Is Obesity a Risk Factor for Disorders of Amniotic Fluid?

OBJECTIVES: Prior studies show conflicting evidence as to whether obesity in the absence of other medical or pregnancy-related conditions contributes to amniotic fluid disorders. The purpose of this study is to determine the association between late-pregnancy obesity with oligohydramnios (amniotic fluid index [AFI] ≤5 cm or maximum vertical pocket [MVP] <2 cm) and/or polyhydramnios (AFI ≥24 cm or MVP ≥8 cm). METHODS: This is a retrospective cohort study of 961 women with singleton gestations who had one or more obstetrical ultrasounds at a single institution at 36 0/7 weeks gestation or beyond between August 1, 2015, and May 1, 2020. Patients were included if they had valid pregnancy dating and a documented AFI and/or MVP. Patients were categorized based on body mass index or BMI (eg, normal, overweight, Class I Obesity, Class II Obesity, or Class III Obesity). RESULTS: A total of 6.2% of patients met criteria for oligohydramnios based on AFI, MVP or both (n = 60). There was no significant association between oligohydramnios and increasing BMI, regardless of obesity class (P = .21). In terms of polyhydramnios, 5.6% of patients met criteria based on AFI, MVP, or both (n = 54). Similarly, there was also no significant association between polyhydramnios and increasing BMI, regardless of obesity class (P = .66). CONCLUSIONS: Elevated maternal BMI was not significantly associated with disorders of amniotic fluid, regardless of the severity of obesity.

Pioneering a chick embryo model to explore the intrauterine etiology of developmental dysplasia of the hip in oligohydramnios conditions.

OBJECTIVE: To explore the impact of oligohydramnios on fetal movement and hip development, given its association with developmental dysplasia of the hip (DDH) but unclear mechanisms. METHODS: Chick embryos were divided into four groups based on the severity of oligohydramnios induced by amniotic fluid aspiration (control, 0.2 mL, 0.4 mL, 0.6 mL). Fetal movement was assessed by detection of movement and quantification of residual amniotic fluid volume. Hip joint development was assessed by gross anatomic analysis, micro-computed tomography (micro-CT) for cartilage assessment, and histologic observation at multiple time points. In addition, a subset of embryos from the 0.4 mL aspirated group underwent saline reinfusion and subsequent evaluation. RESULTS: Increasing volumes of aspirated amniotic fluid resulted in worsening of fetal movement restrictions (e.g., 0.4 mL aspirated and control group at E10: frequency difference -7.765 [95% CI: -9.125, -6.404]; amplitude difference -0.343 [95% CI: -0.588, -0.097]). The 0.4 mL aspirated group had significantly smaller hip measurements compared to controls, with reduced acetabular length (-0.418 [95% CI: -0.575, -0.261]) and width (-0.304 [95% CI: -0.491, -0.117]) at day E14.5. Histological analysis revealed a smaller femoral head (1.084 ± 0.264 cm) and shallower acetabulum (0.380 ± 0.106 cm) in the 0.4 mL group. Micro-CT showed cartilage matrix degeneration (13.6% [95% CI: 0.6%, 26.7%], P = 0.043 on E14.5). Saline reinfusion resulted in significant improvements in the femoral head to greater trochanter (0.578 [95% CI: 0.323, 0.833], P = 0.001). CONCLUSIONS: Oligohydramnios can cause DDH by restricting fetal movement and disrupting hip morphogenesis in a time-dependent manner. Timely reversal of oligohydramnios during the fetal period may prevent DDH.

Neonatal Outcomes Are Similar between Patients with Resolved and Those with Persistent Oligohydramnios.

