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Theiler, Regan N.

https://orcid.org/0000-0002-3412-3653

Mayo Clinic

Mayo Clinic

Citations 29

Comparative value of growth velocity and umbilical artery Doppler for the prediction of adverse perinatal outcomes in growth‐restricted pregnancies
Salameh, Mohammad , Donigan, Emma C , Branda, Megan E. , Cooper, Kylie , Theiler, Regan N. , Brunton, Joshua , Larish, Alyssa , Branda, Megan , Theiler, Regan , Salameh, Mohammad A

Pregnancy | August 14, 2026 | Volume: 2 | Issue: 5 | Pages: No page available

10.1002/pmf2.70430 Get It

Abstract Introduction Fetal growth restriction (FGR) is associated with an increased risk of neonatal morbidity and mortality. Current diagnostic criteria for FGR do not discriminate between constitutionally small and pathologically restricted fetuses. Following FGR diagnosis, umbilical artery (UA) Doppler is utilized to monitor fetal well‐being, but its limitations have increased interest in investigating growth velocity as an adjunctive tool. The objective of this study is to compare the predictive ability of UA Doppler studies and growth velocity for adverse neonatal outcomes in growth‐restricted fetuses. Methods This is a secondary analysis of a cohort of pregnancies delivered in a single healthcare network from August 2017 to December 2022, diagnosed antenatally with FGR. The cohort was restricted to those with baseline estimated fetal weight (EFW) between the 3rd and 50th percentiles. All subjects had growth velocity measured (defined as EFW percentile change per week between baseline and subsequent ultrasound). The primary outcome was a composite of neonatal morbidity (neonatal intensive care unit [NICU] admission, low 5‐min Appearance, Pulse, Grimace, Activity, Respiration score [<7], intraventricular hemorrhage, necrotizing enterocolitis, or metabolic acidosis) and severe adverse perinatal events (stillbirth or neonatal death, hypoxic ischemic encephalopathy, mechanical ventilation, or severe metabolic acidosis [pH < 7.0]). Neonatal morbidity and severe adverse perinatal events were analyzed separately as secondary outcomes. Independence between growth velocity and S/D ratio was evaluated. Univariate logistic regression models were then performed, with each outcome of interest as the dependent variable and S/D ratio and growth velocity as independent variables. Receiver operating characteristic (ROC) curves were generated to compare the performance of both tests. Results A total of 172 patients were included in the analysis. UA Doppler data were available for 165 patients, 15.3% of whom had S/D ratio >95th percentile; none demonstrated absent or reversed end‐diastolic flow. There was no correlation observed between S/D ratio percentile and growth velocity, suggesting independence. ROC analysis demonstrated that the discriminatory ability of growth velocity was higher across outcomes with areas under the curve (AUC) ranging from 0.65 to 0.69 while AUC for S/D ratio percentiles ranged from 0.51 to 0.53, approximating the performance of chance. Higher growth velocity was significantly associated with reduced odds of the composite outcome (odds ratio [OR], 0.79; 95% confidence interval [CI], 0.69–0.90), and neonatal morbidity (OR, 0.84; 95% CI, 0.73–0.95). S/D ratio percentile was not associated with these outcomes. Conclusion In pregnancies complicated by growth restriction with forward UA flow, growth velocity outperformed S/D ratio percentile in predicting adverse outcomes. The two tests were independent, indicating that growth velocity may reflect a component of fetal development not captured by UA Doppler. These results suggest that growth velocity could be used in addition to UA Doppler studies for fetal risk assessment, especially in fetuses with forward arterial flow.
Percentile-Based Fetal Growth Velocity as a Predictor of Adverse Neonatal Outcomes in Fetal Growth Restriction and Small-for-Gestational-Age Pregnancies
Brunton, Joshua , Branda, Megan, Stetson, Raymond C. , Schenone, Mauro , Cooper, Kylie, Larish, Alyssa , Salameh, Mohammad , Branda, Megan E. , Schenone, Mauro H , Theiler, Regan N.

No container title available | July 31, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.64898/2026.07.29.26359259 Get It

