Is echocardiography necessary for all single umbilical artery fetuses? A retrospective study in a selected Chinese population

Diagnosis of single umbilical artery and risk of foetal congenital malformations by prenatal ultrasound: a retrospective study

BACKGROUND

Single umbilical artery (SUA) is strongly associated with foetal structural abnormalities; however, the exact pattern of this association has not been described. We aimed to investigate the occurrence of malformations in singleton pregnancies with SUA in China and to study the association between the absent side of the umbilical artery and foetal malformations.

METHODS

This was a retrospective study of singleton pregnancies for which routine first-trimester anatomical screening was performed at 11+ 0-13+ 6 gestational weeks and, if the pregnancy continued, a second-trimester scan was performed at 20+ 0-24+ 0 weeks. Data were extracted from records at the referral centre, the Obstetrics and Gynecology Hospital of Fudan University, between January 2011 and April 2019 (n = 47,894). Using logistic regression, the odds ratios (OR) with 95% confidence intervals (CIs) were calculated for malformations associated with SUA.

RESULTS

The incidence of SUA in our study was 2.0% (970/47,894). Of all foetuses with SUA, 387 (39.9%) had structural malformations. The malformation type varied, with cardiovascular complications being the most common. A robust association was observed between SUA and oesophageal stenosis or atresia (OR: 25.33), followed by cardiovascular (OR: 9.98-24.02), scoliosis (OR: 18.62), genitourinary (OR: 2.45-15.66), and brain malformations (OR: 4.73-9.12). The absence of the left umbilical artery (n = 445, 45.9%) was consistent with that of the right umbilical artery (n = 431, 44.4%). Furthermore, a significantly higher rate of an absent right than the left umbilical artery (p<0.01) was observed in SUA with foetal abnormalities than in SUA with no malformations.

CONCLUSIONS

Overall, we observed a higher risk of various specific malformations in foetuses with SUA, and a strong association between SUA and oesophageal stenosis or atresia. The absence of the right umbilical artery was most common in foetuses with SUA and structural malformations. This study provides a reference for ultrasonographers in conducting foetal structural screening for pregnant women with SUA.

Incidence of congenital heart disease in fetuses diagnosed with single isolated umbilical artery. Systematic review and meta-analysis

OBJECTIVE

To estimate the proportion of heart disease in fetuses with a prenatal diagnosis of a single isolated umbilical artery.

METHODS

We performed a search strategy in MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to the present. We assessed the risk of bias and performed a meta-analysis. We completed the subgroup analysis according to the region.

RESULTS

We found 1384 studies by the search strategy. After carefully reviewing the full-text, 15 studies were included. A total of 2008 fetuses with a single isolated umbilical artery were included, and 177 had cardiac malformations. There was an overall incidence of 9% 95%CI (0.05-0.14) I2 90%. The incidence by country of origin was between 5% and 19%. The most common heart disease reported was a ventricular septal defect. Seven studies were found describing 25 cases. We described other malformations, such as tetralogy of Fallot, coarctation of the aorta, and hypoplastic left ventricle, among others.

CONCLUSION

The incidence of congenital heart disease in fetuses with a single isolated umbilical artery was high. In addition, half of these correspond to significant heart disease. Based on the above, we suggest that fetuses with a single isolated umbilical artery should have a complete anatomic evaluation emphasizing cardiac evaluation.

Risk of adverse pregnancy outcome in isolated single umbilical artery diagnosed at the mid-trimester anomaly scan: a large Danish retrospective cohort study

OBJECTIVE

To examine the association of isolated single umbilical artery (iSUA) confirmed at the mid-trimester anomaly scan and adverse pregnancy outcome and congenital malformations with up to 10 years postnatal follow up.

METHODS

This retrospective cohort study included 116,501 singleton pregnancies consecutively enrolled in first trimester screening for aneuploidies and mid-trimester anomaly scan at three University Hospitals in the Capital Region of Copenhagen, Denmark.Data from the Danish Fetal Medicine Database (2008-2017) were verified by manually scrutinizing pre- and postnatal records. The main outcomes of interest were intrauterine fetal demise (IUFD), small for gestational age (SGA), preterm delivery, cesarean section and unrecognized pre- and postnatal congenital malformations.

RESULTS

In total, 775 pregnancies with iSUA were identified. Isolated SUA were associated with a significantly increased risk of IUFD (OR 4.16, 95% CI 2.06-8.44), SGA < 3^rd centile (aOR 2.41, 95% 1.85-3.14) and SGA < 10^th centile (aOR 1.84, 95% CI 1.53-2.21), but not with preterm delivery or cesarean section. The laterality of the missing artery was not associated with SGA. In total, 4.3% of pregnancies with iSUA had unrecognized congenital malformations. 1.5% with iSUA had congenital cardiovascular malformations, which were considered minor.

CONCLUSION

Isolated SUA is associated with IUFD and SGA, supporting surveillance during third trimester. If, during the mid-trimester scan, the sonographer achieves thorough, extended cardiac views and finds no additional malformation other than SUA, fetal echocardiography seems not to be needed.

