The risk of placenta accreta following primary elective caesarean delivery: a case–control study
Article first published online: 28 FEB 2013
© 2013 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2013 RCOG
BJOG: An International Journal of Obstetrics & Gynaecology
Volume 120, Issue 7, pages 879–886, June 2013
How to Cite
The risk of placenta accreta following primary elective caesarean delivery: a case–control study. BJOG 2013;120:879–886., , , , .
- Issue published online: 10 MAY 2013
- Article first published online: 28 FEB 2013
- Manuscript Accepted: 7 DEC 2012
- Caesarean section;
- placenta accreta;
- placenta praevia
To evaluate the risk of placenta praevia accreta following primary (first) elective or primary emergency caesarean section in a pregnancy complicated by placenta praevia.
Retrospective matched case–control study, employing variable matching.
Tertiary referral centre between 1993 and 2008.
Sixty-five cases and 102 controls were used for the analysis from a total of 82 667 births during the study period.
Relevant data were abstracted from clinical records. Matching of cases with controls was based on co-existing placenta praevia, number of previous caesarean sections, and age, with one or two controls per case. Results are presented as odds ratios (ORs) with 95% confidence intervals (95% CIs).
Main outcome measures
Placenta accreta in a pregnancy complicated by placenta praevia following a primary elective or emergency caesarean section, and morbidity associated with pregnancies complicated by placenta accreta.
Significantly more cases than controls had an elective caesarean section for their primary caesarean delivery (46.2 versus 18.6%; P < 0.001). There were no differences between groups for previous pregnancy loss, uterine surgery, and vaginal delivery, before or after the primary caesarean section. Compared with primary emergency caesarean section, primary elective caesarean section significantly increased the risk of placenta accreta in a subsequent pregnancy in the presence of placenta praevia (OR 3.00; 95% CI 1.47–6.12; P = 0.025).
Our results suggest that women with a primary elective caesarean section without labour are more likely, compared with those undergoing primary emergency caesarean section with labour, to develop an accreta in a subsequent pregnancy with placenta praevia.