Delayed cord clamping in small for gestational age preterm infants

The inhibition of placental mTOR signaling leads to fetal growth restriction with abnormal glucose metabolism in different anatomical regions of placentas

INTRODUCTION

Fetal growth restriction (FGR) is a common pregnancy complication with significant impact on obstetric and birth outcomes. Increasing evidence shows that the inhibition of placental mechanistic target of rapamycin (mTOR) signaling is closely related to FGR. However, the pathogenesis of FGR is not fully consistent presently, which is subject to the methodological divergence.

METHODS

Rapamycin was used to construct the FGR mouse model. Hematoxylin & eosin (HE) and periodic acid-schiff (PAS) staining were used to analyze the morphology of mouse placenta. Western blot was used to analyze the expression levels of glucose transporters and key enzymes associated with glycogen metabolism in human/mouse placental tissues in different anatomic layers. HTR-8 cells were treated with dimethyl sulfoxide (DMSO) or rapamycin (2 mM) for 24 h. Cell viability was detected by CCK8 kit. In addition, glycogen concentration in placental tissue or cell samples was detected by Glycogen Assay Kit.

RESULTS

Firstly, we observed a significant reduction of glucose content in different anatomical regions of human small-for-gestational-age (SGA) placenta, also glucose metabolism was undermined to some extent. Then, we found that FGR placentas showed abnormal morphological changes, the glycogen levels in FGR placentas were significantly reduced by quantitative detection. Meanwhile, the expression levels of glucose transporters, Gys1 and p-Gsk3β in FGR placentas were reduced compared to controls. The HTR-8 cells treated with rapamycin revealed decreasing mTOR activity and glycogen levels. In addition, glucose transporter, GYS1, p-GSK3β expressions were all significantly reduced and t-GSK3β level was significantly elevated.

DISCUSSION

Overall, our data indicate that inhibition of placental mTOR signaling may contribute to the occurrence of FGR by altering glucose metabolism.

Effect of Paternal Body Mass Index on In Vitro Fertilization and Neonatal Outcomes among Oligozoospermia and Asthenospermia Patients

PURPOSE

Male overweight and obesity could affect sperm quality and reproductive health. However, the impact of body mass index (BMI) on assisted reproductive technology (ART) outcomes in oligospermia and/or asthenospermia patients is yet lacking. This study aims to assess the impact of paternal BMI on ART and neonatal outcomes among oligozoospermia and/or asthenospermia patients undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

MATERIALS AND METHODS

In this study, 2,075 couples undergoing their first fresh embryo transfer between January 2015 and June 2022 were recruited. Following the World Health Organization's (WHO's) categories, couples were stratified into three cohorts based on paternal BMI: normal weight (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²), and obese (≥30.0 kg/m²). Modified Poisson regression models were used to assess the associations of paternal BMI with fertilization, in vitro embryonic development, and pregnancy outcomes. Logistic regression models were performed to investigate the associations of paternal BMI with pregnancy loss and neonatal outcomes. Furthermore, stratified analyses were performed based on fertilization methods, male infertility cause, and maternal BMI.

RESULTS

Higher paternal BMI is associated with a lower likelihood of achieving normal fertilized (p-trend=0.002), Day 3 transferable (p-trend=0.007), and high-quality embryos (p-trend=0.046) in IVF cycles, rather than in ICSI cycles. Paternal BMI of oligospermia or asthenospermia was negatively correlated with day 3 transferable (p-trend=0.013 and 0.030) and high-quality embryos (p-trend=0.024 and 0.027). Moreover, for neonatal outcomes, paternal BMI was positively associated with macrosomia (p-trend=0.019), large for gestational age (LGA) (p-trend=0.031), and very LGA (p-trend=0.045).

CONCLUSIONS

Our data suggested that higher paternal BMI was associated with fetal overgrowth, reduced fertilization, and embryonic development potential. Among males with oligospermia and/or asthenospermia, the impact of overweight and obesity on the choice of fertilization method and the long-term effects on their offspring need to be further investigated.

