The amniotic fluid index in normal human pregnancy

Amnioreduction vs expectant management in pregnancies with moderate to severe polyhydramnios

BACKGROUND

The rate of polyhydramnios is higher in pregnancies complicated by congenital anomalies. These pregnancies have higher rates of peripartum complications. Amnioreduction is offered to relieve maternal symptoms such as dyspnea, abdominal and respiratory discomfort, and other issues like satiety.

OBJECTIVE

This study aimed to report the rates of amnioreduction and its associated complications in pregnancies with moderate to severe polyhydramnios secondary to fetal anomalies. We also sought to determine if amnioreduction provided additional benefits, including prolongation of pregnancy and a decrease in the rates of peripartum morbidities associated with moderate to severe polyhydramnios.

STUDY DESIGN

This was a retrospective review of anomalous singleton pregnancies with moderate to severe polyhydramnios that were evaluated and delivered at a single center between 2013 and 2021. Peripartum outcomes were compared between pregnancies that underwent amnioreduction and those that were expectantly managed. Mann-Whitney U tests were used to compare continuous variables and Fisher's exact tests were used for categorical variables. A multiple regression model was created to understand the effects of amnioreduction on gestational age at delivery.

RESULTS

A total of 218 singleton pregnancies met the inclusion criteria of moderate to severe polyhydramnios in the study period. Of those, 110 patients (50.5%) underwent amnioreduction and 108 patients (49.5%) opted for expectant management. A total of 147 procedures were performed at a median gestational age of 32.5 weeks and a median of 1900 mL of amniotic fluid was removed per procedure. Complications occurred in 10.9% (n=16) of procedures, including preterm delivery within 48 hours in 5.4% cases (n=8). The median amniotic fluid index was higher in the amnioreduction group than in the expectant group (38.9 cm vs 35.5 cm; P<.0001). Patients who underwent amnioreduction had an earlier median gestational age at delivery (36.3 weeks vs 37.0 weeks; P=.048), however, the rates of spontaneous preterm delivery were similar. A higher percentage of women in the amnioreduction group had vaginal delivery (49.4% vs 30.5%; P=.01) and lower rates of uterine atony (2.4% vs 13.7%; P=.006). In the multiple linear regression analysis, the gestational age at delivery positively correlated with gestational age at amnioreduction after controlling for amniotic fluid volume (P<.0001; 95% confidence interval, 0.34-0.71). In addition, the patients in the amnioreduction group were twice as likely to have a vaginal delivery (P=.02).

CONCLUSION

Amnioreduction in the setting of moderate-severe polyhydramnios has a reasonably low rate of complications but does not provide any benefits in terms of prolonging the pregnancy. The procedure may increase the likelihood of vaginal delivery and lower the rates of uterine atony.

Incomplete distal renal tubular acidosis uncovered during pregnancy: A case report

BACKGROUND

Renal tubular acidosis (RTA) is a renal cause of non-anion-gap metabolic acidosis characterized by low urinary ammonia excretion. This condition has a low prevalence, and various congenital and acquired etiologies. To date, only a few cases of idiopathic RTA uncovered during pregnancy have been reported.

CASE SUMMARY

A previously healthy 32-year-old Korean woman at 30 wk of gestation was admitted to Pusan National University Hospital with preterm labor. At admission, the patient presented with hypokalemia, non-anion-gap metabolic acidosis, and nephrocalcinosis. Distal RTA was diagnosed based on laboratory blood and urine findings and imaging examinations. Various tests, including next-generation gene sequencing panels for nephropathy, were performed to determine the etiology of the disease, which indicated that it was idiopathic. The patient received sodium bicarbonate and potassium chloride supplementation. After 3 wk, she delivered a baby who was subsequently diagnosed with corpus callosum agenesis and colpocephaly. During regular follow-ups for 6 mo postpartum, her hypokalemia and metabolic acidosis were gradually resolved, and medications eventually discontinued.

CONCLUSION

Herein we describe a case of idiopathic distal RTA discovered during pregnancy. Hypokalemia and metabolic acidosis resolved spontaneously after delivery.

Fetal hyperechoic kidney cohort study and a meta-analysis

Objective: To investigate the positive rate of chromosomal and monogenic etiologies and pregnancy outcomes in fetuses with hyperechoic kidney, and to provide more information for genetic counseling and prognosis evaluation. Methods: We performed a retrospective analysis of 25 cases of hyperechoic kidney diagnosed prenatal in the Second Affiliated Hospital of Harbin Medical University and Harbin Red Cross Central Hospital (January 2017-December 2022). Furthermore, we conducted a meta-analysis of a series of hyperechoic kidneys (HEK) in the literature to assess the incidence of chromosomal and monogenic etiologies, mortality, and pooled odds ratio (OR) estimates of the association between the incidence of these outcomes and other associated ultrasound abnormalities. Results: 25 fetuses of HEK were enrolled in the cohort study, including 14 with isolated hyperechoic kidney (IHK) and 11 with non-isolated hyperechoic kidney (NIHK). Chromosomal aneuploidies were detected in 4 of 20 patients (20%). The detection rate of pathogenic or suspected pathogenic copy number variations (CNVs) was 29% (4/14) for IHK and 37% (4/11) for NIHK. Whole exome sequencing (WES) was performed in 5 fetuses, and pathogenic genes were detected in all of them. The rate of termination of pregnancy was 56% in HEK. 21 studies including 1,178 fetuses were included in the meta-analysis. No case of abnormal chromosome karyotype or (intrauterine death)IUD was reported in fetuses with IHK. In contrast, the positive rate of karyotype in NIHK was 22% and that in HEK was 20%, with the ORs of 0.28 (95% CI 0.16-0.51) and 0.25, (95% CI 0.14-0.44), respectively. The positive rate of (chromosome microarray analysis) CMA in IHK was 59% and that in NIHK was 32%, with the ORs of 1.46 (95% CI 1.33-1.62) and 0.48 (95% CI, 0.28-0.85), respectively. The positive rate of monogenic etiologies in IHK was 31%, with the OR of 0.80 (95% CI 0.25-2.63). In IHK, the termination rate was 21% and neonatal mortality was 13%, with the ORs of 0.26 (95% CI, 0.17-0.40), 1.72 (95% CI, 1.59-1.86), and that in NIHK was 63%, 0.15 (95% CI, 0.10-0.24); 11%, 0.12 (95% CI, 0.06-0.26), respectively. The intrauterine mortality in NIHK group was 2%, with the OR of 0.02 (95% CI, 0.01-0.05). HNF1B variant has the highest incidence (26%) in IHK. Conclusion: The positive rate of karyotype was 20% in HEK and 22% in NIHK. The positive rate of CMA was 32% in NIHK and 59% in IHK. The positive rate of IHK monogenic etiologies was 31%. HNF1B gene variation is the most common cause of IHK. The overall fetal mortality rate of NIHK is significantly higher than that of IHK. The amount of amniotic fluid, kidney size and the degree of corticomedullary differentiation have a great impact on the prognosis, these indicators should be taken into consideration to guide clinical consultation and decision-making.

Effect of Amino Acid Infusion on Amniotic Fluid Index in Pregnancies Associated With Oligohydramnios and Fetal Growth Restriction

Background Oligohydramnios and fetal growth restriction have been known for ages, with increased risk of disease and death during antenatal, neonatal, and adult life leading to operative interventions and perinatal mortality and morbidity. The amniotic fluid index varies with gestational age and is used to detect fetal well-being. Various oral and IV hydration and amino acid infusion therapies are studied to improve amniotic fluid index (AFI) and fetal weight. Objective To study the effect of intravenous amino acid infusion on AFI in pregnancies associated with oligohydramnios and fetal growth restriction (FGR). Material and methods A semi-experimental study done in Acharya Vinoba Bhave Rural Hospital (AVBRH), Sawangi Meghe, Wardha enrolled pregnant women in the in-patient department (IPD) unit of Obstetrics & Gynecology and divided them into two groups of 52 each, which met inclusion and exclusion criteria. Group A received IV amino acid infusion on an alternate day, whereas group B received IV hydration, and serial monitoring was done till delivery. Results The mean gestational age at admission was 32.73 ± 2.21 in the IV amino acid group and 32.25 ± 2.27 in the IV hydration group. In both groups, the mean AFI at admission was observed at 4.93±2.03 cm and 4.22 ± 2.00 cm, respectively. The mean AFI on the 14th day in the IV amino acid group was 7.52 ± 2.04, and in the IV hydration group, 5.89± 2.20 with a significant p-value of <0.0001.

