Significance of the sFlt-1/PlGF Ratio in Certain Cohorts - What Needs to be Considered?

The sFlt-1/PlGF ratio is an established tool in clinical practice, where it is part of a diagnostic algorithm and informs the prognosis of preeclampsia (PE). Maternal and gestational comorbidities can affect the performance of the sFlt-1/PlGF ratio and its constituent elements, and a good understanding of the potential pitfalls is required. The objective of this paper was to provide a current narrative review of the literature on the diagnostic and predictive performance of the sFlt-1/PlGF ratio in specific patient cohorts. Potential factors which can negatively affect the clinical interpretability and applicability of the sFlt-1/PlGF ratio include chronic kidney disease, twin pregnancy, and maternal obesity. Pathophysiological mechanisms related to these factors and disorders can result in different concentrations of sFlt-1 and/or PlGF in maternal blood, meaning that the use of standard cut-off values in specific cohorts can lead to errors. To what extent the cut-off values should be adapted in certain patient cohorts can only be clarified in large prospective cohort studies. This applies to the use of the ratio both for diagnosis and prognosis.

Stillbirth in women with Type 1 Diabetes mellitus-still a current topic.

PURPOSE: Compared to the general stillbirth rate in Germany for term deliveries of 0.12% the risk in type 1 diabetes mellitus is reported to be up to ten times higher. The reasons for this excess risk of intrauterine demise are still not fully elucidated. Risk factors named in the literature include poor glycemic control before and during pregnancy and the occurrence of ketoacidosis. Additionally there might be a diabetes related type of placental dysfunction leading to organ failure in late pregnancy. Understanding the underlying causes is mandatory to develop strategies to reduce the incidences. The Purpose of this publication is to point out the difficulties in prediction of intrauterine death in pregnant type 1 diabetes patients and thus emphasizing the necessity of constant awareness to all caregivers. METHODS: We present a case series of four cases of stillbirth that occurred in patients with type 1 diabetes mellitus at our tertiary care obstetric unit during a five-year period. RESULTS: In all four presented cases the underlying cause of intrauterine demise was different and we could not find a common mechanism or risk profile. Furthermore, established monitoring tools did not become peculiar to raise awareness. We compared our cases to published data. Underlying causes of intrauterine death in type 1 diabetes are discussed in the light of the current literature. CONCLUSIONS: The main risk factors of stillbirth in diabetic pregnancies are high maternal blood glucose levels including pre-conceptional HbA1c and diabetic ketoacidosis. Late acute placental insufficiency are associated with intrauterine death in type 1 diabetes. Despite the elevated risk of near term intrauterine demise there are currently no guidelines on how to monitor pregnancies in type 1 diabetes for fetal distress during the third trimester. Established thresholds for fetal Doppler data indicating fetal distress in normal and growth restricted fetuses may not be applicable for overgrown fetuses. Future research on how to monitor the diabetic fetus needs to be initiated.

Pentaerythrityl tetranitrate improves the outcome of children born to mothers with compromised uterine perfusion-12-months follow-up and safety data of the double-blind randomized PETN trial.

BACKGROUND: This is a follow-up study to the pentaerythrityl tetranitrate randomized controlled multicenter trial that reports neonatal outcome data of newborns admitted to neonatal intensive care units and outcome data of the offspring at 12 months of age. OBJECTIVE: We present data on adverse events reported during the study to document the safety of pentaerythrityl tetranitrate treatment during pregnancy. To further evaluate the effects of pentaerythrityl tetranitrate on neonatal and long-term outcomes, we present follow up data from of 240 children at 12 months of age, including information on height, weight, head circumference, developmental milestones, and the presence of chronic disease and of 144 newborns admitted to the neonatal intensive care unit during the trial. STUDY DESIGN: The pentaerythrityl tetranitrate trial was a randomized, double-blind, placebo-controlled study designed to assess the efficacy and safety of the nitric oxide-donor pentaerythrityl tetranitrate in the prevention of fetal growth restriction and perinatal death in pregnancies complicated by abnormal placental perfusion. RESULTS: Results at 12 months demonstrated that significantly more children were age appropriately developed without impairments in the pentaerythrityl tetranitrate group (P=.018). In addition, the presence of chronic disease was lower in the pentaerythrityl tetranitrate group (P=.041). Outcome data of the 144 newborns admitted to the neonatal intensive care unit did not reveal differences between the treatment and placebo groups. There were no differences in the number or nature of reported adverse events between the study groups. CONCLUSION: The analysis shows that study children born in the pentaerythrityl tetranitrate cohort have a clear advantage compared with the placebo group at the age of 12 months, as evidenced by the increased incidence of normal development without the presence of chronic disease. Although safety has been proven, further follow-up studies are necessary to justify pentaerythrityl tetranitrate treatment during pregnancies complicated by impaired uterine perfusion.

