Successful management of fetal hypoxia due to amniotic banding at 26 weeks of pregnancy: A case report of a rare survival.

BACKGROUND: Amniotic banding is a rare condition that can lead to structural limb anomalies, fetal distress and adverse obstetric outcomes. The main hypothesis for its etiology is a rupture of the amniotic membrane in early pregnancy, with the formation of tightly entangling strands around the fetus. These strands can constrict, incise, and subsequently amputate limb parts, the neck or head. More rarely, the amniotic banding can affect the umbilical cord, leading to fetal distress or potential intra-uterine fetal demise. OBJECTIVE: We present a unique case of a 26-week pregnant woman who attended a polyclinical consultation due to reduced fetal movements with concerning cardiotocography (CTG) findings. A review of the literature about amniotic banding of the umbilical cord was conducted as well, identifying diagnostic and interventional options for the obstetrician's practice. STUDY DESIGN: This is a case report, alongside a review of the literature. RESULTS: The CTG indicated fetal distress, prompting an emergency caesarean section (C-section). Upon delivery, the neonate exhibited signs of amniotic band sequence, with distal phalangeal defects on the right hand and severe constriction of the umbilical cord caused by amniotic strands, the latter precipitating fetal hypoxia. Direct ultrasound diagnosis remains a challenge in the absence of limb amputation, yet indirect signs such as distal limb or umbilical doppler flow abnormalities and distal limb edema may be suggestive of amniotic banding. MRI is proposed as an adjuvant diagnostic tool yet does not present a higher detection rate compared to ultrasound. Fetoscopic surgery to perform lysis of the amniotic strands with favorable outcome has been described in literature. CONCLUSION: This case presents the first reported survival of an extremely preterm fetus in hypoxic distress as a cause of amniotic banding of the umbilical cord, with a rare degree of incidental timing. Ultrasound diagnosis remains the gold standard. Obstetrical vigilance is warranted, with fetal rescue proven to be feasible.

Chronic hypoxia in pregnant mice impairs the placental and fetal vascular response to acute hypercapnia in BOLD-MRI hemodynamic response imaging.

INTRODUCTION: Brief hypercapnic challenge causes acute placental hypoperfusion with fetal brain sparing on BOLD-MRI. We hypothesize that this non-invasive imaging strategy can distinguish between normal pregnancy and chronic placental hypoperfusion (using the maternal hypoxia model). METHODS: Eighteen pregnant female ICR mice were randomized to three groups: normoxia, late-onset hypoxia (12%O2;E13.5-17.5) and early-onset hypoxia (12%O2;E10.5-17.5). On E17.5, animals were imaged in a 4.7-T Bruker-Biospec MRI scanner. Fast coronal True-FISP was performed to identify organs of interest (placenta and fetal heart, liver and brain). BOLD-MRI was performed at baseline and during a 4-min hypercapnic challenge (5%CO2). %-change in placental and fetal signal was analyzed from T2*-weighted gradient echo MR images. Following MRI, fetuses and placentas were harvested, weighed and immuno-stained. RESULTS: In normoxic mice, hypercapnia caused reduction in BOLD-MRI signal in placenta (-44% ± 7%; p < 0.0001), fetal liver (-32% ± 7%; p < 0.0001) and fetal heart (-54% ± 12%; p < 0.002), with relative fetal brain sparing (-12% ± 5%; p < 0.0001). These changes were markedly attenuated in both hypoxia groups. Baseline fetal brain/placenta SI ratio was highest in normoxic mice (1.14 ± 0.017) and reduced with increasing duration of hypoxia (late-onset hypoxia: 1.00 ± 0.026; early-onset hypoxia: 0.91 ± 0.016; p = 0.02). Both hypoxic groups exhibited fetal growth restriction with prominent placental glycogen-containing cells, particularly in early-onset hypoxia. There was increased fetal neuro- and intestinal-apoptosis in early-onset hypoxia only. CONCLUSIONS: BOLD-MRI with brief hypercapnic challenge distinguished between normoxia and both hypoxia groups, while fetal neuroapoptosis was only observed after early-onset hypoxia. This suggests that BOLD-MRI with hypercapnic challenge can identify chronic fetal asphyxia before the onset of irreversible brain injury.

