Screening infants with an isolated single umbilical artery for renal anomalies: nonsense?

Risks of Renal Anomalies and Urinary Tract Infections in Neonates With Single Umbilical Artery

Background Our study aims to evaluate the characteristics of congenital anomalies of kidneys and urinary tracts (CAKUT) and urinary tract infection (UTI) in babies with single umbilical artery (SUA) and to identify factors associated with these outcomes. Methods We performed a 15-year retrospective analysis on babies who were born ≥34 weeks with SUA between 2006 and 2020. Relevant clinical information on obstetrics and neonatal examinations, UTIs, and imaging of the urinary systems was evaluated. Results The frequency of SUA in newborns was 3.28 per 1,000 deliveries. The majority (271/291; 93.1%) of patients had kidney ultrasound, and 19 (7.0%) had CAKUT. Hydronephrosis (n = 11, 57.9%) was the commonest CAKUT, followed by unilateral kidney agenesis (n = 3, 15.8%), horseshoe kidney (n = 2, 10.5%), and right low-lying kidney (n = 2, 10.5%). Most significant CAKUT (including solitary kidney and urinary tract obstruction) could be detected during the antenatal period. Congenital heart defect (OR 4.93, 95% CI 1.59-15.34), limbs (OR 9.77, 95% CI 1.53-62.44), and sacral abnormalities (OR 5.06, 95% CI 1.25-20.55) were associated with CAKUT. Six (2.1%) developed UTIs during the study period, with the majority below two years old. The presence of CAKUT was associated with the development of UTI after adjustment (adjusted HR 10.28, 95% CI 1.86-56.83). Conclusions The overall prevalence of CAKUT was 7.0% in patients with SUA, and the majority of significant CAKUT was identified during the antenatal period. Congenital heart defects, limbs, and sacral abnormalities were associated with CAKUT. UTI occurred in 2.1% of patients.

Differences in perinatal outcomes according to forming period of single umbilical cord in singleton pregnancy

OBJECTIVES

The aim of this study was to establish the frequency and associations of single umbilical artery (SUA) diagnosed until the first vs second or third trimester.

METHODS

A retrospective cohort study was conducted on singleton pregnancies at a tertiary perinatal center. All women underwent both the first and second trimester scans in which the number of arteries in the umbilical cord was routinely documented. SUA was classified as aplastic type when the diagnosis was made in the first trimester and as occlusion type when diagnosed in the second or third trimester. Adverse perinatal outcome was calculated as occurrence of fetal death, birthweight centile < 10^th , or Apgar score at 5 minutes < 7.

RESULTS

A total of 8675 women underwent ultrasound examinations during the study period. Of the 32 SUA cases, 17 (0.2%) were of the aplastic type and 15 (0.2%) of the occlusion type. Congenital anomalies were more in aplastic than in occlusive SUA (58.8% vs 20%, .043). The occlusive SUA had higher postnatal coiling index (0.3 vs 0.2, .034) and diagnosis of hypercoiled cord (46.7% vs 5.9%, .013) than the aplastic type.

CONCLUSIONS

The different gestational age at diagnosis and coiling characteristics suggest two types of SUA, namely, aplastic and occlusion types, which are associated with differences in perinatal outcomes.

Association of isolated single umbilical artery with perinatal outcomes: Systemic review and meta-analysis

Objective

The aim of this study was to evaluate the association between prenatally diagnosed isolated single umbilical artery (iSUA) and perinatal outcomes.

Methods

We searched Medline, Embase, the Cochrane Library, and KoreaMed from inception to January 2016, with no language or regional restrictions, for cohort and case-control studies reporting on the relationship of iSUA and perinatal outcomes. We assessed the odds ratios (ORs) and 95% confidence intervals (CIs) for the occurrence of small for gestational age, preterm birth, pregnancy-induced hypertension, neonatal intensive care unit admission, and perinatal mortality in fetuses with iSUA compared with those in fetuses with three vessel cord.

Results

Eleven articles totaling 1,731 pregnancies with iSUA met the selection criteria. Studies varied in design, quality, outcome definition, and results. Meta-analysis carried out within predefined groups showed that the presence of an iSUA was associated with small for gestational age (OR, 2.75; 95% CI, 1.97 to 3.83; P<0.00001), preterm birth (OR, 2.10; 95% CI, 1.72 to 2.57; P<0.00001), pregnancy-induced hypertension (OR, 1.62; 95% CI, 1.00 to 2.63; P=0.05), neonatal intensive care unit admission (OR, 2.06; 95% CI, 1.33 to 3.19; P=0.001), and perinatal mortality (OR, 2.29; 95% CI, 1.32 to 3.98; P=0.003).