A liquid chromatographic-mass spectrometric procedure for analysis of pentaerythrityl tetranitrate metabolites - Development, validation and application to ovine serum and human plasma samples.

Pentaerythrityl tetranitrate (PETN) is an established drug in the treatment of coronary heart disease and heart failure. It is assumed, that the vasodilative and vasoprotective effects of PETN also have a positive impact on pregnant patients with impaired placental perfusion and studies evaluating the effect of PETN in risk pregnancies have been carried out. In the context of these clinical trials, measuring of serum levels of PETN and its metabolites pentaerythrityl trinitrate (PETriN), pentaerythrityl dinitrate (PEDN), pentaerythrityl mononitrate (PEMN) and pentaerythritol (PE) were required. To evaluate the transfer of PETN and its metabolites (PEXN) from the mother to the fetus using samples from a human clinical trial and animal study, the present work aimed to develop a rapid and simple method to simultaneously analyze PEXN in human and ovine samples. A method employing a rapid and simple liquid-liquid extraction followed by reversed-phase (C18) liquid chromatography coupled to high-resolution mass spectrometry with negative electrospray ionization was developed and validated for the detection of PETN and PEXN in human and ovine samples. PE could only be qualitatively detected at higher concenrations. Method validation requirements, including accuracy, repeatability and intermediate precision were fulfilled in ovine and human samples for all other PEXN with exception PETriN in human samples. The recovery (RE) in ovine samples was 76.7 % ± 12 % for PEMN, 98 % ± 23 % for PEDN, 94 % ± 22 % for PETriN, in human samples RE was 59 % ± 16 % for PEMN, 67 % ± 19 % for PEDN, 71 % ± 17 %. The matrix effects (ME) in ovine samples were 90 % ± 11 % for PEMN, 70 % ± 30 % for PEDN, 107 % ± 17 % for PETriN, in human samples the ME were 93 % ± 13 % for PEMN, 84 % ± 17 % for PEDN, 98 % ± 16 % for PETriN. The limits of quantification (LOQ) in ovine samples were 1.0 ng/mL for PETriN and 0.1 ng/mL for PEMN and PEDN. The LOQs in human samples were 5.0 ng/mL for PETriN and 0.3 ng/mL for PEMN und PEDN. The newly developed method was used to analyze 184 ovine serum samples and 18 human plasma samples. In ovine maternal samples, the highest observed PEDN concentration was 3.5 ng/mL and the highest PEMN concentration was 10 ng/mL, the respective concentrations in fetal serum samples were 4.9 ng/mL for PEDN and 5.4 ng/mL for PEMN. PETriN was only detected in traces in maternal and fetal samples, whereas PETN could not be detected at all. In human maternal samples, the highest concentration for PEDN was 27 ng/mL and for PEMN 150 ng/mL. In umbilical cord plasma, concentrations of 2.3 ng/mL for PEDN and 73 ng/mL for PEMN were detected. Although the PEMN and PEDN concentrations in the human samples were several times higher than in ovine samples, neither PETN nor PETriN signals could be detected. These results demonstrated that the metabolites were transferred from mother to fetus with a slight time delay.

Transplacental migration of maternal natural killer and T cells assessed by ex vivo human placenta perfusion.

