Single Umbilical Artery Umbilical Cord Is Associated With High-Grade Distal Fetal Vascular Malperfusion.

PURPOSE AND CONTEXT: Umbilical cord abnormalities with clinical signs of cord compromise are frequently associated with fetal vascular malperfusion (FVM). Single umbilical artery (SUA) has been reported to be associated with high-grade FVM in fetal growth restriction but not in an unselected population; our study aimed to address this issue. METHODS: Clinical and placental phenotypes of 55 consecutive placentas with SUA (Group 1) were compared with those of 655 placentas with 3-vessel umbilical cord (Group 2) from patients who were in the second half of their pregnancy. The placentas were histologically examined using hematoxylin and eosin (H&E) staining and CD 34 immunostaining. KEY RESULTS: Several umbilical cord phenotypes and high-grade distal FVM, based on H&E staining and endothelial fragmentation by CD34 were significantly more common in Group 1, whereas decidual clusters of multinucleate trophoblasts were more common in Group 2. Notably, H&E staining or CD34 immunostaining evaluated separately showed that high-grade distal FVM was more common in Group 1 than in Group 2, but the difference was not statistically significant. CONCLUSIONS: SUA predisposes to remote, advanced, and recent high-grade distal villous FVM, with a pathogenesis partly different from that of stasis-induced FVM, likely related to fetal anomalies associated with SUA.

Pregnancy and umbilical cord pathology: structural and functional parameters of the umbilical cord.

Scientific research in the field of physiology and pathology of the umbilical cord is quite limited and imperfect. The purpose of the study was to evaluate the histological architecture of the pathological umbilical cord and investigate the relationship between the main parameters and placental postnatal macromorphometric characteristics, which serve as a reflection of placental dysfunction. Four groups of patients were included, each undergoing a postnatal histological and topographic examination of the umbilical cord: Wharton's jelly edema (10 samples), velamentous cord insertion (10 samples), single umbilical artery (10 samples), and physiological pregnancy (10 samples). Compared to the control group, all newborn groups exhibited changes in umbilical vessel morphology, characterized by an increased Wagenworth index and a decreased Kernohan index. The functional indices of the umbilical vessels were found to be most severely affected in cases of Wharton's jelly edema. In cases of single umbilical artery, the changes in vascular functional parameters indicated their compensatory remodeling with the highest Wagenworth and Kernohan indices of the umbilical vein. Deviation from the normal average placental weight was observed in cases of Wharton's jelly volume pathology or velamentous cord insertion. However, in the case of a single umbilical artery, there were no significant deviations in the macromorphometry of the placenta.

Heterotopic Liver Nodule Compressing a Two-Vessel Umbilical Cord: An Unusual Cause of Intrauterine Fetal Demise.

Heterotopic liver tissue in the umbilical cord is rare, and the outcome is quite unpredictable based on the few reported cases. We present a case of heterotopic liver nodule in the umbilical cord of a midtrimester fetus who died in utero. Although such association has only been reported once, heterotopic nodular tissue in the umbilical cord must be regarded as a potential cause of fetal demise by a mechanism analogous to the more common umbilical cord abnormalities resulting in umbilical vessel compromise.

Placental Findings in Singleton Stillbirths: A Case-control Study.

Aims: This prospective observational study compared placental lesions of stillbirth cases and live birth controls, and aimed to determine the cause of stillbirth. Methods: The study enrolled 85 stillbirths and 85 live births at the time of delivery. Results: There was significantly increased incidence of placental abruption (p = 0.005) and gestational diabetes (p = 0.032) in mothers with stillbirths. Histopathological examination of placenta was significantly abnormal in stillbirths compared with live births (p = 0.004). Delayed villous maturation was significantly more in stillbirths (38.82 vs. 16.47%; p = 0.002). Acute (30.59 vs. 16.47%; p = 0.04) and chronic diffuse villitis (16.47 vs. 4.7%; p = 0.02), chorionic plate acute vasculitis (28.235 vs. 14.11%; p = 0.04) were significantly more in stillbirths. Foetal vascular thrombi in the chorionic plate (30.58 vs. 14.12%; p = 0.02) and avascular villi (24.7 vs. 8.23%; p = 0.006) were significantly more in stillbirths. Conclusion: These abnormal placental patterns could provide information about the etiopathogenisis in stillbirths of unknown aetiology.

