Early Clinical Outcomes in Infants with Prenatally Diagnosed Perimembranous and Muscular Ventricular Septal Defects (VSDs).

Isolated ventricular septal defect (VSD) is often associated with good clinical outcomes. However, infants prenatally diagnosed with VSD are often recommended for delivery at tertiary care centers. The aim of our study was to determine the odds of neonatal intensive care unit (NICU) admission in infants with persistent isolated VSD and complicated VSD, where an infant is affected by VSD and other genetic/structural abnormalities. We performed a retrospective cohort study, with data collected from a single academic institution from June 2018 to March 2023. Individuals with prenatally diagnosed VSD, in the absence of any other heart defects, were included in this study. The primary outcome was admission to the NICU. Multivariable logistic regression was used to assess associations. The association between persistence of VSD and NICU admission was adjusted for maternal age, fetal genetic abnormalities, fetal extracardiac abnormalities, and gestational age at the time of delivery. The association between complicated VSD and NICU admission was adjusted for maternal age and gestational age of the infant at the time of delivery. The odds of NICU admission were similar in infants with persistent isolated VSD and VSD that closed in utero (adjusted OR 1.31, 95% CI 0.30-5.61). However, infants with complicated VSD were at increased risk of NICU admission (adjusted OR 15.52, 95% CI 2.90-82.92). The risk of NICU admission was only increased in infants whose VSD was complicated by another genetic/major structural abnormalities. Therefore, women whose infants are prenatally diagnosed with VSD alone may not require delivery at tertiary care centers.

Multimodal prenatal and postnatal imaging of microphthalmia with cyst.

Congenital ocular anomalies may be detected on prenatal imaging using fetal ultrasound and magnetic resonance imaging (MRI), although standard prenatal ultrasound for fetal physical development does not currently include ocular and orbital evaluation. We present the case of a male infant born at 39 weeks' gestation with microphthalmia with cyst that was characterized using serial multimodal imaging, including fetal ultrasound and MRI, B-scan ultrasonography, ultrasound biomicroscopy, and postnatal MRI. Multiple prenatal and postnatal imaging modalities yielded comparable evaluations of the ocular and orbital pathology, validating the prenatal assessments.

B-Flow/Spatiotemporal Image Correlation M-Mode and Contrast-Enhanced/Microbubble Ultrasonography Quantification of Spiral Artery Distensibility and Placental Intervillous Perfusion in the First Trimester in a Primate Model of Impaired Spiral Artery Remodeling.

OBJECTIVE: During early human pregnancy, placental trophoblasts remodel spiral arteries into distensible low-resistance vessels to promote placental perfusion. We have established a model of impaired spiral artery remodeling (SAR) by elevating estradiol levels in the first trimester of baboon pregnancy. In the present study, B-flow/spatiotemporal image correlation (STIC) M-mode ultrasonography, a non-Doppler technology for sharp rendering of vessel dimensions, was used to determine whether spiral artery distensibility was altered in SAR-suppressed baboons. Contrast-enhanced ultrasound/microbubble imaging was also performed to determine whether it detected changes in placenta intervillous space perfusion in SAR-suppressed baboons. METHODS: The two imaging procedures were performed in the first trimester in baboons not treated or treated with estradiol to suppress SAR. RESULTS: Spiral artery distensibility, that is, luminal diameter at systole minus diameter at diastole, and volume flow as quantified by B-flow/STIC M-mode were 26% (p = 0.03) and 55% (p = 0.059) lower, respectively, in SAR-suppressed baboons. However, placental intervillous space flow rate and video intensity plateau levels reflecting blood perfusion, quantified by contrast-enhanced ultrasound/microbubble imaging, were unaltered in SAR-suppressed baboons. CONCLUSION: The results indicate that B-flow/STIC M-mode ultrasonography provides a non-invasive method to detect reduced distensibility and, thus, function of spiral arteries across the cardiac cycle in the first trimester in a primate model of impaired SAR. This study represents a first step in determining whether B-flow/STIC M-mode detects a similar defect in SAR early in adverse human pregnancy. This would provide an avenue to develop therapeutic modalities to prevent the devastating consequences of impaired SAR.

The impact of early diagnosis of fetal single-ventricle cardiac defects on reproductive choices.

