Version July 2025
INTRODUCTION —
An omphalocele is a midline abdominal wall defect of variable diameter at the base of the umbilical cord. The defect is covered by a three-layer membranous sac consisting of amnion, Wharton's jelly, and parietal peritoneum, unless the sac has ruptured. The umbilical cord vessels insert at the apex of the sac, which typically contains herniated abdominal contents (picture 1). Depending on the contents, omphaloceles are categorized as either liver-containing or non-liver-containing. Small defects generally can be closed in the first 24 to 72 hours of life. Large defects usually require some type of silo in the first 24 hours and delayed closure.
This topic will discuss issues related to omphalocele, primarily focusing upon prenatal diagnosis and pregnancy management. The other major fetal abdominal wall defect, gastroschisis, is reviewed separately. (See "Gastroschisis".)
EMBRYOLOGY AND PATHOGENESIS
Normal embryologic development of the abdominal wall — During the fourth to fifth week of embryonic development (6 to 7 weeks of gestation), the flat embryonic disk folds in four directions and/or planes: cephalic, caudal, and right and left lateral. Each fold converges at the site of the umbilicus, thus obliterating most of the extraembryonic coelom. The lateral folds form the lateral portions of the abdominal wall, and the cephalic and caudal folds make up the epigastrium and hypogastrium [1,2].
During the sixth week of development (8 weeks of gestation), the abdominal cavity temporarily becomes too small to accommodate its growing contents, resulting in protrusion of the midgut into the residual extraembryonic coelom at the base of the umbilical cord. This temporary herniation involves 90 degrees of counterclockwise rotation of the midgut around the superior mesenteric pedicle and is called physiologic midgut herniation. It is sonographically evident in the 9th to 11th postmenstrual weeks (up to crown rump length 45 mm) (image 1). Reduction of the hernia involves further rotation to 270 degrees in the abdominal cavity and normally occurs by the 12th postmenstrual week; thus, midgut herniation is no longer physiologic beyond the 12th week [3].
In contrast to the bowel, the liver does not undergo physiologic migration outside of the abdominal cavity during development. Therefore, the liver is never present in physiologic midgut herniation.
Pathogenesis of omphalocele — The pathogenesis of omphalocele has not been definitively established, but two mechanisms have been proposed:
●The extraembryonic gut fails to undergo the obligatory 270 degree counterclockwise rotation back into the abdomen, resulting in a simple, small, midline omphalocele [1,2,4].
●Failure of the left and right lateral folds to close normally creates a large abdominal wall defect through which contents of abdominal cavity (including the liver) can herniate [1,2]. In addition, the rectus abdominis muscles insert laterally into the costal margins instead of meeting in the midline at the xiphoid.
PREVALENCE AND EPIDEMIOLOGY —
Omphalocele and gastroschisis are the most common fetal abdominal wall defects in the United States, with prevalences of approximately 2 and 4 per 10,000 live births, respectively [5], consistent with the worldwide omphalocele prevalence of 2.6 per 10,000 births [6]. The prevalence of gastroschisis appears to be increasing at a faster rate than that of omphalocele [7].
The occurrence of omphalocele appears to be more common in offspring of females at the extremes of reproductive age [8,9]. In those <20 or >40 years of age, the odds of omphalocele in offspring are more than doubled compared with the general obstetric population (<age 20: odds ratio (OR) 2.45, 95% CI 1.22-4.86, >age 40: OR 8.76, 95% CI 4.02-19.32) [8]. In the United States, the prevalence is slightly higher in Black gravidas than White gravidas (1.91 versus 1.47 per 10,000 live births) [10]; this association is not believed to be genetic.
Modest associations between occurrence of omphalocele in offspring and maternal obesity and in utero exposure to selective serotonin reuptake inhibitor (SSRI) or methimazole have also been reported in some studies, while others have found no association [11-14]. Omphalocele has also been associated with male sex and multiple births [9]. There also appears to be a modest association with maternal alcohol consumption [15].
PRENATAL (FETAL) DIAGNOSIS
Potential benefits — Prenatal diagnosis of an omphalocele can increase the chance of identifying some syndromes before birth, thus providing time for parents to learn about and adjust to the abnormality; prepare for the needs of their offspring; and make arrangements to transfer to a center with prenatal, delivery, and/or neonatal care commensurate with maternal and/or neonatal needs. It also allows parents the option of terminating the pregnancy.
Presentation — Omphalocele is typically diagnosed as part of an obstetric ultrasound examination performed for a standard indication (eg, fetal anatomic survey, pregnancy dating, assessment of nuchal translucency for Down syndrome screening). Over 90 percent of cases are diagnosed prenatally [16].
