Impact of previous caesarean section on outcomes of first and second trimester surgical abortion: A systematic review and meta-analysis

BACKGROUND: It is unclear whether previous caesarean section (CS) increases the risk of complications during surgical abortion. AIMS: To compare surgical abortion complication rates in women with a history of previous CS to those without previous CS. MATERIALS AND METHODS: Four databases were systematically searched in July 2024. Primary studies in English reporting on surgical abortion complications in women with and without a history of previous CS were included. Overall complications and major complications were compared between women with and without previous CS using a random effects meta-analysis. Sub-analyses were performed in women with > 1 previous CS, and incidence of emergency hysterectomy. Certainty of evidence was assessed using GRADE. RESULTS: Ten retrospective cohort studies with 3123 women with and 14,514 without a previous CS were included in the meta-analysis. The overall incidence of major complications from surgical abortion was 0.9 %. Previous CS was associated with an increase in overall complications (OR = 2.00, CI 1.32-3.04, p = 0.001) and major complications (OR = 2.82, CI 1.83-4.36, p < 0.00001). Major complications included haemorrhage requiring transfusion, uterine perforation and unplanned laparoscopy/laparotomy, while minor complications included cervical laceration and the need for repeat evacuation. There were no cases of uterine rupture during pre-procedural cervical ripening. Hysterectomy was an exceptionally rare occurrence (0.05 %); low-quality evidence from seven studies showed an association between history of CS and need for emergency hysterectomy (OR = 8.73, CI = 1.83-41.61, p = 0.007). The quality of the evidence was judged to be very low to medium mainly due to risk of bias of the included studies. CONCLUSION: While major surgical complications of surgical abortion are rare, women with a prior history of CS were more than twice as likely to experience a complication.