BACKGROUND: Congenital heart defects are the most common fetal anomaly. Congenital heart defects with single-ventricle cardiac defects have high mortality rates, and in pregnancies diagnosed with this condition, patients are often offered termination of pregnancy as an option. OBJECTIVE: This study aimed to investigate the relationship between gestational age at diagnosis and reproductive choices in fetuses diagnosed with single-ventricle cardiac defects. STUDY DESIGN: This was a retrospective single-center cohort study in which 158 patients with a fetal diagnosis of single-ventricle cardiac defects were reviewed. Cases were categorized as isolated or complex. Complex cases included fetuses with single-ventricle cardiac defects in addition to other fetal extracardiac anomalies or chromosomal abnormalities. RESULTS: A total of 158 patients were diagnosed with single-ventricle cardiac defects during the study period. Of those patients, 37 (23.4%) underwent termination of pregnancy, 113 (71.5%) delivered, and 8 (5.1%) had an intrauterine fetal demise. Gestational age at diagnosis and race were significant predictors of the termination decision. The median gestational age at diagnosis was earlier in the termination of pregnancy group (20.4 vs 23.6 weeks; P<.001). Pregnancies complicated by single-ventricle cardiac defects diagnosed in early gestation (11 0/7 to 14 5/7 weeks of gestation) were more likely to be terminated than pregnancies complicated by single-ventricle cardiac defects diagnosed in middle gestation (15 0/7 to 27 5/7 weeks of gestation) and late gestation (≥28 weeks of gestation) (54.2% vs 23.2% and 2.9%; P<.001). Earlier gestational age at diagnosis was correlated with earlier gestational age at termination (r=0.92; P<.001). CONCLUSION: Termination of pregnancy was more common when the single-ventricle cardiac defect was diagnosed earlier in pregnancy. This could be explained by the fact that early diagnoses allow parents to make deliberate and informed decisions.

The value of detailed first-trimester ultrasound in the era of noninvasive prenatal testing.

BACKGROUND: In 2020, the American College of Obstetricians and Gynecologists recommended noninvasive prenatal testing be offered to all patients. However, current societal guidelines in the United States do not universally recommend a detailed first-trimester ultrasound. OBJECTIVE: This study aimed to determine the additional findings identified through first-trimester ultrasound that would have otherwise been missed if noninvasive prenatal testing was used alone as a first-trimester screening method. STUDY DESIGN: This was a retrospective cohort study involving 2158 pregnant patients and 2216 fetuses that were seen at a single medical center between January 1, 2020, and December 31, 2022. All those included underwent both noninvasive prenatal testing and detailed first-trimester ultrasound between 11.0 and 13.6 weeks of gestation. Noninvasive prenatal testing results were categorized as low risk or high risk, and first-trimester ultrasound results were categorized as normal or abnormal. Abnormal first-trimester ultrasounds were further classified as first-trimester screening markers (increased nuchal translucency, absent nasal bone, tricuspid regurgitation, and ductus venosus reverse a-wave) or structural defects (the cranium, neck, heart, thorax, abdominal wall, stomach, kidneys, bladder, spine, and extremities). Descriptive statistics were used to report our findings. RESULTS: Of 2216 fetuses, 65 (3.0%) had a high-risk noninvasive prenatal testing result, whereas 2151 (97.0%) had a low-risk noninvasive prenatal testing result. Of those with a low-risk noninvasive prenatal testing result, 2035 (94.6%) had a normal first-trimester ultrasound, whereas 116 (5.4%) had at least 1 abnormal finding on first-trimester ultrasound. The most common screening marker detected within the low-risk noninvasive prenatal testing group was absent nasal bone (52/2151 [2.4%]), followed by reversed a-wave of the ductus venosus (30/2151 [1.4%]). The most common structural defect in this group was cardiac abnormality (15/2151 [0.7%]). Overall, 181 fetuses were identified as having "abnormal screening" through either a high-risk noninvasive prenatal testing result (n=65) or through a low-risk noninvasive prenatal testing result but abnormal first-trimester ultrasound (n=116). In summary, the incorporation of first-trimester ultrasound screening identified 116 additional fetuses (5.4%) that required further follow-up and surveillance than noninvasive prenatal testing alone would have identified. CONCLUSION: Detailed first-trimester ultrasound identified more fetuses with a potential abnormality than noninvasive prenatal testing alone. Therefore, first-trimester ultrasound remains a valuable screening method that should be used in combination with noninvasive prenatal testing.

The impact of trimester of COVID-19 infection on pregnancy outcomes after recovery.

