Adverse perinatal outcomes following the prenatal diagnosis of isolated single umbilical artery in singleton pregnancies: a systematic review and meta-analysis.

OBJECTIVES: A systematic review and meta-analysis was conducted to quantitatively synthesize the current evidence on the association of prenatally diagnosed isolated single umbilical artery (iSUA) in singleton pregnancies with small for gestational age (SGA) neonates and other perinatal outcomes. METHODS: A search of PubMed/Medline, Scopus and The Cochrane Library was conducted, from inception to February 2021, in order to identify studies comparing the risk of SGA and other perinatal adverse outcomes in prenatally diagnosed iSUA singleton pregnancies vs. those with a 3-vessel cord (3VC). The quality of eligible studies was assessed according to the improved Newcastle-Ottawa Scale (NOS). The heterogeneity of results across the studies was tested using the I2 test. Funnel plots and Egger's test were used to assess the possibility of publication bias. Prospero RN: CRD42020182586. RESULTS: The electronic search identified 7,605 studies, of which 11 were selected, including three retrospective cohort and eight retrospective case control studies, overall reporting on 1,533 iSUA cases. The risk of delivering SGA neonates was increased in cases with iSUA (OR: 2.90; 95% CI: 2.02-4.18; p<0.00001; I2=71%). Similarly, iSUA was associated with an increased risk of pregnancy-induced hypertension (PIH) (OR: 2.23; 95% CI: 1.41-3.54; p<0.000; I2=1%), intrauterine death (IUD) (OR: 2.62; 95% CI: 1.43-4.79; p=0.002; I2=0%), preterm birth (PTB) (OR: 2.48; 95% CI: 1.73-3.56; p<0.00001; I2=56%), cesarean section (CS) (OR: 1.64; 95% CI: 1.11-2.41; p=0.01; I2=78%) and admission to neonatal intensive care unit (NICU) (OR: 2.28; 95% CI: 1.52-3.44; p<0.000001; I2=73%). CONCLUSIONS: In prenatally diagnosed iSUA there is a higher risk of SGA, PIH, IUD, PTB, CS and NICU admission. These findings support the value of prenatal diagnosis of iSUA, which may subsequently intensify surveillance for the detection of specific pregnancy complications.

Prenatal diagnosis of familial 2p15 microduplication associated with pulmonary artery stenosis, single umbilical artery and left foot postaxial polydactyly on fetal ultrasound.

OBJECTIVE: We present prenatal diagnosis of familial 2p15 microduplication associated with pulmonary artery stenosis, single umbilical artery and left foot postaxial polydactyly on fetal ultrasound. CASE REPORT: A 34-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed the karyotype of 46,XX. Prenatal ultrasound examination at 21 weeks of gestation showed pulmonary artery stenosis, single umbilical artery and left foot postaxial polydactyly. Repeat amniocentesis was performed at 22 weeks of gestation and array comparative genomic hybridization (aCGH) analysis on the DNAs extracted from amniocytes revealed the result of arr 2p15 (61, 495, 220-62,885,679) × 3.0 [GRCh37 (hg19)] with a 1.391-Mb 2p15 duplication encompassing seven Online Mendelian Inheritance in Man (OMIM) genes of USP34, XPO1, FAM161A, CCT4, COMMD1, B3GNT2 and TMEM17. aCGH analysis on the DNAs extracted from parental bloods confirmed a familial transmission from a normal carrier mother who had no phenotypic abnormality. A 3270-g female baby was delivered at term with mild pulmonary artery stenosis and left foot postaxial polydactyly. The infant had normal physical and psychomotor development when follow-up at age of one year. CONCLUSION: Prenatal diagnosis of fetal structural abnormalities should include aCGH analysis in addition to conventional cytogenetic analysis.

Evaluation of right ventricular function in fetuses with isolated single umbilical artery using spatiotemporal image correlation M-mode.

BACKGROUND: Postnatal outcome of fetuses with isolated single umbilical artery (SUA) is determined mainly by right ventricular function. Our study examined whether there are differences in right ventricular function during the gestation period of fetuses with isolated SUA compared to healthy fetuses. METHODS: A prospective study was conducted on 77 fetuses with isolated SUA and 77 gestational age-matched controls from 22 to 39 weeks. For gestational age grouping, the isolated SUA fetuses and the control fetuses were divided into the second trimester group (22-27 weeks; 43 fetuses) and third trimester group (28-39 weeks; 34 fetuses). The fetal tricuspid annular plane systolic excursion (f-TAPSE) M-mode was applied to the tricuspid annulus, parallel to the ventricular septum, and the amplitude of the resulting wave was assessed using spatiotemporal image correlation (STIC) M-mode. We investigated the possible changes to the STIC M-mode indices during the course of pregnancy in both the isolated SUA and control groups. The relationship between f-TAPSE and gestational age was analyzed. Additionally, the correlations between f-TAPSE and birth weight was analyzed, and the birth weight differences between the isolated SUA and control groups in the third trimester were analyzed according to postpartum results. RESULTS: There was a significant difference in f-TAPSE between isolated SUA and control group in the third trimester (P < 0.05). There were significant correlations between gestational age (GA) and f-TAPSE among control fetuses (R2 = 0.9049; P < 0.01). A significant, positive correlation between GA and f-TAPSE was also found with isolated SUA fetuses (R2 = 0.8108; P < 0.01). The prevalence of small-for-gestational-age (SGA) fetuses and of discordant birth weight fetuses was significantly higher in the isolated SUA group than in the control group. In univariate analysis, the presence of an isolated SUA was associated with lower birth weight (2940 g compared with 3260 g) and with higher prevalence of SGA (13.0% compared with 3.9%; P < 0.01). The correlations between the birth weight and f-TAPSE in the two groups were analyzed in the third trimester, and the correlation in the isolated SUA group was better than that of the control group (R2 was 0.623 and 0.463 in the isolated SUA group and the control group, respectively). CONCLUSIONS: Right ventricular function in isolated SUA is altered as early as in fetal third trimester. STIC M-mode can measure the right heart function of the fetus and may predict isolated SUA with SGA.