Placental abnormalities associated with isolated single umbilical artery in small-for-gestational-age births.

BACKGROUND: Previous studies have shown that pregnancies complicated by placentas with an isolated single umbilical artery (iSUA) are at increased risk for small-for-gestational-age (SGA) births. The etiology of SGA in this population, however, remains unknown. OBJECTIVE: The primary objective of this study was to evaluate whether placental abnormalities in pregnancies with SGA births differ according to the presence of iSUA. STUDY DESIGN: This was an observational study of all women with pathologic examination of the placenta after delivering a non-anomalous, singleton SGA neonate between January 2009 and August 2015. SGA was defined as birthweight less than 10th percentile for gestational age. Women were categorized according to whether they had an iSUA or a three-vessel cord. The following placental pathologies were compared between the groups using bivariable and multivariable analyses: SGA placenta, maternal vascular malperfusion, high grade fetal vascular malperfusion, and chronic villitis. RESULTS: 1833 women were included in the analysis: 34 with iSUA and 1799 with three-vessel cord. More than 85% of women in both groups had at least one placental abnormality. After adjusting for nulliparity and neonatal gender, the presence of iSUA was associated with increased odds of high grade fetal vascular malperfusion (adjusted odds ratio 2.8, 95% confidence interval 1.1-7.5) and decreased odds of maternal vascular malperfusion (adjusted odds ratio 0.2, 95% confidence interval 0.1-0.9). There was no significant association with other pathologic findings. CONCLUSION: Pathologic placental findings associated with SGA birth differed based on umbilical cord composition. The presence of iSUA in an SGA birth was associated with a higher odds of high grade fetal vascular malperfusion abnormalities and lower odds of maternal vascular malperfusion abnormalities, compared to SGA birth with a 3VC.

Isolated single umbilical artery poses neonates at increased risk of long-term respiratory morbidity.

PURPOSE: To investigate whether children born with isolated single umbilical artery (iSUA) at term are at an increased risk for long-term pediatric hospitalizations due to respiratory morbidity. METHODS: Design: a population-based cohort study compared the incidence of long-term, pediatric hospitalizations due to respiratory morbidity in children born with and without iSUA at term. SETTING: Soroka University Medical Center. PARTICIPANTS: all singleton pregnancies of women who delivered between 1991 and 2013. MAIN OUTCOME MEASURE(S): hospitalization due to respiratory morbidity. ANALYSES: Kaplan-Meier survival curves were used to estimate cumulative incidence of respiratory morbidity. A Cox hazards model analysis was used to establish an independent association between iSUA and pediatric respiratory morbidity of the offspring while controlling for clinically relevant confounders. RESULTS: The study included 232,281 deliveries. 0.3% were of newborns with iSUA (n = 766). Newborns with iSUA had a significantly higher rate of long-term respiratory morbidity compared to newborns without iSUA (7.6 vs 5.5%, p = 0.01). Using a Kaplan-Meier survival curve, newborns with iSUA had a significantly higher cumulative incidence of respiratory hospitalizations (log rank = 0.006). In the Cox model, while controlling for the maternal age, gestational age, and birthweight, iSUA at term was found to be an independent risk factor for long-term respiratory morbidity (adjusted HR = 1.39, 95% CI 1.08-1.81; p = 0.012). CONCLUSION: Newborns with iSUA are at an increased risk for long-term respiratory morbidity.

Association Between Isolated Single Umbilical Artery and Perinatal Outcomes: A Meta-Analysis.