Prenatal diagnosis of a non-liver-containing omphalocele can be made reliably after 12 weeks of gestation. Before 12 weeks, a small omphalocele can be difficult to differentiate from physiologic midgut herniation.
Prenatal diagnosis of liver-containing omphalocele can be made by transvaginal sonography as early as 9 to 10 weeks of gestation if a homogenous mass measuring greater than 5 to 10 mm in diameter suggestive of liver is imaged within the area of physiologic midgut herniation [17-22]. The sonographic diagnosis of a liver-containing omphalocele can be made before 12 weeks because herniated liver is never a normal developmental finding.
Findings on ultrasound
Diagnostic findings — An omphalocele appears as a midline abdominal wall defect of variable size in the area of the umbilicus, covered by a membranous sac containing abdominal contents, typically bowel (peristalsis can be observed) but often liver and occasionally stomach or bladder. The sac and/or abdomen may contain ascites. The cord inserts into the apex of the sac.
Eighty percent of omphaloceles contain part of the liver, which is documented by color Doppler images of the hepatic vessels or ductus venosus in the sac. The location of the liver inside or outside the sac is important, in part because small non-liver-containing omphaloceles are commonly associated with a fetal aneuploidy, while the larger liver-containing omphaloceles are usually associated with euploid fetuses [23-25]. (See 'Associated findings' below.)
The term “small” omphalocele has been used to describe an omphalocele <5 cm that may contain a few loops of intestines. The term "giant omphalocele" has been used to describe omphaloceles that contain most (>50 to 75 percent) of the liver or have a very large size (absolute size typically ≥5 cm or large size relative to the fetal abdomen [omphalocele cross-sectional area >50 percent of that of the fetal torso]) [26-28]. However, "small" and "large" are variably defined.
Diagnostic images:
●Ultrasound of normal umbilical cord insertion without and with color Doppler (image 2 and image 3)
●Ultrasound of omphalocele at 12 weeks of gestation (image 4)
●Ultrasound of omphalocele (containing liver) at 28 weeks of gestation (image 5)
●Three-dimensional ultrasound of omphalocele at 15 weeks of gestation (image 6)
Associated findings
Structural anomalies — Associated structural anomalies are common, occurring in 35 to 80 percent of cases [29-34]. The most common anomalies are gastrointestinal abnormalities (eg, malrotation, intestinal or anal atresia), cardiac anomalies (eg, ventricular septal defect, tetralogy of Fallot, dextrocardia), genitourinary anomalies (eg, agenesis of kidney or bladder, polycystic kidney, hydronephrosis, ureteral abnormalities), orofacial clefts, neural tube defects, and diaphragmatic defects [9,17,18,33,35-38].
Chromosomal abnormalities — Risk factors for chromosomal abnormalities include:
●Intracorporeal liver – When the sac contains only small intestine, there is a high frequency (>60 percent) of fetal aneuploidy, particularly trisomy 18 or 13 [23,25,39-41]. In one series of 250 fetuses with an omphalocele and an abnormal karyotype, the abnormalities included trisomy 18 (63 percent), trisomy 13 (17 percent), trisomy 21 (4 percent), Turner syndrome (6 percent), triploidy (5 percent), and rare chromosomal deletions (5 percent) [41].
●Associated structural anomalies – When associated anomalies are seen, the risk of chromosomal abnormalities is higher than in isolated omphalocele [26,31,34].
By comparison, fetuses with isolated omphalocele containing extracorporeal liver are often euploid (90 percent in some studies) [23,24], but not invariably [42].
Polyhydramnios — Polyhydramnios may occur after 20 weeks of gestation. It was observed in over one-third of cases in one series [43].
Fetal growth restriction — Fetal growth restriction is common in pregnancies complicated by an omphalocele, particularly with associated abnormalities [44-46]. (See 'Prenatal care' below.)
Syndromic etiologies — Omphalocele has been associated with several syndromes (table 1), which can be categorized by the location of the midline abdominal wall defect in the upper, middle, or lower abdomen (table 2) [47-53]. In one series of nearly 1500 newborns with omphalocele, the four most common genetic disorders identified were Beckwith-Wiedemann syndrome (BWS; 6 percent), trisomy 13 (3 percent), trisomy 18 (2 percent), and trisomy 21 (1 percent) [30].
The incidence of BWS is particularly high in fetuses with isolated omphalocele. In a single center series in which testing was consistently offered after exclusion of aneuploidy, BWS was diagnosed in 6 out of 16 (37.5 percent) fetuses with isolated and 1 out of 20 (5 percent) fetuses with nonisolated omphaloceles [54]. The genetics, clinical manifestations, and diagnosis of BWS are reviewed in detail separately. (See "Beckwith-Wiedemann syndrome".)