Maternal and fetal effects of COVID-19 virus on a complicated triplet pregnancy: a case report.

BACKGROUND: Coronavirus disease 2019 (COVID-19), the global pandemic that has spread throughout the world, is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Given the limited scientific evidence on the manifestations and potential impact of this virus on pregnancy, we decided to report this case. CASE PRESENTATION: The patient was a 38 year-old Iranian woman with a triplet pregnancy and a history of primary infertility, as well as hypothyroidism and gestational diabetes. She was hospitalized at 29 weeks and 2 days gestational age due to elevated liver enzymes, and finally, based on a probable diagnosis of gestational cholestasis, she was treated with ursodeoxycholic acid. On the first day of hospitalization, sonography was performed, which showed that biophysical scores and amniotic fluid were normal in all three fetuses, with normal Doppler findings in two fetuses and increased umbilical artery resistance (pulsatility index [PI] > 95%) in one fetus. On day 4 of hospitalization, she developed fever, cough and myalgia, and her COVID-19 test was positive. Despite mild maternal symptoms, exacerbated placental insufficiency occurred in two of the fetuses leading to the rapid development of absent umbilical artery end-diastolic flow. Finally, 6 days later, the patient underwent cesarean section due to rapid exacerbation of placental insufficiency and declining biophysical score in two of the fetuses. Nasopharyngeal swab COVID-19 tests were negative for the first and third babies and positive for the second baby. The first and third babies died 3 and 13 days after birth, respectively, due to collapsed white lung and sepsis. The second baby was discharged in good general condition. The mother was discharged 3 days after cesarean section. She had no fever at the time of discharge and was also in good general condition. CONCLUSIONS: This was a complicated triplet pregnancy, in which, after maternal infection with COVID-19, despite mild maternal symptoms, exacerbated placental insufficiency occurred in two of the fetuses, and the third fetus had a positive COVID-19 test after birth. Therefore, in cases of pregnancy with COVID-19 infection, in addition to managing the mother, it seems that physicians would be wise to also give special attention to the possibility of acute placental insufficiency and subsequent fetal hypoxia, and also the probability of vertical transmission.

Cardiac Doppler in poorly controlled gestational diabetics and its link to markers of intra-uterine hypoxia and adverse outcome.

The aim of the study was to investigate foetal cardiac function using the modified myocardial performance index (Mod-MPI) in poorly controlled gestational diabetics and its link with intrauterine markers for hypoxia and to an adverse outcome. In a prospective, cross sectional study, 44 consecutive women with severe or poorly controlled gestational diabetic pregnancies in their third trimester on insulin therapy were recruited and matched with 44 women with normal pregnancies which served as the control group. Using Doppler echocardiography the foetal Mod-MPI was calculated. The foetal Mod-MPI was significantly higher in the diabetic group compared to the controls indicating significant myocardial dysfunction. The Mod-MPI served as an excellent marker of adverse outcomes. Foetal myocardial function was significantly impaired in poorly controlled gestational diabetics and there was a significant link of Mod-MPI to intrauterine markers of hypoxia, as well as to an adverse outcome. Mod-MPI has the potential to improve foetal surveillance in gestational diabetes.IMPACT STATEMENTWhat is already known on this subject? Abnormal foetal cardiac function, as reflected in the modified myocardial performance index, has been reported to be significantly increased in foetuses of poorly controlled diabetics managed on insulin.What do the results of this study add? There is a significant link between abnormal foetal cardiac function to intrauterine markers of hypoxia, as well as to an adverse outcome; and that development of myocardial dysfunction could be one of the main mechanisms, inducing foetal compromise in poorly controlled gestational diabetes.What are the implications of these findings for clinical practice and/or further research? This study explores an interesting concept of foetal pathophysiology in gestational diabetes, namely the concept of "pseudo-hypoxia" in a foetus of a gestational diabetic mother, and this intrauterine "hypoxic stress" in turn leading to myocardial dysfunction. The Mod-MPI, a clinical marker for cardiac dysfunction, can therefore be used in the clinical setting to track a deteriorating metabolic state.