Prenatal diagnosis in the fetal hyperechogenic kidneys: assessment using chromosomal microarray analysis and exome sequencing

Fetal hyperechogenic kidneys (HEK) is etiologically a heterogeneous disorder. The aim of this study was to identify the genetic causes of HEK using prenatal chromosomal microarray analysis (CMA) and exome sequencing (ES). From June 2014 to September 2022, we identified 92 HEK fetuses detected by ultrasound. We reviewed and documented other ultrasound anomalies, microscopic and submicroscopic chromosomal abnormalities, and single gene disorders. We also analyzed the diagnostic yield of CMA and ES and the clinical impact the diagnosis had on pregnancy management. In our cohort, CMA detected 27 pathogenic copy number variations (CNVs) in 25 (25/92, 27.2%) fetuses, with the most common CNV being 17q12 microdeletion syndrome. Among the 26 fetuses who underwent further ES testing, we identified 7 pathogenic/likely pathogenic variants and 8 variants of uncertain significance in 9 genes in 12 fetuses. Four novel variants were first reported herein, expanding the mutational spectra for HEK-related genes. Following counseling, 52 families chose to continue the pregnancy, and in 23 of them, postnatal ultrasound showed no detectable renal abnormalities. Of these 23 cases, 15 had isolated HEK on prenatal ultrasound. Taken together, our study showed a high rate of detectable genetic etiologies in cases with fetal HEK at the levels of chromosomal (aneuploidy), sub-chromosomal (microdeletions/microduplications), and single gene (point mutations). Therefore, we speculate that combined CMA and ES testing for fetal HEK is feasible and has good clinical utility. When no genetic abnormalities are identified, the findings can be transient, especially in the isolated HEK group.

Maternal and neonatal outcomes following induction of labor for fetal growth restriction: Extra-amniotic balloon versus prostaglandins

OBJECTIVE

To compare perinatal outcomes in pregnancies with fetal growth restriction (FGR) undergoing induction of labor by extra-amniotic balloon (EAB) versus prostaglandin E₂ (PGE₂ ).

METHODS

A retrospective cohort study of women with singleton pregnancies and FGR, undergoing induction at term via EAB, PGE₂ , or both, at a single medical center (2014-2017). Primary outcome was rate of cesarean deliveries (CDs). Secondary outcomes included composite maternal and neonatal outcomes.

RESULTS

Overall, 266 women met the inclusion criteria. Among them, 131 (49.2%) underwent induction by PGE₂ , 116 (43.6%) by EAB, and 19 (7.14%) by both methods. No differences were noted in baseline characteristics. Rate of CD (17.24% vs. 6.11% vs. 10.53%, P = 0.022) and maternal composite outcome (18.97% vs. 6.11% vs. 10.53%, P < 0.01) were higher among women who underwent induction by EAB compared with PGE₂ or both. No difference was noted between groups in neonatal outcomes. In a multivariable logistic regression, rates of cesarean delivery and composite maternal outcome were no longer higher in the EAB group (adjusted odds ratio [aOR] 1.68, 95% confidence interval [CI] 0.68-4.16, P = 0.260; and aOR 1.94, 95% CI 0.84-4.45, P = 0.120, respectively).

CONCLUSION

EAB and PGE₂ have comparable maternal and neonatal outcomes when used for induction of labor due to FGR.

Window to the Womb: Amniotic Fluid and Postnatal Outcomes

Amniotic fluid volumes are tightly regulated, and amniotic fluid derangement can indicate maternal complications or fetal abnormalities. Ultrasound estimate of amniotic fluid provides a tool to evaluate the maternal-fetal-placental interface in real-time. Oligohydramnios and polyhydramnios are associated with adverse maternal and neonatal outcomes. Oligohydramnios is associated with adverse maternal and neonatal outcomes including cesarean delivery, operative vaginal delivery, induction of labor, postpartum hemorrhage, small for gestational age neonate, intrauterine demise, neonatal death, NICU admission, and APGAR less than 7 at. 5 minutes of life Polyhydramnios is associated with adverse outcomes including cesarean delivery, induction of labor, placental abruption, shoulder dystocia, cord prolapse, postpartum hemorrhage, intrauterine fetal demise, NICU admission, neonatal death, APGAR less than 7 at 5 minutes of life, large for gestational age neonate, and respiratory distress syndrome. Therefore, Amniotic fluid should be evaluated when maternal or fetal well-being is in question.

Vaginal fluid index - The fifth amniotic pocket

OBJECTIVE

The forebag is a pocket of amniotic fluid preceding the fetal presenting part. Herein we describe the feasibility of transvaginal measurements of the forebag and assess its correlation with the standard amniotic fluid index (AFI).

METHODS

A prospective study was carried out between January 2019 and July 2020. Eligible cases were women with singletons, vertex presentation, and normal AFI at term. We assessed the implementation and acceptance of a novel process in the clinical practice setting. Feasibility was assessed by using transvaginal ultrasound to measure the three orthogonal planes of the forebag. The vaginal fluid index (VFI) was defined as the volume composite of the three orthogonal planes. Correlations of the forebag measurements with both AFI and maximal vertical pocket were then calculated.

RESULTS

In total, 292 out of 305 (95.7%) women were enrolled. All participants completed both transabdominal and transvaginal ultrasound, of which the vaginal pocket was demonstrated in 266 (91.1%) cases. We found significant correlations, in both nulliparas and multiparas, between the vaginal pocket measurements and the VFI to both the AFI and maximal vertical pocket measurements (R = 0.38, P < 0.001; R = 0.3, P < 0.001, respectively).

CONCLUSION

We introduced a new ultrasound variable, the VFI, with a high feasibility rate. This may provide invaluable information for future decision making around the time of delivery.

Moderate-to-Severe Polyhydramnios: Cutoffs for Deepest Vertical Pocket Corresponding to Amniotic Fluid Index

OBJECTIVE

Society for Maternal-fetal medicine Consult Series (#46) states "antenatal fetal surveillance is not required for mild idiopathic" polyhydramnios defined as amniotic fluid index (AFI) of 24 cm or a deepest vertical pocket (DVP) between 8 and 11 cm. The objective of this study was to determine the cutoff for DVP which correlates with AFI ≥ 30 cm.

METHODS

This retrospective study of singleton third trimester ultrasounds included a study group randomly divided into test and validation. In the test group, DVP cutoffs correlating with AFI ≥ 30 cm which was used to define moderate-severe polyhydramnios were calculated in two ways, rounded to the nearest whole number: 1) a receiver operating curve and Youden's J statistic (DVP-Youden) and 2) calculation of the DVP percentile that corresponded with AFI of 30 cm (DVP-Percentile). Using the validation group, diagnostic characteristics were DVP-Youden and DVP-Percentile for diagnosis of AFI ≥ 30 cm and were compared against SMFM cutoffs (DVP-SMFM).

RESULTS

Seventy one thousand eight hundred and ninety three ultrasound exams in the 3rd trimester had assessment of AFI and DVP. Moderate-severe polyhydramnios occurred in 286 (1.2%) in test group and 571 (1.2%) in validation group. AFI of 30 cm corresponded to the 98.9th percentile, which in turn correlated to a DVP of 10 cm (DVP-Percentile). The calculated cutoff for moderate-severe polyhydramnios was 8 cm for DVP-Youden.

CONCLUSION

Using 8.0 cm rather than 12.0 cm increased the detection of moderate-severe polyhydramnios to 100% with a false positive rate under 5%. For those utilizing DVP for amniotic fluid evaluation, identification of a DVP ≥ 8.0 cm should prompt further evaluation with complete AFI.

Tubular and glomerular biomarkers of renal tissue function in the urine of fetuses with posterior urethral valves

INTRODUCTION

Posterior urethral valve (PUV) is a congenital malformation characterized by a membranous structure located in the prostatic portion of the male posterior urethra that obstructs the urinary flow. Efforts have been made to determine the degree of impairment of fetal kidney function in this condition.

OBJECTIVE

This study aimed to measure the levels of urinary biomarkers of glomerular and tubular functions in fetuses with PUV and to compare with the levels of the same molecules in healthy male premature newborns.

STUDY DESIGN

Urine samples from 43 fetuses with PUVs were collected and compared with urine samples from 40 healthy male newborns of the same gestational age (controls). Tubular and glomerular biomarkers levels were measured in urine samples by MILLIPLEX® assay kits. Levels of the molecules were related to creatinine (Cr) measurements at same urine samples and expressed as pg/mg Cr. Results were analysed with Graphpad Prism version 7.0 and SPSS version 20.0.

RESULTS

Fetuses with PUV showed a significant reduction in urine levels of Epidermal Growth Factor (EGF), Calbindin, Osteoactivin, Molecule Renal Injury 1 (KIM-1 and Factor of trefoil 3 (TFF-3) when compared to controls. On the other hand, urine levels of cystatin C and renin were higher in PUV fetuses. The levels of molecules also differed according to urine osmolality and grade of hydronephrosis.

DISCUSSION

Some urinary excreted molecules may indicate kidney damage in several segments along the nephron, while others may exert important functions. Mechanical and immunological mechanisms related to PUV might significantly modulate the synthesis of cytokines related to glomerular and tubular physiology, leading to alterations in urinary concentrations of those molecules. These biomarkers can be used as future diagnostic and prognostic markers in clinical practice.