INTRODUCTION: The transplacental passage of cells between a mother and her fetus, known as microchimerism, is a less studied process during pregnancy. The frequency of maternal microchimeric cells in fetal tissues in physiological pregnancies and mechanisms responsible for transplacental cell trafficking are poorly understood. This study aimed to evaluate the placental trafficking of maternal peripheral blood mononuclear cells (PBMC) using human ex vivo placenta perfusion. METHODS: Ten placentas and maternal PBMC were obtained after healthy pregnancies. Flow cytometry was used to characterize PBMC subtypes. They showed a higher percentage of CD3+ T cells compared to CD56+ NK cells. The isolated PBMC were stained with a fluorescent dye and perfused through the maternal circuit of the placenta in an ex vivo perfusion system. Subsequent immunofluorescence staining for CD3+ T cells and CD56+ NK cells was performed on placental tissue sections, and the number of detectable PBMC in different tissue areas was counted using fluorescence microscopy. RESULTS: The applied method allowed discrimination of perfused autologous maternal cells from cells resident in the placenta before perfusion. Further, it allows additional immunohistochemical labelling and distinction of immune cell subsets. Perfused PBMC were detected in all analyzed placentas, mostly in contact to the syncytiotrophoblast. CD3+ T cells were identified more frequently than CD56+ NK cells and some CD3+ T cells were found inside fetoplacental tissues and vasculature. The results indicate that also other PBMCs than T or NK cells adhere to or enter villous tissue, but they have not been specified in this analysis. DISCUSSION: Previous studies have detected maternal cells in the fetal circulation which we could mimick in our ex vivo placenta perfusion experiments with fluorescence labelled autologous maternal PBMC. The applied experimental settings did not allow comparison of transmigration abilities of PBMC subsets, but slight modifications of the model will permit further studies of cell transfer processes and microchimerism in pregnancy.

Adverse perinatal outcomes in gestational diabetes mellitus with and without SARS-CoV-2 infection during pregnancy: results from two nationwide registries in Germany.

INTRODUCTION: Pregnancy is a known independent risk factor for a severe course of COVID-19. The relationship of SARS-CoV-2 infection and gestational diabetes mellitus (GDM) on neonatal outcomes is unclear. Our aim was to determine if SARS-CoV-2 infection represents an independent risk factor for adverse perinatal outcomes in pregnancy with GDM. RESEARCH DESIGN AND METHODS: We compared data from two German registries including pregnant women with GDM, established during the SARS-CoV-2 pandemic (COVID-19-Related Obstetric and Neonatal Outcome Study (CRONOS), a multicenter prospective observational study) and already existing before the pandemic (German registry of pregnant women with GDM; GestDiab). In total, 409 participants with GDM and SARS-CoV-2 infection and 4598 participants with GDM, registered 2018-2019, were eligible for analyses. The primary fetal and neonatal outcomes were defined as: (1) combined: admission to neonatal intensive care unit, stillbirth, and/or neonatal death, and (2) preterm birth before 37+0 weeks of gestation. Large and small for gestational age, maternal insulin therapy, birth weight >4500 g and cesarean delivery were considered as secondary outcomes. RESULTS: Women with SARS-CoV-2 infection were younger (32 vs 33 years) and had a higher median body mass index (28 vs 27 kg/m²). In CRONOS, more neonates developed the primary outcome (adjusted OR (aOR) 1.48, 95% CI 1.11 to 1.97) and were born preterm (aOR 1.50, 95% CI 1.07 to 2.10). Fasting glucose was higher in women in CRONOS versus GestDiab (5.4 vs 5.3 mmol/L) considering each 0.1 mmol/L increase was independently associated with a 5% higher risk of preterm birth among women in CRONOS only (aOR 1.05, 95% CI 1.01 to 1.09). CONCLUSIONS: GDM with SARS-CoV-2 infection in pregnancy is associated with an increased risk of adverse fetal and neonatal outcomes as compared with GDM without SARS-CoV-2 infection.

