Rebozo and advanced maternal postures: A promising set of intrapartum interventions to reduce persistent occiput posterior position of the fetal head.

Introduction: Spinning Babies® procedures and the Rebozo technique have been recently implemented as additional interventions in laboring women with a fetus in occiput posterior position (OPP) to favor the rotation to an anterior position, which improve birth experience and health outcomes. Our study aimed to compare the probability of occurrence of persistent OPP (POPP) of the fetal head at the second stage of labor between retrospective and prospective cohorts and to assess associated sociodemographic, obstetric and intrapartum factors.

Methods: We conducted a combined prospective and retrospective cohort study including 1500 women giving birth in 2017 (retrospective cohort) and 779 between 15 May and 15 December 2023 (prospective cohort). Each cohort was divided into two sub-cohorts depending on presence of OPP. Primary outcomes were compared the probability of occurrence of POPP in the two OPP sub-cohorts by a log binomial regression and logistic regression. A p<0.05 was considered statistically significant. Data analysis was performed using Stata/MP18.0.

Results: The proportion of OPP at the onset of labor was similar between the two cohorts (34.9% vs 35.1%). The probability of occurrence of POPP was significantly lower in the prospective OPP sub-cohort (27.7%, n=65/235) compared to the retrospective OPP sub-cohort (35.8%, n=154/430) (risk difference, RD= -0.081; 95% CI: -0.15 - -0.008; p=0.031). In the retrospective OPP sub-cohort, maternal age ≥35 years (RD=0.096; 95% CI: 0.001-0.190, p=0.044) and nulliparity (RD= -0.100; 95% CI: -0.190 - -0.001, p=0.036) were significantly associated with the probability of POPP.

Conclusions: Our findings suggest a potential benefit of a set of interventions combining Spinning Babies® and the Rebozo technique in decreasing the probability of POPP.