CONCLUSION

Early kidney structural and functional impairment influenced the synthesis of glomerular and tubular molecules related to kidney physiological processes in fetuses with PUV.

Predicting Factors of Protracted Intestinal Failure in Children with Gastroschisis

OBJECTIVE

To identify prenatal and neonatal predictors of short bowel syndrome-related intestinal failure (SBS-IF) in gastroschisis.

STUDY DESIGN

This retrospective study included all patients with gastroschisis born between 2000 and 2017 who were enrolled in our home parenteral nutrition program, and all patients with gastroschisis born in our institution who survived 2 weeks, during the same time period. Prenatal ultrasound features, neonatal status, anatomic features, oral feeding, and parenteral nutrition dependency were analyzed.

RESULTS

Among 180 patients, 35 required long-term parenteral nutrition (SBS-IF group) and 145 acquired full oral feeding within 6 months (oral feeding group). The mean follow-up was 7.9 years (IQR, 1.6-17.5 years) and 5.0 years (IQR, 0.1-18.2 years), respectively. Both bowel matting (OR, 14.23; 1.07-16.7; P = .039) and secondarily diagnosed atresia or stenosis (OR, 17.78; 3.13-100.98; P = .001) were independent postnatal predictors of SBS-IF. Eighteen children (51% of the SBS-IF group) were still dependent on artificial nutrition at the last follow-up. patients with SBS-IF who achieved full oral feeding had a median residual small-bowel length of 74 cm (IQR, 51-160 cm) vs 44 cm (IQR, 10-105 cm) for those still dependent on artificial nutrition (P = .02). An initial residual small bowel length of more than 50 cm was the best predictive cut-off for nutritional autonomy, with a sensitivity of 67% and a specificity of 100%.

CONCLUSIONS

Bowel matting, complex gastroschisis, and secondary intestinal obstruction were associated with SBS-IF in gastroschisis. For patients with SBS-IF, a small bowel length of more than 50 cm was predictive of secondary nutritional autonomy.

Semiquantitative Assessment of Amniotic Fluid Among Individuals With and Without Diabetes Mellitus

OBJECTIVE

To compare the rate and severity of abnormal amniotic fluid volumes (oligohydramnios or polyhydramnios), as well as the distribution of amniotic fluid levels, in pregnancies with and without diabetes.

METHODS

We performed a retrospective cohort study of singleton nonanomalous pregnancies receiving an ultrasound examination (USE) in the third trimester. Pregnancies were categorized into those with and without diabetes and subcategorized by diabetes type. The primary outcomes were oligohydramnios or polyhydramnios. Polyhydramnios was also examined by severity. The association between maternal diabetes status and oligohydramnios or polyhydramnios was assessed using logistic regression. In addition, we computed gestational age-specific amniotic fluid index (AFI) and deepest vertical pocket (DVP) centiles for pregnancies with and without diabetes.

RESULTS

There were 60,226 USEs from 26,651 pregnancies that met inclusion criteria. There were 3992 (15.0%) pregnancies with diabetes and 22,659 (85.0%) without diabetes. Using AFI, the rate of polyhydramnios was 10.5 versus 3.8% (odds ratio [OR] 2.95; 95% confidence interval [CI] 2.62-3.32) for pregnancies with versus without diabetes, respectively; using DVP, the rate of polyhydramnios was 13.9 versus 5.4% (OR 2.84; 95% CI 2.56-3.15). Rates of oligohydramnios were also increased in pregnancies with diabetes (3.3 versus 2.6%; OR 1.26; 95% CI 1.04-1.52). The AFI and DVP were significantly higher in the cohort with diabetes between 28 and 36 weeks.

CONCLUSION

Within our study population, pregnancies with diabetes had increased rates of oligohydramnios and polyhydramnios as well as increased gestational age-specific amniotic fluid volumes between 28 and 36 weeks. A higher prevalence of polyhydramnios was observed using DVP as compared to AFI; nevertheless, associations were similar using either method.

Amniotic Fluid Volume Estimation from 20 Weeks to 28 Weeks. Do You Measure Perpendicular to the Floor or Perpendicular to the Uterine Contour?

OBJECTIVE

Two different techniques are described in the literature for measuring amniotic fluid pockets to estimate amniotic fluid volume. This study was undertaken to determine if ultrasound estimates using amniotic fluid index (AFI) and single deepest pocket (SDP) techniques should be measured perpendicular to floor vs perpendicular to uterine contour in pregnancies between 20 and 28 weeks.

STUDY DESIGN

Amniotic fluid was measured using AFI and SDP techniques in low risk pregnant women undergoing an indicated ultrasound between 20 and 28 weeks of gestation. Measurements of both AFI and SDP were made holding the ultrasound transducer perpendicular to the floor and then perpendicular to the uterine contour. Pearson's correlation coefficient was used to assess the association between estimated amniotic fluid volumes determined by the transducer perpendicular to the floor versus transducer perpendicular to the uterine contour; intra-class correlation coefficient was used to test agreement of the two techniques.

RESULTS

Measurements were collected on 160 women between 20 and 28 weeks. For pregnancies between 20 and 28 weeks, the level of correlation for AFI was 0.67 (95% CI 0.57-0.74) [moderate] and for SDP was 0.47 (95% CI: 0.34-0.58) [poor].

CONCLUSION

In pregnancies between 20 and 28 weeks, the correlation of AFI values perpendicular to floor and perpendicular to the uterine contour remains moderate, either measurement can be used to estimate amniotic fluid volume. The correlation for SDP is poor and it remains uncertain which technique, perpendicular to floor or perpendicular to uterine contour, should be used for estimating amniotic fluid volume.

Prenatal diagnosis of auriculocondylar syndrome with a novel missense variant of GNAI3: a case report

BACKGROUND

Auriculocondylar syndrome (ACS) is a rare disorder characterized by micrognathia, mandibular condyle hypoplasia, and auricular abnormalities. Only 6 pathogenic variants of GNAI3 have been identified associated with ACS so far. Here, we report a case of prenatal genetic diagnosis of ACS carrying a novel GNAI3 variant.

CASE PRESENTATION

A woman with 30 weeks of gestation was referred to genetic counseling for polyhydramnios and fetal craniofacial anomaly. Severe micrognathia and mandibular hypoplasia were identified on ultrasonography. The mandibular length was 2.4 cm, which was markedly smaller than the 95th percentile. The ears were low-set with no cleft or notching between the lobe and helix. The face was round with prominent cheeks. Whole-exome sequencing identified a novel de novo missense variant of c.140G > A in the GNAI3 gene. This mutation caused an amino acid substitution of p.Ser47Asn in the highly conserved G1 motif, which was predicted to impair the guanine nucleotide-binding function. All ACS cases with GNAI3 mutations were literature reviewed, revealing female-dominated severe cases and right-side-prone deformities.

CONCLUSION

Severe micrognathia and mandibular hypoplasia accompanied by polyhydramnios are prenatal indicators of ACS. We expanded the mutation spectrum of GNAI3 and summarized clinical features to promote awareness of ACS.

Contemporary experience of polyhydramnios: A single-centre experience

Introduction

Polyhydramnios is common; the majority of cases are idiopathic, but maybe associated with fetal abnormality. Literature suggests the volume of amniotic fluid discriminates idiopathic from pathological polyhydramnios but is not unanimous. We assessed fetal anomaly incidence amongst women with polyhydramnios and the role of discriminatory variables in identifying pathological cases.

Methods

Retrospective observational cohort study at an inner‐city London fetal medicine centre. Records for patients referred and/or diagnosed with polyhydramnios were reviewed as well as maternal/fetal demographics, amongst singleton pregnancies using the Astraia™ database from January 2015–2016. Estimated fetal weight was calculated using the Hadlock model (biometry undertaken at diagnosis). Student's t‐test/one‐way ANOVA compared means; chi‐squared tests compared proportions.

Results

120 cases were identified. 36 (30%) had fetal abnormality. There was no difference in AFI between fetuses with an abnormality and without (26.7 vs 25.2 cm, P = 0.22). AFI was normalised for weight (AFI (cm)/estimated fetal weight (kg)): AFI/kg was significantly different between cases with fetal abnormality and without (24.4 vs 16.7 cm/kg, P < 0.001) – incidence of abnormality increased with increasing AFI/kg (P = 0.007). Early gestational diagnosis was associated with higher rates of anomaly (P = 0.004). Differences in AFI/kg between those with and without abnormality were not significant when adjusted for gestation. AFI was significantly higher in cases of abnormality diagnosed at later gestation (P = 0.005).

Conclusion

Excess volume of amniotic fluid alone does not denote abnormality. Earlier gestations and higher AFI/kg corresponded with significantly increased rates of anomaly. However, the latter is a result of confounding by gestation, which is closely correlated with fetal weight.

