ABSTRACT
Objective
The impact of prenatal diagnosis timing in posterior urethral valves is unclear. We aimed to compare renal function between patients with suspected PUV diagnosed before or after 28 weeks of gestation in a population who underwent systematic T2 and T3 ultrasounds.
Methods
We performed a retrospective analysis of a prospective cohort of patients with prenatally suspected and postnatally confirmed PUV. Patients were stratified by timing of prenatal ultrasound detection of urinary tract abnormalities (T2 vs T3). We compared nadir creatinine and mid‐term eGFR (> 5 years of follow‐up).
Results
72 boys with postnatally confirmed PUV were included. Thirty‐seven patients (51%) were diagnosed before 28 weeks' gestation (T2 group). This early group had significantly higher NC values (median 38 vs. 26 μmol/L, p < 0.05) and lower eGFR at mid‐term follow‐up (median 85 vs. 105 mL/min/1.73 m2, p < 0.05) compared to the T3 group.
Conclusions
PUV suspected during the second trimester of gestation is associated with significantly worse NC and mid‐term renal function compared with those suspected later in pregnancy (T3). Reports of prenatal diagnosis of PUV should dichotomize between T2 and T3 diagnoses. The true rate of PUV that could be diagnosed prenatally is higher than expected.
Summary
-
What's already known about this topic?
-
◦
Posterior urethral valves can be suspected prenatally. Timing of diagnosis whether prenatal versus postnatal impacts prognosis
-
◦
-
What does this study add?
-
◦
Impact of timing within the prenatal window and its impact on mid‐term (> 5 years) renal prognosis. Incidence of T2 versus T3 diagnosis in a cohort of patients with systematic T2 and T3 ultrasounds
-
◦
1. Introduction
Posterior urethral valves (PUV) are congenitally obstructing membranous folds of the male posterior urethra, affecting approximately 1 in 3800 male births per year [1, 2] and representing the most common cause of bladder outlet obstruction in boys. They cause increased intravesical pressure during fetal kidney development and are associated with congenital renal dysplasia and abnormal bladder function [3].
Despite the improvement in prenatal assessment and postnatal management, PUV still represents one of the greatest challenges for pediatric urologists and nephrologists, with a quarter of children progressing to renal failure [4, 5].
Several studies have discussed prenatal features of poor prognosis as well as differences in prognosis according to pre or postnatal presentation. However, many of these studies include patients for whom only a second trimester (T2) ultrasound (US) was performed as systematic T3 ultrasounds are not offered everywhere. In our country, all pregnancies undergo a systematic second and third trimester (T3) pregnancy US, allowing for identification of abnormalities on T3 not present on T2. The aim of this study was to determine the rate of T2 versus T3 diagnosis of PUV in a cohort with systematic T2 and T3 ultrasounds, and to compare mid‐term renal function (> 5 years) between these two groups.
The hypothesis was that those with T2 abnormalities would be associated with a worse outcome than those with a T3 diagnosis.
2. Materials and Methods
We used the existing prospective database of the “CIRCUP” trial, which included only boys with suspected prenatal and confirmed postnatal PUV.
Patients were stratified into two groups according to the prenatal presentation: presence of T2 versus T3 abnormalities, with the cutoff set at 28 weeks of pregnancy for the second trimester ultrasound.
All patients in the T3 abnormality group had, by definition, a T2 ultrasound that was considered normal, without any signs suggesting PUV.
The following prenatal variables were assessed: US gestational age, the volume of amniotic fluid, urinary tract abnormalities focusing on the aspect of renal parenchyma, presence of hydronephrosis, bladder wall thickness and dilatation, and specific US findings such as the keyhole sign [6].
Postnatally, per protocol, all patients had an abdominal ultrasound and a voiding cystogram confirming the diagnosis of PUV within the first month of life.
