Cesarean Surgical Morbidity Risk

Evidence-based prevalence data and risk factor assessment for severe perioperative surgical complications in patients undergoing cesarean delivery

1.7%

Overall severe perioperative surgical morbidity

594,655

Cesarean deliveries studied (CA, 2016–2021)

15×

Increased risk with placenta accreta spectrum

PUBLICATIONS USED IN THIS TOOL

1

Retrospective Cohort

Butwick A, Baer RJ, Farooqi N, Stephansson O, Jelliffe-Pawlowski L. Severe perioperative surgical morbidity with cesarean delivery. Obstet Gynecol. 2025;00:1–10. doi:10.1097/AOG.0000000000006041

Primary source: prevalence rates, risk factors, adjusted risk ratios for all morbidity categories. California live births 2016–2021, n=594,655 singleton cesarean deliveries.

About This Tool

This tool displays published prevalence rates for severe perioperative surgical morbidity (SPSM) following cesarean delivery, and identifies patient-level risk factors from the Butwick et al. 2025 retrospective cohort study. SPSM was defined as any composite of: intra-abdominal/pelvic visceral or vascular injury, hysterectomy, pelvic/retroperitoneal hematoma, wound complications, ileus/bowel obstruction, acute peritonitis, or shock.

Delivery Type

Select the type of cesarean delivery — this determines the baseline morbidity rate

Cesarean Delivery Type

Prelabor (Elective) No labor prior to CD; scheduled or elective

Intrapartum (Emergency) Labor, induction, fetal distress, arrest of labor

Gestational Age at Delivery

<28 wks aRR 2.16 (1.83–2.55)

28–31 wks aRR 1.89 (1.66–2.14)

32–36 wks aRR 1.50 (1.41–1.59)

37–40 wks Reference group

>40 wks aRR 1.17 (1.08–1.27)

Patient Risk Factors

Select all that apply — adjusted risk ratios from Butwick et al. 2025

Maternal Age

<20 yearsaRR 0.85 (0.69–1.05)

20–24 yearsReference group

25–29 yearsaRR 1.21 (1.11–1.33)

30–34 yearsaRR 1.44 (1.32–1.57)

≥35 yearsaRR 1.76 (1.61–1.92)

Race / Ethnicity

Adjusted RRs vs. Non-Hispanic White (reference) · Butwick et al. 2025. Associations with CI crossing 1.0 are shown for transparency but carry an aRR of 1.00 in the calculation.

Non-Hispanic WhiteReference group

Non-Hispanic BlackaRR 1.13 (1.04–1.24) — significant

HispanicaRR 0.93 (0.88–0.98) — significant

Non-Hispanic AsianaRR 1.07 (1.00–1.14) — borderline

NH American Indian / Alaska NativeaRR 0.97 (0.70–1.35) — not significant

NH Native Hawaiian / Pacific IslanderaRR 1.05 (0.78–1.42) — not significant

Other / Not reportedaRR 1.12 (1.02–1.22) — significant

Prior Cesarean Deliveries

NoneReference group

1 prior CDaRR 1.22 (1.16–1.28)

≥2 prior CDsaRR 1.58 (1.49–1.68)

Placental Conditions

NoneReference group

Placenta PreviaaRR 1.45 (1.33–1.58)

PAS DisorderaRR 15.3 (14.0–16.7) — 44% affected

Additional Risk Factors

Comorbidities and intrapartum conditions

Insurance Type

PrivateReference group

Public (Medicaid)aRR 1.09 (1.04–1.15) — significant

OtheraRR 0.92 (0.85–1.00) — borderline

Highest Educational Level

<12 yearsaRR 1.09 (1.01–1.17) — significant

12 years (HS diploma)Reference group

>12 yearsaRR 1.01 (0.95–1.07) — not significant

Pre-pregnancy BMI

Note: obesity (BMI ≥30) is associated with lower SPSM risk vs. normal weight in this dataset — likely reflecting greater surgical experience at higher-volume centers with obese patients, or unmeasured confounding.

Underweight (<18.5)aRR 1.15 (1.01–1.30) — significant

Normal (18.5–29.9)Reference group

Obesity Class I (30–34.9)aRR 0.87 (0.82–0.92) — significant

Obesity Class II (35–39.9)aRR 0.86 (0.80–0.93) — significant

Obesity Class III (≥40)aRR 0.88 (0.80–0.95) — significant

Comorbidities

Hypertensive DisorderGestational HTN / Preeclampsia / Eclampsia · aRR 1.31 (1.24–1.38)

Chronic HypertensionaRR 1.19 (1.08–1.33)

Intrapartum Conditions

ChorioamnionitisaRR 1.95 (1.82–2.10)

Hospital Setting

Teaching Status

Teaching HospitalaRR 1.39 (1.33–1.45)

Non-Teaching HospitalReference group

Location

UrbanaRR 0.84 (0.75–0.94) — significant

RuralReference group

Annual Cesarean Volume

Low (0–216/yr)aRR 0.92 (0.84–1.01)

Mid (217–605/yr)aRR 1.23 (1.18–1.28)

High (>605/yr)Reference group

Risk Profile Summary

Based on published data from Butwick et al. Obstet Gynecol 2025

Complication Prevalence by Category (All Cesarean Deliveries)

Per 10,000 cesarean deliveries · Butwick et al. 2025 · n=594,655

Complication	All CD (/10,000)	Prelabor (/10,000)	Intrapartum (/10,000)
SPSM (composite)	171 (168–175)	146 (142–150)	203 (198–209)
Wound complication / infection	59 (57–61)	51 (49–54)	68 (65–71)
Bladder / GU / pelvic injury	45 (43–47)	39 (37–41)	52 (50–55)
Ileus or bowel obstruction	33 (32–35)	25 (23–27)	44 (42–47)
Shock	15 (14–16)	9 (8–11)	22 (20–24)
Bowel injury (intraoperative)	14 (13–15)	12 (11–13)	17 (15–18)
Hysterectomy	13 (13–15)	13 (12–14)	16 (14–17)
Pelvic / retroperitoneal hematoma	9 (8–10)	8 (7–9)	10 (9–12)
Vascular injury	2.5 (2.1–2.9)	1.3 (0.9–1.7)	4.0 (3.3–4.8)

Complication	Prevalence (/10,000)	95% CI
Shock	403	323–492
Bladder / GU / pelvic injury	278	212–353
Wound complication / infection	181	128–242

Key Risk Factors — Adjusted Risk Ratios (All Cesarean Deliveries)

Multivariable Poisson log-linear regression · Butwick et al. 2025

Risk Factor	Adjusted RR	95% CI
PAS disorder	15.3	14.0–16.7
Chorioamnionitis	1.95	1.82–2.10
Labor / induction of labor	1.70	1.62–1.77
Age ≥35 vs. 20–24 y	1.76	1.61–1.92
≥2 prior cesarean deliveries	1.58	1.49–1.68
Teaching hospital	1.39	1.33–1.45
Hypertensive disorder of pregnancy	1.31	1.24–1.38
1 prior cesarean delivery	1.22	1.16–1.28
Chronic hypertension	1.19	1.08–1.33
Placenta previa	1.45	1.33–1.58
GA <28 weeks	2.16	1.83–2.55
Middle-volume hospital (217–605/yr)	1.23	1.18–1.28