Changes in placental elastography in the third trimester - Analysis using a linear mixed effect model

INTRODUCTION

Research into the role of ultrasound elastography to assess compromised placental tissue is ongoing. There is particular interest in evaluating its potential in the investigation of changes associated with uteroplacental dysfunction. To date, there is limited data on how different maternal and fetal considerations, such as advancing gestational age, amniotic fluid Index (AFI) and maternal body mass index (BMI) may influence shear wave velocity (SWV) measurements. This study aimed to evaluate longitudinal changes in SWV throughout gestation and model these changes with other developing fetal and maternal physiological and biological characteristics.

METHODS

The study utilised 238 singleton pregnancies and collected longitudinal data at repeated intervals in the 3rd trimester representing 629 individual data points. Linear mixed model regression analysis was used to identify significant predictors for SWV.

RESULTS

From a total of ten variables selected for modelling, only gestational age, AFI, BMI, and sample depth were found to be significant predictors of placental SWV, and gestational age and AFI were found to have only a minimal impact on SWV.

DISCUSSION

Sophisticated statistical modelling demonstrates that many of the expected maternal and fetal changes in the 3rd trimester have no or minimal impact on placental SWV. Understanding which factors influence placental SWV is essential to ascertain the technique's utility in managing pregnancies complicated by placental dysfunction in the future.

Does the Summer Season Affect the Amniotic Fluid Volume during Pregnancy?

Amniotic fluid is crucial for the well-being of the fetus. Recent studies suggest that dehydration in a pregnant woman leads to oligohydramnios. We assessed the variation in the amniotic fluid index (AFI) during the summer and non-summer seasons and evaluated neonatal outcomes. We retrospectively reviewed electrical medical records of pregnant women who visited the Konkuk University Medical Center for antenatal care, between July 2005 and July 2019. A total of 19,724 cases from 6438 singleton pregnant women were included after excluding unsuitable cases. All AFI values were classified as 2nd and 3rd trimester values. Additionally, borderline oligohydramnios (AFI, 5–8) and normal AFI (AFI, 8–24) were assessed according to the seasons. The average AFI between the summer and non-summer season was statistically different only in the 3rd trimester; but the results were not clinically significant. In the 3rd trimester, the summer season influenced the increased incidence of borderline oligohydramnios. The borderline oligohydramnios group showed an increased small-for-gestational-age (SGA) rate and NICU admission rate. In the summer season, the incidence of borderline oligohydramnios was seen to increase. This result would be significant for both physicians and pregnant women.

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.

Perinatal and infant outcome of fetuses with prenatally diagnosed hyperechogenic kidneys

OBJECTIVE

Hyperechogenic kidneys are a relatively rare antenatal finding, which can generate significant parental anxiety due to uncertain prognosis. We report on the perinatal and infant outcomes of a large cohort of fetuses with antenatally diagnosed hyperechogenic kidneys.

METHODS

This was a retrospective analysis of all cases diagnosed prenatally with hyperechogenic kidneys between 2002 and 2017 in a large tertiary fetal medicine unit. Hyperechogenicity was defined as kidney parenchyma with greater echogenicity than that of the liver. Pregnancy, pathological and postnatal outcomes were collected from hospital and general practitioner records up to 1 year of age. Abnormal renal outcome was defined as elevated creatinine beyond 6 months of age, hypertension requiring medication or major kidney surgery, such as nephrectomy. Severe abnormal renal outcome was defined as the need for dialysis or kidney transplant at any stage.

RESULTS

Three-hundred and sixteen fetuses with hyperechogenic kidneys were identified at a mean gestational age of 21 (range, 13-37) weeks. The majority of cases (97%) had bilateral hyperechogenic kidneys. In the 265 cases with available follow-up data, other associated renal tract abnormalities were identified prenatally in 36%, concomitant extrarenal structural abnormalities in 39% and abnormal karyotype in 15% of cases. Of the 316 included cases, 139 did not survive, including 105 terminations of pregnancy, five intrauterine deaths and 29 early neonatal deaths. Only 4.3% (6/139) of these fetuses had isolated hyperechogenic kidneys while 28.1% (39/139) had associated multiple renal tract abnormalities alongside hyperechogenic kidneys and over two-thirds (67.6%; 94/139) had concomitant extrarenal abnormalities. Of the 177 cases that survived beyond 1 month of age, outcome data were available in 126. Of these, based on the antenatal findings, 60 (47.6%) cases had isolated hyperechogenic kidneys, 56 (44.4%) had associated renal structural abnormalities and 10 (7.9%) had additional extrarenal abnormalities. Considering renal outcome alone, kidney function was abnormal in 13 (21.7%), 10 (17.9%) and 0 (0%) infants in these three groups, respectively, although concurrent pathology clearly affected global outcome in the more complex cases. Neonatal mortality of 1.6% was observed in the isolated renal hyperechogenicity group. The presence of oligohydramnios or abnormal renal volume was not associated significantly with abnormal renal function (odds ratio (OR), 2.32 (99% CI, 0.54-10.02) and OR, 0.74 (99% CI, 0.21-2.59), respectively) in this group.

CONCLUSIONS

Hyperechogenic kidneys are often complicated by associated renal tract and extrarenal abnormalities, aberrant karyotype and genetic disease, and these factors have a greater effect on overall outcome than does kidney echogenicity. The renal outcome of fetuses with isolated hyperechogenic kidneys is good generally, with over 70% of cases having normal renal function postpartum. Importantly, for prognostic counseling, all of the fetuses in this non-selected series with isolated hyperechogenic kidneys and normal amniotic fluid levels had normal renal outcome in infancy. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Hourly fetal urine production rate in isolated oligohydramnios at term

Objective

The aim of this study was to evaluate the hourly fetal urine production rate (HFUPR) via three-dimensional ultrasonography in women with isolated oligohydramnios and compare with normal pregnant women at term.

Materials and methods

This was a prospective observational cohort study of 112 women from 34 to 40 6/7 weeks’ gestation. They were classified into three groups according to the amniotic fluid index (AFI) and ultrasonographic estimated fetal weight (EFW) as isolated oligohydramnios (defined as AFI below 5% and appropriate EFW corresponding to gestational age) (n = 34) and IUGR (defined as EFW below 5% corresponding to gestational age irrespective amniotic fluid) (n = 17), and normal pregnancy (n = 61). HFUPR was measured using three-dimensional virtual organ computer-aided analysis. Adverse perinatal outcomes in all participants were examined.

Results

There was no significant difference in HFUPR between patients with isolated oligohydramnios and women with normal pregnancies (median, 40.0 mL/h [interquartile range [IQR] 31.0–66.5] vs. 48.6 [31.5–81.2], p = 0.224). HFUPR was significantly decreased in the IUGR group (13.8 mL/h [IQR 10.1–24.8]), compared to the normal pregnancy group (p<0.001) and the isolated oligohydramnios group (p<0.001). HFUPR was significantly decreased in neonates with adverse perinatal outcomes compared to the control (24.7 mL/h [IQR 13.4–47.4] vs. 43.6 [29.8–79.0], p = 0.016).

Conclusion

HFUPR was not decreased in patients with isolated oligohydramnios but was decreased in patients with IUGR when compared to normal controls at term.

Novel scoring system for determining fetal candidacy for prenatal intervention for severe congenital lower urinary tract obstruction

OBJECTIVES

To evaluate a novel scoring system that combines several prenatal parameters for selecting ideal candidates for fetal intervention, and for predicting postnatal survival in patients with severe fetal lower urinary tract obstruction (LUTO).

METHODS

We retrospectively reviewed all cases of severe LUTO evaluated for fetal intervention in a single large fetal center between January 2013 and December 2017. A scoring system for determining fetal candidacy for intervention was retrospectively developed based on postnatal outcomes. The proposed scoring system included fetal urinary biochemistry, renal ultrasound parameters, initial bladder volume, and degree of bladder refill. Relevant demographic characteristics, ultrasound reports and laboratory results were reviewed. Receiver operating characteristic (ROC) curves were used to select the cut-off values for initial bladder volume and degree of bladder refill and to evaluate the performance of the scoring system in predicting postnatal death.

RESULTS

Of the 79 LUTO patients evaluated, 31 were eligible for the study. The overall 6-month postnatal survival was 64.5 % (20/31). A scoring system (0-8) was suggested with 2 points for unfavorable biochemistry, 4 points for ultrasound evidence of dysplastic kidneys, 1 point for inadequate initial bladder volume and 1 point for inadequate bladder refill. Scores>3 (N = 7) were associated with 0 % 6-month survival. The ROC curve for predicting postnatal mortality showed area under curve (AUC) of 0.82 (95 % CI 0.65-0.99). Subgroup analysis within subjects who underwent fetal intervention (N = 22) also confirmed the significance of the distribution of the scoring system between groups who survived and those who did not after adjustment for GA at delivery (p = 0.01).

