Trial of labour after caesarean (TOLAC): analysing predictors and outcome of failure in a multi-ethnic population

Background The global increase in Caesarean section (CS) rate can be reduced by increasing the uptake of trial of labour after caesarean (TOLAC). This study aims to evaluate the success rate and risk factors for failure and the delivery outcome of women who attempted TOLAC in a maternity unit. Materials and Methods This retrospective cohort study was conducted on pregnant women with one previous CS who attempted TOLAC between November 2022 to October 2023 in Al Wakrah Hospital, Qatar. The required data were collected from the women’s electronic records and were analysed. Patients who had successful vaginal delivery were classified as successful TOLAC group and those who attempted TOLAC but had a repeat CS due to obstetric reasons were classified into the failed TOLAC group. The success rate and outcomes of the two groups were determined and univariable and multivariable logistic regression analyses were performed to identify the factors associated with failed TOLAC. Results In total, 341 women with one previous CS who attempted TOLAC had their charts reviewed retrospectively. The overall failure rate was 26.1% (89/341). Five women were diagnosed with scar rupture. All of them had good maternal and neonatal outcomes. None had hysterectomy. The women in the failed TOLAC group had significantly higher incidence of scar rupture and neonatal intensive care unit admissions. The rate of scar dehiscence, major postpartum haemorrhage, infectious morbidity and low Apgar score were also higher in the failed group but not statistically significant. There was no maternal or neonatal death. Multiple regression analysis showed that women of non-Arab ethnicity, no previous vaginal delivery, inter-delivery interval less than 2 years, induction of labour and birth weight > 4000g were risk factors for TOLAC failure Conclusion The study suggested that TOLAC was safe and effective in reducing CS rate in our multi-ethnic population. Failure of TOLAC is associated with increased maternal and neonatal complications and can be predicted. Early identification of failure to progress and fetal distress and prompt intervention will minimize sequelae.