Amniotic fluid abnormalities

Isolated polyhydramnios: Is a genetic evaluation of value?

OBJECTIVE

To analyze the risk for genetic aberrations and pregnancy outcomes in pregnancies with isolated polyhydramnios.

STUDY DESIGN

This was a retrospective study of singleton pregnancies complicated by isolated polyhydramnios that underwent genetic amniocentesis between 2016 and 2021. Clinical and laboratory data were collected and reviewed for these cases, including maternal demographics, prenatal sonographic findings, chromosomal microarray results, and pregnancy outcomes.

RESULTS

A total of 94 singleton pregnancies were included. Three (3.2%) cases with chromosomal abnormalities were detected, including 2 case of trisomy 21 and 1 of 22q21.1 microdeletion. One case was diagnosed as Prader-Willi syndrome caused by maternal uniparental disomy of chromosome 15. Perinatal death occurred in 1 case with severe polyhydramnios, and was retrospectively diagnosed as Bartter syndrome. Of the 90 infants survived, two were identified to have single gene disorders after birth by whole exome sequencing.

CONCLUSION

We first attempted to determine the value of exome sequencing in pregnancies with isolated polyhydramnios. Our results warrant more studies to evaluate advanced genetic testing technologies used in such pregnancies.

Metabolomic Profiling of Second-Trimester Amniotic Fluid for Predicting Preterm Delivery: Insights from NMR Analysis

Preterm delivery (PTD) is a notable pregnancy complication, affecting one out of every ten births. This study set out to investigate whether analyzing the metabolic composition of amniotic fluid (AF) collected from pregnant women during the second trimester of pregnancy could offer valuable insights into prematurity. The research employed 1H-NMR metabolomics to examine AF samples obtained from 17 women who gave birth prematurely (between 29+0 and 36+5 weeks of gestation) and 43 women who delivered at full term. The application of multivariate analysis revealed metabolites (dimethylglycine, glucose, myo-inositol, and succinate) that can serve as possible biomarkers for the prognosis and early diagnosis of preterm delivery. Additionally, pathway analysis unveiled the most critical metabolic pathways relevant to our research hypothesis. In summary, these findings suggest that the metabolic composition of AF in the second trimester can be a potential indicator for identifying biomarkers associated with the risk of PTD.

AFNet Algorithm for Automatic Amniotic Fluid Segmentation from Fetal MRI

Amniotic Fluid Volume (AFV) is a crucial fetal biomarker when diagnosing specific fetal abnormalities. This study proposes a novel Convolutional Neural Network (CNN) model, AFNet, for segmenting amniotic fluid (AF) to facilitate clinical AFV evaluation. AFNet was trained and tested on a manually segmented and radiologist-validated AF dataset. AFNet outperforms ResUNet++ by using efficient feature mapping in the attention block and transposing convolutions in the decoder. Our experimental results show that AFNet achieved a mean Intersection over Union (mIoU) of 93.38% on our dataset, thereby outperforming other state-of-the-art models. While AFNet achieves performance scores similar to those of the UNet++ model, it does so while utilizing merely less than half the number of parameters. By creating a detailed AF dataset with an improved CNN architecture, we enable the quantification of AFV in clinical practice, which can aid in diagnosing AF disorders during gestation.

Amniotic Fluid Disorders: From Prenatal Management to Neonatal Outcomes

Amniotic fluid volume assessment has become standard in the surveillance of fetal well-being, especially in high-risk pregnancies. Amniotic fluid disorders are a frequent and important topic in fetal and perinatal medicine. However, although important advances have been achieved, many important and challenging questions remain unanswered to date. An abnormally low amniotic fluid volume, referred to as oligohydramnios, has been traditionally considered a possible indicator of placental insufficiency or fetal compromise and is associated with an increased rate of obstetric interventions. An excess of amniotic fluid, referred to as polyhydramnios, may be secondary to fetal or maternal conditions and has been associated with a variety of adverse pregnancy outcomes, especially when it is severe. The ultrasonographic detection of an amniotic fluid disorder should prompt a proper workup to identify the underlying etiology. Data on the association of isolated oligohydramnios or idiopathic polyhydramnios with adverse obstetric and perinatal outcomes are conflicting. While the management of secondary oligohydramnios is usually guided by the underlying condition, the management of isolated oligohydramnios is poorly defined. Similarly, the management of idiopathic and secondary polyhydramnios is not yet standardized. There is an urgent need for randomized clinical trials to provide stronger recommendations on the management of these two common conditions.

Heavy metal ion concentration in the amniotic fluid of preterm and term pregnancies from two cities with different industrial output

The growth and development of the fetus is a complex phenomenon that can be influenced by several variables. High quantities of heavy metal ions in the amniotic fluid have been linked to poor health, especially in industrial, polluted and poor areas. The aim of the present study was to assess the differences in the concentration of these ions between preterm (weeks 15-37) and term pregnancies (starting at week 37). Another objective was to compare pregnancies from two cities with different industry levels. Two sample lots from two Romanian cities were analyzed. A total of 100 patients from Timisoara were compared with 60 from Petrosani, a heavy industry city in Romania. Demographic data were collected, and amniocentesis was performed on all women. Lead (Pb), copper (Cu), nickel (Ni), cadmium (Cd), arsenic (As), iron (Fe) and zinc (Zn) concentrations were assessed. Descriptive and analytical statistics were performed using the Mann-Whitney U test for non-parametric data and the Fisher's exact test for categorical data. In addition, categorical data was represented graphically. In the Timisoara cohort, the differences in heavy metal concentrations between preterm and term pregnancies were not statistically significant. In the Petrosani cohort, however, the concentrations of Zn (P=0.02606) and Cd (P=0.01512) were higher in preterm than in term pregnancies. When comparing the two cohorts as a whole, the concentration of Pb (P=0.04513), Cd (P=0.00002), As (P=0.03027) and Zn (P<0.00001) were higher in the patients from Petrosani than in those from Timisoara. Only Cu concentrations were higher in the Timisoara cohort (P<0.00001). The concentrations of Ni (P=0.78150) and Fe (P=0.44540) did not differ statistically. Thus, amniocentesis is an important diagnostic and exploratory tool in determining differences in the concentrations of elements such as heavy metal ions. Research over a longer period of time should be carried out to examine the relation between heavy metal ions concentration and possible postnatal health outcomes.