OBJECTIVE: Oligohydramnios (defined as amniotic fluid volume < 5 cm or deepest vertical pocket < 2 cm) is regarded as an ominous finding on prenatal ultrasound. Amniotic fluid, however, is not static, and to date, there have been no studies comparing perinatal outcomes in patients who are diagnosed with oligohydramnios that resolves and those who have persistent oligohydramnios. STUDY DESIGN: This is a secondary analysis of a National Institutes of Health-funded retrospective cohort study of singleton gestations delivered at a tertiary care hospital between 2002 and 2013 with mild hypertensive disorders and/or fetal growth restriction (FGR). Maternal characteristics, delivery, and neonatal information were abstracted by trained research nurses. Patients with a diagnosis of oligohydramnios were identified, and those with resolved versus persistent oligohydramnios at the time of delivery were compared. The primary outcome was a composite of neonatal resuscitation at delivery: administration of oxygen, bag-mask ventilation, continuous positive airway pressure, intubation, chest compression, or cardiac medication administration. Secondary outcomes included FGR, timing, and mode of delivery. RESULTS: Of 527 women meeting study criteria, 42 had oligohydramnios that resolved prior to delivery, whereas 485 had persistent oligohydramnios. There were no significant differences in patient demographics between groups. The gestational age at diagnosis was significantly lower for patients with resolved versus persistent oligohydramnios (median: 33.0 [interquartile range, IQR: 29.1-35.9] vs. 38.0 [IQR: 36.4-39.3], p < 0.001). There was not a substantial difference in rate of neonatal resuscitation (41 vs. 32%, p = 0.31). Patients with resolved oligohydramnios were more likely to have developed FGR than those with persistent oligohydramnios (55 vs. 36%, p < 0.02). There were no significant differences for gestational age at delivery, birth weight, or neonatal intensive care unit admission. CONCLUSION: Patients whose oligohydramnios resolved were diagnosed earlier yet had similar rates of neonatal resuscitation but higher rates of FGR than those who had persistent oligohydramnios. KEY POINTS: · When diagnosed earlier in pregnancy, oligohydramnios was more likely to resolve prenatally.. · Patients who were diagnosed with oligohydramnios earlier in pregnancy had higher rates of FGR.. · There were no differences in the rates of the composite outcome of need for neonatal resuscitation when comparing those with resolved versus those with persistent oligohydramnios. No differences in composite neonatal morbidity were noted between those with resolved versus persistent oligohydramnios..

The Effect of Maternal Lower Limb Compression on Amniotic Fluid Index, Uteroplacental Perfusion, and Fetal Blood Flow in Isolated Oligohydramnios.

INTRODUCTION: The aim of this study was to examine the efficacy of pneumatic compression of the maternal lower extremities in increasing the amniotic fluid index (AFI) in pregnancies complicated by isolated oligohydramnios. METHODS: Women with isolated oligohydramnios (AFI <5 cm) at 32-41 weeks of pregnancy were connected to a sequential compression device for 60 min. Prior and after the application, AFI and the pulsatility index (PI) of a number of arteries were measured. RESULTS: The median (interquartile range) maternal age of the 21 women included was 29 years (26.50-32.00), the median parity was 1 (1-2), and the median gestational age at intervention was 37.60 weeks (37.00-39.40). The median AFI increased after the application from 4.00 (3.62-4.50) to 6.08 cm (4.90-7.03) (p < 0.001). The median PI of the fetal renal artery decreased from 2.30 (2.01-2.88) to 2.26 (1.68-2.71) (p = 0.01). The hourly fetal urine production did not increase. Changes were not significant in the PI of the umbilical artery, the middle cerebral artery, and the bilateral uterine arteries. CONCLUSION: Short-term activation of pneumatic compression on maternal lower extremities could increase the AFI in women with isolated oligohydramnios.

Prenatal diagnosis and treatment for fetal angiotensin converting enzyme deficiency.

