Evidence map›Paper›PMID 39445685›Full record

ArticleActa obstetricia et gynecologica Scandinavica2025

Associations between term cesarean delivery in the first pregnancy and second-pregnancy preterm delivery.

Anders Einum, Quaker E Harmon, Linn Marie Sørbye, Roy Miodini Nilsen, Nils-Halvdan Morken

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Article in Acta obstetricia et gynecologica Scandinavica, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

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3citing papers in PubMed
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1 · What the graph read from it

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3 · Its place in the literature

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3 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Anders EinumDepartment of Clinical Science, University of Bergen, Bergen, Norway.ORCID 0000-0002-2972-4868
Quaker E HarmonNational Institute of Environmental Health Sciences, Durham, North Carolina, USA.
Linn Marie SørbyeDepartment of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.
Roy Miodini NilsenFaculty of Health and Social Sciences, Western Norway University of Applied Sciences, Bergen, Norway.
Nils-Halvdan MorkenDepartment of Clinical Science, University of Bergen, Bergen, Norway.

Funding

Gidske and Peter Jacob Sørensens FundHelse Vest F-12156/4800003677NIEHS NIH HHS Z01ES103333Odd Fellow Medical Fund
6 · The paper itself

Abstract

introductionCesarean delivery has been shown to increase the risk of preterm delivery in future pregnancies. The association could be a direct result of the procedure, or because the indications that led to the cesarean delivery also increase the risk of preterm delivery in later pregnancies. MATERIAL AND

methods298 901 mothers with first and second singleton deliveries from 1999 to 2020 were investigated using data from the Medical Birth Registry of Norway linked with Statistics Norway. The mothers were categorized by mode of cesarean delivery (total, emergency and planned) and vaginal delivery at term in the first pregnancy. We used log-binomial regression models to estimate relative risks with 95% confidence intervals (CI) of iatrogenic and spontaneous preterm delivery <37 gestational weeks in the second pregnancy. Second, we explored the role of recurrent placental disease in preterm delivery by comparing estimates in mothers with placental disease in neither or both pregnancies.

results8243 mothers (2.8%) had a preterm delivery in the second pregnancy. The adjusted relative risk (aRR) of preterm delivery was 1.24 (95% CI 1.17-1.32) after cesarean compared with vaginal delivery in the first pregnancy. The association was stronger in previous planned compared with emergency cesarean delivery (aRR 1.52, 95% CI 1.30-1.77 and aRR 1.21, 95% CI 1.14-1.29, respectively). Spontaneous preterm delivery was not associated with the previous mode of delivery; the risk was confined to iatrogenic preterm delivery after both emergency and planned cesarean delivery (aRR 1.69, 95% CI 1.52-1.87 and aRR 2.65, 95% CI 2.12-3.30, respectively). Mothers with placental disease in both pregnancies had a sixfold increased risk of preterm delivery in the second pregnancy compared with mothers with no placental disease, however, the association between mode of delivery and subsequent preterm delivery was similar in mothers with and without placental disease in the pregnancies.

conclusionsCompared with vaginal term delivery in the first pregnancy, cesarean delivery increases the risk of iatrogenic, but not spontaneous preterm delivery in the next pregnancy. Although strongly associated with preterm delivery, placental disease had limited influence on the estimates.

Indexed as

Cesarean SectionPremature BirthAdultFemaleHumansInfant, NewbornNorwayPregnancyRegistriesRisk Factorsemergency cesarean deliveryfetal growth restrictiongestational ageiatrogenic deliveryplacentaplanned cesarean deliverypreeclampsiapreterm birthspontaneous delivery

Identifiers

PMID39445685
PMCPMC11683550

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