SPAM-sub partual analgesia with meptazinol: a prospective cohort study comparing intramuscular with intravenous administration.

PURPOSE: Safe and effective analgesia sub partu is one of the central issues in optimizing vaginal delivery birth experiences. Meptazinol is a common opiate approved for treating labor pain in the first stage of labor. According to the manufacturer, manual meptazinol can be applied intramuscularly or intravenously. The aim of this study was to compare the two application methods in terms of efficacy in pain relief, occurrence of side effects and treatment satisfaction. METHODS: 132 patients with singleton term pregnancies and intended vaginal delivery, receiving meptazinol during first stage of labor were included in this prospective cohort study from 05/2020 to 01/2021. We evaluated effectiveness in pain relief and treatment satisfaction using numeric rating scales (NRS) and documented the occurrence of adverse effects. Chi-square test or Fisher exact test were used to compare categorical data and Mann-Whitney U test to compare continuous data between the two treatment groups. Statistical analysis was done by SPSS 27.0. A p value < 0.05 was considered to indicate statistical significance (two tailed). RESULTS: Meptazinol decreased labor pain significantly from a NRS of 8 (IQR 8-10) to 6 (IQR 4.75-8) in both treatment groups with no difference in effectiveness between the groups. Frequency of effective pain reduction of a decrease of 2 or more on the NRS did not differ between groups (39.4% vs 54.5%, p = 0.116), as the occurrence of adverse effects. 12% of the newborns were admitted to NICU, the median NApH was 7.195. CONCLUSION: Meptazinol significantly reduces labor pain regardless of the method of application: intramuscular or intravenous. According to our data, no preferable route could be identified. The comparably poorer perinatal outcome in our study cohort hinders us to confirm that meptazinol is safe and can be recommended without restrictions.

COVID-19, Pregnancy, and Diabetes Mellitus.

During the severe acute respiratory distress virus coronavirus type 2 (SARS-CoV-2) pandemic, many women were infected during their pregnancies. The SARS-CoV-2-induced coronavirus disease 19 (COVID-19) has an impact on maternal health and pregnancy outcomes; peripartum and perinatal morbidity and mortality are increased. Pregnancy is considered a risk factor for severe COVID-19 course. Additional risk factors during pregnancy are diabetes mellitus, gestational diabetes mellitus (GDM), and obesity. Systemic inflammation can lead to severe metabolic dysregulation with ketoacidosis. The endocrine pancreas is a target organ for SARS-CoV-2 and the fetal risk depends on inflammation of the placenta. Up to now there is no evidence that SARS-CoV-2 infection during pregnancy leads to permanent diabetes in mothers or their offspring via triggering autoimmunity or beta cell destruction. The frequently observed increased prevalence of GDM compared to the years before the pandemic is most likely due to changed lifestyle during lockdown. Furthermore, severe COVID-19 may be associated with the development of GDM due to worsening of glucose tolerance. Vaccination with a mRNA vaccine is safe and highly effective to prevent infection and to reduce hospitalization. Registries support offering evidence-based recommendations on vaccination for pregnant women. Even with the current omicron virus variant, there are increased risks for symptomatic and unvaccinated pregnant women.

Recommendations of the AGG (Working Group for Obstetrics, Department of Maternal Diseases) on How to Treat Thyroid Function Disorders in Pregnancy.

Objective These recommendations from the AGG (Committee for Obstetrics, Department of Maternal Diseases) on how to treat thyroid function disorder during pregnancy aim to improve the diagnosis and management of thyroid anomalies during pregnancy. Methods Based on the current literature, the task force members have developed the following recommendations and statements. These recommendations were adopted after a consensus by the members of the working group. Recommendations The following manuscript gives an insight into physiological and pathophysiological thyroid changes during pregnancy, recommendations for clinical and subclinical hypo- and hyperthyroidism, as well as fetal and neonatal diagnostic and management strategies.

Disease Perception and Mental Health in Pregnancies with Gestational Diabetes-PsychDiab Pilot Study.