Contribution of aquaporins in the transamniotic water flux

We explored the contribution of each aquaporin (AQP) expressed in human amnion in the transcellular water flux across the human amnion. Human amnion was placed between two lucite chambers and net water transport (Jw) was recorded by applying a hydrostatic (7 cm H₂O) and an osmotic (40 mOsm PEG 8000) pressure gradients. The hydrostatic (Phydr) and osmotic (POsm) permeabilities were calculated before and after the blocking of AQPs. Phdr showed no significant difference after the blocking of AQPs, while POsm was dramatically reduced. Interestingly, we also found that the blocking of AQP1 produced the highest decrease of POsm (80 ± 1%). Our results strongly suggested that AQP1 seems to contribute more to the maintenance of AF volume homeostasis.

Correlation of amniotic fluid index and placental aquaporin 1 levels in terms of preeclampsia

INTRODUCTION

Aquaporin 1 (AQP1) plays an important role in regulation of maternal-fetal fluid exchange and amniotic fluid volume. This present study aimed to determine the relationship between amniotic fluid index and placental AQP1 levels in terms of preeclampsia, and to reveal possible pathophysiological changes of AQP1 expression under preeclamptic conditions.

METHODS

Placental tissues and medical records information were obtained from 389 preeclamptic and 447 uncomplicated pregnancies. Placental AQP1 levels were analyzed by molecular biological methods, DNA methylation within gene promotor was determined by targeted bisulfite sequencing assay.

RESULTS

Here, we found that preeclamptic pregnancy had a greater frequency of oligohydramnios, and higher placental AQP1 levels. There was a significantly inverse correlation between amniotic fluid index and placental AQP1 levels in preeclampsia cases. Additionally, the increased AQP1 was correlated with a decreased DNA methylation within its gene promoter.

DISCUSSION

Overall, this was the first description that a greater frequency of oligohydramnios in preeclampsia was strongly associated with reprogrammed AQP1 expression via a DNA methylation-mediated epigenetic mechanism. This study suggested AQP1 might play an important role in regulating maternal-fetal fluid balance under preeclamptic conditions, providing new information for further understanding the pathophysiological mechanism of oligohydramnios in preeclampsia.

Amniotic fluid index measurements in the second and third trimester and correlation to fetal biometric parameters - new reference based on a big retrospective data

INTRODUCTION

Estimation of amniotic fluid volume (AFV) is part of routine obstetric sonography which reflects maternal-fetal circulation efficiency, fetal hemodynamic status, and a parameter for predicting adverse neonatal outcome. Fetal weight is positively correlated with AFV. Therefore, our objective is to provide a new nomogram of AFV indices and to evaluate the relation between AFV and fetal biometric parameters.

MATERIALS AND METHODS

Retrospective cohort study between 2011 and 2018, at a large tertiary medical center. Data were collected from medical charts of prenatal sonographic evaluation of normal pregnancies, including routine estimation of AFV by using amniotic fluid index (AFI). Generalized estimating equations model was used to study the association between AFI, gestational age and fetal biometric parameters. Centiles were calculated using the Generalized Additive Models for Location, Scale, and Shape model. Box-Cox-t distribution and smoothing splines were used.

RESULTS

Analysis included 28,650 pregnancies. From 25 to 41 weeks gestation, the median and fifth percentile AFI gradually decreased from 174 (IQR 157-193) to 138 mm (IQR 107-173) and from 125 to 68 mm, respectively. The change in the 95th percentile was less significant, ranging around 230 mm throughout pregnancy. Multivariate regression analysis demonstrated a significant correlation between AFI and maternal body mass index (B = -0.147; CI = -0.27 to -0.02), gestational age (B = -11.8; CI = -12.5 to -11.4), estimated fetal weight (EFW) (B = 0.05; CI = 0.049-0.053) and abdominal circumference (AC) (B = 0.94; CI = 0.95-1). There was no correlation between AFI and other fetal biometric parameters.

CONCLUSIONS

We suggest new AFI indices of singleton pregnancies. We found a positive correlation between AFI and EFW and AC.

Successful outcome of giant chorioangioma

Chorioangioma is the most common benign non trophoblastic tumor of the placenta. It is a rare presentation with incidence of 0.6-1% of all pregnancies. It is associated with feto maternal complications like polyhydramnios, cervical incompetence, preterm labor, increased rate of cesarean delivery, abruptio placentae, malpresentation, postpartum hemorrhage, fetal growth restriction, fetal anemia, fetal thrombocytopenia, non immune hydrops, fetal cardiac failure, cerebral embolism, cerebral infarction, intrauterine fetal and neonatal death. Ultrasound is the gold standard for diagnosis . Here we present a case of giant chorioangioma of 6 * 5 cm with complication of polyhydramnios, preterm labor, abruptio placenta and placenta previa successfully managed with good maternal and fetal outcome.