We collected data on early nadir creatinine (NC) (defined as lowest creatinine within the first 6 months of life) and serum creatinine values as well as weight and height at the latest follow up (at least 5 years) to assess mid‐term renal function.
Renal function was based on the eGFR values, which were calculated using the updated Bedside Schwartz Formula [36.5 x (height (cm)/serum creatinine μmol/L)] [7]. We considered that an eGFR < 90 was an initial sign of chronic kidney disease (CKD) and an eGFR below 60 a moderate kidney function decrease.
We then compared the medians of NC and mid‐term (> 5 years) eGFR between the two groups, as well as the proportion of boys with eGFR < 90 and < 60 in each group. We also looked at the urinary protein to creatinine and albumin to creatinine ratios in both groups.
We considered that a value of P/C > 20 and A/C > 3 was pathological.
Demographic characteristics were presented as median (interquartile range [IQR 1–3]) for continuous variables and counts/percentages for categorical variables. Median comparison between groups was made using the non‐parametric Mann‐Whitney U test; we used a chi‐square test for categorical data and to compare proportion of children with eGFR < 90 in each group.
The study respects our national ethics regulations.
3. Results
The CIRCUP study included 90 patients included between 2012 and 2017 [8]. 72 had complete data and were included in this analysis; 37 (51%) had signs of PUV visible on the T2 ultrasound (< 28 gestational weeks), 35 (49%) had signs visible on the T3 ultrasound. The 18 patients who were not included either had missing prenatal data or were lost to follow‐up before the age of 5. To assess the risk of selection bias, the available data of these patients were compared to the included patients and there were no differences in demographics or presentation.
All patients had a postnatal cystogram and underwent valve resection within 28 days of life, as required by the protocol in the CIRCUP trial.
The main prenatal features and baseline clinical characteristics of these patients stratified according to the term of abnormalities detection are summarized in Tables 1 and 2.
TABLE 1.
Prenatal ultrasound characteristics according to term of abnormalities presentation (n = 72).
| Variables, median (Q1‐Q3) | T2 (n = 37) | T3 (n = 35) | Stat test (p value) | |
|---|---|---|---|---|
| Gestational age at US abnormalities first detection (weeks) | 22 (22–23) | 32 (31.5–33) | MW (< 0.05) | |
| Amniotic fluid volume ‐ n (%) | Chi2 (0.49) | |||
| Normal | 26 (70) | 25 (71) | ||
| Oligo—anhydramnios | 11 (30) | 10 (29) | ||
| Keyhole sign | 9 (24%) | 9 (26%) | Chi2 (0.9) | |
| Distended thickened wall bladder | 24 (65%) | 22 (63%) | Chi2 (0.9) | |
| Hydronephrosis ‐ n (%) a , b | Chi2 (0.5) | |||
| Absent | 4 (12.5%) | 0 (0%) | ||
| Unilateral | 4 (12.5%) | 6 (18%) | ||
| Bilateral | 24 (75%) | 27(82%) | ||
Abbreviations: Chi2 = Chi‐squared test, MW = Mann‐Whitney test, US = ultrasound.
Missing data from 5 patients T2 group.
Missing data from 2 patients T3 group.
TABLE 2.
Patients' clinical characteristics (n = 72).
