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Researchers from the UK and the School of Women’s and Infants’ Health at the University of Western Australia have conducted a large literature review, published in PLoS Medicine, which identified one randomised controlled trial and 79 cohort studies (29 928 274 participants overall) that assessed long term outcomes after caesarean delivery and vaginal delivery. Compared with vaginal deliveries, caesarean deliveries were found to be associated with a decreased risk of urinary incontinence (1024/7306 caesarean delivery v 7713/51 594 vaginal delivery; odds ratio [OR], 0.56; 95% confidence interval [CI], 0.47–0.66) and pelvic prolapse (116/4898 caesarean delivery v 2055/34 310 vaginal delivery; OR, 0.29; 95% CI, 0.17–0.51). Children born by caesarean delivery had an increased risk of asthma for up to 12 years (4788/124 668 caesarean delivery v 23 308/763 292 vaginal delivery; OR, 1.21; 95% CI, 1.11–1.32) and of obesity up to 5 years of age (834/6645 caesarean delivery v 5295/57 468 vaginal delivery; OR, 1.59; 95% CI, 1.33–1.90). Pregnancy after caesarean delivery was associated with an increased risk of miscarriage (2060/19 106 previous caesarean delivery v 12 663/132 306 previous vaginal delivery; OR, 1.17; 95% CI, 1.03–1.32), stillbirth (496/118 192 previous caesarean delivery v 1905/585 370 previous vaginal delivery; OR, 1.27; 95% CI, 1.15–1.40), placenta praevia (5039/1 025 692 previous caesarean delivery v 16 679/6 076 000 previous vaginal delivery; OR, 1.74; 95% CI, 1.62–1.87), placenta accreta (44/66 241 previous caesarean delivery v 188/638 867 previous vaginal delivery), and placental abruption (6047/858 208 previous caesarean delivery v 23 855/4 808 952 previous vaginal delivery; OR, 1.38; 95% CI, 1.27–1.49). Because the findings were predominantly based on observational data, causation cannot be inferred and the findings should be interpreted with caution. Further, the authors were not able to analyse the data by planned (elective) or emergency caesarean delivery.