OBJECTIVE: To elucidate an etiology in a case with persistent oligohydramnios by prenatal diagnosis and actively treat the case to achieve good prognosis. METHODS: We performed whole exome sequencing (WES) of DNA from the fetus and parents. Serial amnioinfusions were conducted until birth. Pressors were required to maintain normal blood pressure. The infant angiotensin-converting enzyme (ACE) activity, angiotensin II (Ang II, a downstream product of ACE), and compensatory enzymes (CEs) activities were measured. Compensatory enzyme activities in plasma from age-matched healthy controls were also detected. RESULTS: We identified a fetus with a severe ACE mutation prenatally. The infant was born prematurely without pulmonary dysplasia. Hypotension and anuria resolved spontaneously. He had almost no ACE activity, but his Ang II level and CE activity exceeded the upper limit of the normal range and the upper limit of the 95% confidence interval of controls, respectively. His renal function also largely recovered. CONCLUSION: Fetuses with ACE mutations can be diagnosed prenatally through WES. Serial amnioinfusion permits the continuation of pregnancy in fetal ACE deficiency. Compensatory enzymes for defective ACE appeared postnatally. Renal function may be spared by preterm delivery; furthermore, for postnatal vasopressor therapy to begin, improving renal perfusion pressure before nephrogenesis has been completed.

Prenatal diagnosis of autosomal recessive renal tubular dysgenesis caused by variants in the ACE gene: Two fetuses with anhydramnios.

INTRODUCTION: Autosomal recessive renal tubular dysgenesis (ARRTD) is a rare genetic disorder with a very high mortality rate. The typical symptoms of the disease during pregnancy are oligohydramnios, anhydramnios, and nearly all affected fetuses die after birth or have a stillbirth in late gestation, which can adversely increase maternal risks. METHODS: Oligohydramnios/anhydramnios can make both amniocentesis for diagnostic testing and morphological evaluation via ultrasound more difficult. In cases of oligohydramnios/anhydramnios suspicious for urinary tract anomalies, amnioinfusion is a meaningful technique that facilitates sampling of amniotic fluid for genetic diagnosis. RESULTS: We report two cases of fetuses with anhydramnios and invisible urinary bladder. Clinical exome sequencing from amniotic fluid revealed a biparentally inherited homozygous pathogenic nonsense ACE variant c.2503G 〉 T [p.Glu853Ter] in proband 1 and a biparentally inherited homozygous pathogenic nonsense ACE variant c.2992C 〉 T [p.Gln998Ter] in proband 2. The prognosis was poor and the patients elected to terminate the pregnancies. Additional post-mortem histopathological examination from the renal tissue of the second fetus showed renal tubular hypoplasia. CONCLUSION: To our knowledge for the first time, we describe the prenatal diagnosis of ARRTD in Vietnam, and highlight the benefit of detecting ACE variants associated with ARRTD in fetuses with oligohydramnios/anhydramnios through amnioinfusion and amniocentesis, which improves genotype-phenotype correlations and provides valuable information for reproductive counseling.

Outcomes of fetal lower urinary tract obstruction based on timing of oligohydramnios onset.

OBJECTIVE: Fetal Lower Urinary Tract Obstruction (LUTO) is associated with oligohydramnios and significant fetal morbidity, resulting in poor lung development and perinatal death. However, oligohydramnios may develop at different gestational periods, and the impact of timing on fetal outcomes remains unknown. Our objective was to characterize the impact onset of oligohydramnios had on prenatal outcomes. METHODS: This study is a retrospective cohort study of all patients with a prenatal diagnosis of LUTO at our tertiary referral center from 2014 to 2023. All patients underwent detailed ultrasonography and interdisciplinary counseling and were subsequently delivered at our institution. Data were obtained from electronic medical records and complete extraction was required for final inclusion. RESULTS: During the study time period, 93 patients met inclusion criteria of which 68 (73.1%) developed oligohydramnios during their pregnancy. 63 (93%) of these pregnancies resulted in livebirths with 28 (41.1%) perinatal deaths. Onset of oligohydramnios was earlier in pregnancies with perinatal death (23 vs. 28 weeks, p = 0.004) and associated with pulmonary hypoplasia. CONCLUSIONS: Our data show the impact of oligohydramnios timing in pregnancy on pulmonary hypoplasia and ultimately perinatal death. This allows for detailed patient counseling on the impact oligohydramnios may have on pregnancies by the gestational age of onset.