Background: Pregnancies complicated by fetal growth restriction are at increased risk of fetal demise and adverse neonatal outcomes. Distinguishing growth-restricted fetuses from constitutionally small ones remains challenging. Given the variability in current diagnostic criteria and the importance of identifying at-risk fetuses, fetal growth velocity has emerged as a predictor of adverse neonatal outcomes. Objective: To evaluate whether percentile-based fetal growth velocity, defined as change in estimated fetal weight percentile per week, predicts adverse neonatal outcomes in pregnancies affected by fetal growth restriction or small-for-gestational-age neonates. The primary aim was to determine the relationship between growth velocity and a composite of adverse neonatal outcomes. Study Design: This was a retrospective cohort study of pregnant patients 18 - 45 years old who delivered between August 2017 to December 2022 in a single healthcare system. Patients were excluded who had fewer than 2 ultrasounds after 16 weeks gestation, genetic or anatomic abnormalities, or a multiple gestation. Results: 300 patients met all inclusion criteria, and most patients (n=199) delivered at the tertiary care center. Three had an intrauterine fetal demise at a mean gestational age of 35w3d. 74 neonates were admitted to the NICU with a mean length of stay of 8.5 days; 29 required respiratory support. No neonatal deaths occurred. In fetuses with initial estimated fetal weight <3rd percentile (n=33), the probability of composite outcome was increased (50%, 95% CI 44.8-55.2) compared to those >50th percentile (5%, 95% CI 3.7-6.6). In the 3-10th and 10 - 50th percentile subgroups with decelerated growth, composite outcome rates were also increased (56.2% and 44.1%) compared to those with neutral or increased growth velocity. Conclusion: Percentile-based fetal growth velocity is a simple calculation that correlates with adverse neonatal outcomes regardless of initial estimated fetal weight. As fetal growth velocity decreased, our cohort saw increased rates of adverse outcomes. Change in EFW percentile normalizes for gestational age and allows ease of clinical interpretation. Decelerated growth identified fetuses at highest risk, suggesting growth velocity as a useful metric in routine surveillance.
In Reply:
Chen, Valerie , Theiler, Regan N.

Obstetrics & Gynecology | June 18, 2026 | Volume: 148 | Issue: 1 | Pages: e61-e61

10.1097/aog.0000000000006317 Get It

Acute kidney injury in pregnancy is associated with increased risks for adverse maternal and neonatal outcomes: an integrated health system study
Kashani, Mehdi , Theiler, Regan N. , Bruns, Danette, Yousefi, Farbod , Kashani, Kianoush B

Journal of Nephrology | April 24, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1093/joneph/aajag125 Get It

Abstract Background Pregnancy-related acute kidney injury (PrAKI) is an uncommon but serious complication associated with adverse maternal and neonatal outcomes, with limited data in high-resource settings. Methods We conducted a retrospective cohort study of 29 586 deliveries at Mayo Clinic hospitals between 2017 and 2022. PrAKI was defined using Kidney Disease Improving Global Outcomes (KDIGO) creatinine criteria. Maternal characteristics, nephrotoxin exposure, clinical interventions, and neonatal outcomes were compared between patients with and without PrAKI. Results PrAKI occurred in 341 patients (1.15%). Compared with controls, PrAKI was associated with higher rates of chronic hypertension (28.7% vs 5.2%), cesarean delivery (68.5% vs 35.1%), intensive care unit (ICU) admission (59.1% vs 6.2%), and nephrotoxin exposure (58.7% vs 31.6%) (all P &lt; .0001). Dialysis was required in 7.1% of patients with PrAKI, with 1.17% remaining dependent at discharge and 0.88% at 30 and 90 days; no control patients required dialysis. Neonates of mothers with PrAKI had higher rates of prematurity and neonatal ICU (NICU) admission (48.7% vs 9.8%; P &lt; .0001). Maternal mortality was rare. Conclusions PrAKI is a marker of severe maternal illness and is associated with adverse maternal and neonatal outcomes. Although most patients recover kidney function, a subset develop persistent dysfunction. Early identification, cautious use of nephrotoxic medications, and structured postpartum follow-up are essential.
Hypertensive Disorders of Pregnancy: Factors Associated with Multiple Postpartum Blood Pressure Visits
Dyre, Lillian , Falde, Danielle L., Branda, Megan E. , Theiler, Regan N. , Tobah, Yvonne Butler , Rivera‐Chiauzzi, Enid Y. , Dyre, Lillian J , Butler Tobah, Yvonne S , Rivera-Chiauzzi, Enid Y , Branda, Megan , Theiler, Regan

American Journal of Perinatology | March 4, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1055/a-2809-6441 Get It

