Vocalization for the Second Stage of Labor (VOCAL)

A randomized open-label trial will be conducted to evaluate the effect of vocalization as a perineal protection maneuver during the second period of labor. The study will be carried out in the "Espaço Aconchego" sector of the IMIP, which has a team of obstetrical nurses, medical coordination and physiotherapeutic support. The study population will consist of low-risk parturients, with no prior cesarean indication, admitted to the sector. Those parturients who meet the inclusion criteria, after signing the Informed Consent Term, will be allocated to two groups: Group A (experimental) and Group B (control). Group A will be stimulated to keep the glottis minimally open during spontaneous pushing and to emit sounds when exhaling (vocalization), and Group B will undergo usual routine. Study outcomes will be evaluated by assistents immediately after delivery. After 24 hours of delivery, the conditions of the perineum will be assessed by inspection and palpation of the region,evaluating the presence of edema or other abnormality.