Directive clinique no 442 : Retard de croissance intra-utérin : Dépistage, diagnostic et prise en charge en contexte de grossesse monofœtale

OBJECTIF

Le retard de croissance intra-utérin est une complication obstétricale fréquente qui touche jusqu'à 10 % des grossesses dans la population générale et qui est le plus souvent due à une pathologie placentaire sous-jacente. L'objectif de la présente directive clinique est de fournir des déclarations sommaires et des recommandations pour appuyer un protocole clinique de dépistage, diagnostic et prise en charge du retard de croissance intra-utérin pour les grossesses à risque ou atteintes.

POPULATION CIBLE

Toutes les patientes enceintes menant une grossesse monofœtale. BéNéFICES, RISQUES ET COûTS: La mise en application des recommandations de la présente directive devrait améliorer la compétence des cliniciens quant à la détection du retard de croissance intra-utérin et à la réalisation des interventions indiquées. DONNéES PROBANTES: La littérature publiée a été colligée par des recherches effectuées jusqu'en septembre 2022 dans les bases de données PubMed, Medline, CINAHL et Cochrane Library en utilisant un vocabulaire contrôlé au moyen de termes MeSH pertinents (fetal growth retardation and small for gestational age) et de mots-clés (fetal growth, restriction, growth retardation, IUGR, FGR, low birth weight, small for gestational age, Doppler, placenta, pathology). Seuls les résultats de revues systématiques, d'essais cliniques randomisés ou comparatifs et d'études observationnelles ont été retenus. La littérature grise a été obtenue par des recherches menées dans des sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, des registres d'essais cliniques et des sites Web de sociétés de spécialité médicale nationales et internationales. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations Assessment, Development and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et conditionnelles [faibles]). PROFESSIONNELS CONCERNéS: Obstétriciens, médecins de famille, infirmières, sages-femmes, spécialistes en médecine fœto-maternelle, radiologistes et autres professionnels de la santé qui prodiguent des soins aux patientes enceintes. RéSUMé POUR TWITTER: Mise à jour de la directive sur le dépistage, le diagnostic et la prise en charge du retard de croissance intra-utérin pour les grossesses à risque ou atteintes. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS: Prédiction du retard de croissance intra-utérin Prévention du retard de croissance intra-utérin Détection du retard de croissance intra-utérin Examens en cas de retard de croissance intra-utérin soupçonné Prise en charge du retard de croissance intra-utérin précoce Prise en charge du retard de croissance intra-utérin tardif Prise en charge du post-partum et consultations préconception.

Guideline No. 442: Fetal Growth Restriction: Screening, Diagnosis, and Management in Singleton Pregnancies

OBJECTIVE

Fetal growth restriction is a common obstetrical complication that affects up to 10% of pregnancies in the general population and is most commonly due to underlying placental diseases. The purpose of this guideline is to provide summary statements and recommendations to support a clinical framework for effective screening, diagnosis, and management of pregnancies that are either at risk of or affected by fetal growth restriction.

TARGET POPULATION

All pregnant patients with a singleton pregnancy.

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in this guideline should increase clinician competency to detect fetal growth restriction and provide appropriate interventions.

EVIDENCE

Published literature in English was retrieved through searches of PubMed or MEDLINE, CINAHL, and The Cochrane Library through to September 2022 using appropriate controlled vocabulary via MeSH terms (fetal growth retardation and small for gestational age) and key words (fetal growth, restriction, growth retardation, IUGR, FGR, low birth weight, small for gestational age, Doppler, placenta, pathology). Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. Grey literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Table A1 for definitions and Table A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

Obstetricians, family physicians, nurses, midwives, maternal-fetal medicine specialists, radiologists, and other health care providers who care for pregnant patients.

TWEETABLE ABSTRACT

Updated guidelines on screening, diagnosis, and management of pregnancies at risk of or affected by FGR.

SUMMARY STATEMENTS

RECOMMENDATIONS: Prediction of FGR Prevention of FGR Detection of FGR Investigations in Pregnancies with Suspected Fetal Growth Restriction Management of Early-Onset Fetal Growth Restriction Management of Late-Onset FGR Postpartum management and preconception counselling.