| Variables, median (Q1‐Q3) | T2 (n = 37) | T3 (n = 35) | Stat Test (p value) |
|---|---|---|---|
| Gestational age at birth (weeks) | 39 (38–39) | 37 (37–39) | MW (< 0.05) |
| Weight at birth (g) | 3340 (3025–3654) | 3135 (2923–3498) | MW (0.1) |
| Age at PUV resection (days) | 7 (4–40) | 5 (4–15) | MW (0.3) |
| Nadir creatinine (μmol/L) | 38 (22–57) | 26 (20.5–28) | MW (< 0.05) |
| Follow‐up (years) | 7.3 (6.4–8.6) | 7 (6–7.6) | |
| Serum creatinine (μmol/L) at the latest follow up | 56 (45–95) | 41 (34.5–51.5) | MW (< 0.05) |
| eGFR at the latest follow‐up | 85 (47–97) | 105 (91–129.5) | MW (< 0.05) |
| eGFR < 90 n (%) | 21 (57) | 8 (23) | Chi2 (< 0.05) |
| eGFR < 60 n (%) | 13 (35) | 4 (11) | Chi2 (< 0.05) |
| Urinary protein‐to‐creatinine ratio > 20 n(%) a | 9 (56) | 9 (39) | Chi2 (0.29) |
| Urinary albumin‐to‐creatinine ratio > 3 n(%) b | 10 (53) | 4 (19) | Chi2 (< 0.02) |
Abbreviations: Chi2 = Chi‐squared test, eGFR = estimated Glomerular Filtration Rate, MW = Mann‐Whitney test, PUV = posterior urethral valves.
Available data on 16 patients in the T2 group and 19 patients in the T3 group.
Available data on 23 patients in the T2 group and 21 patients in the T3 group.
Median follow‐up was 7.2 years [IQR: 6.2–8].
3.1. Prenatal Findings (Table 1)
Twenty‐one pregnancies (29%) had either oligo or anhydramnios at the latest prenatal ultrasound, 46 patients had a bladder anomaly (64%) while only 18 patients presented with the keyhole sign (25%); the overall incidence of hydronephrosis was 85% (uni or bilateral). There was no significant difference in the rate of these prenatal characteristics between the T2 and T3 groups (Chi square test).
3.2. Postnatal Outcome (Table 2)
The T2 group had significantly higher nadir creatinine, with a median value of 38 (22–57) versus 26 (20.5–28) for the T3 children (p < 0.05). There was a statistically significant difference in median mid‐term renal function, as determined by latest eGFR values, between the T2 and T3 group: respectively 85 (47–97) and 105 (91–129.5) (p < 0.05).
We also found a significant difference in the proportion of children with an eGFR < 90 in both groups, 21 (57%) for T2 versus 8 (23%) for the T3 group (Chi2; p < 0.05), as well as when considering an eGFR< 60 [ 13 (35%) T2 versus 4 (11%) T3 (Chi2; p < 0.05)]. Urinary protein‐to‐creatinine ratio was available for 16 patients in the T2 group (16/37) and 23 patients in the T3 group (23/35). Proteinuria was present in 56% of patients in the T2 group and 39% of patients in the T3 group, with no statistically significant difference between the groups (chi‐square test, p = 0.29). We examined albuminuria with albumin‐to‐creatinine ratio as well and found a statistical difference showing more albuminuria in the T2 group, as could be expected (chi‐square test, p = 0.02).
4. Discussion
There have been previous studies on the timing of PUV diagnosis and outcome. However, most of these studies have focused on the differences between prenatal and postnatal diagnosis of PUV [9, 10, 11, 12], or how the age of PUV postnatal diagnosis impacts the clinical outcome [12], but not specifically on the timing within the prenatal window. This means that, what is referred to as the “prenatal diagnosis group” is a heterogeneous population with a wide range of presentations. Timing of diagnosis, or suspected prenatal diagnosis depends not only on the presence of visible urological anomalies but also on the fact that prenatal ultrasounds were performed.
In many countries, such as the UK or Italy, only a second trimester ultrasound is routinely performed [13, 14] and, if normal, no T3 screening is then provided. In our country's healthcare system, not only are systematic T2 and T3 ultrasounds recommended but they are free and thus effectively performed in the large majority of the population. This means that all the children we diagnosed on T3 would have been diagnosed postnatally in countries without systematic T3. Some studies give numbers of “progression to renal failure” for postnatal presentation, but they do not take into account differences in prenatal screening [15]. What is called postnatal presentation is in fact failed prenatal detection in many cases because T3 ultrasound was not performed. Interestingly, in a recent review [16] on fetal lower urinary tract obstruction, there is a distinction between first and second trimester outcomes, but the population of T3 patients is not specifically addressed. There is definitely a lack of definition of T2 versus T3 patients. In the USA, it is currently recommended that if only one ultrasound is performed, it should be done at 18–20 weeks of gestation [17]. Despite advocating that a T3 ultrasound would help monitor fetal anatomy and identify anomalies that can directly affect the outcome of both the patient and the pregnancy, there is still no universal recommendation to obtain a routine ultrasound in the third trimester [18, 19].