BACKGROUND To evaluate the association between the isolated single umbilical artery (iSUA) and perinatal outcomes, including pregnancy outcomes and perinatal complications. MATERIAL AND METHODS We performed a meta-analysis of 15 eligible studies regarding the relationship between the iSUA and perinatal outcomes, including gestational age at delivery, nuchal cord, placental weight, small for gestational age (SGA), oligohydramnios, polyhydramnios, pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), preeclampsia, and perinatal mortality. The overall odds ratios (OR) or standardized mean difference (SMD) were calculated. RESULTS The occurrence of nuchal cord was not found to be different between an iSUA and a three-vessel cord (TVC) fetus. For perinatal complications, the SGA, oligohydramnios, polyhydramnios, GDM, and perinatal mortality showed dramatic difference between women with an iSUA and women with a TVC fetus, which implied that the presence of iSUA significantly increased the risk of perinatal complications. For other perinatal complications, such as PIH and preeclampsia, no significant association was detected. CONCLUSIONS Our meta-analysis suggests that the presence of iSUA would increase the risk of perinatal complications such as SGA, oligohydramnios, polyhydramnios, GDM, and perinatal mortality. Therefore, pregnant women with an iSUA fetus have poorer perinatal outcomes and more attention should be given to the management of their pregnancy compared to women with a TVC fetus.

Isolated single umbilical artery is an independent risk factor for perinatal mortality and adverse outcomes in term neonates.

OBJECTIVE: To determine whether an isolated single umbilical artery (iSUA) is an independent risk factor for perinatal mortality in term neonates with normal estimated fetal weight (EFW) prior to delivery. METHOD: A population-based study was conducted, including all deliveries occurring between 1993 and 2013, in a tertiary medical center. Pregnancies with and without iSUA were compared. Multiple gestations, chromosomal, and structural abnormalities were excluded from the cohort. Only pregnancies delivered at term with normal EFW evaluated prior to delivery were included. Stratified analysis was performed using multiple logistic regression models to evaluate the risk of adverse outcomes and perinatal mortality for iSUA fetuses. RESULTS: During the study period, 233,123 deliveries occurred at "Soroka" University Medical Center, out of which 786 (0.3 %) were diagnosed with iSUA. Different pregnancy complications were more common with iSUA fetuses including: placental abruption (OR = 3.4), true knot of cord (OR = 3.5) and cord prolapse (OR = 2.8). Induction of labor and cesarean delivery were also more common in these pregnancies (OR = 1.5 and OR = 1.9, respectively). iSUA neonates had lower Apgar scores at 1 and 5 min (OR = 1.8, OR = 1.9, respectively) compared to the control group and perinatal mortality rates were higher both antenatally (IUFD, OR = 8.1) and postnatally (PPD, OR = 6.1). CONCLUSION: iSUA appears to be an independent predictor of adverse perinatal outcomes in term neonates.

Impact of isolated single umbilical artery on pregnancy outcome and delivery in full-term births.

AIM: To identify whether an isolated single umbilical artery (ISUA) impacts pregnancy outcome and delivery mode in single and full-term births. METHODS: A retrospective study was carried out on 93,592 pregnant women (singleton pregnancy; full-term birth; no known fetal chromosomal and structural anomalies) who gave birth between January 2011 and January 2012 in 39 hospitals within China. Pregnancy outcomes and modes of delivery were compared between research (313 cases with ISUAs) and comparison groups (1,252 cases with three-vessel cords in a 1:4 ratio randomly matched by parity). RESULTS: The birth weights (3264.71 ± 469.95 g vs 3340.76 ± 434.25 g, P = 0.001), birth lengths (48.51 ± 2.84 cm vs 49.99 ± 1.65 cm, P = 0.000), placental weights (511.31 ± 76.43 g vs 545.31 ± 85.06 g, P = 0.002), umbilical cord lengths (52.64 ± 8.82 cm vs 54.08 ± 7.81 cm, P = 0.002) and Apgar scores within one min of birth (8.83 ± 0.96 vs 9.57 ± 0.75, P = 0.000) of newborn infants were significantly lower in the research than the comparison group; the incidence of small for gestational age (10.94% vs 5.39%, P = 0.000) and low birth weight infants (6.69% vs 1.98%, P = 0.000) were significantly higher in the research group. There was no significant difference in fetal/placental weight, incidence of velamentous cord insertions, 1 min Apgar score < 7, 5 min Apgar score < 7 or vaginal or emergency cesarean delivery rates as a result of fetal factors between the two groups. CONCLUSION: An ISUA is associated with an adverse pregnancy outcome; however does not decrease the rate of vaginal delivery in full-term births.