CONCLUSION

We propose a novel scoring system for antenatal evaluation of patients with severe LUTO which may be useful in selecting those candidates most appropriate for intervention and in counseling parents about predicted postnatal outcome.

Twelve Live Births After Uterus Transplantation in the Dallas UtErus Transplant Study

OBJECTIVE

To describe aggregated pregnancy outcomes after uterus transplantation from a single, experienced center.

METHODS

This prospective study reports on live births among 20 women who received a uterus transplant from 2016 to 2019 at Baylor University Medical Center at Dallas. These live births occurred between November 2017 and September 2020. The main measures were live birth, maternal complications, and fetal and newborn outcomes.

RESULTS

There were six graft failures (four surgical complications and two with poor perfusion postoperatively). Of the 14 technically successful transplants, at least one live birth occurred in 11 patients. Thus far, the live birth rate per attempted transplant is 55%, and the live-birth rate per technically successful transplant is 79%. Ten uteri were from nondirected living donors and one uterus was from a deceased donor. In vitro fertilization was performed to achieve pregnancy. Ten recipients delivered one neonate, and one recipient delivered two neonates. One organ rejection episode was detected during pregnancy and was resolved with steroids. The median birth weight was 2,890 g (range 1,770-3,140 g [median 68th percentile]). Maternal weight gain was higher than Institute of Medicine recommendations. Maternal medical complications were observed in five recipients (elevated creatinine level, gestational diabetes, gestational hypertension [n=2], and preeclampsia). In five recipients, maternal medical or obstetric complications led to an unplanned preterm delivery (elevated creatinine level, preeclampsia; preterm labor [n=3]). The median gestational age at delivery was 36 6/7 weeks (range 30 6/7-38 weeks). All neonates were liveborn, with Apgar scores of 8 or higher at 5 minutes.

CONCLUSION

Over the first 3 years, our program experienced a live-birth rate per attempted transplant of 55% and a live-birth rate per technically successful transplant of 79%. In our experience, uterus transplantation resulted in a third-trimester live birth in all cases in which pregnancies reached 20 weeks of gestation. Maternal medical and obstetric complications can occur; however, these were manageable by applying principles of generally accepted obstetric practice.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02656550.

Fetoscopic urethral meatotomy in fetuses with lower urinary tract obstruction by congenital megalourethra

BACKGROUND

To describe the perinatal outcomes of fetoscopic urethral meatotomy (FUM) in fetuses with lower urinary tract obstruction (LUTO) by congenital megalourethra.

STUDY DESIGN

Between 2012 and 2020, 226 cases with LUTO were referred to our fetal surgery center in Queretaro, Mexico. We report the perinatal outcome of cases with LUTO by congenital megalourethra that were selected for FUM in an attempt to release the penile urethral obstruction.

RESULTS

Congenital megalourethra was diagnosed in 10 cases (4.4%) but only 3 cases (30%) with obstructive megalourethra and megacystis were selected for fetal surgery. Fetoscopic urethral metatotomy was successfully performed in all three cases at a median gestational age (GA) of 21.4 (18.0-26.7) weeks and with a median surgical time of 27 (12-43) min. A resolution of urethral dilatation and subsequent reduction of the penile length and normalization of both the bladder size and amniotic fluid were observed in all cases. The median GA at delivery was 35.2 (range: 30.6-38.0) weeks. There were no fetal deaths but one neonatal death (33%) secondary to renal failure and preterm delivery.

CONCLUSION

In fetuses with LUTO by congenital obstructive megalourethra, FUM is feasible and is associated with good perinatal outcomes.

A Rare Cause of Refractory Severe Polyhydramnios: Antenatal Bartter Syndrome

Background: Antenatal Bartter syndrome is an autosomal recessive disorder causing severe polyuria that leads to severe polyhydramnios and preterm labor. Prenatal diagnosis of antenatal Bartter syndrome is difficult because the genetic diagnosis can only be confirmed following a clinical diagnosis in infants. Reports of prenatal diagnosis and treatment of antenatal Bartter syndrome are limited. Case Presentation: We present the case of a 33-year-old pregnant woman with refractory polyhydramnios at 31 weeks of gestation. There were no structural anomalies or placental problems on ultrasonography; therefore, antenatal Bartter syndrome was suspected. With repeated amniocentesis and indomethacin therapy, the pregnancy continued to 36 weeks of gestation. The clinical features of the infant and subsequent genetic testing confirmed the diagnosis of antenatal Bartter syndrome. The baby was in good clinical condition at the 3-month follow-up visit. Conclusions: For pregnant women with early onset and refractory severe polyhydramnios without morphological anomalies, antenatal Bartter syndrome should be highly suspected.

Oligohydramnios: how severe is severe?

OBJECTIVE

To investigate whether the severity of isolated oligohydramnios at term is associated with increased rates of adverse perinatal outcome.

STUDY DESIGN

A retrospective study conducted in a single medical center from 2017 to 2019. All low-risk pregnancies with incidental isolated oligohydramnios at term were included. The degree of oligohydramnios was arbitrarily classified into mild (AFI = 41-50 mm), moderate (AFI = 21-40 mm) and severe (AFI = 0-20 mm).

RESULT

A total of 610 women were included: 202 with a mild (33.1%), 287 moderate (47.0%), and 121 severe oligohydramnios (19.8%). Non-reassuring monitor requiring immediate delivery and worse composite neonatal outcome were more common among severe than mild or moderate oligohydramnios (14.0% and 6.4%, 7.3% respectively; p = .039 and 19.8%, 10.9% and 11.8%, respectively; p = .048).

CONCLUSION

Low-risk pregnancies with isolated severe oligohydramnios at term have a higher tendency toward non-reassuring fetal monitoring requiring prompt delivery and adverse neonatal outcomes, this calls for close intrapartum surveillance.

The effect of polyhydramnios degree on chromosomal microarray results: a retrospective cohort analysis of 742 singleton pregnancies

PURPOSE

To analyze the risk for clinically significant microarray aberrations in pregnancies with polyhydramnios.

METHODS

Data from all chromosomal microarray analyses (CMA) performed due to polyhydramnios between January 2013 and December 2019 were retrospectively obtained from the Ministry of Health Database. The rate of clinically significant (pathogenic and likely pathogenic) CMA findings in isolated and non-isolated polyhydramnios cohorts was compared to a local control group of 5541 fetuses with normal ultrasound, in which 78 (1.4%) abnormal results were demonstrated. Subgroup analyses were performed by the degree of polyhydramnios, week of diagnosis, maternal age, and the presence of additional sonographic anomalies.

RESULTS

In the isolated polyhydramnios cohort, 19/623 (3.1%) clinically significant CMA aberrations were noted, a significantly higher rate compared to the control population. However, the risk for abnormal CMA results in the 158 cases with mild polyhydramnios (AFI 25-29.9, or maximal vertical pocket 8-11.9 cm) did not significantly differ from pregnancies with normal ultrasound. Of 119 cases of non-isolated polyhydramnios (most frequently associated with cardiovascular (26.1%) and brain (15.1%) anomalies), 8 (6.7%) abnormal CMA findings were noted, mainly karyotype-detectable.

CONCLUSION

Mild polyhydramnios was not associated with an increased rate of clinically significant microarray results, compared to pregnancies with normal ultrasound. An extensive anatomical sonographic survey should be performed in pregnancies with polyhydramnios, with consideration of fetal echocardiography.

Pregnant women infected by the Zika virus: Ultrasound findings and growth patterns of fetuses with and without microcephaly

OBJECTIVE

To compare ultrasound growth measurements of fetuses with and without microcephaly in suspected Zika virus infection.

METHODS

A retrospective cohort study included pregnant women with suspected Zika virus infection to evaluate 110 fetuses with and without microcephaly. The women had been admitted to the fetal medicine unit between October 2015 and August 2016. Cases of fetal microcephaly resulting from other causes were excluded. Variables evaluated were the ultrasound measurements taken at fetal biometry. The relation between each fetal biometry measurement and gestational age was analyzed using fractional polynomials in random-effects regression models. To evaluate fetal growth, curves of the mean fetal biometric parameters were constructed as a function of gestational age.

RESULTS

Mean biparietal diameter and mean head circumference increased in both groups as a function of gestational age. In the group with fetal microcephaly, mean head circumference was significantly larger in the 13th and 14th weeks of pregnancy, becoming smaller compared with the group without microcephaly from the 20th week onwards, with the difference increasing with gestational age.

CONCLUSION

Fetal head circumference continues to increase until birth, even after a diagnosis of microcephaly, with a reduction only in the pace of growth. Growth decelerates as the pregnancy approaches term.

Amniotic fluid index curves in the obese gravida

OBJECTIVE

To determine whether amniotic fluid volume as measured by amniotic fluid index (AFI) is influenced by maternal pre-gestational obesity as measured by body mass index (BMI).