Use of non-steroidal anti-inflammatory drugs in pregnancy and oligohydramnios: a review.

OBJECTIVE: The aim of this review is to evaluate the relationship between the use of non-steroidal anti-inflammatory drugs (NSAIDs) during last trimesters of the pregnancy and the reduction of amniotic fluid. METHODS: Electronic databases were searched (PubMed, Medline, and Scopus). Selection criteria included studies reporting the relationship between oligohydramnios and use of NSAID during pregnancy. We analyzed the median age of women, weeks of pregnancy at the beginning of the drug administration, kind of medication, period of exposure and dosage, deepest vertical pocket (DVP), and amniotic fluid index (AFI). RESULTS: Of the 68 records identified, we analyzed 29 studies investigating the administration of NSAIDs, including 11 studies examined the administration of the Indomethacin, four articles have focused on the use of Nimesulide, and only two manuscripts considered the use of Diclofenac. We found a strict correlation between the development of oligohydramnios and the use of NSAIDs. The oligohydramnios is reversible, and the normal amount of amniotic fluid is restored after the interruption of the treatment. CONCLUSIONS: The use of NSAIDs should be considered when maternal benefits outweigh the potential fetal risk, at the lowest effective dose for shortest duration. Beyond 48 h of NSAIDs treatment, we consider ultrasound monitoring of amniotic fluid, and we suggest stopping therapy if a decline AFI is present.

Small estimated placental volume (EPV) in the setting of decreased fetal movement.

Although 60.5 % of clinically unexplained stillbirths can be attributed to placental insufficiency and/or fetal growth restriction, clinicians rarely calculate estimated placental volume (EPV). We present a scenario in which EPV was used to inform patient care of a 28-year-old with decreased fetal movement at 32 weeks and 1 day gestation. Although estimated fetal weight (EFW), amniotic fluid index (AFI), and nonstress test (NST) were normal, EPV was low (<0.1st percentile), which prompted more frequent patient follow-up. Oligohydramnios was detected at 38 weeks and 1 day, and labor was induced. An infant with birthweight in the 12th percentile for gestational age was born. We learned that EPV can precede intrauterine growth restriction (IUGR), oligohydramnios, and low birthweight.

Congenital lower urinary tract obstruction with spontaneous fetal bladder rupture due to posterior urethral valves: a case report.

BACKGROUND: Congenital lower urinary tract obstruction (LUTO) is a rare but significant condition affecting fetal urinary tract development. LUTO has a range of etiologies, with posterior urethral valves (PUV) being the most common cause. The prenatal diagnosis of LUTO plays a crucial role in recognizing the condition and guiding management decisions. Prenatal ultrasound serves as the primary tool for identifying LUTO, with key findings including megacystis, bladder wall thickening, oligohydramnios, hydronephrosis, and the 'keyhole sign' indicating dilatation of the posterior urethra. We present a case of congenital LUTO with a rare complication of spontaneous fetal bladder rupture and urinary ascites, treated by peritoneo-amniotic shunt placement. CASE PRESENTATION: A 27-year-old pregnant Caucasian women was referred at 28 weeks of pregnancy due to the presence of megacystis and bilateral hydronephrosis on routine ultrasound and suspicion of LUTO. Repeat ultrasound at 29 weeks showed significant fetal ascites, oligohydramnios and resolution of megacystis and hydronephrosis, after which diagnosis of spontaneous bladder rupture was made. Despite ascites aspiration and amnio-infusion, there was persistent ascites and oligohydramnios. A peritoneo-amniotic shunt was placed with resolution of ascites and normalization of the amniotic fluid volume. At 35 weeks, relapse of the megacystis was observed with bilateral pyelectasis and oligohydramnios, possibly due to healing of the bladder rupture, after which elective cesarean section was planned. Cystography confirmed spontaneous healing of the bladder rupture and the presence of posterior urethral valves, which were resected in the neonatal period with cold knife incision. Total follow-up of 8 years continued to show positive ultrasonographic results and good renal function, but the child suffers from bladder dysfunction, manifesting as overactive bladder disease. CONCLUSIONS: LUTO might lead to important renal dysfunction and pulmonary hypoplasia in case of increasing disease severity. Spontaneous bladder rupture might improve renal prognosis, acting as a pop-off mechanism by decompression of the urinary tract. However, fetal bladder rupture is rare and only few cases have been reported. Prenatal intervention can be considered for moderate or severe LUTO, but the benefit for long-term outcome remains uncertain and further studies are needed.