Therefore, a major clinical implication of our findings is the value of systematic prenatal ultrasound screening at both T2 and T3, as performed in our country. Nearly half of our cohort had no signs of PUV at the T2 scan, with the diagnosis made only at the third trimester. In our center's experience over the last 15 years, the vast majority of patients diagnosed with PUV had prenatal signs. Currently, it is stated that prenatal diagnosis represents between 40% and 75% of PUV diagnoses, but this is due to the absence of systematic T3 US [9, 16, 20].
From a clinical point of view, diagnosing postnatally children who had signs which could have been diagnosed prenatally impacts the true prognosis of each of these categories.
Our results demonstrate that in a population of boys in whom systematic T2 and T3 ultrasounds were performed, boys with PUV identified before 28 weeks of pregnancy had significantly worse mid‐term renal outcome. Mid‐term renal outcome was evaluated using both nadir serum creatinine, which is well known as a predictor of renal outcome in PUV [21], and eGFR at 5 years follow up minimum, compared to those diagnosed later. An eGFR < 90 mL/min/1.73 m2 ‐ a threshold indicating chronic kidney disease (CKD)‐ was found in over half of the children in the T2 group, compared to barely a quarter in the T3 group. This confirms the difference in prognosis associated with the presence of prenatal abnormalities.
Any discussion regarding prenatal diagnosis and management of posterior urethral valves must integrate the discussion about fetal intervention [22]. However, our cohort did not include systematic fetal urine sampling as it is only offered in certain specific circumstances, meaning we could not classify our patients according to the Ruano classification for instance [23]. Furthermore, current evidence on the role of fetal intervention demonstrates improved survival but not improved renal function, meaning its use is still limited to certain expert centers or study conditions [24]. This study focused solely on long‐term renal function according to timing of prenatal diagnosis.
Furthermore, while earlier detection (T2) appears to be a marker of more severe renal disease, later prenatal detection (T3) allows for a proactive postnatal care. Indeed, patients who would have been diagnosed on T3 but are not are therefore diagnosed postnatally based on symptoms such as pyelonephritis and chronic voiding difficulties. This will worsen their condition, suggesting once more the additive value of a systematic T3 ultrasound.
Interestingly, the rate of specific prenatal ultrasound findings (hydronephrosis, bladder aspect, keyhole sign, amniotic fluid volume) did not differ significantly between the two groups. Our hypothesis is that certain prenatal characteristics, especially a decrease in the quantity of amniotic fluid, are correlated with postnatal renal function [25, 26], regardless of the timing of their onset.
Delayed diagnosis can impact early postnatal management, but also parental counseling. A study conducted in 2021 on prenatal counseling following diagnosis of congenital anomalies of the urinary tract showed that mothers were reassured by the prenatal consultation with the pediatric urologist and that the most important information they sought was management of the baby born and practical aspects [27]. Prenatal diagnosis of PUV will allow for planned follow‐up and decisions regarding the need for antibiotic prophylaxis.