Differential diagnosis
●Gastroschisis – Gastroschisis is the major disorder to consider in differential diagnosis of omphalocele. In contrast to omphalocele, which is midline and in the area of the umbilicus, the abdominal wall defect in most cases of gastroschisis is to the right side of a normal appearing umbilical cord insertion site. An omphalocele typically has a membranous sac that contains bowel, whereas gastroschisis is characterized by loops of bowel free floating in amniotic fluid. However, omphalocele membranes occasionally rupture in utero, particularly in giant omphaloceles, allowing bowel to float freely. In such cases, an extracorporeal liver and/or a midline umbilical defect site suggest an omphalocele, while an intracorporeal liver and a paraumbilical defect suggest gastroschisis. Omphalocele rupture has been observed in 7 to 15 percent of cases at birth [55]. (See "Gastroschisis".)
●Umbilical cord hernia – In an umbilical cord hernia, the umbilical cord inserts normally into the umbilical ring, which is surrounded by intact skin and is typically <2 cm in diameter, whereas in an omphalocele, the cord inserts into a membranous sac that covers a large abdominal wall defect occupying the area of the umbilical ring [56-58]. Like an omphalocele, the hernia is at the base of the umbilical cord. Also like an omphalocele, umbilical cord hernias can contain bowel, but in contrast to omphaloceles, they are not associated with an increased risk for anomalies or genetic syndromes. Pathogenesis is also probably different. Omphalocele is either a rotational abnormality or a primary failure of the four body folds to form a normal midabdominal wall, whereas in umbilical cord hernia, the body folds develop normally, but physiologic midgut herniation may persist and result in a simple hernia.
●Other major abdominal wall defects – Other abdominal wall defects in differential diagnosis, such as ectopia cordis, limb-body wall complex, cloacal exstrophy, Pentalogy of Cantrell, and urachal cyst, are rare (prevalence of each less than 1 in 100,000 births). They can be differentiated by their location (upper, middle, or lower abdomen), cord insertion, and associated abnormalities (table 2). Omphalocele and body stalk defects are both connected to the cord, but body stalk anomaly is also associated with scoliosis and a short umbilical cord. Ectopia cordis (and the Pentalogy of Cantrell) has at least a portion of the heart outside of the body cavity and is the classic upper midline abdominal wall defect. Bladder exstrophy develops below the cord insertion and is the classic lower midline abdominal wall defect.
Amniotic band sequence (ABS) can also result in abdominal wall disruption. Other structures beyond the abdominal wall are often involved in ABS, such as the cranium (eg, anencephaly, encephalocele), spine (eg, neural tube defect), and limbs (eg, amputations). (See "Amniotic band sequence".)
Associated maternal findings — The gravida is asymptomatic. Maternal serum alpha-fetoprotein concentration may be elevated if performed as part of screening for neural tube defects [59-61].
POSTDIAGNOSTIC FETAL EVALUATION —
After an omphalocele is diagnosed, further evaluation of the fetus includes:
●Microarray – Chromosomal microarray analysis should be offered if an omphalocele or related body wall defects are identified prenatally because of the increased risk of aneuploidy, especially in cases with an intracorporeal liver or additional anomalies in other organ systems. (See "Prenatal genetic evaluation of the fetus with anomalies or soft markers".)
●Echocardiogram – We suggest performing a fetal echocardiogram, given the increased incidence of cardiac abnormalities (see "Congenital heart disease: Prenatal screening, diagnosis, and management", section on 'Indications for echocardiography'). Magnetic resonance imaging (MRI) is utilized on a case-by-case basis when it can provide additional information needed for pregnancy management.
●Testing for Beckwith-Wiedemann syndrome (BWS), if microarray is normal – Given the high risk of BWS in euploid fetuses with omphalocele, it is reasonable to offer testing for BWS, but this testing is complex and should be discussed with a geneticist [62]. We offer testing to all patients with fetal omphalocele (isolated or nonisolated) after confirmation of euploidy, recognizing that the risk for BWS is higher in isolated cases but still increased above baseline in nonisolated cases [54]. Methylation-sensitive multiplex ligation probe analysis (MS-MLPA) is the most robust method available for detecting the majority of epigenetic and genetic variations at 11p15 associated with this syndrome. These abnormalities include microdeletions, microduplications, alterations in gene dosage, DNA methylation at two imprinting centers, and uniparental disomy. (See "Beckwith-Wiedemann syndrome".)