Interpretation of Fetal Heart Rate Monitoring in the Clinical Context.

Use of intrapartum fetal heart rate (FHR) monitoring has had limited success in preventing hypoxic injury to neonates. One of the most common limitations of FHR interpretation is the failure to consider chronic and acute clinical factors that may increase the risk of evolving acidemia. This manuscript reviews common clinical factors that may affect the FHR and should be considered when determining the need for early intervention based on changes in the FHR.

Interventions for Intrapartum Fetal Heart Rate Abnormalities.

Intrapartum fetal heart rate (FHR) decelerations may represent interrupted oxygen transfer to the fetus. In many cases, these interruptions are transient and do not result in progressive fetal acidemia with risk for asphyxia and neurological compromise. When significant FHR decelerations are present, reversible causes of reduced fetal oxygen delivery should be considered and corrective measures should be undertaken to optimize oxygenation. In this review, we describe potential intrapartum causes of reduced fetal oxygen delivery and the efficacy of common interventions for an abnormal FHR tracing.

Physiology of Fetal Heart Rate Monitoring.

Fetal heart tracings (FHTs) are useful as a window into the oxygenation status of the fetal brain. Patterns in the FHT reflect the oxygen status of the fetal brain. Fetal adaptive response to progressive hypoxemia and acidosis are detectable and produce recognizable patterns in the fetal heart rate. The basic physiology and adaptive responses that regulate the fetal heart rate and physiological fetal adaptations to stress as reflected in the FHTs are described. Mechanisms of oxygen delivery to the fetus including ways in which those mechanisms can be disrupted are reviewed.

The newborn sheep translational model for pulmonary arterial hypertension of the neonate at high altitude.

Chronic hypoxia during gestation induces greater occurrence of perinatal complications such as intrauterine growth restriction, fetal hypoxia, newborn asphyxia, and respiratory distress, among others. This condition may also cause a failure in the transition of the fetal to neonatal circulation, inducing pulmonary arterial hypertension of the neonate (PAHN), a syndrome that involves pulmonary vascular dysfunction, increased vasoconstrictor tone and pathological remodeling. As this syndrome has a relatively low prevalence in lowlands (~7 per 1000 live births) and very little is known about its prevalence and clinical evolution in highlands (above 2500 meters), our understanding is very limited. Therefore, studies on appropriate animal models have been crucial to comprehend the mechanisms underlying this pathology. Considering the strengths and weaknesses of any animal model of human disease is fundamental to achieve an effective and meaningful translation to clinical practice. The sheep model has been used to study the normal and abnormal cardiovascular development of the fetus and the neonate for almost a century. The aim of this review is to highlight the advances in our knowledge on the programming of cardiopulmonary function with the use of high-altitude newborn sheep as a translational model of PAHN.

Identification of the Fetus at Risk for Metabolic Acidemia Using Continuous Fetal Heart Rate Monitoring.

The fetal heart rate can be used to assess the current metabolic state of the fetus and predict the risk of the evolution of metabolic acidemia through the course of labor. In this chapter, we will present the pathophysiology of the development of fetal acidemia and provide an organized approach to identifying the risk of worsening acidemia using changes noted in the fetal heart rate pattern to allow for interventions that might alter this course.

Is obesity in pregnancy associated with signs of chronic fetal hypoxia?