OBJECTIVES: Many physiological adaptations occur during pregnancy. It is not currently known how timing of COVID-19 infection impacts pregnancy. We hypothesize that maternal and neonatal outcomes are different if COVID-19 infection occurs in different trimesters of pregnancy. METHODS: This retrospective cohort study was conducted from 3/2020 to 6/2022. Pregnant patients with a positive COVID-19 infection more than 10 days before delivery (COVID-recovered) were identified and grouped by trimester of infection. Demographics and maternal, obstetric, and neonatal outcomes were analyzed. ANOVA, Wilcoxon rank-sum test, Pearson's chi-squared test, and Fisher's exact test were used to compare continuous and categorical data. RESULTS: A total of 298 COVID-recovered pregnant patients were identified. Of those, 48 (16 %) were infected in the 1st trimester, 123 (41 %) in the 2nd, and 127 (43 %) in the 3rd. There were no significant demographic differences between the study groups. Vaccination status was similar. Hospital admission rate and the need for oxygen therapy while infected were significantly higher in patients with 2nd or 3rd trimester infection (18 % & 20 % vs. 2 % and 13 % & 14 % vs. 0 %, respectively). Rates of preterm birth (PTB) and extreme PTB were higher in the 1st trimester infection group. Infants born to mothers infected in the 2nd trimester had more neonatal sepsis workups (22 % vs. 12 % & 7 %). Other outcomes were similar between groups. CONCLUSIONS: First trimester COVID-recovered patients were more likely to have a preterm birth despite having lower rates of hospital admission and oxygen supplementation while infected than patients who recovered from a 2nd or 3rd trimester infection.

A pilot study: Application of paired ultrasound simulator training in obstetrics.

OBJECTIVE: Medical trainees in obstetrics must develop competency in fetal ultrasonography. To date, no studies have utilized ultrasound simulator training for basic fetal anatomy with paired didactic coursework. We hypothesize that ultrasound simulator training with paired didactics improves medical trainee competency in fetal ultrasonography. METHODS: A prospective observational study was performed at a tertiary care center during the 2021-2022 academic year. Medical trainees in obstetrics without prior simulator experience could participate. Participants completed ultrasound simulator training with standardized paired didactics and subsequent real-time patient scanning. All images were reviewed by the same physician for competency. Trainees completed 11-point Likert scale surveys at three time points: pre-simulator, post-simulator, and post-real-time patient scanning. Two-tailed student's t-tests with 95% confidence intervals were performed, and p-values <0.05 were considered significant. RESULTS: Of the 26 trainees that completed the training, 96% reported that simulation positively impacted their confidence and ability to perform real-time scanning of patients. Self-reported knowledge of fetal anatomy, ultrasound techniques, and application to clinical obstetrics all significantly increased after simulator training (p < 0.01). CONCLUSIONS: Paired ultrasound simulation with didactic instruction significantly improves medical trainees' knowledge of fetal anatomy and ability to perform fetal ultrasonography. Implementing an ultrasound simulation curriculum may become an essential tool for obstetric residency programs.

Topography of the Heart: Mapping the Fetal Heart Through SlowflowHD.

SlowflowHD is a Doppler Ultrasound modality that is typically geared toward visualization of small-size vessels and low velocity blood flow. In this commentary, we emphasize the importance of implementing the use of SlowflowHD as an adjunct to traditional Doppler modalities in the echocardiography screening in both the first and second trimester. This modality carries many characteristics that allow it to overcome the limitations of our current ultrasound modalities and facilitate mapping of the entirety of the fetal heart. The clinical implications are significant in regard to earlier acquisition of diagnostic information to guide decision-making and patient counseling.

The Impact of Neighborhood Socioeconomic Status, Race and Ethnicity, and Language on Prenatal Diagnosis of CHD.

