Outcomes of planned caesarean birth compared with planned or actual vaginal birth: an update and expansion of the NICE Caesarean Birth Guideline systematic review NG192

Background Planned caesarean birth (CB) is an increasingly utilised intervention, observed in almost 1 in 6 first-time mothers giving birth in the UK in 2023-24. Outcomes of planned (or actual) CB have been compared with planned (or actual) vaginal birth (VB) in a UK national guideline, but the scope of the comparison does not fully reflect the range of outcomes of interest to stakeholders. This review provides a comprehensive synthesis of outcomes of planned or actual CB with planned or actual VB to shape information resources which support informed birth planning. Methods The UK NICE Caesarean Birth Guideline NG192 evidence review of outcomes associated with planned CB (or actual CB where no planned CB data was available) was updated and expanded to incorporate additional outcomes prioritised by stakeholders. Results A total of 33 new study reports were combined with 32 reports previously included in NG192. All new reports were observational cohort studies or systematic reviews at low risk of bias. Only 3 studies reported outcomes of planned CB compared with planned VB (regardless of actual mode of birth), whereas all remaining studies reported actual VB outcomes. Planned CB was followed by more maternal infection (wound infection, mastitis, endometritis and urinary tract), venous thrombosis and lower neonatal unit admission rates than a planned VB. In the long-term, CB was linked to one or more sexual problems (insufficient lubrication and dyspareunia) being more common, future pregnancy being less common, and infertility being more frequent than after VB. For offspring, infant urinary tract infection after any CB, gastrointestinal tract infections and autism after planned CB were more common compared with VB. New findings highlight conflicting reports on childhood asthma and type 1 diabetes risk after planned CB, suggesting that prior positive associations may be explained by confounding. Existing evidence in NG192 suggests that cardiac arrest, maternal death and hysterectomy are more common after planned CB, but arise from studies at high risk of bias. NG192 also reports that placenta accreta and uterine rupture in a future pregnancy are more common after any CB. No new evidence was identified on these outcomes. Conclusion This review provides stakeholder-relevant information to populate decision-support materials on outcomes of planned (and actual) CB compared with planned (and actual) VB. The existing evidence base lacks data on long-term outcomes of planned (rather than actual) VB.