Daidzein supplementation enhances embryo survival by improving hormones, antioxidant capacity, and metabolic profiles of amniotic fluid in sows

Daidzein (DAI) is a kind of natural isoflavonic phytoestrogen with estrogenic activity. However, little is known about its influence on early fetal growth in mammalian animals. The current study aimed to explore the characteristics of amniotic fluid exposure to dietary DAI using ¹H NMR-based metabolomics and biochemical analysis. Here, we found that DAI supplementation at a dose of 200 mg kg^-1 significantly enhanced the number of viable embryos at the early gestation stage (P < 0.05). DAI significantly elevated the concentrations of estrogen (E) and insulin-like growth factor-I (IGF-I) in the amniotic fluid (P < 0.05). Moreover, DAI tended to increase the concentration of progesterone, but decrease the concentration of tumor necrosis factor α (TNF-α) in the amniotic fluid (0.05 < P < 0.10). Interestingly, the activity of glutathione peroxidase (GSH-Px) was higher in the DAI group than in the CON group (P < 0.05). An ¹H NMR-based metabolomics analysis identified and quantified more than 30 compounds in the amniotic fluid, and some critical metabolites such as arginine, creatine, and citrate were found to be significantly elevated upon DAI supplementation (P < 0.05). Importantly, the metabolic pathways involved in arginine and proline metabolisms were found to be significantly affected by DAI. Collectively, dietary DAI may improve embryo survival by improving hormones, antioxidant capacity, and metabolic profiles in the maternal amniotic fluid.

Prenatal exposure to isolated amniotic fluid disorders and the risk for long-term cardiovascular morbidity in the offspring

Amniotic fluid (AF) abnormalities are often associated with short-term adverse pregnancy outcomes, including cardiovascular-related. We sought to assess whether in utero exposure to AF abnormalities increases the risk for long-term cardiovascular morbidity of the offspring. We examined the incidence of cardiovascular disorders in singletons exposed and non-exposed to isolated oligohydramnios or polyhydramnios. Cardiovascular morbidity was assessed up to the age of 18 years according to a predefined set of ICD-9 codes. A Kaplan-Meier survival curves were used to compare cumulative morbidity incidence. A Cox proportional hazards model was constructed to control for confounders. During the study period, 195,943 newborns met the inclusion criteria, of which 2.0% (n = 4063) were in pregnancies diagnosed with isolated oligohydramnios and 2.9% (n = 5684) in pregnancies with isolated polyhydramnios. Children exposed to isolated AF disorders had significantly higher rates of long-term cardiovascular morbidity (p=.042). Children exposed to isolated oligohydramnios had higher cumulative incidence of cardiovascular morbidity (log-rank test p=.026) compared to unexposed children, opposing to what was demonstrate when comparing polyhydramnios vs. normal AFV (log-rank test p=.749). In the Cox regression model, while controlling for confounders, isolated oligohydramnios were found to be independently associated with long-term cardiovascular morbidity of the offspring.

Aquaporin 1 affects pregnancy outcome and regulates aquaporin 8 and 9 expressions in the placenta

To explore the effects of aquaporin (AQP) 1 on pregnancy outcome and the association between expression of AQP1 and other AQPs in the placenta and foetal membranes, the rate of copulatory plugs and pregnancy, amniotic fluid (AF) volume, osmolality and composition were determined in AQP1-knockout (AQP1^−/−) mice at different gestational days (GD). The expression and location of AQP1 and other AQPs in the placenta and foetal membranes of AQP1^−/− mice, AQP1-siRNA transfected WISH cells and oligohydramnios patients were also detected. Compared to control mice, AQP1^−/− mice exhibited reduced copulation plug and successful pregnancy rates, but these effects were accompanied by a larger AF volume and lower AF osmolality at late gestation. AQP9 expression was significantly decreased in the placenta and foetal membranes of AQP1^−/− mice, while AQP8 level was elevated in the foetal membranes of AQP1^−/− mice. Moreover, AQP9 expression was suppressed in WISH cells after AQP1 downregulation. Furthermore, AQP9 expression was associated with AQP1 level in the placenta and foetal membranes in oligohydramnios. AQP1 may play a critical role in regulating pregnancy outcome and maternal-foetal fluid homeostasis. Changes in AQP1 expression may lead to compensatory alterations in AQP8 and AQP9 expression in the placenta.

Aquaporins during pregnancy

Aquaporins (AQPs) are water channels proteins that facilitate water flux across cell membranes in response to osmotic gradients. Despite of the differences in the mammalian placentas, the conserved combination of AQPs expressed in placental and fetal membranes throughout gestation suggests that these proteins may be important in the regulation of fetal water homeostasis. Thus, AQPs may regulate the amniotic fluid volume and participate in the trans-placental transfer of water. Apart from their classical roles, recent studies have revealed that placental AQPs may also cooperate in cellular processes such as the migration and the apoptosis of the trophoblasts. Aquaglyceroporins can also participate in the energy metabolism and in the urea elimination across the placenta. Many factors including oxygen, hormones, acid-basis homeostasis, maternal dietary status, interaction with other transport proteins and osmotic stress are proposed to regulate their expression and function during gestation and alterations result in pathological pregnancies.

The association between isolated oligohydramnios at term and placental pathology in correlation with pregnancy outcomes

INTRODUCTION

Isolated term oligohydramnios (ITO) is an obstetrical complication of which the etiology, management, and clinical importance are controversial. In attempt to deepen our understanding, we aimed to study placental pathology and pregnancy outcomes in pregnancies complicated by ITO.

MATERIALS AND METHODS

- Maternal demographics, neonatal outcomes, and placental histopathology reports of all pregnancies complicated by ITO at 37^0/7 to 41^0/7 weeks were reviewed. Excluded were cases complicated by hypertensive disorders, intrauterine fetal growth restriction, placental abruption, and deliveries of undiagnosed small for gestational age neonates. Results were compared between the ITO group and a control group matched for gestational age and mode of delivery. Placental lesions were classified according to the current "Amsterdam" criteria. Composite adverse neonatal outcome was defined as one or more of the following early complications: neonatal intensive care unit admission, sepsis, blood transfusion, phototherapy, respiratory morbidity, cerebral morbidity, necrotizing enterocolitis, or death.

