M., Palmieri, R., Gartlehner, G., Thorp, J., & Lohr, K. N. (2005). Outcomes of routine episiotomy: A systematic review. JAMA, 293(17), 2141–2148. https://doi.org/10.1001/jama.293.17.2141