Objectives: To describe the clinical profile and outcomes of pregnant women with COVID-19–related ARDS who underwent prone positioning in a tertiary referral center.

Design: Retrospective observational study.

Setting: Tertiary university hospital in southern Brazil.

Patients: Pregnant women ≥18 years admitted to the ICU with confirmed COVID-19 and managed with prone positioning (2020–2021).

Measurements and Main Results: Seven patients were included. Mean age was 27.4 ± 3.8 years, mean gestational age 29.1 ± 3.8 weeks, mean BMI 33.1 ± 4.6 kg/m², and mean SAPS III 52.7 ± 10.1. Three (42.9%) had diabetes, two (28.6%) hypertension, and one (14.3%) was a smoker. Six (87.5%) required vasopressors, and one (14.3%) received inhaled nitric oxide. Proning sessions ranged from 1 to 7. Four patients (57.1%) developed stage 1–2 pressure injuries, all of which resolved. No major adverse events (accidental extubation, ocular injury, or brachial plexus injury) were reported. Three patients (42.9%) died. All neonates were delivered alive.

Conclusions: Prone positioning was feasible and did not result in major maternal complications in pregnant women with COVID-19–related ARDS, including in the second and third trimesters. Larger studies are needed to confirm maternal and fetal safety.

• Acute Respiratory Distress Syndrome; COVID-19; Pregnancy; Prone Positioning.

Moretti MMS, Dalfert JM, Candaten AE, Welter D, Scheffer KD, et al. (2025) Prone Positioning in Pregnant Patients with COVID-19–Related ARDS: A Case Series. Arch Emerg Med Crit Care 9(2): 1072.

Acute respiratory distress syndrome (ARDS) is a severe complication of COVID-19, with mortality rates approaching 40% despite optimized intensive care [1]. Prone positioning is one of the few interventions shown to reduce mortality in ARDS by improving oxygenation and ventilation–perfusion matching [2-4]. Pregnancy was initially not recognized as a high-risk condition for COVID-19, but subsequent data demonstrated higher rates of ICU admission, mechanical ventilation, ECMO use, preterm delivery, and maternal mortality compared with non-pregnant women [5-8]. Physiological adaptations of pregnancy-including reduced functional residual capacity, increased oxygen consumption, and decreased tolerance to hypoxemia—further increase vulnerability to respiratory failure [9,10]. Historically, prone positioning was considered contraindicated in pregnancy, particularly in the second and third trimesters, due to concerns about uterine compression and impaired uteroplacental blood flow [11,12]. During the COVID-19 pandemic, however, proning was used as a rescue strategy in critically ill pregnant women [13-15]. This study aimed to describe the clinical characteristics and outcomes of pregnant patients with COVID-19–related ARDS managed with prone positioning.

This retrospective observational study was conducted in a tertiary public university hospital in southern Brazil. We included all pregnant women ≥18 years with confirmed COVID-19 admitted to the ICU and treated with prone positioning between 2020 and 2021. Patients with incomplete medical records were excluded. Data collected included demographics, comorbidities, gestational age, severity scores (SAPS III), ventilatory support, use of vasopressors and adjunctive therapies, number of proning sessions, and complications. Outcomes assessed were ICU length of stay, duration of mechanical ventilation, and hospital mortality.Data were extracted from electronic medical records using a structured instrument. Continuous variables were expressed as mean ± SD or median (interquartile range), and categorical variables as absolute numbers and percentages. This study was approved by the institutional research ethics committee (CAAE 56740921800005327).

Seven patients were included. Mean age was 27.4 ± 3.8 years, mean gestational age 29.1 ± 3.8 weeks, mean BMI 33.1 ± 4.6 kg/m², and mean SAPS III 52.7 ± 10.1. Three patients (42.9%) had diabetes, two (28.6%) hypertension, and one (14.3%) was a smoker. Six patients (87.5%) required vasopressors; one (14.3%) received inhaled nitric oxide. No patient underwent renal replacement therapy or ECMO. The number of proning sessions ranged from 1 to 7 (two patients one session, one patient three sessions, two patients four sessions, one patient six sessions, one patient seven sessions). Four patients (57.1%) developed pressure injuries (stage 1–2), which resolved within 7 days. No accidental extubations, corneal injuries, or brachial plexus injuries were observed. Three patients (42.9%) died, including one in the second trimester and two in the third. All neonates were delivered alive, but neonatal outcomes were not tracked.

