American Journal Of Biomedical Science & Pharmaceutical Innovation
9
https://theusajournals.com/index.php/ajbspi
VOLUME
Vol.05 Issue08 2025
PAGE NO.
9-12
10.37547/ajbspi/Volume05Issue08-02
Review of Literature on Epidemiology, Diagnostics,
Complications of Umbilical Cord Pathology and
Management Tactics
Tojiyeva Nigina Iskandarovna
Assistant, department of Obstetrics and gynecology #1, Samarkand State Medical University, Uzbekistan
Received:
17 June 2025;
Accepted:
13 July 2025;
Published:
15 August 2025
Abstract:
This review systematizes current knowledge about umbilical cord abnormalities (UCAs)
—
a
heterogeneous group of anomalies including length abnormalities, number of vessels, attachments, nodes, cysts,
and vascular malformations. Based on the analysis of scientific literature (2000
–
2024), the epidemiological data
are presented: UCAs occur in 15
–
35% of pregnancies, with single umbilical artery (SUA)
—
in 0.5
–
5%, velmen
insertion
—
up to 50% in monochorionic twins, and true nodes
—
in 0.3
–
1.2%. The review details complications:
fetal growth restriction (FGR), chronic and acute hypoxia, antenatal death, risks during childbirth (vascular rupture
in vasa praevia, asphyxia). Particular attention is paid to early diagnostic methods: ultrasound with Doppler (blood
flow assessment, EAP), color Doppler mapping (Velmen attachment), 3D/4D ultrasound in STIC mode (nodes,
spatial anomalies), CTG monitoring. Differentiated management tactics are substantiated: from dynamic
observation at low risk to planned cesarean section for vasa praevia or IUGR. It is emphasized that timely
diagnostics and an individualized approach reduce perinatal mortality and improve outcomes.
Keywords:
Umbilical cord abnormalities; Single umbilical artery; Velamentous cord insertion; Vasa previa; True
umbilical cord knot; Umbilical cord entanglement; Umbilical cord cysts; Umbilical artery Doppler; Prenatal
diagnosis; Pregnancy complications; Perinatal outcomes; 3D/4D ultrasound; Fetal growth restriction (FGR);
Pregnancy management; Cord structure pathology.
Introduction:
Umbilical cord abnormalities (UCAs) are
a heterogeneous group of anomalies that include
deviations in length, number of vessels, type of
attachment, presence of nodes, cysts and vascular
malformations. Despite the fact that many UCAs have
no clinical consequences, some types are associated
with an increased risk of fetal growth restriction (FGR),
hypoxia, birth asphyxia, stillbirth and the need for
emergency operative delivery [1, 2].
The prevalence of UCAs in the population varies,
reaching significant numbers, which emphasizes the
relevance of the problem for perinatology [3, 4].
Modern methods of prenatal diagnostics, primarily
ultrasound, play a key role in early detection and
determination
of
pregnancy
and
childbirth
management tactics [5, 6].
The purpose of the review
: to systematize modern
data on the prevalence, diagnosis, complications and
management tactics of pregnant women with various
umbilical cord abnormalities.
METHODS
An analysis of scientific literature data published for the
period 2000-2024 was conducted using the PubMed,
MEDLINE, Scopus, Cochrane Library, and eLibrary
databases. Key words: "umbilical cord pathologies",
"umbilical
cord
anomalies",
"umbilical
cord
entanglement", "true cord knot", "velmen insertion of
the umbilical cord", "diagnosis of umbilical cord
pathologies", "pregnancy complications with umbilical
cord anomalies". Systematic reviews, meta-analyses,
randomized controlled trials, large cohort studies, and
clinical guidelines were selected.
RESULTS
The overall incidence of UCAs, according to ultrasound
and pathological studies, ranges from 15% to 35% of all
American Journal of Applied Science and Technology
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American Journal of Applied Science and Technology (ISSN: 2771-2745)
pregnancies [3, 7]. Cord entanglement around the
fetus's neck is the most common anomaly, occurring in
21-34% of term births, with multiple entanglements
recorded in 2-8% of cases [1, 8]. Single umbilical artery
(SUA) occurs with a frequency of 0.5-1% in singleton
pregnancies and up to 5% in multiple pregnancies [2,
9]. In 20-30% of cases, SUA is combined with other
congenital
fetal
anomalies
(cardiovascular,
genitourinary, gastrointestinal tract, central nervous
system) or chromosomal pathologies (trisomy 18, 13)
[2, 10, 11]. Velmen (membranous) insertion of the
umbilical cord is observed in approximately 1% of
singleton pregnancies, but its frequency increases to
15% in multiple pregnancies and up to 50% in
monochorionic twins [12, 13].