Admission ultrasonography as a means of identifying unrecognized fetal compromise in term singleton pregnancies at the onset of labor - a feasibility study.

OBJECTIVES: Apparently uncomplicated low-risk pregnancies, especially first time births, account for a significant proportion of adverse birth outcomes. Improved risk stratification with a simple bedside scan on admission in early labor could potentially reduce adverse intrapartum outcomes. The aim of this feasibility study was to assess a cohort of low-risk subjects with admission ultrasonography at the onset of labor with a view to conducting a future randomized controlled trial (RCT). The objectives were three-fold; i) to determine the logistics of performing a labor admission ultrasound scan ii) to establish whether abnormal ultrasound features can be identified and iii) whether they are associated with emergency delivery and/or poor condition of the neonate at birth. METHODS: We performed a prospective cohort study of 295 participants with term singleton cephalic pregnancies admitted in early labor or for labor induction with non-fetal indications. The setting was a university teaching hospital in Ireland with almost 8000 births annually. A bedside ultrasound scan was performed to assess fetal biometry, amniotic fluid volume and placental maturity. Patients and their babies were followed up until hospital discharge. The outcomes of interest included image quality, time to perform a scan, oligohydramnios (Single Deepest Pool ≤ 2 cm), small for gestational age (SGA; abdominal circumference <10th centile), mature placenta (Grannum 2 or 3), pathological CTG, emergency cesarean section (CS), fetal acidosis (cord arterial pH <7.10 or base excess <-12.0), low Apgar score <7 at 5 min and neonatal unit admission. RESULTS: Image quality was optimal in 274 of the 295 scans (93%) and 271 (92%) were completed in less than 10 min. Of this low-risk population, 67 of 294 (23%) had oligohydramnios, 11 (4%) were small for gestational age and 87 (30%) had a mature placenta (Grannum grade 2). The incidence of pathological CTG and emergency CS was higher among patients with oligohydramnios than those with a normal scan but did not reach statistical significance; Odds Ratio 3.40 (95% Confidence Intervals 0.55 to 20.92) and OR 1.43 (95% CI 0.66 to 3.08) respectively. The mean birthweight was significantly lower in those with oligohydramnios -139 g (95% CI -248 to -30) and admission scan detected SGA -357 g (95% CI -557 to -137). Adverse perinatal outcomes were uncommon with a higher incidence of fetal acidosis (pH < 7.10) in the oligohydramnios group. The incidence of neonatal unit admission >24 h was higher in the oligohydramnios group but not statistically significant; OR 3.75 (95% CI 0.61 to 22.97). Results for SGA alone were non-significant and results for oligohydramnios and SGA combined were similar to those for oligohydramnios alone. CONCLUSIONS: Admission ultrasonography is feasible in a routine clinical setting, but evidence of benefit is weak and does not currently justify a randomized controlled trial.

Assessment of Amniotic Fluid Volume in Pregnancy.