METHODS

This was a retrospective cohort study of pregnant women between 20 and 43 weeks gestation receiving ultrasounds with AFI measurements at Augusta University Medical Center between 2003 and 2017. A subset of 500 charts that met inclusion and exclusion criteria were reviewed to obtain maternal clinical data. The study cohort was subdivided by maternal BMI at initial obstetric visit into three groups: normal weight (18.5 kg/m2-24.9 kg/m2), overweight (25.0 kg/m2-29.9 kg/m2), and obese (≥ 30 kg/m2). Chi-square analysis was used to compare BMI groups in terms of categorical clinical characteristics and outcome variables, and analysis of variance (ANOVA) was used for continuous variables. Mixed effects regression models (MRMs) were used to evaluate AFI throughout gestation separately in each group, and MRM-based analysis of covariance was used to compare AFI throughout gestation among groups. AFI curves were constructed for the 5th, 50th, and 95th percentiles for all study subjects combined and separately for normal weight, overweight, and obese subjects.

RESULTS

Fitted curves relating AFI percentiles to estimated gestational age (EGA) showed statistically significant differences among BMI groups. There was also a significant difference in AFI over gestation across the obesity groups.

CONCLUSION

Fitted curves for AFI throughout pregnancy showed statistically significant differences among BMI groups.

Automated ultrasound assessment of amniotic fluid index using deep learning

The estimation of antenatal amniotic fluid (AF) volume (AFV) is important as it offers crucial information about fetal development, fetal well-being, and perinatal prognosis. However, AFV measurement is cumbersome and patient specific. Moreover, it is heavily sonographer-dependent, with measurement accuracy varying greatly depending on the sonographer's experience. Therefore, the development of accurate, robust, and adoptable methods to evaluate AFV is highly desirable. In this regard, automation is expected to reduce user-based variability and workload of sonographers. However, automating AFV measurement is very challenging, because accurate detection of AF pockets is difficult owing to various confusing factors, such as reverberation artifact, AF mimicking region and floating matter. Furthermore, AF pocket exhibits an unspecified variety of shapes and sizes, and ultrasound images often show missing or incomplete structural boundaries. To overcome the abovementioned difficulties, we develop a hierarchical deep-learning-based method, which consider clinicians' anatomical-knowledge-based approaches. The key step is the segmentation of the AF pocket using our proposed deep learning network, AF-net. AF-net is a variation of U-net combined with three complementary concepts - atrous convolution, multi-scale side-input layer, and side-output layer. The experimental results demonstrate that the proposed method provides a measurement of the amniotic fluid index (AFI) that is as robust and precise as the results from clinicians. The proposed method achieved a Dice similarity of 0.877±0.086 for AF segmentation and achieved a mean absolute error of 2.666±2.986 and mean relative error of 0.018±0.023 for AFI value. To the best of our knowledge, our method, for the first time, provides an automated measurement of AFI.

Nomogram to predict the risk of preterm birth before 37 weeks and 34 weeks in pregnant women with a short cervix

OBJECTIVES

This study investigated the potential factors that predict the risk of preterm birth (PTB) in pregnancies with a short cervix. These factors were used to create nomogram, which might be highly sensitive tools to predict the incidence of PTB.

METHODS

This retrospective cohort study enrolled pregnancies with a short cervix from 1 January 2017 to 1 January 2018. The primary outcomes were preterm birth <37 and 34 weeks. Logistic regression model was used to identify potential predictors of PTB. The identified risk factors were used to establish nomograms, which were validated using the receiver operating characteristic (ROC) curve and calibration curve.

RESULTS

In the multivariate analysis, overweight or obesity, parity ≧3 times, twin pregnancy, in vitro fertilization and embryo transfer (IVF-ET), gestational age at first observation of short cervix, cervical length (CL) at first observation of short cervix, history of PTB, and autoimmune disease were found to be predictors of PTB <37 weeks, while twin pregnancy, gestational age at first observation of short cervix, CL of short cervix, history of PTB, and prepregnancy hypertension were predictors of PTB <34 weeks. The area under the ROC curve of the nomogram predicting PTB <37 weeks and PTB <34 weeks were 0.803 and 0.771, respectively. Both models showed good discrimination.

CONCLUSIONS

Gestational age at first observation of short cervix, CL of short cervix and other factors are strong predictors of PTB in pregnancies with a short cervix. Both nomograms showed good discrimination and calibration, and hence might be effective in predicting PTB for this population.

Development of the Z-score for the measurement of myocardial thickness by two-dimensional echocardiography in normal fetuses

BACKGROUND

In the current literature, there is a tendency to describe normal values of echocardiographic measurements by means of the Z-score. In fetal cardiology, these Z-score equations are still being established. Measurement of myocardial thickness is an important assessment, especially in fetuses of diabetic mothers, because of the risk of developing myocardial hypertrophy secondary to elevated maternal blood glucose levels.

OBJECTIVE

To determine the percentiles and to develop the Z-score equations of right and left ventricular lateral walls and interventricular septum measurements using two-dimensional echocardiography in normal fetuses between 24 and 34 weeks of gestation.

METHODS

This is a prospective cross-sectional study that was performed in single fetuses with normal heart from nondiabetic pregnant women. Measurements of the lateral walls of the right and left ventricles and the interventricular septum were made.

RESULTS

Eight hundred and seventy three pregnant women were included. We determined the percentiles of the measurements for each gestational age. The Z-score equation was developed for each of the measurements: right ventricular lateral wall measurement [RVLW = x-(-1 + 0.109 * GA)/0.4], left ventricle lateral wall measurement [LVLW = x-(-1.366 + 0.12 * GA)/0.43], and interventricular septum, both at the four-chamber view [IVS_4ch = (x-(-1.113 + 0.107 * GA)/0.4] and at the left ventricular outflow tract plane [IVS_LVOT = (x-(-0.581 + 0.084 * GA)/0.35].

CONCLUSION

The present study allowed the demonstration of the percentiles and the Z-score equations for each of the measurements studied.

Is chlorine and sodium levels in the amniotic fluid a new marker for fetal lung maturation and RDS severity?

BACKGROUND

Amniotic fluid (AF) is a dynamic liquid whose contents vary according to the needs of the fetus. Levels of the amniotic components have been used in numerous studies as potential biomarkers to screen pregnancy-related abnormalities. As a reflection of Na⁺ and Cl^- levels of fetal lung fluid, amniotic fluid's Na⁺ and Cl^- levels can be used as an indicator of lung maturation in the newborn period. This study aimed to investigate whether Na⁺ and Cl^- levels in the amniotic fluid would be a new marker to determine the severity of respiratory distress and pulmonary maturation in the newborn.

METHODS

This prospective cohort study was conducted at Hacettepe University Neonatal Intensive Care Unit. One hundred twenty single infants who were delivered with the cesarean section between January 2015 and March 2016 were included. Na⁺ and Cl^- levels were measured from AF.

RESULTS

There were 46 of 120 infants (33.3%) in Group-1 and 74 infants (66.7%) in Group-2. Na + and Cl^- levels of the AF of Group-1 were higher than Group 2 and this was statistically significant (p < .001/p: .01, respectively). Na⁺ and Cl^- levels of the AF were significantly higher in infants who needed surfactant (p < .001/p: .001, respectively).

CONCLUSION

Our results showed that Na⁺ and Cl^- levels of the AF can be used as an indicator of infant lung maturation.

Current perspective and scope of fetal therapy: part 2

Fetal therapy has been defined as any therapeutic intervention either invasive or noninvasive for correcting or treating any fetal malformation or condition. Invasive fetal therapy have its own set of maternal and fetal complications and invasive approach is not feasible in many of fetal conditions that are candidate for fetal therapy. Many such fetal conditions have been treated successfully by medical or noninvasive management. In medical fetal therapy, mothers are treated with medications which are transferred to fetus through placenta and exert positive effect on the fetus, thus avoiding complications that are seen secondary to invasive fetal therapy. The fetal conditions that have been managed with medical therapy includes fetal and neonatal alloimmune thrombocytopenia, neural tube defect, congenital adrenal hyperplasia, perinatal infections, respiratory distress syndrome, inborn error of metabolism, and congenital cystic adenomatoid malformation. This review will cover the medical or noninvasive aspect of fetal therapy and will highlight the progress made in the management of these fetal conditions.

<p>What is the Impact of Abnormal Amniotic Fluid Volumes on Perinatal Outcomes in Normal Compared with At-Risk Pregnancies?</p>

Objective

Assessing amniotic fluid volume is an integral part of obstetric practice. Data are sparse on at-risk pregnancy and amniotic fluid volumes. The aim of our study was to determine if there is a difference in perinatal outcomes based on complications of pregnancy and amniotic fluid volumes. We hypothesized that at-risk pregnancies with abnormal amniotic fluid volumes would have worse perinatal outcomes than normal pregnancies with abnormal amniotic fluid volumes.