(1) Background: The aim of this work is to investigate the extent to which pregnant women's well-being is burdened by the diagnosis of gestational diabetes, as well as their sensitivities and illness perceptions. Since gestational diabetes is associated with mental disorders, we hypothesized that the burden of illness might be related to pre-existing mental distress. (2) Methods: Patients treated for gestational diabetes in our outpatient clinic were retrospectively asked to complete a survey, including the self-designed Psych-Diab-Questionnaire to assess treatment satisfaction, perceived limitations in daily life and the SCL-R-90 questionnaire to assess psychological distress. The association between mental distress and well-being during treatment was analyzed. (3) Results: Of 257 patients invited to participate in the postal survey, 77 (30%) responded. Mental distress was found in 13% (n = 10) without showing other relevant baseline characteristics. Patients with abnormal SCL-R-90 scores showed higher levels of disease burden, were concerned about glucose levels as well as their child's health, and felt less comfortable during pregnancy. (4) Conclusions: Analogous to the postpartum depression screening, screening for mental health problems during pregnancy should be considered to target psychologically distressed patients. Our Psych-Diab-Questionnaire has been shown to be suitable to assess illness perception and well-being.

Obesity during Pregnancy and SARS-CoV-2/COVID-19-Case Series of the Registry Study "COVID-19 Related Obstetric and Neonatal Outcome Study" (CRONOS-Network).

(1) Background: Obesity is an increasing challenge in the care of pregnant women. The aim of our study was to investigate whether obesity is an independent risk factor for severe maternal and neonatal outcomes in pregnant women with COVID-19. (2) Methods: Data from the COVID-19 Related Obstetric and Neonatal Outcome Study (CRONOS), a prospective multicenter registry for SARS-CoV-2 positive pregnant women, was used to analyze the effect of obesity on selected individual and combined outcome parameters (3) Results: With 20.1%, the prevalence of obesity in the CRONOS registry exceeds the German background rate of 17.5%. Obese women showed significantly higher rates of GDM (20.4% vs. 7.6%; p < 0.001), hypertensive pregnancy disorders (6.2% vs. 2%; p = 0.004) and C-sections (50% vs. 34.5%; p < 0.001). BMI was revealed to be an individual risk factor for the severe combined pregnancy outcome (maternal death, stillbirth or preterm birth < 32 weeks) (OR 1.050, CI 1.005-1.097). (4) Conclusions: Maternal BMI is a predictor for the most severe outcome as maternal or neonatal death and preterm delivery <32 weeks of gestation. Unexpectedly, categorized obesity seems to have limited independent influence on the course and outcome of pregnancies with COVID infections.

Identification of altered miRNAs and their targets in placenta accreta.

Placenta accreta spectrum (PAS) is one of the major causes of maternal morbidity and mortality worldwide with increasing incidence. PAS refers to a group of pathological conditions ranging from the abnormal attachment of the placenta to the uterus wall to its perforation and, in extreme cases, invasion into surrounding organs. Among them, placenta accreta is characterized by a direct adhesion of the villi to the myometrium without invasion and remains the most common diagnosis of PAS. Here, we identify the potential regulatory miRNA and target networks contributing to placenta accreta development. Using small RNA-Seq followed by RT-PCR confirmation, altered miRNA expression, including that of members of placenta-specific miRNA clusters (e.g., C19MC and C14MC), was identified in placenta accreta samples compared to normal placental tissues. In situ hybridization (ISH) revealed expression of altered miRNAs mostly in trophoblast but also in endothelial cells and this profile was similar among all evaluated degrees of PAS. Kyoto encyclopedia of genes and genomes (KEGG) analyses showed enriched pathways dysregulated in PAS associated with cell cycle regulation, inflammation, and invasion. mRNAs of genes associated with cell cycle and inflammation were downregulated in PAS. At the protein level, NF-κB was upregulated while PTEN was downregulated in placenta accreta tissue. The identified miRNAs and their targets are associated with signaling pathways relevant to controlling trophoblast function. Therefore, this study provides miRNA:mRNA associations that could be useful for understanding PAS onset and progression.