Abstract Patients with hypertensive disorders of pregnancy (HDPs) are recommended to attend an early postpartum follow-up visit for blood pressure monitoring. Follow-up frequency for patients with HDPs can vary widely, with some patients requiring multiple office visits. We sought to determine factors associated with multiple postpartum blood pressure visits among patients with HDPs. We retrospectively identified patients with HDPs who delivered at our maternity center in 2019 and compared factors between patients who attended a single blood pressure follow-up appointment without requiring further clinical evaluation for hypertension and patients who required multiple postpartum clinical evaluations for persistent hypertension. Univariate logistic regression models were used to identify factors associated with increased odds of having multiple clinically indicated postpartum visits for blood pressure monitoring. We identified 328 patients with HDPs, of whom 260 (79.3%) attended an initial postpartum blood pressure follow-up appointment and were included in further analyses. Of the 260 patients, 70 (26.9%) had multiple blood pressure visits. Factors associated with multiple blood pressure visits included delivery between 34 and less than 37 weeks of gestation (odds ratio [OR], 3.62; 95% CI, 1.07–12.30), systolic blood pressure before discharge of 140 mm Hg or higher (OR, 5.02; 95% CI, 2.57–9.82), and discharge with blood pressure medication (OR, 3.42; 95% CI, 1.82–6.41). Patients with HDPs who deliver preterm, have persistent hypertension before discharge, or are discharged with antihypertensive medication require continued close postpartum observation and continuity of care.
Language Proficiency and Maternal and Neonatal Adverse Outcomes: A Retrospective Cohort Study
Melson, Valerie A. , Gorman, Benjamin G. , Rajput, Sanjna , Lu, Lauren , Carranza, Leslie , Theiler, Regan N. , Melson, Valerie , VanLith, Caitlin J. , Branda, Megan E. , Theiler, Regan

BJOG: An International Journal of Obstetrics & Gynaecology | September 8, 2025 | Volume: 132 | Issue: 13 | Pages: 2226-2232

10.1111/1471-0528.18354 Get It

ABSTRACT Objective To compare maternal and neonatal adverse outcomes between women who are English proficient (EP) and those who have limited English proficiency (LEP). Design Retrospective cohort study. Setting Single US academic medical centre with interpreter services. Population All pregnant women with deliveries during the study period. Methods We retrospectively identified EP and LEP individuals (categorised by self‐report) who delivered at Mayo Clinic, Rochester, Minnesota, USA, from 2015 to 2019. Overall composite adverse outcomes, as well as maternal and neonatal composite outcomes, were measured with generalised linear models and logistic regression, reporting estimates and 95% CIs. Multivariable logistic regression analysis was used to assess associations between language proficiency and outcome measures while controlling for other clinical factors. Main Outcome Measures Composite overall, maternal and neonatal adverse outcomes. Results Among 10 427 EP and 900 LEP participants, the LEP group had a higher incidence of gestational diabetes, unplanned intensive care unit admission, uterine rupture, postpartum haemorrhage with transfusion, neonatal death and 5‐min Apgar score less than 7. The composite overall, maternal and neonatal adverse outcomes were more prevalent in the LEP group than the EP group in unadjusted analysis. Of these, the composite adverse outcome remained significant when the model was adjusted (odds ratio, 1.40; 95% CI, 1.03–1.90). Conclusions Pregnant women with LEP had increased incidence of adverse delivery outcomes, even in a setting with universal availability of medical interpreters.
Perinatal Immune Changes to Identify Patients at Risk of Postpartum Preeclampsia
Brien, Marie‐Eve , Boufaied, Inès, Rey, Évelyne , Girard, Sylvie , Theiler, Regan N. , Sylvie, Girard

American Journal of Hypertension | June 26, 2025 | Volume: 38 | Issue: 11 | Pages: 982-989

10.1093/ajh/hpaf122 Get It

Abstract BACKGROUND Postpartum preeclampsia (PPPE) is a maternal condition characterized by de novo hypertension in the postpartum period with end-organ damage. We investigated the use of perinatal immune changes, through routine complete blood count (CBC), to identify high-risk individuals before PPPE development. METHODS We performed a retrospective matched case-control study of 100 individuals with PPPE, 200 term pregnancies (Ctrl) and 200 antenatal preeclampsia (PE). Detailed demographic, obstetrical, and laboratory data were retrieved from medical records. Statistical analysis was performed using one-way ANOVA, multivariate regression, and paired or unpaired t-tests, as appropriate. RESULTS Individuals who developed PPPE were significantly older and predominantly Black vs Ctrl and PE. Both PE and PPPE had higher pre-pregnancy BMI and increased personal and family history of hypertension/PE vs Ctrl (P &lt; 0.001). Before delivery, individuals who later developed PPPE, had lower total leukocyte counts vs Ctrl (9.61 vs 10.75 × 109/L, P &lt; 0.05) whereas monocytes percentage was elevated (8.07 vs 7.27%, P &lt; 0.01). Comparing the postpartum/antenatal ratio in-between each condition revealed elevated leukocyte ratio in PPPE vs Ctrl (P &lt; 0.001). The Neutrophils ratio was also increased, whereas lymphocytes and monocytes were decreased in PPPE vs both Ctrl and PE. After adjusting for race, maternal age, pre-pregnancy BMI, personal history of PE/HT, and diabetes mellitus, perinatal immune changes were still significantly associated with PPPE. CONCLUSIONS Globally, perinatal immune changes were observed in individuals with a seemingly uncomplicated pregnancy prior to the development of PPPE. This strongly supports that such changes could be used to identify high-risk individuals prior to disease onset.
Uterine Rupture and Vaginal Birth After Cesarean Rate After Implementation of Restrictive Trial of Labor After Cesarean Induction of Labor Eligibility Policy [ID 961]
Nora, Anne E., Uwilingiyimana, Aimée, Nora, Anne, Uwilingiyimana, Aimée-Sandrine, Branda, Megan E. , Theiler, Regan N.