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 < 10th , 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.

Embryonic hypocellularity, blastogenetic malformations, and fetal growth restriction.

An association between congenital malformations and fetal growth restriction (FGR) can be largely explained by a relationship with early embryonic hypocellularity. The malformations include the VACTERL association, which is exceptional as a Mendelian syndrome, but is commonly associated with monozygotic twinning, maternal diabetes, and some forms of aneuploidy, all characterized by a small embryo early in development. Parsimony suggests that these different links to VACTERL are related to the hypocellularity as a single common factor, rather than as an expression of three independent pathogenetic processes. A distinct non-genetic pathogenesis is further supported by increased frequencies in the same conditions of a single umbilical artery (SUA), which is also unusual in Mendelian disorders. SUA often involves the atrophy of one artery, which may be facilitated by altered hemodynamics in a smaller embryo, providing a direct link to hypocellularity. Hypocellularity may also explain a possible connection between VACTERL and certain mitochondrial disorders, where reduced energy might slow early cell division and growth, reducing the size of the embryo. © 2016 Wiley Periodicals, Inc.

Application of Umbilical Artery Classification in Complicated Monochorionic Twins.

UNLABELLED: We report our experience on the application of Gratacos' classification in a cohort of monochorionic pregnancies complicated by selective intra-uterine growth retardation based on the Doppler assessment of the umbilical artery. MATERIALS AND METHODS: A retrospective study was conducted on 52 cases of monochorionic twin pregnancies, in which one twin presented an abdominal circumference at or below the 10th percentile for gestational age. Cases were classified into three types according to the umbilical artery Doppler in the smaller twin. Subsequently, patients were divided into two groups: the selective IntraUterine Growth Retardation group and the Twin-to-Twin Transfusion Syndrome (TTTS) group. RESULTS: Of the total 52 cases, 37 were classified as Type I, 12 as Type II, and 3 as Type III cases. In the total group, progressive fetal deterioration of the smaller fetus requiring active management was observed in 66.7% of Type II and 11.1% of Type I cases (p < .001), and in no Type III case. Unexpected fetal death of the smaller twin was observed more frequently in Type III (two cases, 66.7%) than in Types I and II cases (5% and 33%, respectively). Among the 52 cases, TTTS with oligo-polyhydramnios sequence was diagnosed in 10 cases. The remaining 42 cases were therefore defined as selective intra-uterine growth retardation. In the selective IntraUterine Growth Retardation group, results were similar to those obtained for the whole population. CONCLUSIONS: Classification of complicated monochorionic twins based on the umbilical artery Doppler is particularly important for counseling, even when we include TTTS cases, and permits the prediction of clinical evolution and perinatal outcome.

Congenital Malformations Associated With a Single Umbilical Artery in Twin Pregnancies.

A single umbilical artery (SUA) was identified in 1.5% of twin pregnancies. The presence of a SUA in a twin pregnancy was associated with a 50% incidence of fetal anomalies, many of them complex and severe. The embryology and pathophysiological mechanisms associated with a SUA are reviewed. Aneuploidy is relatively common and should be considered, particularly in the presence of associated anomalies. Fetal growth restriction is frequent and preterm delivery is common.

The effects of isolated single umbilical artery on first and second trimester aneuploidy screening test parameters.

OBJECTIVE: Reliability of first and second trimester screening tests largely depends on accurate estimation of maternal serum marker values. Reduced reliability could lead redundant invasive tests or misdiagnosis. Adjustments of serum marker values for confounding factors like insulin-dependent diabetes, maternal weight or maternal rhesus status are essential. We aimed to investigate whether isolated single umbilical artery alters first and second trimester test parameters or not. METHODS: Routine detailed obstetric ultrasonographies performed were retrospectively screened for this study. Among spontaneously conceived singleton pregnancies, women who were found to have single umbilical artery without any additional structural anomalies or aneuploidies were selected. First and second trimester screening test results were accessible for 98 and 102 of the cases with isolated single umbilical artery, respectively. RESULTS: Among first trimester screening test parameters, PAPP-A (pregnancy-associated plasma protein A) MoMs were found significantly higher in isolated single umbilical artery group. AFP MoMs were found significantly elevated in isolated single umbilical artery group in second trimester quadruple tests. CONCLUSION: Existence of single umbilical artery could alter the estimation of MoM values of maternal serum markers. Reliability of prenatal screening tests could be improved by adjusting these parameters in accordance with isolated single umbilical artery.