Associated factors for prenatally diagnosed fetal congenital heart diseases

OBJECTIVE

Current studies have suggested that fetal congenital heart diseases (CHDs) are caused by various factors. However, few data in this field is available in China. This study aimed to detect associated factors of prenatally diagnosed fetal CHD in a large sample in China.

STUDY DESIGN

Pregnant women who underwent fetal echocardiography were recruited in our hospital between May 2018 and September 2019. The maternal sociodemographic and lifestyle characteristics and some fetal factors were obtained. We used forward stepwise logistic regression analysis to assess risk of fetal CHD associated with various factors.

RESULTS

A total of 5024 subjects were enrolled, of whom 875 had CHD fetuses. Among the fetal CHD group (N = 875), critical CHDs account for 27%, of which Tetralogy of Fallot is the most (7.1%), followed by coarctation of aorta (4.0%), double-outlet right ventricle (2.9%). The forward stepwise logistic regression models revealed that history of spontaneous abortion (OR = 1.59, 95% CI 1.33-1.91, P = 0.000), upper respiratory tract infection during early pregnancy (OR = 1.30, 95% CI 1.04-1.62, P = 0.020), mental stress during early pregnancy (OR = 2.37, 95% CI 1.15-4.91, P = 0.020), single umbilical artery (OR = 2.30, 95% CI 1.18-4.51, P = 0.015), and paternal smoking (OR = 1.21, 95% CI 1.02-1.44, P = 0.027) are positively associated with an increased risk of fetal CHD.

CONCLUSION

We identified several factors positively associated with fetal CHD. These findings suggest that it is important to strengthen healthcare and prenatal counseling for women with these factors.

Comparative study of umbilical cord cross-sectional area in foetuses with isolated single umbilical artery and normal umbilical artery

Single umbilical artery (SUA) is one of the most common prenatal diagnoses in cases of foetal abnormality. This prospective study evaluated 77 foetuses with isolated SUAs and 77 healthy foetuses, both at 22-39 gestational weeks. We categorised gestational age into the second and third trimesters, measured the umbilical arterial blood flow parameters and calculated the umbilical vein (UV) area, umbilical artery (UA) area and UV area/UA area ratio. In the second and third trimesters, a higher UA area was obtained in the isolated SUA group than in the control group (p < .01). Furthermore, the isolated SUA group had a lower UV area/UA area ratio than the control group (p < .01), and a positive linear correlation was found between gestational age and UV area in both groups (p < .01). The presence of isolated SUAs was associated with low birth weight and a high prevalence of small for gestational age.IMPACT STATEMENTWhat is already known on this subject? Single umbilical artery (SUA) is one of the most common prenatally diagnosed foetal abnormalities and approximately 80% foetuses with SUA have isolated SUA, which is a soft indicator of chromosome abnormalities, congenital malformations and premature birth. Umbilical cord cross-sectional area can be evaluated prenatally by ultrasound imaging. Normal values increase with gestational age and foetal size in single pregnancies. Changes in umbilical cord thickness have been associated with complications during pregnancy.What do the results of this study add? The correlation between gestational age and umbilical vein area in the isolated single umbilical artery (SUA) group and control group was better than that between gestational age and umbilical artery area. UA area increased significantly in both groups before 28 weeks but not after 28 weeks, particularly in the isolated SUA group.What are the implications of these findings for clinical practice and/or further research? The study provides a reliable basis for maternal foetal monitoring during pregnancy in the isolated SUA and control groups. Objective assessment of the occurrence and development of foetuses with isolated single umbilical artery was performed.

Anatomical Survey Versus Fetal Echocardiograms for Diagnosis of Cardiac Defects with a Single Umbilical Artery Cases: A Retrospective Cohort Study and Diagnostic Meta-analysis

OBJECTIVE

To determine the utility of fetal echocardiography in diagnosing cardiac defects in fetuses with a single umbilical artery (SUA).

METHODS

A retrospective cohort study of prenatally diagnosed SUA was conducted over a 10-year period at a single institution. Cardiac anatomy on detailed anatomical survey was compared with fetal echocardiogram for fetuses with prenatally diagnosed SUA. A diagnostic meta-analysis of studies comparing fetal anatomical survey to fetal echocardiogram in fetuses with SUA between 2010 to 2019 was also performed.

RESULTS

Three hundred and twenty fetuses with SUA were identified, 113 of which had completed both ultrasound and echocardiography. There were 36 cases of cardiac defects on prenatal echocardiogram and all had abnormal anatomical ultrasounds. There were zero cases of abnormal cardiac exams (0%) when the cardiac views on anatomical survey were normal. The sensitivity, specificity, positive predictive value and negative predictive value of ultrasound were 100%, 77%, 73% and 100%, respectively. A summary ROC curve demonstrated a high predictive value of routine anatomic survey for cardiac defects (AUC: 0.99).

CONCLUSION

Anatomic survey is highly predictive in the detection of cardiac defects in fetuses with SUA. Fetal echocardiogram is unnecessary in SUA when cardiac views are normal on ultrasound.