Sonographic Flow-Mediated Dilation Imaging versus Electronic EndoCheck Flow-Mediated Slowing by VICORDER in Pregnant Women-A Comparison of Two Methods to Evaluate Vascular Function in Pregnancy.

The evaluation of endothelial function is gaining interest and importance during pregnancy, since the impaired adaptation in early pregnancy has been associated with an increased risk in preeclampsia and fetal growth restriction. To standardize the risk assessment and to implement the evaluation of vascular function in routine pregnancy care, a suitable, accurate and easy to use method is needed. Flow-mediated dilatation (FMD) of the brachial artery assessed by ultrasound is considered to be the gold standard for measuring the vascular endothelial function. The challenges of the FMD measurement have so far prevented its introduction into clinical routine. The VICORDER® device allows an automated determination of the flow-mediated slowing (FMS). The equivalence of FMD and FMS has not yet been proven in pregnant women. We collected data of 20 pregnant women randomly and consecutively while they presented for a vascular function assessment in our hospital. The gestational age at investigation was between 22 and 32 weeks of gestation, three had preexisting hypertensive pregnancy disease and three were twin pregnancies. The results for FMD or FMS below 11.3% were considered to be abnormal. Comparing FMD to FMS results in our cohort revealed a convergence in 9/9 cases, indicating normal endothelial function (specificity of 100%) and a sensitivity of 72.7%. In conclusion, we verify that the FMS measurement is a convenient, automated and operator-independent test method of endothelial function in pregnant women.

Using flash glucose monitoring in pregnancies in routine care of patients with gestational diabetes mellitus: a pilot study.

AIM: Flash glucose monitoring (FGM) has been approved for the care of pregnant women with preexisting diabetes since 2017. However, its use in gestational diabetes (GDM) has been critically discussed. Inaccuracy and missing recommendations for target values are the main arguments against the use of FGM in GDM. To date, there is a lack of data to justify routine use of FGM in GDM pregnancies. Consequently, this new technology has been withheld from GDM-patients. Aim of our pilot study was to analyze the impact of FGM use on pregnancy outcomes, patient's satisfaction and to confirm the safe use in GDM pregnancies. METHODS: Cohort study of 37 FGM-managed GDM pregnancies compared with 74 matched women using self-monitoring of blood glucose (SMBG). Group comparison using nonparametric testing concerning patients characteristic and perinatal outcome focusing on adverse outcomes (preeclampsia, preterm delivery, large for gestational age, C-sections, neonatal intensive care unit admission, hyperbilirubinemia and hypoglycemia). Evaluation of patient's treatment satisfaction using the "Diabetes Treatment Satisfaction Questionnaire change" (DTSQc) and patient interviews. RESULTS: No significant differences in patient's characteristics despite gestational age at diagnosis (FGM with 20 vs. SMBG with 25 weeks). No difference in gestational weight gain, HbA1c progression and perinatal outcome. Treatment satisfaction obtained by the DTSQc revealed a high level of satisfaction with FGM use. CONCLUSION: FGM use was well accepted and did not affect perinatal outcome. Use of FGM during pregnancy is safe and non-inferior to the management with SBGM. FGM should be considered as an option in the management of GDM patients.

[SARS-CoV-2/COVID-19 and Hypertensive Pregnancy Disorders: Evaluation of the CRONOS National Registry]. / Hypertensive Schwangerschaftserkrankungen und SARS-CoV-2/COVID-19: Auswertung des nationalen CRONOS-Registers.

SARS-CoV-2 infection and COVID-19 disease are associated with an increased risk of hypertensive pregnancy disease in international registry studies. Preexisting hypertensive disorders are recognized as a risk factor of severe COVID-19 progression in pregnancy. The respective damage to the endothelium is discussed as a pathophysiological commonality of both diseases.Data of the national CRONOS registry (data status 05/2021; 1104 pregnant women with SARS-CoV-2 infection) were analyzed regarding the association of hypertensive pregnancy disease and maternal, pregnancy, neonatal, and COVID-19 disease outcomes. In the presence of hypertensive pregnancy disease, a severe combined outcome of pregnancy (17.3 vs. 4.3%, p=0.001), mother (25.0 vs. 9.4%, p=0.001), and newborn (28.8 vs. 9.1%, p<0.0005) occurred significantly more frequent. In contrast, the outcome of COVID-19 disease did not differ (3.8 vs. 7.5%, p=0.424). The co-occurrence of SARS-CoV-2 infection and hypertensive pregnancy disease should be acknowledged as risk factor during management decisions.