Congenital heart disease (CHD) is the most prevalent birth defect. This study aimed to assess whether prenatal diagnosis (PD) of CHD and time of the diagnosis are associated with maternal race, ethnicity, neighborhood SES, and language. In this retrospective cohort study, we analyzed data on 163 patients who underwent surgical intervention for CHD within 30 days of birth between 2011 and 2020 at the University of Maryland Children's Hospital. A neighborhood SES score was calculated using the mother's address at time of discharge and 6 SES variables from the US Census block group data with a previously published method by Diez Roux et al. Neighborhood SES did not impact the likelihood of receiving a PD of CHD; however, patients of Latino ethnicity were 3.2 times and non-English-preferred language patients were 5.1 times more likely to not receive a PD. Patients whose preferred language was a non-English language received a prenatal diagnosis 5.3 weeks later, resulting in the PD being made in the third trimester rather than the second. Patients from the highest quartile SES received an earlier prenatal diagnosis, although this association was less significant when controlling for insurance type and preferred language. Significant disparities in PD of CHD were seen in patients of Latino ethnicity and patients who prefer non-English language. Better understanding of the root causes of these disparities will be important to guide interventions to reduce these disparities.

Genome Editing and Myocardial Development.

Congenital heart disease (CHD) has a strong genetic etiology, making it a likely candidate for therapeutic intervention using genetic editing. Complex genetics involving an orchestrated series of genetic events and over 400 genes are responsible for myocardial development. Cooperation is required from a vast series of genetic networks, and mutations in such can lead to CHD and cardiovascular abnormalities, affecting up to 1% of all live births. Genome editing technologies are becoming better studied and with time and improved logistics, CHD could be a prime therapeutic target. Syndromic, nonsyndromic, and cases of familial inheritance all involve identifiable causative mutations and thus have the potential for genome editing therapy. Mouse models are well-suited to study and predict clinical outcome. This review summarizes the anatomical and genetic timeline of myocardial development in both mice and humans, the potential of gene editing in typical CHD categories, as well as the use of mice thus far in reproducing models of human CHD and correcting the mutations that create them.

Temporal Trend of COVID-19 Clinical Severity and the Ethnic/Racial Disparity: A Report from the Maryland Study Group.

OBJECTIVES: This study aimed to evaluate the temporal trend of novel coronavirus disease 2019 (COVID-19) symptoms and severity of clinical outcomes among pregnant women over a calendar year in the State of Maryland and compare clinical outcomes between different ethnic and racial groups. STUDY DESIGN: We conducted a retrospective, multicenter observational study of the temporal trend of COVID-19 clinical presentation during pregnancy in the State of Maryland. We reviewed consecutive charts of adult pregnant females, aged 18 to 55 years, with laboratory-confirmed severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection between March 1, 2020, and February 28, 2021, and managed within the University of Maryland Medical System and Johns Hopkins Medicine. We excluded cases with insufficient data for assessing the COVID-19 diagnosis, pregnancy status, or clinical outcomes. We evaluated the evolution of COVID-19 symptoms at the time of presentation. Also, we compared COVID-19 infection rate, hospitalization rate, oxygen use, and intensive care unit (ICU) admission rates between different ethnic and racial groups. RESULTS: We included 595 pregnant women with laboratory-confirmed COVID-19 over the study period. The prevalence of respiratory and systemic symptoms decreased over time with incidence rate ratios (IRRs) of 0.91 per month (95% confidence interval [CI]: 0.88-0.95) and 0.87 per month (95% CI: 0.83-0.95), respectively. The prevalence of hospitalization, O2 requirement, and ICU admission decreased over time with IRRs of 0.86 per month (95% CI: 0.82-0.91), 0.91 per month (95% CI: 0.84-0.98), and 0.70 per month (95% CI: 0.57-0.85), respectively. The Hispanic and Black populations had a higher COVID-19 infection rate and hospitalization rate than the non-Hispanic White population (p = 0.004, < 0.001, and < 0.001, respectively). CONCLUSION: Understanding the concepts of viral evolution could potentially help the fight against pandemics like COVID-19. Moreover, this might improve the knowledge of how pandemics affect disadvantaged populations and help close the gap in health care inequities. KEY POINTS: · A trade-off between virulence and transmissibility is determined by the natural selection of viruses.. · Understanding the concepts of viral evolution can help the fight against pandemics like COVID-19.. · Evolution of SARS-CoV-2 over time resulted in decreased virulence and increased infectivity..

SARS-CoV-2 infection induces activation of ferroptosis in human placenta.

