Am J Perinatol 2020; 37(06): 633-637
DOI: 10.1055/s-0039-1685449
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Effect of Trial of Labor before Cesarean and Risk of Subsequent Placenta Accreta Spectrum Disorders

Katharine N. O'Malley
1  Department of Obstetrics and Gynecology, Kaiser Permanente Northern California, Santa Clara Medical Center, Santa Clara, California
Mary E. Norton
2  Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, San Francisco, California
Sarah S. Osmundson
3  Department of Obstetrics and Gynecology, Vanderbilt University, Nashville, Tennessee
› Author Affiliations
Further Information

Publication History

20 October 2018

28 February 2019

Publication Date:
16 April 2019 (online)


Objective This study aimed to examine whether labor before cesarean affects the risk of placenta accreta spectrum (PAS) disorders in a subsequent pregnancy.

Study Design This is a secondary analysis of the Cesarean Registry, a prospective cohort study of women undergoing cesarean between 1999 and 2002. Women with one prior cesarean with known indications, which were categorized as likely associated with labor (labored cesarean) versus likely not associated with labor (unlabored cesarean), were included. Primary outcome was PAS disorder.

Results Of 34,224 women, 60% had a “labored cesarean” and 40% had an “unlabored cesarean.” Women with prior unlabored cesarean were more likely to have subsequent PAS disorder compared with women with a prior labored cesarean after adjusting for confounders (0.28 vs. 0.13%; adjusted odds ratio: 2.03; 95% confidence interval: 1.22–3.38).

Conclusion Prior unlabored cesarean is associated with an increased risk of PAS disorders in a subsequent pregnancy. This association may aid in risk stratification in women with suspected PAS disorders and help counsel about risks associated with cesarean on maternal request.