Study Design

This retrospective cohort study evaluated both normal and at-risk singleton pregnancies with intact membranes on admission for delivery. Amniotic fluid volumes were estimated using both the amniotic fluid index (AFI) and single deepest pocket (SDP) techniques. All sonograms were performed by trained ultrasound technicians or obstetrician/gynecologists. We placed 3365 women into 6 separate groups (at-risk versus normal, then further stratified by oligohydramnios by SDP, normal fluid, or polyhydramnios by AFI).

Results

At-risk pregnancies with normal fluid and at-risk pregnancies with polyhydramnios have significantly increased risk of neonatal intensive care unit (NICU) admission [OR 2.06 (95% CI 1.63,2.60), OR 2.74 (95% CI 1.54, 4.87)]. Birthweight is significantly higher in at-risk and normal pregnancies with polyhydramnios than those with normal pregnancies and normal fluid (p<0.0001). Birthweight is significantly lower in at-risk pregnancies with oligohydramnios (p<0.0001). There were no significant differences in need for amnioinfusion in labor, variables or lates influencing delivery, meconium staining, or umbilical artery pH <7.1.

Conclusion

Our study attempted to further define risk of adverse pregnancy outcomes by defining the pregnancy as normal or at-risk and amniotic fluid volumes. Contrary to our hypothesis, we did not find an increased risk of many of the adverse perinatal outcomes we studied amongst at-risk pregnancies with abnormal fluid. There was an increased risk of NICU admission associated with polyhydramnios in normal and at-risk pregnancies.

Reference ranges for the fetal mitral, tricuspid, and interventricular septum annular plane systolic excursions (mitral annular plane systolic excursion, tricuspid annular plane systolic excursion, and septum annular plane systolic excursion) between 20 and 36 + 6 weeks of gestation

Objectives This study aimed to establish reference ranges for fetal mitral, tricuspid, and interventricular septum annular plane systolic excursions (MAPSE, TAPSE, and SAPSE) in normal pregnant women between 20 and 36 + 6 weeks of gestation. Methods This prospective and cross-sectional study included 360 low-risk singleton pregnancies between 20 and 36 + 6 weeks of gestation. MAPSE, TAPSE, and SAPSE were measured by M-mode in real time in an apical or basal four-chamber view through placing the cursor at the atrioventricular junction, marked by the valve rings at the tricuspid, mitral, and basal septum, respectively. A regression analysis was done to determine the appropriate polynomial equation model for both measurements and standard deviation (SD) values in relation to gestational age (GA). The intra- and inter-observer reproducibility was evaluated using the concordance correlation coefficient (CCC) and limits of agreement (LoA). Results There was a significant positive correlation between MAPSE (r=0.705, p<0.0001), TAPSE (r=0.804, p<0.0001), and SAPSE (r=0.690, p<0.0001) and GA. The mean of each parameter ranged as follows: 2.87-5.56 mm, MAPSE; 3.98-8.07 mm, TAPSE; and 2.34-4.21 mm, SAPSE. Poor/moderate intra- and inter-observer reliability (CCC between 0.70 and 0.90) and poor/moderate agreement of all the tested parameters were evaluated (LoA between 10 and 50%). Conclusions Reference values were established for the fetal MAPSE, TAPSE, and SAPSE between 20 and 36 + 6 weeks of gestation in low-risk pregnant women. These parameters showed poor/moderate reproducibility.

Fetal acute cerebral vasoreactivity to maternal hyperoxia in low-risk pregnancies: a cross-sectional study

OBJECTIVE

To establish whether fetal cerebral vasoreactivity (CVR_O2 ), following maternal hyperoxia, is predicted by fetal cerebral and uteroplacental Doppler pulsatility indices (PI) at baseline, fetal pulmonary vasoreactivity to oxygen (PVR_O2 ), gestational age (GA), or sex.

METHODS

Pulsatility index of middle (MCA), anterior (ACA), posterior cerebral (PCA), umbilical (UA), uterine (UtA), and branch of the pulmonary arteries (PA) were obtained, by ultrasound, before (baseline), during (hyperoxia) and after 15 minutes of maternal administration of 8 L/min of 100% oxygen, through a non-rebreathing face mask, in normal singleton pregnancies within 20 to 38 weeks' gestation. CVR_O2 was defined as changes greater than zero in z score of PI of the cerebral arteries from baseline to hyperoxia. Logistic modeling was applied to identify CVR_O2 predictors.

RESULTS

A total of 97 pregnancies were eligible. In the overall population, median z scores of PI of MCA, ACA, and PCA did not differ between study phases. Based on the logistic model, baseline z scores for cerebral PI and GA were the best predictors of CVR_O2 .

CONCLUSIONS

In low-risk pregnancies, fetal CVR_O2 to hyperoxia does not occur uniformly but depends on cerebral PI and GA at baseline. These findings may provide useful reference points when oxygen is administered in high-risk pregnancies.

Impact of type I and type II maternal diabetes mellitus on fetal cardiac function assessment parameters using spectral and tissue Doppler

The aim of this study was to evaluate the impact of pregestational diabetes mellitus (DM) on fetal cardiac function two-dimensional parameters using spectral and tissue Doppler. Pregnant women between 20 and 36 + 6 weeks gestation were divided into three groups: controls, type I DM, and type II DM. The right ventricle (RV) and left ventricle (LV) annular velocity peaks were measured using spectral (E, A) and tissue (E', A', S') Doppler. The myocardial performance index was calculated as (isovolumetric contraction time [ICT] + isovolumetric relaxation time [IRT])/ejection time using tissue (MPI') and the spectral Doppler (MPI). A general linear model, with fetal heart rate as a covariant, was used to evaluate the effect of DM on the fetal heart function assessment parameters. To assess the association of type I and II DM with adverse perinatal outcomes, Fisher's exact test was used. A receiver operating characteristic curve was used to determine the best cutoff for fetal cardiac function assessment parameters to identify the neonatal composite outcomes. The sample comprised 179 pregnant women. DM had significant effect on RV and LV A peak velocities (p = 0.026 and p = 0.011, respectively). LV ICT (p < 0.001) and LV MPI (p < 0.001) were significantly affected by maternal DM. Fetuses from pregnant women with type II DM showed significantly higher LV MPI (0.492 vs. 0.459, p = 0.006) and RV S' (7.2 vs. 6.44 cm/s, p = 0.024) than controls. Fetuses from type I DM pregnant women showed increase in cardiac parameters that evaluated the LV and RV diastolic function (LV IRT' p < 0.001 and RV MPI' p = 0.044). Type I and II DM were associated with adverse perinatal outcomes: neonatal intensive care unit stay (p < 0.0001), macrosomia (p < 0.0001), hyperbilirubinemia (p < 0.0001), and hypoglycemia (p < 0.0001). The LV MPI' showed significant but moderate sensitivity in identifying the composite neonatal outcomes (AUC: 0.709, 95% CI 0.629-0.780, p < 0.001). Tissue Doppler and MPI parameters can be useful to detect subclinical cardiac dysfunction in the fetal heart of pregestational DM pregnant women.

Spotlight on the fetus: how physical activity during pregnancy influences fetal health: a narrative review

Before and during pregnancy, women often aim to improve their lifestyle so as to provide a healthier environment for their developing child. It remains unresolved, however, as to whether physical activity (PA) during pregnancy poses a possible risk or whether it might even have beneficial effects on the developing child. There is increasing evidence that PA during pregnancy is indeed beneficial to maternal physiological and psychological health and that it is generally not detrimental to the fetal cardiovascular system and neuronal function in the developing child. This also led to international recommendations for PAs during pregnancy. In the current review, we aimed to comprehensively assess the evidence of beneficial and harmful effects of maternal PA, including high-performance sports, on fetal development. The different mental and body-based relaxation techniques presented here are frequently performed during pregnancy. We found a considerable number of studies addressing these issues. In general, neither low key, moderate maternal PA nor relaxation techniques were observed to have a harmful effect on the developing child. However, we identified some forms of PA which could have at least a transient unfavourable effect. Notably, the literature currently available does not provide enough evidence to enable us to make a general conclusive statement on this subject. This is due to the lack of longitudinal studies on the metabolic and cognitive effects of regular PA during pregnancy and the wide diversity of methods used. In particular, the kind of PA investigated in each study differed from study to study.

Determination of reference values for third trimester amniotic fluid index: a retrospective analysis of a large cohort of pregnancies with comparison to previous nomograms

Purpose: To establish a new set of reference values for third-trimester amniotic fluid index (AFI) and compare them to other previously published normograms.Methods: A retrospective cross-sectional cohort analysis of all singleton sonographic evaluations >22 gestational weeks in one university affiliated medical center between 2013 and 2017. Pregnancies complicated by rupture of membranes, major anomalies/chromosomal abnormalities were excluded. One evaluation per patient per pregnancy was randomly selected. Reference values were constructed using a best-fit regression model for estimation of mean and standard deviation at each gestational age after normalization of variables and compared with previously published norms.Results: A total of 7037 ultrasound evaluations entered the analysis. Correlation between AFI and gestational age was best represented by a first-degree polynomial equation. AFI decreased gradually from 16.4 at 22 weeks to 13.3 at 40 weeks (cm, median). The standard deviation increased with gestational age with AFI ranging from 12.9-20.2 at 22 weeks and 4.7-26.2 at 40 weeks (cm, 2.5-97.5 percentile). Compared to other curves, our reference values demonstrated a higher median AFI throughout all gestation.Conclusions: Reference values for the third trimester AFI were established. Curves should be correlated with perinatal outcome prior to wide clinical implementation.