Maternal Floor Infarction/Massive Perivillous Fibrin Deposition Associated with Hypercoiling of a Single-Artery Umbilical Cord: A Case Report.

Maternal floor infarction is a rare and idiopathic placental disorder associated with adverse obstetric outcomes and a high rate of recurrence in subsequent pregnancies. The pathogenesis of maternal floor infarction is unclear but has been linked to diverse underlying maternal conditions, including gestational hypertension/preeclampsia, immune-mediated diseases, and thrombophilia. Few reports link maternal floor infarction to fetoplacental conditions. We report a 34-week, macerated, growth-restricted male fetus for which the placenta showed maternal floor infarction. The umbilical cord showed excessive coiling and a single umbilical artery. These cord changes are postulated to have resulted in increased placental villous resistance and decreased fetal blood flow, creating a hydrostatic pressure gradient between the villous stroma and the intervillous space. The pressure changes could then lead to trophoblast damage and fibrinoid deposition, contributing to the maternal floor infarction in this case.

Anomalies associated with single umbilical artery at perinatal autopsy.

We evaluated 214 fetuses sent for autopsy with gestational ages ranging from 12 to 39 weeks. Of these, seventeen fetuses (7.9%) had single umbilical artery. Thirteen of these fetuses were aborted after antenatal detection of severe malformations and 4 died in utero. Genito-urinary system (n=6) and central nervous system (n=4) were the most common sites of involvement. Presence of single umbilical artery warrants a detailed evaluation of the fetus for other anomalies.

Detection of single umbilical artery in the first trimester ultrasound: its value as a marker of fetal malformation.

INTRODUCTION: The value of a single umbilical artery (SUA) in first trimester ultrasound is not well established. The aim of our study was to determinate the relevance of diagnosis of single umbilical artery in first trimester ultrasound as an early marker suggesting the presence of malformations or associated chromosomopathies. MATERIAL AND METHODS: Retrospective study of clinical cases of SUA diagnosed at the University Hospital Puerta de Hierro in Madrid (Spain) during the first trimester ultrasound between September 2008 and September 2012. RESULTS: Prevalence of SUA was 1.1% in single pregnancies and 3.3% in twin pregnancies. Sensitivity, specificity, false positive rate, and false negative rate for the finding in the first trimester were 84.2, 99.8, 0.2, and 15.7%, respectively. 17.6% of cases had associated malformations. With an ultrasound in the 16th week most of the cases with significant fetal malformation were diagnosed. DISCUSSION: SUA is a useful marker in the first trimester for fetal malformation pathology, as it will allow detecting a large number of cases with malformations before 20 weeks of gestation.

Placental findings in singleton stillbirths.