RESULTS

The study group included 108 patients with ITO that were compared to matched controls. Placentas from the ITO group were characterized by higher rates of placental weights <10th centile (p < 0.001), abnormal cord insertion (p < 0.001), and maternal vascular malperfusion (MVM) lesions (p < 0.001). Neonates from the ITO group had lower birth weights (p < 0.002), and worse composite adverse neonatal outcome (p = 0.028) compared to controls.

CONCLUSION

- The current study demonstrates higher rates of placental MVM lesions, and worse neonatal outcome in pregnancies complicated by ITO. These novel findings suggest that ITO should be seen as part of the "placental insufficiency" spectrum.

Isolated oligohydramnios and long-term neurological morbidity of the offspring

This study aimed to assess the association between maternal-isolated oligohydramnios (IO) and offspring long-term neurological complications. A population-based retrospective cohort study was conducted, including all births at a single tertiary medical center in Israel between the years 1991 and 2014. Multiple pregnancies and potential pregnancy complications associated with oligohydramnios were excluded. The computerized obstetrical database was linked with the computerized dataset of all pediatric hospitalizations of the same medical center. Evaluation of cumulative neurological-associated hospitalizations rate over time was compared using a Kaplan-Meier survival curve. The Weibull survival parametric model was conducted to assess the neurological-associated hospitalization risk in the presence of IO, while accounting for potential confounders. A total of 190,259 pregnancies were included in the study, of which 4063 (2.13%) pregnancies were complicated with IO. Total neurological-related hospitalizations were significantly more common in the IO group (3.7% in the IO group and 3.0% in the comparison group, p = 0.005). Pervasive developmental disorder, movement disorders, developmental disorders, and degenerative and demyelization disorders were all specific neurological diagnoses significantly more common in the exposed group. The survival curve demonstrated a significantly higher cumulative hospitalization rate in the exposed group (log-rank p = 0.001). Using a multivariate model adjusting for gestational age, maternal age, and labor induction, an independent association between IO and long-term neurological morbidity of the offspring was observed (adjusted hazard ratio 1.203; 95% CI 1.02-1.42). In summary, a significant association was found between pregnancies complicated by IO and long-term neurological morbidity of the offspring.

Anhydramnios in the Setting of Renal Malformations: The National Institutes of Health Workshop Summary

Anhydramnios in the setting of severe malformations of the fetal kidney and urinary tract is associated with a high incidence of stillbirths and life-threatening complications, including severe pulmonary hypoplasia, umbilical cord compression, and perinatal asphyxia. To prevent such adverse outcomes, some centers in the United States and elsewhere are offering amniotic fluid restoration for women diagnosed with anhydramnios in the setting of fetal renal malformations. The procedures include infusions of amniotic fluid substitutes (normal saline), percutaneously or through an amnioport-an implanted system for serial or continuous infusion of normal saline to maintain the desired amniotic fluid volume. The procedures are intended to prevent pulmonary hypoplasia and allow the pregnancy to progress closer to term gestation, enabling postnatal renal management, including long-term dialysis and renal transplantation. However, these procedures have not been recommended as standard of care by the professional societies because there are many knowledge gaps, including few data on short-term and long-term renal outcomes. The available diagnostic methods do not provide reliable prognostic information, and the current maternal and fetal interventions have not been standardized. To address these unresolved issues and to propose a research agenda, the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Institute of Diabetes and Digestive and Kidney Diseases invited a panel of experts to a workshop in August 2016. This report provides a summary of that meeting.

A clinical scoring system to predict the need for extensive resuscitation at birth in very low birth weight infants

Background

To analyze the risk factors for extensive cardiopulmonary resuscitation in the delivery room and develop a prediction model for outcomes in very low birth weight (VLBW) infants.

Methods

The sample was 5298 VLBW infants registered in the Korean neonatal network database from 2013 to 2015. Univariate and multivariate analyses were used to analyze the risk factors for extensive resuscitation. In addition, a multivariable model predicting extensive resuscitation in VLBW infants was developed.

Results

Univariate regression analysis of antenatal factors showed that lower gestational age, lower birth weight, birth weight less than third percentile, male sex, maternal hypertension, abnormal amniotic fluid volume, no antenatal steroid use, outborn, and chorioamnionitis were associated with extensive resuscitation at birth. Lower gestational age (25 to 27 gestational weeks, odds ratio [OR] and 95% confidence interval [CI]: 3.003 [1.977–4.562]; less than 25 gestational weeks, OR and 95% CI: 4.921 [2.926–8.276]), birth weight less than 1000 g (OR and 95% CI: 1.509 [1.013–2.246]), male sex (OR and 95% CI: 1.329 [1.002–1.761]), oligohydramnios (OR and 95% CI: 1.820 [1.286–2.575]), polyhydramnios (OR and 95% CI: 6.203 [3.185–12.081]), and no antenatal steroid use (OR and 95% CI: 2.164 [1.549–3.023]) were associated on multivariate regression analysis. The final prediction model for extensive resuscitation included gestational age, amniotic fluid, and antenatal steroid use. It presented a sensitivity of 0.795 and specificity of 0.575 in predicting extensive resuscitation at birth, corresponding to a score cut-off of 2. The area under the receiver operating characteristic curve was 0.738.

Conclusions

Lower gestational age, abnormal amniotic fluid volume, and no use of antenatal steroid in VLBW infants are important predictors of extensive resuscitation in the delivery room.

Fetal Evaluation and Airway Management

Congenital causes of airway obstruction once noted at birth are now diagnosed prenatally. The adoption of ex utero intrapartum treatment has allowed for planned airway stabilization on placental support, dramatically decreasing the incidence of hypoxic injury or peripartum demise related to neonatal airway obstruction. Airway access is gained either through laryngoscopy, bronchoscopy, or a surgical airway. In complete airway obstruction, primary resection of the obstructing lesion may be performed before completion of delivery. This article reviews the current and emerging methods of fetal evaluation, indications for ex utero intrapartum treatment, and provides a detailed description of the procedure and necessary personnel.

