Am J Perinatol
DOI: 10.1055/a-2099-3912
Original Article

Risk Factors for Adverse Maternal Outcomes among Patients with Severe Preeclampsia Before 34 Weeks

1   Duke University, School of Medicine, Durham, North Carolina
Jacquelyn L. Dillon
1   Duke University, School of Medicine, Durham, North Carolina
Alice Darling
2   Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
Sabrena Myers
1   Duke University, School of Medicine, Durham, North Carolina
Noor Al Shibli
2   Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
2   Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
Annie West-Honart
2   Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
2   Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
3   Department of Obstetrics and Gynecology, Vanderbilt University, Nashville, Tennessee
Sarah K. Dotters-Katz
2   Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
› Author Affiliations
Funding None.


Objective This study aimed to characterize rates of maternal morbidity associated with early (<34 wk) preeclampsia with severe features and to determine factors associated with developing these morbidities.

Study Design Retrospective cohort study of patients with early preeclampsia with severe features at a single institution from 2013 to 2019. Inclusion criteria were admission between 23 and 34 weeks and diagnosis of preeclampsia with severe features. Maternal morbidity defined as death, sepsis, intensive care unit (ICU) admission, acute renal insufficiency (acute kidney injury [AKI]), postpartum (PP) dilation and curettage, PP hysterectomy, venous thromboembolism (VTE), PP hemorrhage (PPH), PP wound infection, PP endometritis, pelvic abscess, PP pneumonia, readmission, and/or need for blood transfusion. Death, ICU admission, VTE, AKI, PP hysterectomy, sepsis, and/or transfusion of >2 units were considered severe maternal morbidity (SMM). Simple statistics used to compare characteristics among patients experiencing any morbidity and those not. Poisson regression used to assess relative risks.

Results Of 260 patients included, 77 (29.6%) experienced maternal morbidity and 16 (6.2%) experienced severe morbidity. PPH (n = 46, 17.7%) was the most common morbidity, although 15 (5.8%) patients were readmitted, 16 (6.2%) needed a blood transfusion, and 14 (5.4%) had AKI. Patients who experienced maternal morbidity were more likely to be advanced maternal age, have preexisting diabetes, have multiples, and deliver nonvaginally (all ps < 0.05). Diagnosis of preeclampsia < 28 weeks or longer latency from diagnosis to delivery were not associated with increased maternal morbidity. In regression models, the relative risk of maternal morbidity remained significant for twins (adjusted odds ration [aOR]: 2.57; 95% confidence interval [CI]: 1.67, 3.96) and preexisting diabetes (aOR: 1.64; 95% CI: 1.04, 2.58), whereas attempted vaginal delivery was protective (aOR: 0.53; 95% CI: 0.30, 0.92).

Conclusion In this cohort, more than 1 in 4 patients diagnosed with early preeclampsia with severe features experienced maternal morbidity, whereas 1 in 16 patients experienced SMM. Twins and pregestational diabetes were associated with higher risk of morbidity, whereas attempted vaginal delivery was protective. These data may be helpful in promoting risk reduction and counseling patients diagnosed with early preeclampsia with severe features.

Key Points

  • One in four patients diagnosed with preeclampsia w/ severe features experienced maternal morbidity.

  • One in 16 patients with preeclampsia w/ severe features experienced severe maternal morbidity.

  • Factors most associated with morbidity/severe morbidity were twins and pregestational diabetes.

  • Patients who attempted vaginal delivery appeared to have a lower rate of morbidity.


This work was presented as a poster at the 42nd Annual Maternal Meeting for the Society of Maternal Fetal Medicine as a poster presentation on February 3, 2022.

Publication History

Received: 31 August 2022

Accepted: 22 May 2023

Accepted Manuscript online:
24 May 2023

Article published online:
28 June 2023

© 2023. Thieme. All rights reserved.

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