Amniotic fluid (AF) is an integral part of the fetal environment and is essential for fetal growth and development. Pathways of AF recirculation include the fetal lungs, swallowing, absorption through the fetal gastrointestinal tract, excretion through fetal urine production, and movement. In addition to being a marker for fetal health, adequate AF is necessary for fetal lung development, growth, and movement. The role of diagnostic imaging is to provide a detailed fetal survey, placental evaluation, and clinical correlation with maternal conditions to help identify causes of AF abnormalities and thereby enable specific therapy. Oligohydramnios prompts evaluation for fetal growth restriction as well as genitourinary issues, including renal agenesis, multicystic dysplastic kidneys, ureteropelvic junction obstruction, and bladder outlet obstruction. Premature preterm rupture of membranes should also be clinically excluded as a cause of oligohydramnios. Clinical trials evaluating amnioinfusion are underway as a potential intervention for renal causes of oligohydramnios. Most cases of polyhydramnios are idiopathic, with maternal diabetes being a common cause. Polyhydramnios prompts evaluation for fetal gastrointestinal obstruction and oropharyngeal or thoracic masses, as well as neurologic or musculoskeletal anomalies. Amnioreduction is performed only for maternal indications such as symptomatic polyhydramnios causing maternal respiratory distress. Polyhydramnios with fetal growth restriction is paradoxical and can occur with maternal diabetes and hypertension. When these maternal conditions are absent, this raises concern for aneuploidy. The authors describe the pathways of AF production and circulation, US and MRI assessment of AF, disease-specific disruption of AF pathways, and an algorithmic approach to AF abnormalities. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

[Clinical phenotype and genetic analysis of a fetus with Glutaracidemia type II C].

OBJECTIVE: To explore the clinical phenotype and genetic variants of a fetus with Glutaracidemia type II C (GA II C). METHODS: Clinical data of a 32-year-old pregnant woman and her fetus with GA II C diagnosed at the Third Affiliated Hospital of Zhengzhou University in December 2021 due to the enlargement and enhanced echo of the kidneys and oligohydramnios fluid at 17 weeks were analyzed retrospectively. Amniotic fluid sample of the fetus and peripheral blood samples of the couple were collected for whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing. Copy number variation (CNV) was detected by using low-coverage whole genome sequencing (CNV-seq). RESULTS: At 18 weeks' gestation, ultrasound revealed that the fetus had enlargement and enhanced echo of the kidneys along with no echo of renal parenchymal tubular fissure and oligohydramnios. MRI at 22 weeks' gestation confirmed that both kidneys were enlarged with uniformly increased abnormal T2 signal and decreased DWI signal. The volume of both lungs was small, with slightly higher T2 signal. No CNV was detected in the fetus. WES revealed that the fetus has harbored compound heterozygous variants of the ETFDH gene, namely c.1285+1G＞A and c.343_344delTC, which were inherited from its father and mother, respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were classified as pathogenic (PVS1+PM2_Supporting+PS3_Supporting; PVS1+PM2_Supporting+PM3). CONCLUSION: The c.1285+1G＞A and c.343_344delTC compound heterozygous variants of the ETFDH gene probably underlay the disease in this fetus. Type II C glutaric acidemia may manifest as bilateral kidney enlargement with enhanced echo and oligohydramnios. Discovery of the c.343_344delTC has enriched the spectrum of ETFDH gene variants.

Oligohydramnios or Anhydramnios and Ultrasonically Normal Renal Echotexture Secondary to Autosomal Recessive Renal Tubular Dysgenesis: An Important Consideration in the Prenatal Setting.

INTRODUCTION: Autosomal recessive renal tubular dysgenesis (ARRTD) is a rare disorder of renal tubular development. ARRTD is a severe condition with high risk of fetal demise and early neonatal death, with only limited case reports of survival over 2 years [Clin Kidney J. 2012 Feb 1;5(1):56-8]. Prenatal diagnosis of ARRTD is challenging, and diagnosis has only previously been confirmed after postnatal or post-mortem investigation. CASE: To the best of our knowledge, we describe the first reported case of utilizing targeted genetic testing on the chorionic villous sample (CVS) to identify a homozygous variant in the angiotensinogen (AGT) gene. DISCUSSION: By substantiating the diagnosis of ARRTD prenatally, we allow timely and appropriate counseling during pregnancy.