Ferroptosis, a regulated non-apoptotic form of cell death, has been implicated in the response to varied types of infectious agents including virus. In this study, we sought to determine whether SARS-CoV-2 infection can induce activation of ferroptosis in the human placenta. We collected placentas from 23 pregnant females with laboratory-confirmed SARS-CoV-2 following delivery and then used RNA in situ hybridization assay for detection of viral positive-sense strand (PSS) to confirm that these placentas have been infected. We also used immunohistochemistry assay to assess expression levels of acyl-CoA synthetase long-chain family member 4 (ACSL4), an essential executioner of ferroptosis in the same specimens. Our results showed that ACSL4 expression was significantly increased in the group with positive positive-sense strand staining compared to their negative counterparts (p = 0.00022). Furthermore, we found that there was a positive trend for increased PSS staining along with increased ACSL4 expression. Our study supports that ferroptosis is activated in the response to SARS-CoV-2 infection in the human placenta, highlighting a molecular mechanism potentially linking this coronavirus infection and pathogenesis of adverse pregnancy outcomes.

Prenatal diagnosis of a germline variant in TRAF7: Importance of accessibility to prenatal exome sequencing in cases of structural fetal anomalies.

Diagnosis of a pathogenic germline TRAF7 missense variant (c.1555 C > T, p.L519F) made on a prenatal basis by exome sequencing (ES) performed on chorionic villi. This case highlights the importance of both higher-level prenatal ultrasounds and the accessibility of ES in making genetic diagnoses in making pregnancy management decisions.

First trimester examination of fetal anatomy: clinical practice guideline by the World Association of Perinatal Medicine (WAPM) and the Perinatal Medicine Foundation (PMF).

This recommendation document follows the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation. We aim to bring together groups and individuals throughout the world for precise standardization to implement the ultrasound evaluation of the fetus in the first trimester of pregnancy and improve the early detection of anomalies and the clinical management of the pregnancy. The aim is to present a document that includes statements and recommendations on the standard evaluation of the fetal anatomy in the first trimester, based on quality evidence in the peer-reviewed literature as well as the experience of perinatal experts around the world.

Accuracy of the Standardized Early Fetal Heart Assessment in Excluding Major Congenital Heart Defects in High-Risk Population: A Single-Center Experience.

OBJECTIVE: To evaluate the ability of standardized early fetal heart assessment (EFHA) that includes the 4-chamber view, outflow tract relationship (OTR), and transverse arches views (TAV) of the great arteries in excluding major congenital heart defects (CHDs) in high-risk populations. METHODS: This retrospective study included high-risk pregnancies for CHDs undergoing EFHA at 11-14 weeks of gestation. Risk factors for CHDs were diabetes mellitus, a family history of CHDs, a history of a CHD use of teratogenic medications, seizure disorder, assisted reproductive treatment-conceived pregnancy, presence of at least one of the ultrasound markers: enlarged nuchal translucency (>95th percentile), tricuspid regurgitation, and reversed a-wave in the ductus venosus, presence of an extracardiac or a suspected cardiac anomaly, a high-risk first trimester combined screen result, and multiple pregnancies. EFHA consisted of visualization of 4ChV, OTR, and TAV, with and without power Doppler ultrasound. The primary outcome was the negative predictive value of EFHA in excluding major CHDs. RESULTS: EFHA was performed on 1055 fetuses. Of these, 1024 were used for the final analysis. Of these, 94.9% (n = 923) were singleton. The most common indication for EFHA was maternal DM (n = 231, 22.6%). The sensitivity, specificity, false positive, false negative, and accuracy of EFHA were 93.2%, 99.9%, 1.4%, 0.4%, and 99.5% (P < .0001), respectively, in entire included cases. The performance of EFHA was 88%, 99.9%, 1.4%, 0.4%, and 99.5% (P < .0001) respectively when the terminated cases were excluded. CONCLUSION: Early fetal heart assessment is feasible for screening for major CHDs in high-risk populations. This approach may be expanded to the general obstetric population.

An initiative to evaluate the safety of maternal bonding in patients with SARS-CoV-2 infection.

