Caesarean section and risk for endometriosis: a prospective cohort study of Swedish registries

E Andolf, Ellika Andolf, Malin Thorsell, M Thorsell, Karin Källén, K Källén
BJOG: An International Journal of Obstetrics & Gynaecology · 2013 · vol. 120(9) , pp. 1061–1065 · doi:10.1111/1471-0528.12236 · PMID:23663181 · W2013113228
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This study found that women who had a caesarean section had a 1.8-fold increased hazard ratio for endometriosis compared to women with only vaginal deliveries.

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Abstract

OBJECTIVE: To investigate the association between caesarean section and later endometriosis. DESIGN: A prospective cohort study. SETTING: The Swedish Patient Register (PAR) and the Swedish Medical Birth Registry (MBR). SAMPLE: Women who were delivered in Sweden between 1986 and 2004. METHODS: Women with the diagnosis of endometriosis, defined as codes 617 (International Classification of Diseases, ninth revision, ICD-9) or N80 (ICD-10), were retrieved from the PAR. Obstetric outcome was assessed through linkage with the MBR. Out of 709,090 women, 3110 were treated as inpatients with a first diagnosis of endometriosis after their first delivery. Women with a diagnosis of endometriosis before their first delivery were excluded. Cox analyses were performed to obtain hazard ratios for endometriosis and adjusted for maternal age at first delivery, body mass index, maternal smoking, and years of involuntary childlessness at study entry. Kaplan-Meier estimates were performed to calculate the risk according to time elapsed. MAIN OUTCOME: In-hospital diagnosis of endometriosis. RESULTS: The Cox analyses yielded a hazard ratio of 1.8 (95% CI 1.7-1.9) for endometriosis in women who had had a previous caesarean section compared with women with vaginal deliveries only. The risk of endometriosis increased over time: one additional case of endometriosis was found for every 325 women undergoing caesarean section within 10 years. No increase in risk could be seen after two caesarean deliveries. The risk of caesarean scar endometrioma was 0.1%. CONCLUSION: In addition to the recognised risk of scar endometrioma, we found an association between caesarean section and general pelvic endometriosis. Further studies are needed to confirm our findings.

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Condition tags

mesh:D004715endometriosisendometrioma

MeSH descriptors

Cesarean Section Cicatrix Endometriosis Adult Cesarean Section Cesarean Section Cicatrix Cicatrix Cicatrix Cohort Studies Delivery, Obstetric Endometriosis Endometriosis Female Follow-Up Studies Humans Maternal Age Parity Pregnancy Prospective Studies

Citation neighborhood

Papers in the corpus that this work cites (lower rings, blue) and that cite this one (upper rings, green). Dot size scales with the paper's in-corpus citation count — bigger dot = more influential within the endo/adeno field. Click a dot to open that paper. [ expand to 2 hops ] — adds papers reached through this work's immediate citers/citees. Heavier; up to 60 extra dots.

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Cited by (32)

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