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.

[Postnatal outcome from polyhydramnios without sonographic abnormalities]

OBJECTIVES

To assess adverse outcome of polyhydramnios without morphological abnormalities and to determine the factors associated with an adverse outcome.

METHODS

This is a retrospective observational cohort study conducted in a French tertiary care unit between 2008 and 2018 including all women with singleton pregnancy complicated by polyhydramnios. Presence of morphological abnormality was an exclusion criteria. The primary outcome was the rate of adverse outcome, defined by a composite criterion including death or postnatal discovery of malformation or chronic pathology. Maternal, obstetrical, paediatric and polyhydramnios characteristics were collected.

RESULTS

Ninety-one women with polyhydramnios were included. The rate of adverse outcome was 24.2% (22/91). This rate was 20,3% in case of idiopathic polyhydramnios and 33,3% in case of maternal diabetes associated. The postnatal mortality rate was 5.5%. The rate of malformations not diagnosed in antenatal was 11%. Obesity (50% vs. 18,8%; P=0,004), early diagnosis (72,7% before 32 WG vs. 44,9%; P=0,02), and severity of polyhydramnios (22,7% vs. 4,3% in severe polyhydramnios; P=0,01) were associated significantly with an adverse outcome. In these cases, the incidence of preterm delivery was higher.

CONCLUSION

Polyhydramnios must have second-line ultrasound, including isolated maternal diabetes. A systematic genetic assessment can be discussed.

The association between polyhydramnios and CMV infection - retrospective cohort study

Objective: Polyhydramnios was suggested to be associated with CMV infection, resulting in polyhydramnios being common indication for CMV testing. However, the literature does not provide a robust evidence to support this management. We aimed to examine the association between congenital CMV infection and polyhydramnios.Methods: A retrospective cohort study was conducted. The rate of polyhydramnios was analyzed in 63 neonates/fetuses with CMV between 2013 and 2017 and compared to 351 neonates without CMV using PCR targeted to the viral DNA. The rate of oligohydramnios and small for gestational age was also evaluated.Results: All cases of polyhydramnios were of isolated polyhydramnios without malformations. The rate of polyhydramnios was six (9.5%) and 23 (6.6%) pregnancies with and without congenital CMV, respectively (p = .42). Persistent polyhydramnios (more than one documented event) was evident in one (1.6%) and 13 (3.7%) pregnancies in the positive and negative CMV groups, respectively (p = .36). The rate of congenital CMV was similar with and without oligohydramnios (6, 9.5% versus 17, 4.8%, respectively; p = .14) and with or without small for gestational age neonate (7, 11% versus 63, 18%, respectively; p = .18).Conclusion: The results of this study do not support an association between CMV infection and polyhydramnios. The need for CMV testing in isolated polyhydramnios should be reevaluated.

Outcome of fetuses with lower urinary tract obstruction and normal amniotic fluid volume in second trimester of pregnancy

OBJECTIVE

Congenital lower urinary tract obstruction (LUTO) is a rare condition with high perinatal mortality and morbidity when associated with severe oligohydramnios or anhydramnios in the second trimester of pregnancy. Severe pulmonary hypoplasia and end-stage renal disease are the underlying causes of poor neonatal outcome in these cases. However, little is known about the subset of fetal LUTO that is associated with a normal volume of amniotic fluid at midgestation. The objective of the current study was to describe the natural history, underlying causes, survival and postnatal renal function outcomes in pregnancies with fetal LUTO and normal amniotic fluid volume during the second trimester of pregnancy.

METHODS

This was a retrospective study of all pregnancies with fetal LUTO and normal amniotic fluid volume in the second trimester that received prenatal and postnatal care at our quaternary care institution between 2013 and 2017. Data on demographic characteristics, fetal interventions, perinatal survival, need for neonatal respiratory support, postnatal renal function and need for dialysis at the age of 1 and 24 months were analyzed.

RESULTS

Of the 18 fetuses that met the study criteria, 17 (94.4%) survived the perinatal period. Eleven (61.1%) pregnancies developed oligohydramnios in the third trimester, six of which were eligible for and underwent fetal intervention with vesicoamniotic shunt placement, which was performed successfully in all six cases. Two (11.1%) neonates required respiratory support owing to pulmonary hypoplasia. At the age of 2 years, 14 children had follow-up information available, two (14.3%) of whom had normal renal function, eight (57.1%) had developed some degree of chronic kidney disease (Stage 1-4) and four (28.6%) had developed end-stage renal disease (ESRD), including two who had already manifested ESRD in the neonatal period.

CONCLUSIONS

Most fetuses diagnosed prenatally with LUTO that is associated with a normal volume of amniotic fluid at midgestation will have a favorable outcome in terms of perinatal survival and few will need long-term respiratory support. However, these children are still at increased risk for chronic renal disease, ESRD and need for renal replacement therapy. Larger multicenter studies are needed to characterize the prenatal factors associated with postnatal renal function, and to investigate the role of fetal intervention in the group of fetuses that present with late-onset oligohydramnios and evidence of preserved fetal renal function. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

No. 197a-Fetal Health Surveillance: Antepartum Consensus Guideline

OBJECTIVE

This guideline provides new recommendations pertaining to the application and documentation of fetal surveillance in the antepartum period that will decrease the incidence of birth asphyxia while maintaining the lowest possible rate of obstetrical intervention. Pregnancies with and without risk factors for adverse perinatal outcomes are considered. This guideline presents an alternative classification system for antenatal fetal non-stress testing to what has been used previously. This guideline is intended for use by all health professionals who provide antepartum care in Canada.

OPTIONS

Consideration has been given to all methods of fetal surveillance currently available in Canada.

OUTCOMES

Short- and long-term outcomes that may indicate the presence of birth asphyxia were considered. The associated rates of operative and other labour interventions were also considered.

EVIDENCE

A comprehensive review of randomized controlled trials published between January 1996 and March 2007 was undertaken, and MEDLINE and the Cochrane Database were used to search the literature for all new studies on fetal surveillance antepartum. The level of evidence has been determined using the criteria and classifications of the Canadian Task Force on Preventive Health Care (Table 1).

SPONSOR

This consensus guideline was jointly developed by the Society of Obstetricians and Gynaecologists of Canada and the British Columbia Perinatal Health Program (formerly the British Columbia Reproductive Care Program or BCRCP) and was partly supported by an unrestricted educational grant from the British Columbia Perinatal Health Program. RECOMMENDATION 1: FETAL MOVEMENT COUNTING: RECOMMENDATION 2: NON-STRESS TEST: RECOMMENDATION 3: CONTRACTION STRESS TEST: RECOMMENDATION 4: BIOPHYSICAL PROFILE: RECOMMENDATION 5: UTERINE ARTERY DOPPLER: RECOMMENDATION 6: UMBILICAL ARTERY DOPPLER.

Compound Heterozygosity for Novel Truncating Variants in the LMOD3 Gene as the Cause of Polyhydramnios in Two Successive Fetuses

Polyhydramnios is sometimes associated with genetic defects. However, establishing an accurate diagnosis and pinpointing the precise genetic cause of polyhydramnios in any given case represents a major challenge because it is known to occur in association with over 200 different conditions. Whole exome sequencing (WES) is now a routine part of the clinical workup, particularly with diseases characterized by atypical manifestations and significant genetic heterogeneity. Here we describe the identification, by means of WES, of novel compound heterozygous truncating variants in the LMOD3 gene [i.e., c.1412delA (p.Lys471Serfs*18) and c.1283dupC (p.Gly429Trpfs*35)] in a Chinese family with two successive fetuses affected with polyhydramnios, thereby potentiating the prenatal diagnosis of nemaline myopathy (NM) in the proband. LMOD3 encodes leiomodin-3, which is localized to the pointed ends of thin filaments and acts as a catalyst of actin nucleation in skeletal and cardiac muscle. This is the first study to describe the prenatal and postnatal manifestations of LMOD3-related NM in the Chinese population. Of all the currently reported NM-causing LMOD3 nonsense and frameshifting variants, c.1412delA generates the shortest truncation at the C-terminal end of the protein, underscoring the critical role of the WH2 domain in LMOD3 structure and function. Survey of the prenatal phenotypes of all known LMOD3-related severe NM cases served to identify fetal edema as a novel presenting feature that may provide an early clue to facilitate prenatal diagnosis of the disease.