Appendectomy across Pregnancy Trimesters: A Systematic Review of Preterm Birth Outcomes

Abstract

Background and Objectives: The possibility of a relationship between appendectomy and preterm birth has been suggested, and the effects of the timing of gestation are not known. This review investigated the relationship between trimester-specific appendectomies with preterm birth and surgical technique and obstetrical outcomes. Methods: The search was conducted in PubMed/MEDLINE and Europe PMC up to 23 October 2026 to identify 366 records. Following the removal of 83 records that were duplicates, 283 were left to be assessed. Clinical data of eight selected studies were analyzed. Published estimates of effects were kept and an exploratory risk ratio was computed. Because of methodological heterogeneity, a meta-analysis could not be performed. Results: Pregnancy outcomes in a Colombian population-based cohort of 2,507 pregnancies that ended in live birth revealed that women who underwent surgery in the third trimester of pregnancy had a higher risk for preterm delivery than women undergoing surgery during a different period of pregnancy (RR 1.65; 95% CI 1.118–2.423). A second group of 50 women had rates of 0%, 13.3%, and 14.3% of preterm births in the three trimesters, respectively. The exploratory third trimester estimate was 1.54 (95% CI 0.20-11.82). The severity of the disease, the way the surgery is performed, and the definition of success made interpretation difficult. Conclusions: Gestational appendectomy at a later stage in the pregnancy may be related to an elevated risk for preterm delivery. The evidence is limited for the trimesters, though, and is confounded, so it is premature to draw clear conclusions about causation. Additional future reporting studies with standardization are needed