True umbilical cord knots are less common, occurring
in approximately 0.3-1.2% of pregnancies, but their
clinical significance is high [14].
Short umbilical cord (<35-40 cm) - 4-6%, long umbilical
cord (>70-80 cm) - 5-7% [1, 15]. Umbilical cord cysts
(true and false) are detected in 0.4-3.4% of cases [16].
Intrauterine growth retardation (especially with a
single umbilical artery without associated anomalies,
velmen attachment, thrombosis) is one of the common
antenatal complications in umbilical cord pathologies
[2, 9, 12]; chronic fetal hypoxia; spontaneous abortions
(more often with early detection of SUA or multiple
cysts) [16] also occur in various organic pathologies of
the umbilical cord. Antenatal fetal death occurs with
true knots, thrombosis, severe varicose veins, tight
multiple entanglement [14, 17]. Acute fetal
hypoxia/asphyxia during labor occurs with tension of a
short umbilical cord, tightening of a true knot, tight
entanglement, prolapse of the umbilical cord [1, 8, 14];
placental abruption is the most serious complication
that occurs with a short umbilical cord or tension with
a velmen insertion [12]; rupture of the umbilical vessels
with fatal bleeding in the fetus is most typical for a
velmen insertion, especially with vasa previa [12, 13]; a
prolonged course of the second stage of labor occurs
due to a short umbilical cord, which is expressed in the
need for an emergency cesarean section [1, 8].
Children born with these pathologies have an increased
risk of low scores on the Apgar scale, an increased need
for neonatal resuscitation, and they can also develop
hypoxic-ischemic encephalopathy and the worst -
stillbirth [1, 14, 17]. The risk of perinatal mortality with
a true umbilical cord knot increases by 4 times [14].
Modern methods of examination and early detection of
umbilical cord pathologies are intended to prevent
these complications. Standard 2D ultrasound (II
trimester, 18-22 weeks) is the main screening method.
It allows diagnosing vascular pathology (assessment of
the number of vessels in the cross-section), cysts,
attachment anomalies (especially with a thorough
examination of the placental disk), length (indirectly by
the presence of loops, their number), varicose veins [5,
6, 9]. Color Doppler mapping (CDM) and power Doppler
(PD) are new methods, especially in the conditions of
Uzbekistan. These methods are critically important for
confirming vascular anomalies, diagnosing Velmen
attachment (visualization of vessels running in the
membranes), assessing blood flow in the umbilical
vessels and cysts, differentiating true and false nodes
[5, 12, 13]. Doppler ultrasound allows us to study the
resistance index, systolic-diastolic ratio and pulsation
index in the umbilical artery, which makes it possible to
assess the state of fetoplacental blood flow. An
increase in resistance indices predicts unfavorable
perinatal outcomes [6, 9, 18]. The absence or reverse
diastolic blood flow is an indication for emergency
delivery.
3D / 4D ultrasound with reconstruction in the STIC
(Spatio-Temporal Image Correlation) mode allows us to
obtain a detailed image of the umbilical cord in volume,
improving the diagnosis of nodes, attachment features
and spatial relationships with the fetus [5, 19].
Cardiotocography (CTG) makes it possible to monitor
the condition of the fetus in the third trimester and
during labor. Allows to identify signs of hypoxia
(decelerations, decreased variability), especially if
there is a suspicion of entanglement or knot [1, 8], this
makes it possible to avoid serious complications and
improve birth outcomes.
Prenatal
karyotyping/chromosomal
microarray
analysis (CMAA) is recommended when a single
umbilical artery is detected in combination with other
ultrasound markers of fetal abnormalities or
intrauterine
growth
retardation
to
exclude
chromosomal pathology [2, 10].