Oxidative stress biomarkers in amniotic fluid of pregnant women with hypothyroidism

Purpose: Hypothyroidism in pregnancy is the serious state that may lead to fetal morbidity and mortality. Oxidative stress biomarkers in the amniotic fluid can provide important information on the health, development and maturation of the fetus during pregnancy. In this study, we examined whether maternal hypothyroidism contributes to increased oxidative stress biomarkers in the amniotic fluid during the first trimester of pregnancy. Materials and methods: The study was conducted on healthy pregnant women and pregnant women with hypothyroidism (gestational age: 16-18 weeks). Oxidative stress biomarkers, such as superoxide anion (O₂^•-), hydrogen peroxide (H₂O₂), nitric oxide (NO), peroxynitrite (ONOO^-), lipid peroxide (LPO), reduced glutathione (GSH) and oxidized glutathione (GSSG) were assayed in the amniotic fluid. Results: The results of this study indicated that concentrations of O₂^•- and NO are significantly higher, while the concentration of H₂O₂ is significantly lower in the amniotic fluid of pregnant women with hypothyroidism in comparison to healthy pregnant women. There were no differences in concentrations of LPO, GSH and GSSG among tested groups. Also, we found that amniotic fluid concentration of O₂^•- is negatively correlated with the body weight and Apgar score values of the newborns. Conclusion: These results suggest that pregnancy hypothyroidism is characterized by the amniotic fluid oxidative stress. Incorporation of the oxidative stress biomarkers measurement in the amniotic fluid may be of clinical importance in the management of pregnancy hypothyroidism.

Iodine Storage and Metabolism of Mild to Moderate Iodine-Deficient Pregnant Rats

BACKGROUND

Severe iodine deficiency during pregnancy results in neurodevelopmental disorders in children, while the consequences of mild to moderate iodine deficiency (MMID) are uncertain. The concentration of iodine in the thyroid is the most accurate indicator of iodine nutrition. This study aimed to evaluate whether the iodine stores in the thyroid cover the needs of the mother and the fetus in iodine-sufficient and MMID conditions by inductively coupled plasma-mass spectrometry.

METHODS

One hundred four-week-old female Wistar rats were randomly divided into MMID (low iodine intake [L]) and normal (normal iodine intake [N]) groups. The rats were fed for the next three months, and after pregnancy they were further divided into two subgroups, respectively: low iodine pregnancy (LP) and low iodine pregnancy with iodine supplement (LP+), and normal iodine intake pregnancy (NP) and normal iodine intake pregnancy with iodine supplement (NP+). The iodine intake of pregnant rats in the NP+ and LP+ groups was twice as much as in the NP and LP groups. The rats were sacrificed on gestational day 15 and postnatal day 7. The iodine concentration in the thyroid of the maternal and newborn rats, maternal serum, placenta, and amniotic fluid were determined by inductively coupled plasma-mass spectrometry.

RESULTS

The concentration of iodine in the thyroid of the N group was significantly higher than that in the L group before pregnancy. The concentration of iodine in the maternal thyroids of the LP group decreased during pregnancy, whereas that of the NP group did not change significantly. There was no significant difference in the iodine concentration in the thyroid of mothers and offspring between the NP and NP+ groups, but it was significant between LP and LP+ groups. The concentration of iodine in amniotic fluid was significantly different between the four groups.

CONCLUSION

There is sufficient iodine storage in the thyroid of maternal rats with normal iodine intake during pregnancy, and there is no need for iodine supplementation. However, iodine stores are insufficient in rats with MMID. Iodine supplementation can increase the iodine concentration in the thyroid of maternal rats with MMID and their offspring, as well as in the amniotic fluid during pregnancy.

Outcome of pregnancy in women diagnosed with idiopathic polyhydramnios

INTRODUCTION

Polyhydramnios is present in approximately 2% of pregnancies and it has been associated with a variety of adverse pregnancy outcomes.

OBJECTIVES

The aim of our study was to evaluate the association between polyhydramnios and adverse pregnancy outcomes.

METHODS

This was a retrospective case control study of 288 singleton pregnancies delivered in the Rotunda Hospital, Dublin, between 2013 and 2014. Polyhydramnios was defined as: (i) amniotic fluid index (AFI) ≥ 25 cm; (ii) maximal vertical pocket (MVP) of ≥8 cm; and (iii) a gestational age-specific threshold for AFI. Demographic information, obstetric and neonatal outcomes were obtained by review of hospital databases. Exclusion criteria included gestational or pre-existing diabetes, multiple pregnancy, carrying a fetus with structural or chromosomal abnormalities, Rhesus factor isoimmunisation, and TORCH screen positive. Outcomes were compared with outcomes of those without polyhydramnios.

RESULTS

A total of 8798 deliveries occurred during the study period. The frequency of polyhydramnios was 1.6%. One hundred and forty-four women were selected in each group. There was no significant difference in preterm deliveries, low birth weight, low Apgar score at one minute and five minutes and perinatal mortality. However, increase in caesarean delivery rate (43.1% vs 21.5%), number of fetal distresses (17.4% vs 6.9%) and number of neonatal intensive care unit (NICU) admissions (17.4% vs 4.9%) were observed in our study.

CONCLUSION

In conclusion, idiopathic polyhydramnios is associated with specific adverse outcomes, such as higher rate of caesarean delivery, fetal distress and NICU admissions. Therefore, close surveillance of these pregnancies is required, especially near term.