INTRODUCTION: The prevalence of obesity in pregnancy is increasing worldwide. Maternal obesity increases risks of severe fetal and neonatal complications. The underlying pathophysiological mechanisms are unclear. One possible contributing factor could be chronic fetal hypoxia. The aim of this study was to compare placentas from women with and without obesity with respect to placental lesions, which could reflect compensatory mechanisms in response to chronic fetal hypoxia as well as lesions possibly leading to chronic fetal hypoxia. In addition, levels of erythropoietin in cord blood were compared between offspring of lean and obese women. MATERIAL AND METHODS: This cohort study included 180 women with uneventful, full-term, singleton pregnancies, out of which 91 lean women had a body mass index (BMI) of 18.5-24.9 kg/m2 and 89 women had obesity (BMI ≥30 kg/m2 ). Women were recruited at Södersjukhuset between 16 October 2018 and 2 December 2019. Placentas were investigated by two senior perinatal pathologists, who were blinded for maternal BMI. Cord blood was analyzed for levels of erythropoietin. RESULTS: Levels of erythropoietin in cord blood increased with maternal BMI (P = .01, ß = 0.97, 95% CI 0.27-1.68). There was no difference between placentas of obese and lean women in number of placental lesions reflecting chronic fetal hypoxia or in lesions that could possibly lead to chronic fetal hypoxia. CONCLUSIONS: This study of term and uneventful pregnancies demonstrated a positive association between maternal obesity and concentrations of erythropoietin in cord blood at birth. This finding supports the hypothesis of chronic fetal hypoxia as a risk factor for complications in the pregnancies of obese women. There were no differences in lesions associated with hypoxia between placentas of obese and lean women.

Fetal Bradycardia in Response to Maternal Hypothermia.

BACKGROUND: Fetal tachycardia can occur with maternal fever (hyperthermia); therefore, a low maternal temperature (hypothermia) might produce fetal bradycardia. CASES: Five cases of fetal bradycardia are presented in gestations complicated by maternal hypothermia. The fetal heart rate (FHR) tracings demonstrated stable baselines of 88-96 beats per minute with moderate variability and accelerations. All baselines returned to normal after maternal warming measures. CONCLUSION: A possible cause for fetal bradycardia with a stable baseline and moderate variability is maternal hypothermia, a pattern not indicative of fetal hypoxia. Delivery is not indicated, and maternal warming results in FHR baseline normalization.

Fetal cardiovascular response to acute hypoxia during maternal anesthesia.

Preclinical imaging studies of fetal hemodynamics require anesthesia to immobilize the animal. This may induce cardiovascular depression and confound measures under investigation. We compared the impact of four anesthetic regimes upon maternal and fetal blood gas and hemodynamics during baseline periods of normoxia, and in response to an acute hypoxic challenge in pregnant sheep. Merino ewes were surgically prepared with maternal and fetal vascular catheters and a fetal femoral artery flow probe at 105-109 days gestation. At 110-120 days gestation, ewes were anesthetized with either isoflurane (1.6%), isoflurane (0.8%) plus ketamine (3.6 mg·kg-1 ·h-1 ), ketamine (12.6 mg·kg-1 ·h-1 ) plus midazolam (0.78 mg·kg-1 ·h-1 ), propofol (30 mg·kg-1 ·h-1 ), or remained conscious. Following 60 min of baseline recording, nitrogen was administered directly into the maternal trachea to displace oxygen and induce maternal and thus fetal hypoxemia. During normoxia, maternal PaO2 was ~30 mmHg lower in anesthetized ewes compared to conscious controls, regardless of the type of anesthesia (p < .001). There was no effect of anesthesia on fetal mean arterial blood pressure (MAP; p > .05), but heart rate was 32 ± 8 bpm lower in fetuses from ewes administered isoflurane (p = .044). During maternal hypoxia, fetal MAP increased, and peripheral blood flow decreased in all fetuses except those administered propofol (p < .05). Unexpectedly, hypoxemia also induced fetal tachycardia regardless of the anesthetic regime (p < .05). These results indicate that despite maternal anesthesia, the fetus can mount a cardiovascular response to acute hypoxia by increasing blood pressure and reducing peripheral blood flow, although the heart rate response may differ from when no anesthesia is present.

Ex Utero Extracorporeal Support as a Model for Fetal Hypoxia and Brain Dysmaturity.