Magnetic resonance imaging (MRI) of the fetus is rarely
used, in complex diagnostic cases, for example, to
clarify the nature of large cysts or vascular relationships
if vasa praevia is suspected with a velmen attachment
[20].
The principles of managing patients with umbilical cord
pathology include, first of all, clarifying the diagnosis. A
thorough ultrasound with color Doppler/ED and
Doppler to confirm the type of pathology and assess
fetoplacental blood flow [5, 6]. Extended echographic
and genetic screening is used when a single umbilical
artery or umbilical cord cysts are detected with a
mandatory detailed examination of the fetal anatomy
(echocardiography, neurosonography, etc.). In the
presence of combined markers, a consultation with a
geneticist and invasive diagnostics are prescribed [2, 9,
American Journal of Applied Science and Technology
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American Journal of Applied Science and Technology (ISSN: 2771-2745)
10, 16]. Regular ultrasound monitoring (fetal growth,
amniotic fluid volume, Doppler) and CTG allow
monitoring the condition of both the fetus and the
mother. The frequency is determined by the type of
pathology and the presence of complications (IUGR,
impaired blood flow). In the case of an uncomplicated
single umbilical artery or false nodes - standard
monitoring. In case of velmen attachment, true nodes,
short umbilical cord, blood flow disorders - enhanced
monitoring (weekly or more often in the third
trimester) [1, 6, 12]. Treatment of placental
insufficiency in case of IUGR and blood flow disorders
is carried out in hospital, vascular therapy and
hemostasis control are indicated [18].
In most umbilical cord pathologies (entanglement
without blood flow disorders, single umbilical artery
without intrauterine growth restriction/anomalies),
vaginal delivery is possible under careful continuous
CTG monitoring [1, 8].
Indications for planned cesarean section (CS):
Confirmed velum insertion with risk of vasa praevia
(especially with low placenta/presentation) [12, 13];
severe intrauterine growth restriction against the
background of umbilical cord pathology with blood
flow disorders; some cases of true knots (debatable,
individual decision) [14]; short umbilical cord less than
40 cm.
If signs of acute fetal hypoxia appear according to CTG
during labor, rupture of vessels (vasa praevia), or
prolapse of the umbilical cord, an emergency CS is
performed [1, 13].
In case of entanglement or suspicion of a knot, careful
management of the second period is necessary
(exclusion of pushing "for contractions", episiotomy),
and readiness for an emergency CS. In case of a velem
attachment, extremely careful opening of the fetal
bladder (amniotomy) is contraindicated if vasa praevia
is suspected [12, 13]. Discussion. Pathologies of the
umbilical cord structure are a frequent finding in
obstetric practice. Despite the often benign course of
many anomalies (false knots, isolated single umbilical
artery without IUGR, loose entanglement), their
diagnosis requires increased attention due to the
potential risk of serious ante- and intranatal
complications. Modern ultrasound methods, especially
those using Doppler technologies and 3D/4D
reconstruction, are the cornerstone of prenatal
diagnostics of umbilical cord pathologies, allowing to
identify most significant anomalies in the second
trimester [5, 6, 19]. The key aspect of management is a
differentiated approach: from standard observation at
low risk to intensive monitoring and planned operative
delivery at high risk (Velmen insertion, vasa praevia,
true nodes with impaired blood flow, severe IUGR
against the background of a single umbilical artery) [1,
12, 14]. The importance of early diagnosis of vasa
praevia cannot be overestimated, since timely planned
CS prevents catastrophic bleeding in the fetus [13].
Further research should be aimed at clarifying the
prognostic significance of various Doppler parameters
in different pathologies, developing risk stratification
algorithms and optimizing the timing of delivery.
CONCLUSION
Pathologies of the umbilical cord structure are a
significant perinatal risk factor. Knowledge of their
prevalence, pathogenesis of possible complications
and mastery of modern diagnostic methods
(ultrasound with Doppler, 3D/4D) are mandatory for a
practicing obstetrician-gynecologist. Early detection,
careful assessment of the fetus (exclusion of combined
anomalies, monitoring of growth and blood flow) and
an individualized approach to planning the timing and
method of delivery can significantly improve perinatal
outcomes. Particular attention should be paid to
diagnostics and management tactics in case of vasa
praevia insertion (risk of vasa praevia) and conditions
associated with acute intranatal hypoxia.
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