Polyhydramnios and cerebellar atrophy: a prenatal presentation of mitochondrial encephalomyopathy caused by mutations in the FBXL4 gene

Severe recessive mitochondrial myopathy caused by FBXL4 gene mutations may present prenatally with polyhydramnios and cerebellar hypoplasia. Characteristic dysmorphic features are: high and arched eyebrows, triangular face, a slight upslant of palpebral fissures, and a prominent pointed chin. Metabolic investigations invariably show increased serum lactate and pyruvate levels.

Role of the Placental Vitamin D Receptor in Modulating Feto-Placental Growth in Fetal Growth Restriction and Preeclampsia-Affected Pregnancies

Fetal growth restriction (FGR) is a common pregnancy complication that affects up to 5% of pregnancies worldwide. Recent studies demonstrate that Vitamin D deficiency is implicated in reduced fetal growth, which may be rescued by supplementation of Vitamin D. Despite this, the pathway(s) by which Vitamin D modulate fetal growth remains to be investigated. Our own studies demonstrate that the Vitamin D receptor (VDR) is significantly decreased in placentae from human pregnancies complicated by FGR and contributes to abnormal placental trophoblast apoptosis and differentiation and regulation of cell-cycle genes in vitro. Thus, Vitamin D signaling is important for normal placental function and fetal growth. This review discusses the association of Vitamin D with fetal growth, the function of Vitamin D and its receptor in pregnancy, as well as the functional significance of a placental source of Vitamin D in FGR. Additionally, we propose that for Vitamin D to be clinically effective to prevent and manage FGR, the molecular mechanisms of Vitamin D and its receptor in modulating fetal growth requires further investigation.

Polyhydramnios in Lrp4 knockout mice with bilateral kidney agenesis: Defects in the pathways of amniotic fluid clearance

Amniotic fluid volume during mid-to-late gestation depends mainly on the urine excretion from the foetal kidneys and partly on the fluid secretion from the foetal lungs during foetal breathing-like movements. Urine is necessary for foetal breathing-like movements, which is critical for foetal lung development. Bilateral renal agenesis and/or obstruction of the urinary tract lead to oligohydramnios, which causes infant death within a short period after birth due to pulmonary hypoplasia. Lrp4, which functions as an agrin receptor, is essential for the formation of neuromuscular junctions. Herein, we report novel phenotypes of Lrp4 knockout (Lrp4(-/-)) mice. Most Lrp4(-/-) foetuses showed unilateral or bilateral kidney agenesis, and Lrp4 knockout resulted in polyhydramnios. The loss of Lrp4 compromised foetal swallowing and breathing-like movements and downregulated the expression of aquaporin-9 in the foetal membrane and aquaporin-1 in the placenta, which possibly affected the amniotic fluid clearance. These results suggest that amniotic fluid removal was compromised in Lrp4(-/-) foetuses, resulting in polyhydramnios despite the impairment of urine production. Our findings indicate that amniotic fluid removal plays an essential role in regulating the amniotic fluid volume.

Aquaporins and Fetal Membranes From Diabetic Parturient Women: Expression Abnormalities and Regulation by Insulin

CONTEXT

During pregnancy, aquaporins (AQPs) expressed in fetal membranes are essential for controlling the homeostasis of the amniotic volume, but their regulation by insulin was never explored in diabetic women.

OBJECTIVE

The aim of our study was to investigate the involvement of AQPs 1, 3, 8, and 9 expressed in fetal membranes in diabetic parturient women and the control of their expression by insulin.

DESIGN AND PARTICIPANTS

From 129 fetal membranes in four populations (controls, type 1, type 2 [T2D], and gestational diabetes [GD]), we established an expression AQP profile. In a second step, the amnion was used to study the control of the expression and functions of AQPs 3 and 9 by insulin.

MAIN OUTCOMES AND MEASURES

The expression of transcripts and proteins of AQPs was studied by quantitative RT-PCR and ELISA. We analyzed the regulation by insulin of the expression of AQPs 3 and 9 in the amnion. A tritiated glycerol test enabled us to measure the impact of insulin on the functional characteristics. Using an inhibitor of phosphatidylinositol 3-kinase, we analyzed the insulin intracellular signaling pathway.

RESULTS

The expression of AQP3 protein was significantly weaker in groups T2D and GD. In nondiabetic fetal membranes, we showed for the amnion (but not for the chorion) a significant repression by insulin of the transcriptional expression of AQPs 3 and 9, which was blocked by a phosphatidylinositol 3-kinase inhibitor.

CONCLUSION

In fetal membranes, the repression of AQP3 protein expression and functions observed in vivo is allowed by the hyperinsulinism described in pregnant women with T2D or GD.

Prenatal consultation for foetal anomalies requiring surgery

BACKGROUND

During prenatal screening of pregnant women, foetal anomalies requiring surgery may be diagnosed. Healthcare providers should have a basic knowledge of these diseases, including their workup, comorbidities, prognosis, treatment options and any considerations that need to be made in planning for birth.

AIM

This article aims to provide this information by summarising the most recent literature for some of the most commonly diagnosed foetal anomalies requiring surgical correction.

METHODS

English language studies on prenatal diagnostic modalities, abdominal wall defects, congenital diaphragmatic hernias, surgical conditions leading to airway compromise, hydrops fetalis, intestinal obstruction and abdominal cysts were retrieved from the PubMed database.

FINDINGS

The most recent and relevant literature is summarised regarding the above listed paediatric conditions. The incidence and prevalence (when available), prognosis, workup, common comorbidities, foetal interventions and special birth considerations (when applicable), and postnatal surgical treatment options are reviewed.

CONCLUSIONS

Healthcare providers will occasionally encounter foetal anomalies which may require surgery while performing prenatal screening. They may need to provide early counselling to expectant parents to inform their expectations. When indicated, referrals should be made to a foetal care centre for prenatal consultation. For conditions which may cause danger or distress to the foetus in the immediate postnatal period, preparations should be made to ensure sufficient resources are available at the location of birth.