BACKGROUND: Congenital heart disease (CHD) is associated with abnormal fetal brain development, a phenomenon that may be related to decreased cerebral oxygen delivery in utero. We used an artificial womb model to test the hypothesis that decreasing fetal oxygen delivery would reproduce physiologic changes identified in fetuses with CHD. METHODS: Experimental (hypoxemic) fetal lambs (mean gestational age, 111 ± 3 days; n = 4) and control animals (112 days; n = 5) were maintained in the artificial womb for a mean of 22 ± 6 days. Oxygen delivery was reduced to 15.6 ± 1.0 mL/kg/min in the hypoxemia animals versus 21.6 ± 2.0 mL/kg/min in the control animals. Blood chemistry analysis and sonographic evaluation were performed daily. An additional control group (n = 7) was maintained in utero and harvested for analysis at gestational age 134 ± 4 days. RESULTS: Physiologic variables were monitored continuously, and no statistical differences between the groups were identified. Fetal oxygen delivery and arterial partial pressure of oxygen were remarkably lower in the experimental group longitudinally. Increased umbilical artery and decreased middle cerebral artery resistance resulted in a lower cerebral to umbilical resistance ratio, similar to the brain sparing effect observed in human fetuses with CHD. Experimental brains were smaller than control brains in relation to the calvarium on magnetic resonance. CONCLUSIONS: Sustained hypoxemia in fetal sheep leads to altered cerebrovascular resistances and loss of brain mass, similar to human fetuses with CHD. This unique model provides opportunities to investigate the pathologic process underlying CHD-associated brain dysmaturity and to evaluate potential fetal neuroprotective therapies.

Effects of Vasoactive Medications and Maternal Positioning During Cesarean Delivery on Maternal Hemodynamics and Neonatal Acid-Base Status.

Maternal hemodynamics, positioning, and anesthesia technique for cesarean delivery influence neonatal acid-base balance; direct effects from drugs that cross the placenta also have an influence. Spinal anesthesia limits fetal exposure to depressant drugs and avoids maternal airway instrumentation, but is associated with hypotension. Hypotension may be prevented/treated with vasopressors and intravenous fluids. Current evidence supports phenylephrine as the first-line vasopressor. Fifteen degrees of lateral tilt during cesarean delivery has been advocated to relieve vena caval obstruction, but routine use may be unnecessary in healthy nonobese women having elective cesarean delivery if maternal blood pressure is maintained near baseline.

Disrupted compensatory response mediated by Wolfram syndrome 1 protein and corticotrophin-releasing hormone family peptides in early-onset intrahepatic cholestasis pregnancy.

INTRODUCTION: The most adverse perinatal outcome of intrahepatic cholestasis of pregnancy (ICP) is sudden fetal death related to acute fetoplacental hypoxia. Corticotrophin-releasing hormone (CRH), urocortin (UCN), and Wolfram syndrome 1 (WFS1) proteins may have a compensatory response to hypoxic stress. METHODS: A total of 108 singleton pregnant women were divided into three groups: control, late-onset ICP, and early-onset ICP. Enzyme-linked immunosorbent assays were used to detected maternal serum CRH, UCN, and WFS1 levels. Western blotting and real-time polymerase chain reaction were conducted to quantify placental protein and mRNA levels of CRH, UCN, and WFS1. Pearson correlation scatterplots and Pearson correlation matrix were employed to testify the correlation. RESULTS: Placental WFS1 had a positive relation with placental UCN (r = 0.69, P < 0.05) and serum UCN (r = 0.36, P < 0.05). Placental CRH was positively correlated with maternal serum CRH (r = 0.53, P < 0.05). Maternal serum and placental levels of CRH, UCN, and WFS1 significantly increased in the early-onset ICP group compared with the control group (P < 0.05). Placental levels of UCN and WFS1 in the early-onset ICP group were significantly elevated and higher in comparison with the late-onset ICP group (P < 0.05). However, the transcriptional levels of CRH, UCN, and WFS1 were impaired in the early-onset ICP group. DISCUSSION: Our study revealed that transcription and translation of WFS1, CRH, and UCN were altered during pregnancies complicated by early-onset ICP. This disrupted compensatory response mediated by WFS1 and CRH family peptides in early-onset ICP may play a significant role in the pathogenesis of sudden fetal death in acute fetal hypoxia.

Significance of assay of nucleated RBCs in umbilical cord blood in neonates with meconium-stained amniotic fluid.