BACKGROUND: In the last two decades, the world faced three epidemics caused by novel coronaviruses, namely, SARS-CoV in 2002, MERS-CoV in 2012, and the ongoing SARS-CoV-2 that started in late 2019. Despite a growing understanding of SARS-CoV-2 virology, epidemiology, and clinical management strategies, other aspects, such as mode of delivery, vertical transmission, and maternal bonding, remain controversial. The question we faced upon the decision to separate the neonates of SARS-CoV-2 positive mother is whether we follow the principle of "do no harm"? METHODS: This is a quality improvement project that analyzed all cases of SARS-CoV-2 positive pregnancies that delivered at a major health care system from March 1, 2020 to June, 1 2020. The article was prepared following Standards for Quality Improvement Reporting Excellence (SQUIRE) 2.0 guidelines. Data were prospectively collected and entered into the Research Electronic Data Capture (REDCap). Maternal bonding was defined by events such as rooming-in, skin to skin contact (STSC), and breastfeeding. Descriptive analysis was performed using the same software platform. INTERVENTION: We compared neonatal transmission rates between those neonates who experienced bonding versus those who were separated. RESULTS: A total of 1989 women were screened for SARS-CoV-2, from which 86 tested positive. Out of 31 analyzed pregnancies, five women (16%) were admitted to ICU and required mechanical ventilation. From the remaining 26 (84%), 17 (65%) opted for rooming-in, 12 (46%) for STSC, and 16 (61%) fed the infants with breastmilk (11 direct breastfeedings and five pumped the breast milk). All neonatal tests for SARS-CoV-2 returned negative. CONCLUSION: Our results have illustrated that maternal bonding appears safe in neonates born to mothers that are SARS-CoV-2 positive.

The rate of undetectable genetic causes by Cell-free DNA test in congenital heart defects.

OBJECTIVE: The study aimed to estimate the rate of genetic causes that were undetectable by Cell-free DNA (cfDNA) test in prenatally diagnosed congenital heart defect (CHD) cases based on an assumption that cfDNA would accurately detect common aneuploidies including trisomy 21/18/13/45X, and del22q11.2. METHODS: This study included prenatally diagnosed CHD cases with diagnostic genetic results. The possibility of false-positive/negative results from cfDNA testing was discarded. Thus, cfDNA results would be positive in common aneuploidies or del22q11.2 and negative in normal diagnostic genetic testing results or other genetic conditions. The rate of genetic causes that were undetectable by cfDNA test was estimated for all cases as well as for CHD subgroups. RESULTS: Of 302 cases, 98 (34.8%) had a type of genetic abnormalities, with 67 having common aneuploidies or del22q11.2 and 31 having other genetic conditions. The rate of genetic causes that were undetectable by cfDNA test in CHD cases was 13.2% among those with assumingly negative cfDNA screen results and 10.3% among the entire study population. These rates were similar between CHD subgroups (p > .05). The rate of genetic causes that were undetectable by cfDNA test was higher in the non-isolated cases than in the isolated ones among those with assumingly negative-screen results (20.5% and 9.9%, respectively, p = .025). CONCLUSION: In prenatally diagnosed CDH cases, a significant number of chromosomal abnormalities are still identified after diagnostic testing even if cfDNA screen is negative, and thus it is important to extensively counsel patients with negative cfDNA screen carrying a CHD-affected fetus.

Proning modus operandi in pregnancies complicated by acute respiratory distress syndrome secondary to COVID-19.

INTRODUCTION: Prone positioning has been widely utilized in ARDS management before and during the COVID-19 pandemic due to its demonstrated mortality benefits. In pregnancy, proning requires careful attention to often overlooked physiologic changes in pregnancy and additional technical challenges accompanying a gravid abdomen. The purpose of this manuscript is to demonstrate a proning technique that was successfully used at our institution to avoid premature delivery of the fetus while improving maternal outcomes. All technical challenges are addressed in the instructional videos using a pregnant model with twin gestation at 32 weeks. METHODS: We reviewed all the patients' charts with positive SARS-CoV-2 from March 2020 until July 2020 and identified those who developed ARDS. Subsequently, we identified four patients that were proned during the antepartum period. We described their clinical course, including the change in ventilatory parameters in relationship with proning timing. Stepwise instructions for self-proning and proning in mechanically ventilated patients are illustrated in video format. RESULTS: During the study period, we identified 100 pregnant patients with SARS-CoV-2 infection. Mechanical ventilation was required in 8 of these patients. In four cases, proning was performed during the antepartum period. We were able to improve the P/F ratio while decreasing FiO2 and avoiding iatrogenic preterm delivery. Except for one case, where the patient self-extubated and required emergent delivery, all patients were successfully extubated, followed for prenatal care, and delivered for usual obstetric indications. CONCLUSION: Proning remains a well-proven intervention in ARDS and should be considered in pregnant women when indicated. We recognize that proning might not be effective in all cases. However, proning positioning is an option to improve oxygenation in patients with severe hypoxemia when the next consideration is delivery of a premature infant or maternal cannulation for extracorporeal membrane oxygenation.