Evid Based Nurs 1:85 doi:10.1136/ebn.1.3.85
  • Causation

Review: previous caesarean delivery or abortion increases the risk of placenta praevia

 Question Does a history of caesarean deliveries, spontaneous abortions, or induced abortions increase the risk of placenta praevia?

Data sources

Studies were identified by searching Medline databases using the keywords placenta praevia, placental disorders, antepartum haemorrhage, antepartum bleeding, caesarean delivery, caesarean section, uterine surgery, spontaneous abortion, induced abortion, and elective abortion; and by scanning bibliographies of relevant papers.

Study selection

Studies were selected if they provided quantitative analysis of placenta praevia and were published in English between 1950 and 1996. Studies on placental abruption and case reports were excluded.

Data extraction

Data were extracted on the total number of pregnancies; the number of pregnancies complicated by placenta praevia; previous caesarean deliveries, spontaneous abortions, and induced abortions; study design; and the country in which the study was run. Odds ratios (ORs) were calculated using fixed and random effects models with results from random effects models considered to be more reliable due to evidence of heterogeneity among studies.

Main results

In 36 studies, 13 992 of 3 700 000 women who were pregnant had placenta praevia. The reported incidence was approximately …

Free Sample

This recent issue is free to all users to allow everyone the opportunity to see the full scope and typical content of EBN.
View free sample issue >>

EBN Journal Chat

The EBN Journal Chat offers readers the opportunity to participate in discussion about research articles and commentaries from Evidence Based Nursing (EBN).

How to participate >>

Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.

Navigate This Article