Effects of analgesia use during vaginal delivery on the pelvic floor: prospective cohort study

This study aimed to investigate the association between the use of analgesia during vaginal delivery and the prevalence of urinary and anal incontinence complaints up to six months postpartum.

A prospective cohort study was conducted at a maternity hospital, including primiparous women undergoing term vaginal delivery with cephalic presentation and aged over 18 years. Exclusion criteria comprised pre-existing complaints of incontinence. The initial sample calculation estimated that it was necessary to evaluate 50 exposed and 150 unexposed women, although it did not reach the initial sample calculation, the present sample had a power of 84.7 % in rejecting the null hypothesis of this study. Participants were allocated into two groups: Analgesia Group (AG) and Non-Analgesia Group (NAG). Data were collected from March 2022 to August 2023 at three time points: baseline, three months, and six months postpartum. Outcomes were measured using validated instruments: Colorectal Anal Distress Inventory (CRADI-8) and Urinary Distress Inventory (UDI-6) for symptom assessment, and Urinary Impact Questionnaire (UIQ-7) and Colorectal Anal Impact Questionnaire (CRAIQ-7) for quality-of-life evaluation. The study was approved under protocol 5,261,767.

A total of 159 primiparous women were recruited, among whom 63 (39.6 %) were excluded because they had symptoms of incontinence. Ninety-six participants completed the study, with 73 in the NAG and 23 in the AG. The AG showed higher rates of instrumental deliveries, varied fetal head positions including posterior and transverse, severe perineal lacerations, and prolonged first and second stages of labor. At 3 and 6 months postpartum, the incidence of incontinence and its impact on quality of life were similar between groups.

There was no association found between the use of analgesia and the prevalence of incontinence complaints at three and six months postpartum.