Obstetrics & Gynecology | May 15, 2025 | Volume: 145 | Issue: 6S | Pages: 25S-26S

10.1097/aog.0000000000005916.086 Get It

INTRODUCTION: After an increase in labor induction-associated uterine rupture cases, our institution implemented a restrictive trial of labor after cesarean (TOLAC) induction of labor (IOL) eligibility policy. The policy did not allow elective IOL to TOLAC patients and denied medically indicated IOL to patients who met any of the following criteria: two or more cesarean deliveries; body mass index greater or equal to 50 AND without a prior vaginal delivery; a priori predicted success rate of less than 60% AND Bishop score of less than 8. We investigated how this policy affected uterine rupture and VBAC rates. METHODS: This was a retrospective cohort of 4,356 participants with a prior cesarean delivery who delivered a subsequent neonate between 2011 and 2022. Uterine rupture rates were compared before and after implementation of the eligibility policy in 2018. The primary outcomes were uterine rupture and rates of VBAC. Multivariable logistic regression was performed. RESULTS: The uterine rupture rate decreased by 50% after implementation of eligibility criteria (0.9% pre-policy, 0.5% post-policy). The VBAC rate decreased from 30% to 25%, whereas the unsuccessful TOLAC rate decreased from 7.3% to 5%. CONCLUSIONS/IMPLICATIONS: This study supports previous studies that demonstrate IOL in TOLAC patients may increase the risk of uterine rupture. Restrictive criteria for IOL in TOLAC patients decreased the rates of uterine rupture and unsuccessful TOLAC, however decreased the overall VBAC rate. Uterine rupture is a rare, yet catastrophic event, and more studies are needed to develop policies that minimize risk to TOLAC patients and maximize VBAC rates.
Enhancing the utility of placental pathology reports for clinical use
Santos, Janelle, Szymanski, Linda M. , Enninga, Elizabeth Ann L. , Mcduffie, Molly, Bulawa‐Regner, Lainee A., Cheek‐Norgan, E. Heidi, Lamppa, Julie A., Wick, Myra , Theiler, Regan N. , Bulawa-Regner, Lainee A, Cheek-Norgan, E Heidi, Enninga, Elizabeth Ann L , Norgan, Andrew P. , Mcduffie, Molly

Pregnancy | May 5, 2025 | Volume: 1 | Issue: 3 | Pages: No page available

10.1002/pmf2.70029 Get It

Abstract Obstetric training programs typically offer limited formal education on placental pathology; yet, in practice, obstetric providers are expected to incorporate placental pathology findings into the overall evaluation of obstetric complications. In this narrative review, we briefly review pathology classifications and then delve deeper into pathology findings that may change clinical decision‐making, specifically highlighting pathologic lesions with a recurrence risk and recommended management for subsequent pregnancies. Last, we present specific recommendations on how to improve clinical interpretability and utility of placental pathology reports for obstetrical practice.
Leveraging In Situ Simulation for Implementation of Teleobstetric Consultation Services in Rural and Community Hospitals
Schoen, Jessica C. , Klipfel, Janee M., Torbenson, Vanessa E. , DeWitt, Jason, Sadosty, Anne T., Theiler, Regan N. , DeWitt, Jason J, Theiler, Regan

Telemedicine and e-Health | July 1, 2024 | Volume: 30 | Issue: 8 | Pages: No page available

10.1089/tmj.2023.0649 Get It

Background: Our institution implemented acute-care obstetric (OB) telemedicine (TeleOB) to address rural disparities across our health system. We sought to determine whether in situ simulations with embedded TeleOB consultation increase participants’ comfort managing OB emergencies and comfort with and likelihood of using TeleOB. Methods: Rural site care teams participated in multidisciplinary in situ OB emergency simulations. Physicians in OB and neonatology at the referral center assisted via telemedicine consultation. Participants were surveyed before and after the simulations and six months later regarding their experience during the simulations. Results: Participants reported increased comfort with TeleOB activation, indications, and workflow processes, as well as increased comfort managing OB emergencies. Participants also reported significantly increased likelihood of using TeleOB in the future. Conclusions: Consistent with previous work, in situ simulation with embedded telemedicine consultations is an effective approach to facilitate telemedicine implementation and promote use by rural clinicians.