Effects of umbilical cord milking versus delayed cord clamping on systemic blood flow in intrauterine growth-restricted neonates: A randomized controlled trial

Recommendations for umbilical cord management in intrauterine growth-restricted (IUGR) neonates are lacking. The present randomized controlled trial compared hemodynamic effects of umbilical cord milking (UCM) with delayed cord clamping (DCC) in IUGR neonates > 28 weeks of gestation, not requiring resuscitation. One hundred seventy IUGR neonates were randomly allocated to intact UCM (4 times squeezing of 20 cm intact cord; n = 85) or DCC (cord clamping after 60 s; n = 85) immediately after delivery. The primary outcome variable was superior vena cava (SVC) blood flow at 24 ± 2 h. Secondary outcomes assessed were anterior cerebral artery (ACA) and superior mesenteric artery (SMA) blood flow indices, right ventricular output (RVO), regional cerebral oxygen saturation (CrSO2) and venous hematocrit at 24 ± 2 h, peak total serum bilirubin (TSB), incidences of in-hospital complications, need and duration of respiratory support, and hospital stay. SVC flow was significantly higher in UCM compared to DCC (111.95 ± 33.54 and 99.49 ± 31.96 mL/kg/min, in UCM and DCC groups, respectively; p < 0.05). RVO and ACA/SMA blood flow indices were comparable whereas CrSO2 was significantly higher in UCM group. Incidences of polycythemia and jaundice requiring phototherapy were similar despite significantly higher venous hematocrit and peak TSB in UCM group. The need for non-invasive respiratory support was significantly higher in UCM group though the need and duration of mechanical ventilation and other outcomes were comparable.

CONCLUSIONS

 UCM significantly increases SVC flow, venous hematocrit, and CrSO2 compared to DCC in IUGR neonates without any difference in other hemodynamic parameters and incidences of polycythemia and jaundice requiring phototherapy; however, the need for non-invasive respiratory support was higher with UCM.

TRIAL REGISTRATION

Clinical trial registry of India (CTRI/2021/03/031864).

WHAT IS KNOWN

• Umbilical cord milking (UCM) increases superior vena cava blood flow (SVC flow) and hematocrit without increasing the risk of symptomatic polycythemia and jaundice requiring phototherapy in preterm neonates compared to delayed cord clamping (DCC). • An association between UCM and intraventricular hemorrhage in preterm neonates < 28 weeks of gestation is still being investigated.

WHAT IS NEW

• Placental transfusion by UCM compared to DCC increases SVC flow, regional cerebral oxygenation, and hematocrit without increasing the incidence of symptomatic polycythemia and jaundice requiring phototherapy in intrauterine growth-restricted neonates. • UCM also increases the need for non-invasive respiratory support compared to DCC.

Toward greater nuance in delayed cord clamping

PURPOSE OF REVIEW

For over a decade, the International Liaison Committee on Resuscitation has recommended delayed cord clamping (DCC), but implementation has been variable due to lack of consensus on details of technique and concerns for risks in certain patient populations. This review summarizes recent literature on the benefits and risks of DCC in term and preterm infants and examines alternative approaches such as physiologic-based cord clamping or intact cord resuscitation (ICR) and umbilical cord milking (UCM).

RECENT FINDINGS

DCC improves hemoglobin/hematocrit among term infants and may promote improved neurodevelopment. In preterms, DCC improves survival compared to early cord clamping; however, UCM has been associated with severe intraventricular hemorrhage in extremely preterm infants. Infants of COVID-19 positive mothers, growth-restricted babies, multiples, and some infants with cardiopulmonary anomalies can also benefit from DCC. Large randomized trials of ICR will clarify safety and benefits in nonvigorous neonates. These have the potential to dramatically change the sequence of events during neonatal resuscitation.

SUMMARY

Umbilical cord management has moved beyond simple time-based comparisons to nuances of technique and application in vulnerable sub-populations. Ongoing research highlights the importance of an individualized approach that recognizes the physiologic equilibrium when ventilation is established before cord clamping.