Predictive factors for survival in patients with oligohydramnios secondary to antenatal kidney disease.

BACKGROUND: Renal oligohydramnios (ROH) is caused by bilateral congenital abnormalities, either of renal parenchymal or obstructive origin. ROH is a poor prognostic factor of neonatal survival; lung hypoplasia is reported to be the main cause of mortality. We aimed to describe the fetal morbidity and pre- and postnatal mortality in case of ROH due to renal congenital pathologies and to find predictive risk factors for morbidity and mortality. METHODS: All data were collected in Trousseau Hospital in the obstetric, neonatology, and pediatric nephrology units, from 2008 to 2020. RESULTS: We included 66 fetuses with renal parenchymal pathologies posterior urethral valves (PUV) (N = 25), bilateral kidney agenesis (N = 10), hypodysplasia (N = 16), and polycystic kidney disease (N = 10) causing oligohydramnios identified on antenatal ultrasound. Total pre- and postnatal mortality was 76% (50/66). Mortality, excepting termination of pregnancy (TOP), was 65%. The presence of pneumomediastinum and pneumothorax was not different in survivors and non-survivors. Fetuses with kidneys having features of hypodysplasia on ultrasound at T2 and those with oligohydramnios before 32 weeks GA had a higher risk of death. There was a significant difference in plasma creatinine of the surviving patients compared to the deceased patients, from day 3 onwards (183 µmol/L [88; 255] vs. 295 µmol/L [247; 326]; p = 0.038). CONCLUSIONS: The main differences between survivors and non-survivors among patients with "renal oligohydramnios" were oligohydramnios detection before 32 weeks GA, dysplasia detection on the second trimester ultrasound, and increase of serum creatinine from day 3 onwards. A higher resolution version of the Graphical abstract is available as Supplementary information.

Estimate of genetic variants using CNV-Seq for fetuses with oligohydramnios or polyhydramnios.

BACKGROUND: Oligohydramnios or polyhydramnios, is associated with chromosomal aberrations, particularly aneuploidy. However, its correlation with copy number variation (CNV) remains unclear. METHODS: We retrospectively analyzed 428 cases with an abnormal level of amniotic fluid, comprising of 139 cases of single ultrasound findings (SU group) and 289 cases of multiple ultrasound findings (MU group), by CNV sequencing (CNV-Seq) and followed their pregnancy outcomes. RESULTS: The overall detection rate of clinically significant findings was 8%, with 5% in the SU group and 11% in MU group. Besides, 18 microdeletion/microduplication syndromes were detected, with the highest rate of renal cysts and diabetes syndrome (22%, 4/18). Also, the rate of termination of pregnancy in MU group was much higher than that in the SU group (29% vs. 10%, ***p < 0.001), and in the MU-oligohydramnios subgroup, it was the highest (34%), regardless of cases with chromosomal anomaly and lost to follow-up. CONCLUSION: Our results showed that the abnormal level of amniotic fluid, especially combined with other ultrasound abnormalities, is closely related to chromosomal abnormalities and genetic CNVs. CNV-Seq may be useful in investigating pregnancies with an abnormal amniotic fluid level.

[Factors associated with the survival of fetuses with a prenatal diagnosis of megabladder]. / Factores asociados a sobrevida de fetos con diagnóstico prenatal de megavejiga.