Conclusion

Pregnancies complicated by iSUA are at increased risk for small for gestational age, preterm birth, pregnancy-induced hypertension, neonatal intensive care unit admission and perinatal mortality. Further, large prospective cohort studies are required to improve the quality of prenatal counseling and the neonatal care for pregnancies with iSUA.

The impact of isolated single umbilical artery on labor and delivery outcome

OBJECTIVE

Data regarding the association between isolated single umbilical artery (SUA) and pregnancy outcome are inconsistent and mainly address the risk of pregnancy complications. Thus, we aimed to focus on the association between isolated SUA, and labor and delivery.

METHODS

We conducted a case-control study of all singleton pregnancies diagnosed with isolated SUA (no known chromosomal/structural anomalies/fetal growth restriction) attempting vaginal delivery. Obstetric and neonatal outcome was compared with that of a control group of pregnancies with a three-vessel cord in a 1:2 ratio matched by parity. Composite adverse outcome included the following: Cesarean section (CS) and/or operative delivery due to non-reassuring fetal heart rate (NRFHR), prolonged neonatal admission, low Apgar score and umbilical artery pH < 7.2.

RESULTS

Out of 34 196 deliveries, 162 (0.5%) were diagnosed with SUA, and 91 (0.27%) were diagnosed with isolated SUA. Isolated SUA was associated with a higher rate of CS due to NRFHR (5.5% vs 1%, p = 0.02), small for gestational age (SGA) (14.3% vs 4.9%, p = 0.009), lower birth weight, and a higher rate of composite adverse outcome (20.9% vs 8.8%, p = 0.005). On multivariable analysis, isolated SUA was independently associated with an increased risk for composite adverse outcome (OR 2.34, 95% CI 1.05-5.21).

CONCLUSION

Isolated SUA is associated with increased risk for CS due to NRFHR and increased rate of SGA.

The Stillbirth Collaborative Research Network (SCRN) placental and umbilical cord examination protocol

The Stillbirth Collaborative Research Network (SCRN) was organized to study the scope and causes of stillbirth (SB) in the United States. The objective of this report is to describe the approach used for the placental examination performed as part of the study. The SCRN consists of a multidisciplinary team of investigators from five clinical sites, the National Institute of Child Health and Human Development, and the Data Coordination and Analysis Center. The study is a population-based cohort and nested case-control study, with prospective enrollment of women with SB and live births (LB) at the time of delivery. Detailed and standardized postmortem examination was performed on SB and placental examination in both groups. A total of 663 women with SB and 1932 women with LB were enrolled into the case-control study. In the SB group, there were 707 fetuses. Of these cases, 654 (98.6%) had placental examination. Of these LB controls, 1804 (93.4%) had placental examination. This is the largest prospective study to include population-based SB and LB, using standardized postmortem and placental examination, medical record review, maternal interview, collection of samples, and a multidisciplinary team of investigators collaborating in the analyses. Thus it has the potential to provide high-level evidence regarding the contribution of placental abnormalities to stillbirth.

Single umbilical artery in fetopathological investigations

Single umbilical artery (SUA) is a relatively common malformation that may call attention to the possibility of associated malformations (often chromosome aberrations). The current study aimed at surveying malformations associated with SUA on the basis of fetopathological investigations, analyzing the role of history, summarizing the clinically important factors emerging together with this malformation. In this study, we processed the details of 204 cases in which SUA was confirmed fetopathologically after miscarriage or induced abortion between 1990 and 2007. In our sample, SUA occurred in 7.38% of the cases. The history was positive in almost 30% of the cases. The majority of the cases had a positive obstetric and the minority of them a positive genetic history. The highest association of SUA with other malformations was found for craniospinal ones, but an association with cardiovascular malformations should also be mentioned. Regarding the individual types of malformation, SUA was most commonly associated with hydrocephalus, but Potter's sequence, trisomy 21, and atrioventricular septal defect also reached a higher rate in associated SUA. Previously published articles dealing with associated malformations found that urogenital malformations were most commonly associated with SUA. 'Itemizing' the different non-chromosomal malformations in association with SUA, we found that hydrocephalus, Potter's sequence, and atrioventricular septal defect were the most frequent malformations, while in earlier studies, the association with non-chromosomal malformations such as vertebral malformations, imperforated anus, cheilognathopalatoschisis, and renal agenesis occurred more frequently than usual.