Severe midtrimester oligohydramnios: treatment strategies

PURPOSE OF REVIEW

Nearly 1% of pregnancies are affected by some type of midtrimester oligohydramnios. Evidence is currently accumulating that suggests the better efficacy of the new therapeutic procedures relative to conventional management. This review summarizes the available evidence.

RECENT FINDINGS

The prolongation of the period between the diagnosis of oligohydramnios and delivery following amnioinfusion and amniopatch techniques appears to be strongly associated with the gestational age and whether the situation was based on rupture of the membranes or not. Case series reveal that amnioinfusion significantly improves the perinatal outcome and prolongs the pregnancy in severe second-trimester oligohydramnios in both idiopathic cases and those involving rupture of the amniotic membranes [preterm prelabor rupture of the membranes (PPROM)]. There is clear evidence of a lower frequency of perinatal complications and successfully prolonged gestation in iatrogenic PPROM after the amniopatch technique relative to population controls.

SUMMARY

Identification of potentially modifiable risk factors for the successful prolongation of pregnancy complicated with midtrimester oligohydramnios, and previable PPROM is needed for the improvement of treatment strategies and prognosis. Randomized trials are needed to determine whether amniotic fluid-replenishing strategies can improve pregnancy outcomes.

Placental tumor (chorioangioma) as a cause of polyhydramnios: a case report

Placental chorioangioma is the most common type of placental tumor. It is usually symptomless and may be associated with serious maternal and fetal complication when it reaches a large size. We presented a case of an angiomatous type of placental hemangioma diagnosed in the second trimester of pregnancy in a patient with polyhydramnios. A normal volume of amniotic fluid was successfully achieved by three amnioreductions with conservative management. The size of the placental tumor remained the same from the time of diagnosis to the end of pregnancy. A term labor was uncomplicated and a healthy newborn was delivered. Macroscopic and microscopic examination of the placenta confirmed the diagnosis. Despite the rarity of placental tumors, they should be considered as differential diagnosis in cases of polyhydramnios.

Exploring the origins of asthma: Lessons from twin studies

This thesis explores the contribution of twin studies, particularly those studies originating from the Danish Twin Registry, to the understanding of the aetiology of asthma. First, it is explored how twin studies have established the contribution of genetic and environmental factors to the variation in the susceptibility to asthma, and to the variation in several aspects of the clinical expression of the disease such as its age at onset, its symptomatology, its intermediate phenotypes, and its relationship with other atopic diseases. Next, it is explored how twin studies have corroborated theories explaining asthma's recent increase in prevalence, and last, how these fit with the explanations of the epidemiological trends in other common chronic diseases of modernity.

Polyhydramnios: Causes, Diagnosis and Therapy

Polyhydramnios is defined as a pathological increase of amniotic fluid volume in pregnancy and is associated with increased perinatal morbidity and mortality. Common causes of polyhydramnios include gestational diabetes, fetal anomalies with disturbed fetal swallowing of amniotic fluid, fetal infections and other, rarer causes. The diagnosis is obtained by ultrasound. The prognosis of polyhydramnios depends on its cause and severity. Typical symptoms of polyhydramnios include maternal dyspnea, preterm labor, premature rupture of membranes (PPROM), abnormal fetal presentation, cord prolapse and postpartum hemorrhage. Due to its common etiology with gestational diabetes, polyhydramnios is often associated with fetal macrosomia. To prevent the above complications, there are two methods of prenatal treatment: amnioreduction and pharmacological treatment with non-steroidal anti-inflammatory drugs (NSAIDs). However, prenatal administration of NSAIDs to reduce amniotic fluid volumes has not been approved in Germany. In addition to conventional management, experimental therapies which would alter fetal diuresis are being considered.

Chinese herbal medicine in treatment of polyhydramnios:a meta-analysis and systematic review

OBJECTIVE

To compare the efficacy of Chinese herbal medicine (therapy A) or Chinese herbal medicine plus indomethacin (therapy B) with that of indomethacin alone (therapy C) in treating polyhydramnios.

METHODS

Literatures published up to April 2012 were retrieved from PubMed, Embase and Cochrane library, Chinese National Knowledge Infrastructure (CNKI), Chinese Scientific and Technological Periodical Database (VIP), Wangfang, and Traditional Chinese Medicine online. Two researchers collected data independently. The assessment of methodological quality was based on Cochrane handbook and the materials were analyzed with software RevMan 5.1.2. The outcome measure index was relative risk or difference of mean value (95% confidence interval). The following outcomes were evaluated (1) general clinical improvement rate; (2) maximum vertical pocket depth; (3) amniotic fluid index (AFI) value; (4) rate of fetal ductus arteriosus constriction; (5) incidence of adverse events.

RESULTS

Based on the search strategy, 5 trails involving 1017 patients were finally included. Compared with therapy C, therapy A decreased the rate of fetal ductus arteriosus constriction (P<0.01). Therapy B was more effective than therapy C in general clinical improvement and decrease of AFI for polyhydramnios (P<0.01). No serious adverse events were reported in therapy A and therapy B.

CONCLUSIONS

Compared with therapy C, therapy A and therapy B may appear to be more effective for polyhydramnios. However, the exact effect needs to be confirmed with well-designed large-scale clinical trials.

Breech repositioning unresponsive to Webster technique: coexistence of oligohydramnios

OBJECTIVE

The purpose of this report is to describe the results of a pregnant woman demonstrating breech fetal presentation who was managed with Webster technique in the presence of oligohydramnios.

CLINICAL FEATURES

A 23-year-old primigravida woman sought chiropractic care for the management of breech presentation and bilateral sacroiliac arthralgia at 34 weeks' gestation.