BACKGROUND: Approximately 8-15% of all infants are born with evidence of meconium-stained amniotic fluid (MSAF). MSAF is a potentially serious sign of fetal compromise and may indicate fetal hypoxia Objectives and aim of the work: The present study was designed to evaluate the relationship between meconium stained amniotic fluid and fetal nucleated red blood cell counts. As well, we aim to evaluate the relationship between the presence of meconium in amniotic fluid and Apgar scores in neonates. SUBJECTS AND METHODS: A prospectively case-controlled study was performed on 40 women with clear amniotic fluid as control and 40 women with meconium-stained amniotic fluid as the study group. At delivery, 2 ml of umbilical cord blood was collected and analyzed for nucleated red blood cell (NRBC). RESULTS: The mean NRBC counts in meconium-stained amniotic fluid was significantly higher than the control group (18.35 ± 7.7 and 9.6 ± 4.96), respectively (p < .001). There were statistically significant differences concerning 1- and 5-min Apgar scores with lower values in the MSAF group (p < .001 and .001, respectively). CONCLUSION: Our results support previous studies which indicate the presence of meconium can be associated with chronic fetal hypoxia as demonstrated by elevated fetal NRBC levels.

Placental Structure in Preterm Birth Among HIV-Positive Versus HIV-Negative Women in Kenya.

BACKGROUND: Preterm birth (PTB) is a major cause of infant morbidity and mortality in developing countries. Recent data suggest that in addition to Human Immunodeficiency Virus (HIV) infection, use of antiretroviral therapy (ART) increases the risk of PTB. As the mechanisms remain unexplored, we conducted this study to determine whether HIV and ART were associated with placental changes that could contribute to PTB. SETTING: We collected and evaluated placentas from 38 HIV-positive women on ART and 43 HIV-negative women who had preterm deliveries in Nairobi, Kenya. METHODS: Anatomical features of the placentas were examined at gross and microscopic levels. Cases were matched for gestational age and compared by the investigators who were blinded to maternal HIV serostatus. RESULTS: Among preterm placentas, HIV infection was significantly associated with thrombosis (P = 0.001), infarction (P = 0.032), anomalies in cord insertion (P = 0.02), gross evidence of membrane infection (P = 0.043), and reduced placental thickness (P = 0.010). Overall, preterm placentas in both groups were associated with immature villi, syncytial knotting, villitis, and deciduitis. Features of HIV-positive versus HIV-negative placentas included significant fibrinoid deposition with villus degeneration, syncytiotrophoblast delamination, red blood cell adhesion, hypervascularity, and reduction in both surface area and perimeter of the terminal villi. CONCLUSIONS: These results imply that HIV infection and/or ART are associated with morphological changes in preterm placentas that contribute to delivery before 37 weeks. Hypervascularity suggests that the observed pathologies may be attributable, in part, to hypoxia. Further research to explore potential mechanisms will help elucidate the pathways that are involved perhaps pointing to interventions for decreasing the risk of prematurity among HIV-positive women.

Multiple part umbilical cord entanglement and neonatal outcomes.

OBJECTIVE: Umbilical cord entanglement is known to be a major cause of fetal hypoxia and to be correlated with several neonatal complications, but almost all of the previous reports were restricted to nuchal cord. In this study, we retrospectively examined the correlation between multiple part cord entanglement and pregnancy outcomes. MATERIALS AND METHODS: A total of 2156 cases were recruited from term deliveries in our hospital from 2008 to 2012. We counted umbilical cord loop numbers not only for nuchal cord but also for trunk and limb cord entanglement. We classified the cases into three groups: no loop, single loop and multiple loops group. We statistically analyzed pregnancy outcomes statistically in the three groups. RESULTS: One thousand, four hundred and fifty-eight cases had no cord entanglement, 594 cases had single loop entanglement and 104 cases had multiple loops entanglement. Values of umbilical artery blood, pH (p = 0.002) and base excess (p < 0.001) showed significantly unfavorable status in entanglement cases, especially in the multiple loops group. A significantly larger percentage of neonates in the multiple loops group needed for oxygen (p < 0.001). CONCLUSION: Multiple umbilical cord entanglement is highly correlated with early neonatal unfavorable status and need for resuscitation.