Our study has several limitations. The sample size, while one of the largest available with mid‐term follow‐up in antenatally diagnosed PUV, and the retrospective analysis of prospectively collected data may carry inherent bias. Nevertheless, it is a homogeneous population, with standardized postnatal management per protocol [8]. Our median follow‐up was little over 7 years, which can be perceived as insufficient to cover the pathology spectrum of PUV and possible outcome, as stated by Yadav et al. [9] and therefore considered as mid‐rather than long‐term [28]. The statistically significant differences that we assessed in terms of NC and eGFR between T2 and T3 might become even more evident during late childhood, adolescence and adult life. Finally, though we do have data on bladder function and management, there was no difference in the number of children requiring some sort of bladder management between both groups, and sub‐group analysis taking into account all the different scenarios was not possible. A notable strength of our study lies in the systematic approach to prenatal ultrasound assessment, with imaging conducted in both second (T2) and third (T3) trimesters, even in cases where the T2 ultrasound was normal. Furthermore, this series is based on a recent cohort and the improvement of prenatal ultrasound techniques means these are probably more reliable numbers than those published almost 30 years ago [18]. We do not have the number of cases of termination in each participating center during the study period. However, as termination is only envisaged for the worse cases, the most probable hypothesis would be that there are more T2 diagnosis terminations than T3 diagnosis terminations. This would further confirm the fact that the T2 group is associated with a more severe renal prognosis.
To conclude, in our cohort, T2 diagnosis was associated with worse midterm renal function. The proportion of boys who can be diagnosed prenatally is much higher than previously reported.
The study supports the use of both second and third trimester ultrasounds for prenatal screening of urinary tract abnormalities, in order to detect boys with urethral obstruction and allow for subsequent risk stratification.
Funding
The authors have nothing to report.
Ethics Statement
This study is a retrospective analysis of the CIRCUP trial database. All parents signed a consent for inclusion in the CIRCUP trial. For this retrospective analysis, no further ethical approval was necessary according to our legislation.
Conflicts of Interest
The authors declare no conflicts of interest.
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
References
- 1. Bingham G., Leslie S. W., and Rentea R. M., “Posterior Urethral Valves,” in Statpearls, Treasure Island (FL) (StatPearls Publishing, 2024). Accessed, September 16, 2024, http://www.ncbi.nlm.nih.gov/books/NBK560881/. [PubMed] [Google Scholar]
- 2. Brownlee E., Wragg R., Robb A., Chandran H., Knight M., and McCarthy L., “Current Epidemiology and Antenatal Presentation of Posterior Urethral Valves: Outcome of BAPS CASS National Audit,” Journal of Pediatric Surgery 54, no. 2 (February 2019): 318–321, 10.1016/j.jpedsurg.2018.10.091. [DOI] [PubMed] [Google Scholar]
- 3. Woolf A. S. and Thiruchelvam N., “Congenital Obstructive Uropathy: Its Origin and Contribution to End‐Stage Renal Disease in Children,” Advances in Renal Replacement Therapy 8, no. 3 (July 2001): 157–163, 10.1053/jarr.2001.26348. [DOI] [PubMed] [Google Scholar]