INTERVENTION AND OUTCOME

Sacral manipulation and abdominal effleurage (Webster Technique) was used to address breech presentation and sacroiliac arthralgia for a total of 7 treatments over a 3 1/2-week duration. The patient's sacroiliac pain reduced from 8/10 to 3/10. However, breech presentation was unchanged at each treatment. At a scheduled prenatal surveillance during the 37th week of gestation, the midwife detected vaginal bleeding and reduced fundal height, which resulted in hospitalization, diagnosis of oligohydramnios, and an emergency cesarean delivery.

CONCLUSION

For this particular patient, the breech presentation was not corrected using the Webster technique. Clinicians who use the Webster technique to manage breech fetal presentation should be aware of undiagnosed comorbidities as a complicating factor in clinical presentation. Screening for previously undiagnosed comorbidities, such as oligohydramnios, must be considered.

Pre-B cell colony enhancing factor (PBEF/NAMPT/Visfatin) and vascular endothelial growth factor (VEGF) cooperate to increase the permeability of the human placental amnion

Fluid efflux across the region of the amnion overlying the placenta is an essential component of the intramembranous absorption pathway that maintains amniotic fluid volume homeostasis. Dysregulation of this pathway may result in adverse pregnancy outcomes, however the factors controlling amnion permeability are unknown. Here, we report a novel mechanism that increases placental amnion permeability. Pre-B Cell Colony Enhancing Factor (PBEF) is a stress-responsive cytokine expressed by the human amnion, and is known to induce Vascular Endothelial Growth Factor (VEGF) production by other cell types. Interestingly, VEGF is up-regulated in the ovine amnion when intramembranous absorption is augmented. In this study, we show that PBEF induced VEGF secretion by primary human amniotic epithelial cells (AEC) derived from the placental amnion, as well as from the reflected amnion that lines the remainder of the gestational sac. Further, PBEF treatment led to the increased expression of VEGFR2 in placental AEC, but not reflected AEC. To test the hypothesis that PBEF and VEGF increase placental amnion permeability, we monitored the transfer of 2',7'-dichlorofluorescein (DCF) from the fetal to the maternal side of human amnion explants. A treatment regimen including both PBEF and VEGF increased the rate of DCF transfer across the placental amnion, but not the reflected amnion. In summary, our results suggest that by augmenting VEGFR2 expression in the placental amnion, PBEF primes the tissue for a VEGF-mediated increase in permeability. This mechanism may have important implications in amniotic fluid volume control throughout gestation.

Progesterone maintains amniotic tight junctions during midpregnancy in mice

The amniotic epithelium is in direct contact with the amniotic fluid and restricts fluid flux via the paracellular pathway by means of tight junctions (TJs). Several factors affect TJs to modulate the paracellular flux. Progesterone contributes to the antenatal formation and disappearance of TJs in uterine and mammary epithelial tissues. In this study, we investigated whether progesterone positively or negatively influences amniotic TJs. The administration of RU-486, a progesterone receptor (PR) antagonist, into pregnant mice adversely affects the localization and expression of claudin-3 and claudin-4 in the amniotic epithelium. RU-486 administration also increased the permeability of the amniotic membrane. In organ-cultured amniotic membranes, progesterone induced increases in claudin-3 and claudin-4 expression in a dose-dependent manner but did not influence their localization. PRs were also present in the amniotic epithelium during midpregnancy but they disappeared during late pregnancy. These results indicate that the progesterone/PR pathway maintains TJs in the amniotic epithelium during midpregnancy.

Biomarkers of oxidative stress in amniotic fluid and complications in pregnancy

OBJECTIVE

In this study, we tried to determine whether the activities of the primary antioxidant enzymes are detectable in amniotic fluid and whether they can be used as early biomarkers of complications in pregnancy such as pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), and bacterial vaginosis.

METHODS

This was a prospective study in which amniotic fluid was taken between 16 and 19 week of gestation. In all, 161 pregnant women were divided into two groups: study group - patients with the treated local infection, PIH, and GDM, and control group - healthy pregnant women. Levels of reduced glutathione (GSH) and activities of supeoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GSHR), glutathione S-transpherase (GST), xanthine oxidase (XOD) and lipid peroxidation (LP) were determined spectrophotometrically in amniotic fluid samples.

RESULTS

Concentration of malondialdehyde varied greatly between investigated groups. XOD and SOD activities, though very low, were present in amniotic fluid samples. Also, enzymes of glutathione cycle and GSH concentrations were detectable and showed certain variations.

CONCLUSION

Parameters of oxidative stress in amniotic fluid could be altered in certain pathological conditions. Their use as clinical biomarkers is limited due to great variations of amniotic fluid volume between patients which gives favor to hemolysate or serum of pregnant women.

Expression and distribution of tight junction proteins in human amnion during late pregnancy

Amnion is the innermost layer of the fetal membrane and has been suggested to regulate the volume of amniotic fluid via the amniotic epithelium. The transepithelial pathway is generally restricted by tight junctions (TJs). Thus far, human amniotic TJs have not been identified. In this study, we determined whether the human amniotic epithelium contains TJs. Reverse transcription polymerase chain reaction (RT-PCR) and western blotting analyses showed that the human amniotic epithelium has TJ components, such as occludin, ZO-1, and at least 2 types of claudins, i.e., claudin-4 and claudin-7. The TJ components were found to localize in the lateral membranes and cytoplasm at 35 weeks of gestation; these components disappeared from the lateral membrane at 37 weeks of gestation. Organ culturing of the amnion at 37 weeks gestation induced the relocalization of the TJ proteins from the cytoplasm to the lateral membranes. Furthermore, in cultured amniotic epithelial cells, dexamethasone induced the downregulation of the protein expression of TJs. These findings suggest that the human amniotic epithelium has TJs that disrupt during late pregnancy. The disruption may be induced by several factors such as glucocorticoids present in the amniotic fluid during late pregnancy.