Effect of pentaerythritol tetranitrate (PETN) on the development of fetal growth restriction in pregnancies with impaired uteroplacental perfusion at midgestation-a randomized trial.

BACKGROUND: Fetal growth restriction is strongly associated with impaired placentation and abnormal uteroplacental blood flow. Nitric oxide donors such as pentaerythritol tetranitrate are strong vasodilators and protect the endothelium. Recently, we demonstrated in a randomized controlled pilot study a 38% relative risk reduction for the development of fetal growth restriction or perinatal death following administration of pentaerythritol tetranitrate to pregnant women at risk, identified by impaired uterine perfusion at midgestation. Results of this monocenter study prompted the hypothesis that pentaerythritol tetranitrate might have an effect in pregnancies with compromised placental function as a secondary prophylaxis. OBJECTIVE: This study aimed to test the hypothesis that the nitric oxide donor pentaerythritol tetranitrate reduces fetal growth restriction and perinatal death in pregnant women with impaired placental perfusion at midgestation in a multicenter trial. STUDY DESIGN: In this multicenter, randomized, double-blind, placebo-controlled trial, 2 parallel groups of pregnant women presenting with a mean uterine artery pulsatility index >95th percentile at 19+0 to 22+6 weeks of gestation were randomized to 50-mg Pentalong or placebo twice daily. Participants were assigned to high- or low-risk groups according to their medical history before randomization was performed block-wise with a fixed block length stratified by center and risk group. The primary efficacy endpoint was the composite outcome of perinatal death or development of fetal growth restriction. Secondary endpoints were neonatal and maternal outcome parameters. RESULTS: Between August 2017 and March 2020, 317 participants were included in the study and 307 were analyzed. The cumulative incidence of the primary outcome was 41.1% in the pentaerythritol tetranitrate group and 45.5% in the placebo group (unadjusted relative risk, 0.90; 95% confidence interval, 0.69-1.17; adjusted relative risk, 0.90; 95% confidence interval, 0.69-1.17; P=.43). Secondary outcomes such as preterm birth (unadjusted relative risk, 0.73; 95% confidence interval, 0.56-0.94; adjusted relative risk, 0.73; 95% confidence interval, 0.56-0.94; P=.01) and pregnancy-induced hypertension (unadjusted relative risk, 0.65; 95% confidence interval, 0.46-0.93; adjusted relative risk, 0.65; 95% confidence interval, 0.46-0.92; P=0.01) were reduced. CONCLUSION: Our study failed to show an impact of pentaerythritol tetranitrate on the development of fetal growth restriction and perinatal death in pregnant women with impaired uterine perfusion at midgestation. Pentaerythritol tetranitrate significantly reduced secondary outcome parameters such as the incidence of preterm birth and pregnancy-induced hypertension in these pregnancies.

Ex vivo perfusion of the human placenta to investigate pregnancy pathologies.

Pregnancy pathologies including gestational diabetes, intrauterine fetal growth restriction, and pre-eclampsia are common and significantly increase the risk of poor pregnancy outcomes. Research to better understand the pathophysiology and improve diagnosis and treatment is therefore crucial. The ex vivo placenta perfusion model offers a unique system to study pregnancy pathology without the risk of harm to mother or fetus. The presence of a maternal and fetal circulation and intact villus tree, facilitates investigations into maternal-fetal transfer, altered hemodynamics and vascular reactivity in the human placenta. It also provides a platform to test novel therapeutic agents. Here we review the key studies which have utilized the ex vivo placenta perfusion model to study different aspects of such pregnancy pathologies.