The presence of fetal megacystis in a renal ultrasound may suggest a mechanical or functional bladder outlet obstruction, an uncommon condition with a poor outcome. OBJECTIVE: To determine prog nostic factors in fetuses with prenatal diagnosis of megacystis. PATIENTS AND METHOD: Retrospective study carried out between 2003 and 2018 in the Orient Perinatal Reference Center (CERPO), Uni versity of Chile. Prenatal and postnatal data were analyzed, as well as etiology, pulmonary hypoplasia, medical and surgical treatment, mortality, renal function, and need for renal replacement therapy. The primary variable analyzed was survival at one year, and the secondary ones were renal function and predictors of survival. Statistical analysis was performed using the Mann-Whitney U tests or Fisher test, and a p < 0.05 was considered statistically significant. RESULTS: Twenty-five fetuses with prenatal diagnosis of megacystis were included. 52% of them presented oligohydramnios and 84% showed renal anomalies. Vesicocentesis was performed in 15 fetuses and vesicoamniotic shunt was performed in 5 cases. There were 6 intrauterine fetal deaths (24%) and, among the 19 live births, 9 died soon after birth (36%) and 1 died in the post-neonatal period due to a non-nephron-urological cause. Nine newborns survived by one year of age (36%), seven of them with associated nephron- urological anomaly, and two were healthy patients. Two patients developed chronic kidney disease. The presence of pulmonary hypoplasia was the only factor associated with increased perinatal mor tality (p<0.05) secondary to oligohydramnios in all cases. Oligohydramnios was not identified as a prognostic factor in this study. CONCLUSIONS: The prenatal diagnosis of megacystis comprises a wide spectrum of pathologies including conditions with a high perinatal mortality rate to healthy fetuses with transient enlarged bladder without nephron-urological pathology. The only factor associated with increased perinatal mortality was pulmonary hypoplasia.

Fetal surgery for obstructive ureterocele using an ultrasound-guided needle laser ablation technique: a case series.

INTRODUCTION: Obstructive ureterocele is an intravesical cystic dilation of the distal end of the ureter associated with anhidramnios and dilation of both renal pelvises. METHODS: This is a case-series of prenatally diagnosed ureterocele. Cases were selected at a third level reference hospital in Monterrey Mexico between 2010 and 2018. Eligible patients for fetal therapy were selected when bilateral hydronephrosis and severe oligohydramnios were found before 26+0 weeks of gestation. The fetal intervention comprised an ultrasound-guided needle laser technique for ureterocele ablation. RESULTS: There were six cases of prenatal diagnosed of ureterocele, two cases showed anhidramnios at 23 weeks of gestation and were considered obstructive ureterocele. For these two cases, fetal surgery was performed using laser ablation of the ureterocele through an ultrasound-guided needle. In both, the urinary tract was decompressed, and the volume of amniotic fluid improved allowing to carry both pregnancies until term, one of them vaginally and the other by cesarean section. In the postnatal follow-up of both cases, the first neonate died due to neonatal asphyxia at 48-hours, and the second neonate required removal of the abnormal collecting system. CONCLUSIONS: The use of ultrasound-guided laser ablation for the decompression of obstructive ureterocele is a safe and feasible technique in extremely premature fetuses that could allow survival of the affected fetus until term. Patients receiving an early prenatal diagnosis of obstructive ureterocele may benefit from fetal therapy to reduce the risk of lung hypoplasia and stillbirth.Established factsPrenatal mortality of bilateral obstructive ureterocele is up to 45%.Only a few techniques have been described for the management of prenatally bilateral obstructive ureterocele; among them, the puncturing of the ureterocele which may require more than one intervention during fetal, laser by fetoscopy which may increase the risk of postoperative complications, and ultrasound-guided laser fulguration which seems to be effective and safe.Novel insightsThe present is the first description of a case series on ureteroceles comprising two ultrasound-guided laser therapy as an effective treatment for bilateral obstructive ureterocele requiring a single intervention.The use of ultrasound-guided laser in obstructive cases avoids fatality and lung hypoplasia due to severe oligohydramnios. Still, the neonatal prognosis of the affected side at two years of age remains unchanged.