Episiotomies and obstetric anal sphincter injuries following a restrictive episiotomy policy in France: An analysis of the 2010, 2016, and 2021 National Perinatal Surveys.

BACKGROUND

The French guidelines have recommended a restrictive policy of episiotomy since 2005. We aimed to assess variations in the prevalence of both episiotomy and obstetric anal sphincter injury (OASI) from the 2010, 2016, and 2021 National Perinatal Surveys.

METHODS AND FINDINGS

A total of 29,750 women who had given birth to a live infant by vaginal delivery were included. For instance, in 2021, 22.3% of women were over 35 years old, 17.7% were born outside of France, 11.3% had a body mass index (BMI) of 30 kg/m2 or higher, and 39.9% were primiparous. Episiotomy and OASI (third- and fourth-degree tears) were identified from medical records. We described the overall prevalence of outcomes, and then by obstetrical clinical contexts using a seven-group obstetric classification of women. Variations between 2010 (reference), 2016, and 2021 were analyzed by Cochran-Armitage tests and using Poisson regression models adjusted for maternal age, BMI, country of birth, antenatal classes, suspicion of fetal macrosomia, and neuroaxial analgesia during labor, the professional who attended the birth, the annual number of deliveries, and the maternity unit status to account for changes in women's characteristics and obstetric practices. The overall prevalence of episiotomy decreased significantly from 25.8% (95% confidence interval (CI) 25.0 to 26.7) in 2010, to 20.1% (95% CI 19.3 to 20.9) in 2016, and 8.3% (95% CI 7.8 to 8.9) in 2021 (adjusted risk ratio (aRR) 0.33, 95% CI 0.30 to 0.35). This reduction was observed in all groups of the classification (Cochran-Armitage tests P < 0.001), ranging from -33.0% in Group 2a [nulliparous term cephalic singleton with forceps delivery] to -94.0% in Group 7 [multiple pregnancy]. The difference in overall prevalence of OASI between 2010 (0.7%) and 2021 (1.0%) was not statistically significant after adjustment (aRR 1.24, 95% CI 0.91 to 1.68). By groups of classification, the prevalence of OASI increased significantly only in Group 2b [nulliparous term cephalic singleton with spatula delivery] from 2.6% (95% CI 1.2 to 5.6) in 2010 to 9.6% (95% CI 6.2 to 14.7) in 2021 (aRR 3.69, 95% CI 1.50 to 9.09), and did not differ statistically significantly in Group 2a [nulliparous term cephalic singleton with forceps delivery] from 3.2% (95% CI 1.8 to 5.7) in 2010 to 5.7% (95% CI 3.4 to 9.5) in 2021 (aRR 1.78, 95% CI 0.81 to 3.90). The main limitations of this study include the failure to take into account some potential confounding factors and the inability to analyze some groups of the studied population (8.5% of the sample) because of the very small number of events in these groups.

CONCLUSIONS

The significant overall reduction in the prevalence of episiotomy in France has not been followed by an overall increase in OASI. However, subgroup analyses revealed a significant rise in OASI among nulliparous women giving birth by spatula (Group 2b), and a clinically relevant but statistically nonsignificant rise among nulliparous women delivering by forceps (Group 2a), while the prevalence of episiotomy significantly decreased. These results should be interpreted with caution given the low prevalence of OASI in some subgroups. Further research is needed to predict the optimal rate of episiotomy for instrumental deliveries. In hospitals with high episiotomy rates, our findings suggest that episiotomy could be safely reduced for spontaneous vaginal deliveries to comply with international guidelines and women's requests.