- 4. Parkhouse H. F., Barratt T. M., Dillon M. J., et al., “Long‐Term Outcome of Boys With Posterior Urethral Valves,” British Journal of Urology 62, no. 1 (July 1988): 59–62, 10.1111/j.1464-410x.1988.tb04267.x. [DOI] [PubMed] [Google Scholar]
- 5. Sarhan O. M., El‐Ghoneimi A. A., Helmy T. E., Dawaba M. S., Ghali A. M., and Ibrahiem E.‐H. I., “Posterior Urethral Valves: Multivariate Analysis of Factors Affecting the Final Renal Outcome,” Journal d'Urologie 185, no. 6 Suppl (June 2011): 2491–2495, 10.1016/j.juro.2011.01.023. [DOI] [PubMed] [Google Scholar]
- 6. Bernardes L. S., Aksnes G., Saada J., et al., “Keyhole Sign: How Specific Is It for the Diagnosis of Posterior Urethral Valves?,” Ultrasound in Obstetrics and Gynecology 34, no. 4 (2009): 419–423, 10.1002/uog.6413. [DOI] [PubMed] [Google Scholar]
- 7. Schwartz G. J., Mun[Combining Tilde]oz A., Schneider M. F., et al., “New Equations to Estimate GFR in Children With CKD,” Journal of the American Society of Nephrology 20, no. 3 (March 2009): 629–637, 10.1681/ASN.2008030287. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8. Harper L., Blanc T., Peycelon M., et al., “Circumcision and Risk of Febrile Urinary Tract Infection in Boys With Posterior Urethral Valves: Result of the CIRCUP Randomized Trial,” European Urology 81, no. 1 (January 2022): 64–72, 10.1016/j.eururo.2021.08.024. [DOI] [PubMed] [Google Scholar]
- 9. Yadav P., Rickard M., Weaver J., et al., “Pre‐Versus Postnatal Presentation of Posterior Urethral Valves: A Multi‐Institutional Experience,” BJU International 130, no. 3 (September 2022): 350–356, 10.1111/bju.15708. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10. Vasconcelos M. A., Simões e Silva A., Dias C., et al., “Posterior Urethral Valves: Comparison of Clinical Outcomes Between Postnatal and Antenatal Cohorts,” Journal of Pediatric Urology 15, no. 2 (April 2019): 167.e1–167.e8, 10.1016/j.jpurol.2018.11.005. [DOI] [PubMed] [Google Scholar]
- 11. Abbo O., Bouali O., Ballouhey Q., et al., “[Is There an Outcome Difference Between Posterior Urethral Valves Diagnosed Prenatally and Postnatally at the Time of Antenatal Screening?],” Progrès en Urologie 23, no. 2 (February 2013): 144–149, 10.1016/j.purol.2012.10.015. [DOI] [PubMed] [Google Scholar]
- 12. Kibar Y., Ashley R. A., Roth C. C., Frimberger D., and Kropp B. P., “Timing of Posterior Urethral Valve Diagnosis and Its Impact on Clinical Outcome,” Journal of Pediatric Urology 7, no. 5 (October 2011): 538–542, 10.1016/j.jpurol.2010.08.002. [DOI] [PubMed] [Google Scholar]
- 13. Gramellini D., Fieni S., Caforio E., et al., “Diagnostic Accuracy of Fetal Renal Pelvis Anteroposterior Diameter as a Predictor of Significant Postnatal Nephrouropathy: Second Versus Third Trimester of Pregnancy,” American Journal of Obstetrics and Gynecology 194, no. 1 (January 2006): 167–173, 10.1016/j.ajog.2005.06.071. [DOI] [PubMed] [Google Scholar]
- 14. Gomez Acevedo H., Rahman M. H., and Moreno M. A., “Sonography 3rd Trimester and Placenta Assessment, Protocols, and Interpretation,” in Statpearls, Treasure Island (FL) (StatPearls Publishing, 2025), Accessed:, May 18, 2025, http://www.ncbi.nlm.nih.gov/books/NBK572062/. [PubMed] [Google Scholar]
- 15. Engel D. L., Pope J. C., Adams M. C., Brock J. W., Thomas J. C., and Tanaka S. T., “Risk Factors Associated With Chronic Kidney Disease in Patients With Posterior Urethral Valves Without Prenatal Hydronephrosis,” Journal d'Urologie 185, no. 6 Suppl (June 2011): 2502–2506, 10.1016/j.juro.2011.01.011. [DOI] [PubMed] [Google Scholar]