This series demonstrates that prone positioning is feasible in pregnant patients with COVID-19–related ARDS, even in later trimesters. Historically considered contraindicated, pregnancy is now regarded as a relative contraindication, with proning recommended when clinically indicated and performed with appropriate precautions [11-13]. No major maternal complications occurred in this cohort, supporting the safety of the intervention when conducted by experienced teams with structured checklists [15]. Mild pressure injuries were common, consistent with risk factors such as elevated BMI, vasopressor use, and critical illness [16]. Mortality remained high (42.9%), likely reflecting disease severity rather than the intervention itself [17,18]. These findings align with emerging evidence suggesting that prone positioning can be an effective rescue therapy in pregnant women with severe ARDS [6,7,13]. Limitations include the small sample size, retrospective design, and lack of neonatal follow-up.

Prone positioning was feasible and did not result in major complications in pregnant women with COVID-19 related ARDS, including those in the second and third trimesters. This strategy should be considered in selected patients when hypoxemia is refractory to conventional measures. Larger prospective studies are needed to confirm maternal and fetal safety.

1. World Health Organization. Oxygen sources and distribution for COVID-19 treatment centres: interim guidance. Geneva, Switzerland: World Health Organization; 2020.
2. Rocha FEV, Oliveira JF, Pereira VS. The use of the prone position in patients diagnosed with COVID-19: a systematic review. FisiSenectus. 2020; 8: 133-142.
3. Galhardo FPL, Martinez JAB. Síndrome do desconforto respiratório agudo. Medicina (Ribeirão Preto). 2003; 36: 248-256.
4. Guérin C, Reignier J, Richard JC. PROSEVA Study Group. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med. 2013; 368: 2159-2168.
5. Borges DL, Rapello GVG, Deponti GN, Andrade FMD. Posição prona no tratamento da insuficiência respiratória aguda na COVID-19. ASSOBRAFIR Ciência. 2020; 11: 111.
6. Cavalcante FML, Fernandes CS, Rocha LS, Galindo-Neto NM, Caetano JA, Barros LM. Use of the prone position in pregnant women with COVID-19 or other health conditions. Rev Lat Am Enfermagem. 2021; 29: e3494.
7. Peres GP, Ferraz JG, Matos AFM, Zöllner MSA. Epidemiological profile of pregnant women infected with COVID-19. Braz J Infect Dis. 2022; 26: 102587.
8. Amorim MMR, Souza ASR, Melo ASO, Delgado AM, Florêncio ACMCC, Oliveira TV, et al. COVID-19 and pregnancy. Rev Bras Saude Mater Infant. 2021; 21: 337-353.
9. Sociedade Brasileira de Pneumologia e Tisiologia; Associação de Medicina Intensiva Brasileira. Diretrizes 2013.
10. Amato MBP, Carvalho CRR, Vieira S, Isola A, Rotman V, Moock M, et al. Ventilação mecânica na lesão pulmonar aguda/síndrome do desconforto respiratório agudo. Rev Bras Ter Intensiva. 2007; 19: 374-383.
11. Oliveira VM, Piekala DM, Deponti GN. Safe prone checklist: construction and implementation of a tool for performing the prone maneuver. Rev Bras Ter Intensiva. 2017; 29: 131-141.
12. Borges DL, Rapello GVG, Andrade FMD. Posição prona no tratamento da insuficiência respiratória aguda na COVID-19. ASSOBRAFIR Ciência. 2020; 11: 111.
13. Vandse R, Cook M, Bergese S. Perioperative management of a pregnant polytrauma patient for spine fixation surgery. F1000Res. 2015; 4: 171.
14. Speirs E, Wiles M, Bacon A, Radley S. Positioning a proned patient with cauda equina syndrome who presents at 15 weeks gestation: a case report. F1000Res. 2014; 3: 117.
15. Welter DI, Batista DCR, Moretti MMS, Piekala DM, Oliveira VM. Clinical profile and complications in proned patients: a cohort from a university hospital. Clin Biomed Res. 2019; 39.
16. Black J, Cuddigan J; National Pressure Injury Advisory Panel Board of Directors. Skin manifestations with COVID-19: The purple skin and toes that you are seeing may not be deep tissue pressure injury. An NPIAP White Paper. National Pressure Injury Advisory Panel; 2020.
17. Espinosa OA, Zanetti ADS, Antunes EF, Longhi FG, Matos TA, BattagliniPF. Prevalence of comorbidities in patients and mortality cases affected by SARS-CoV-2: a systematic review and meta-analysis. Rev Inst Med Trop Sao Paulo. 2020; 62: e43.
18. Xie J, Wu W, Li S. Clinical characteristics and outcomes of critically ill patients with novel coronavirus infectious disease (COVID-19) in China: a retrospective multicenter study. Intensive Care Med. 2020; 46: 1863-1872.