The study found women who birthed naturally have an overall risk factor of 0.4% compared to mothers who underwent a ceaserean birth had an overall risk factor of 0.6% of developing Endometriosis
The analysis also showed that the risk of endometriosis increased over time, with 1 additional case of endometriosis occurring for every 325 women who underwent a ceasarean in a 10-year period. However, there was no dose-response effect, meaning that endometriosis was no more likely to develop in women who had 2 or more ceasarean than in women who had just 1 ceasarean.
Andolf E, Thorsell M, Kallen K. Caesarean section and risk for endometriosis: a
prospective cohort study of Swedish registries. BJOG. May 13, 2013. doi:
10.1111/1471-0528.12236. [Epub ahead of print]