- 16. Mustafa H. J., Khalil A., Johnson S., et al., “Fetal Lower Urinary Tract Obstruction: International Delphi Consensus on Management and Core Outcome Set,” Ultrasound Obstet 64, no. 5 (November 2024): 635–650, 10.1002/uog.27684. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17. AIUM Practice Parameter for the Performance of Detailed Second‐ and Third‐Trimester Diagnostic Obstetric Ultrasound Examinations,” Journal of Ultrasound in Medicine 38, no. 12: 3093–3100 (2019), 10.1002/jum.15163. [DOI] [PubMed] [Google Scholar]
- 18. Hutton K. A., Thomas D. F., and Davies B. W., “Prenatally Detected Posterior Urethral Valves: Qualitative Assessment of Second Trimester Scans and Prediction of Outcome,” Journal d'Urologie 158, no. 3 Pt 2 (September 1997): 1022–1025, 10.1016/s0022-5347(01)64379-9. [DOI] [PubMed] [Google Scholar]
- 19. Salomon L. J., Alfirevic Z., Berghella V., et al., “Practice Guidelines for Performance of the Routine Mid‐Trimester Fetal Ultrasound Scan,” Ultrasound in Obstetrics and Gynecology 37, no. 1 (2011): 116–126, 10.1002/uog.8831. [DOI] [PubMed] [Google Scholar]
- 20. Pellegrino C., Capitanucci M. L., Forlini V., et al., “Posterior Urethral Valves: Role of Prenatal Diagnosis and Long‐Term Management of Bladder Function; A Single Center Point of View and Review of Literature,” Frontiers in Pediatrics 10 (2022): 1057092, 10.3389/fped.2022.1057092. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21. Meneghesso D., Bertazza Partigiani N., Spagnol R., Brazzale A. R., Morlacco A., and Vidal E., “Nadir Creatinine as a Predictor of Renal Outcomes in Puvs: A Systematic Review and Meta‐analysis,” Frontiers in Pediatrics 11 (2023): 1085143, 10.3389/fped.2023.1085143. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22. Ruano R., Sananes N., Wilson C., et al., “Fetal Lower Urinary Tract Obstruction: Proposal for Standardized Multidisciplinary Prenatal Management Based on Disease Severity,” Ultrasound in Obstetrics and Gynecology 48, no. 4 (October 2016): 476–482, 10.1002/uog.15844. [DOI] [PubMed] [Google Scholar]
- 23. Ruano R., Dunn T., Braun M. C., Angelo J. R., and Safdar A., “Lower Urinary Tract Obstruction: Fetal Intervention Based on Prenatal Staging,” Pediatric Nephrology 32, no. 10 (October 2017): 1871–1878, 10.1007/s00467-017-3593-8. [DOI] [PubMed] [Google Scholar]
- 24. El‐Ghoneimi A., Harper L., Pierucci U. M., et al., “Management of Patients With Posterior Urethral Valves ‘From the Fetus to Adolescence’: French National Diagnostic and Care Protocol (NDCP),” Orphanet Journal of Rare Diseases 20, no. 1 (May 2025): 225, 10.1186/s13023-025-03712-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25. Pierucci U. M., Paraboschi I., Mantica G., et al., “Antenatal Determinants of Postnatal Renal Function in Fetal Megacystis: A Systematic Review,” Diagn 14, no. 7 (April 2024): 756, 10.3390/diagnostics14070756. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26. Bilgutay A. N., Roth D. R., Gonzales E. T. Jr., et al., “Posterior Urethral Valves: Risk Factors for Progression to Renal Failure,” Journal of Pediatric Urology 12, no. 3 (June 2016): 179.e1–179.e7, 10.1016/j.jpurol.2015.10.009. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27. Alshammari D. M., Dobremez E., Froeliger A., Coatleven F., and Harper L., “Mothers’ Perception of Prenatal Counseling Following Diagnosis of Congenital Anomalies of the Urinary Tract,” Archives de Pédiatrie 28, no. 7 (October 2021): 533–536, 10.1016/j.arcped.2021.08.003. [DOI] [PubMed] [Google Scholar]
- 28. Pecorelli S., Glenisson M., Peycelon M., et al., “Mid‐Term Kidney Function in Boys With Posterior Urethral Valves and a Solitary Functioning Kidney,” Journal d'Urologie 214, no. 3 (September 2025): 289–295, 10.1097/JU.0000000000004612. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.