OBJECTIVE: To compare placental lesions for stillbirth cases and live birth controls in a population-based study. METHODS: Pathologic examinations were performed on placentas from singleton pregnancies using a standard protocol. Data were analyzed overall and within gestational age groups at delivery. RESULTS: Placentas from 518 stillbirths and 1,200 live births were studied. Single umbilical artery was present in 7.7% of stillbirths and 1.7% of live births, velamentous cord insertion was present in 5% of stillbirths and 1.1% of live births, diffuse terminal villous immaturity was present in 10.3% of stillbirths and 2.3% of live births, inflammation (eg, acute chorioamnionitis of placental membranes) was present in 30.4% of stillbirths and 12% of live births, vascular degenerative changes in chorionic plate were present in 55.7% of stillbirths and 0.5% of live births, retroplacental hematoma was present in 23.8% of stillbirths and 4.2% of live births, intraparenchymal thrombi was present in 19.7% of stillbirths and 13.3% of live births, parenchymal infarction was present in 10.9% of stillbirths and 4.4% of live births, fibrin deposition was present in 9.2% of stillbirths and 1.5% of live births, fetal vascular thrombi was present in 23% of stillbirths and 7% of live births, avascular villi was present in 7.6% of stillbirths and 2.0% of live births, and hydrops was present in 6.4% of stillbirths and 1.0% of live births. Among stillbirths, inflammation and retroplacental hematoma were more common in placentas from early deliveries, whereas thrombotic lesions were more common in later gestation. Inflammatory lesions were especially common in early live births. CONCLUSIONS: Placental lesions were highly associated with stillbirth compared with live births. All lesions associated with stillbirth were found in live births but often with variations by gestational age at delivery. Knowledge of lesion prevalence within gestational age groups in both stillbirths and live birth controls contributes to an understanding of the association between placental abnormality and stillbirth. LEVEL OF EVIDENCE: II.

Twin pregnancies discordant for single umbilical artery.

OBJECTIVE: To evaluate the perinatal outcomes in twin pregnancies discordant for single umbilical artery (SUA). STUDY DESIGN: This was a retrospective cohort study. Our database was searched for all cases of twin gestation and SUA from 1997-2009. We reviewed all the maternal and neonatal records and placental pathology reports. The outcomes of the SUA fetuses were compared to that of their co-twins with a 3-vessel cord (3VC). Paired t test and chi2 tests were used for statistical analyses. RESULTS: We identified 29 cases of twin pregnancies discordant for SUA out of 60,989 ultrasound patients. There were no differences in the prevalence of coexisting anomalies (34% vs. 21%, p = 0.38) between the SUA fetus and the 3VC fetus. The SUA fetus was found to have significantly lower mean birth weight (1,784 +/- 765 g vs. 2,053 +/- 668 g, p = 0.001), 1-minute Apgar score (6.83 +/- 1.89 vs. 7.62 +/- 1.18, p = 0.037), and umbilical artery cord pH (7.27 +/- 0.06 vs. 7.31 +/- 0.07, p = 0.001). The SUA fetus was smaller 79% of the time (p < 0.0001). The SUA fetus achieved a significantly lower percentile (12.77% +/- 21.8 vs. 32.00% +/- 27.56, p = 0.002) when calculating the customized growth potential. CONCLUSION: The fetus affected by an SUA in a twin gestation has impaired fetal growth and neonatal outcomes when compared to its 3VC counterpart.

Single umbilical artery: Does side matter?

INTRODUCTION: The aim of this study was to determine if laterality of an absent umbilical artery (AUA) is associated with specific sonographic findings, chromosomal defects or postpartum birth defects. MATERIALS AND METHODS: In this retrospective cohort study, ultrasound reports and medical records of patients who received an obstetric ultrasound at the University of Iowa Hospitals and Clinics with an identified laterality of the AUA from 1989 to 2007 (n = 405) were reviewed. Rates of sonographic abnormalities between fetuses with a right versus left AUA were compared using Fisher's exact test. Adjustments for confounding were made using logistic regression modeling. The significance level was set at 0.05. RESULTS: Right AUAs on ultrasound demonstrate higher unadjusted rates of ultrasound abnormalities with a higher percentage of fetuses with >1 additional abnormality (51.1 vs. 37.0%; p = 0.0043). The left AUA group had a significantly higher percentage of isolated AUA (63.0 vs. 48.8%; p = 0.004). In a multivariate analysis, a sonographic right AUA was significantly associated with gastrointestinal (GI) and genitourinary (GU) abnormalities. No other ultrasonographic and umbilical artery Doppler abnormalities, chromosomal defects or postpartum birth defects were significantly associated with a specific laterality of the AUA. DISCUSSION: Our study identified a significant association between a right AUA and concomitant fetal GI and GU abnormalities. Contrary to previous reports, we conclude that laterality of the AUA may prove to be an easily identified early marker of fetal abnormalities.