●Exome sequencing, if microarray and BWS testing are normal – If microarray and BWS testing are normal, fetal exome sequencing is an option, given that it increases the diagnostic yield in structurally abnormal fetuses by approximately 8 to 10 percent after normal microarray results [63]. Few data are available in patients with omphalocele [64,65]. In one study, three patients with non-isolated omphalocele and normal microarray accepted exome sequencing and one had a pathogenic variant [64]. This fetus had an omphalocele, cystic hygroma, spinal malformation, and short limbs and its mother had two similarly affected previous pregnancies.
PRENATAL CARE
Parental counseling — After the prenatal diagnosis of omphalocele is established, parents can benefit from the additional expertise and perspective provided by a team of maternal-fetal medicine specialists, neonatologists, pediatric surgeons, and genetic counselors working in collaboration.
Key issues for discussion include:
●In utero therapeutic interventions are not available.
●Although the omphalocele may appear to be an isolated anomaly prenatally, a substantial proportion of these fetuses will have associated abnormalities identified after birth (range 11 to 39 percent [62,66,67]). In one study of 87 fetuses with apparently isolated omphalocele and normal or untested karyotype, 61 percent were confirmed to have an isolated abnormality postnatally, while 13 percent had a cardiac abnormality, 11 percent had other abnormalities, 9 percent had Beckwith-Wiedemann syndrome (BWS), and 5 percent had another diagnosis (eg, gastroschisis, cloaca) postnatally [67].
●Neonatal morbidity and mortality rates directly correlate with the presence and severity of associated anatomic and chromosomal anomalies [31,68-70]. Omphalocele associated with pulmonary hypoplasia from Pentalogy of Cantrell, trisomy 13 or 18, or triploidy generally carries a dismal prognosis. (See 'Outcome' below.)
●If the parents choose to terminate the pregnancy, evaluation of the products of conception is recommended to confirm/determine the etiology of the omphalocele if unclear prenatally, as identifying a syndrome can be helpful in determining recurrence risk in future pregnancies.
●The postnatal course can be difficult to predict. A primary repair may be possible, or repair can be a long and difficult process, involving multiple reconstructive procedures [71]. Poorer prognostic factors include an extracorporeal liver [44,72], large absolute or relative defect size (eg, ratio of omphalocele circumference/abdominal circumference [AC], ratio of defect diameter/widest diameter of the abdomen parallel to the defect), and the presence and type of additional congenital anomalies [73].
Fetal follow-up
●Serial sonography to monitor fetal growth – In addition to routine prenatal care, we follow most of these pregnancies with serial ultrasound examinations every three to four weeks to evaluate fetal growth. Fetal growth restriction is common and predictive of an increased risk of adverse neonatal outcome [44].
The most commonly used formulas for estimating fetal weight rely heavily on the measurement of abdominal circumference (AC) and tend to underestimate fetal weight because the omphalocele contains abdominal contents that would otherwise enlarge the AC. Therefore, when AC is small and discordant with estimated gestational age, we look closely at the size and growth velocity of other biometric parameters (eg, femur length, biparietal diameter) and amniotic fluid volume. If these findings are in the low normal range or are consistent with growth restriction, we perform umbilical artery Doppler velocimetry. (See "Fetal growth restriction: Evaluation".)
One group developed a specific formula for estimating fetal weight in fetuses with abdominal wall defects [74]. It uses the biparietal diameter, occipitofrontal diameter, and femur length measurements, thus it may estimate fetal weight in these fetuses more accurately than formulas using AC [74-76]. However, it is not widely used and few validating data are available.
In patients with BWS who undergo serial ultrasound examinations after identification of omphalocele, other signs of BWS, such as fetal overgrowth, macroglossia, visceromegaly, and retrognathia, when present, are typically detected after 20 weeks of gestation [77].
●Nonstress test/biophysical profile – When growth is appropriate and amniotic fluid volume is normal, we begin weekly nonstress testing or biophysical profile monitoring at 32 weeks of gestation to assess fetal well-being, as fetuses with omphalocele appear to be at increased risk of late fetal death [78,79]. We increase the frequency of fetal surveillance in pregnancies with additional complications, such as growth restriction, oligohydramnios, or cases of nonisolated omphalocele. (See "Fetal growth restriction: Evaluation" and "Oligohydramnios: Etiology, diagnosis, and management in singleton gestations".)
Location, timing, and route of delivery
●Location – Planning for delivery at a tertiary care center, as opposed to transporting a critically ill infant, provides optimal outcome for the newborn [29]. Increased morbidity in "out-born" neonates may be related to factors such as temperature and hydration status, initial care of the anomaly, and vascular compromise of prolapsed gut during prolonged transportation [80].
●Timing – In the absence of standard indications for early delivery, expectant management is reasonable until spontaneous labor or at least 39+0 weeks of gestation. Preterm birth offers no advantage to affected neonates and is associated with increased morbidity and mortality. In one series of prenatally diagnosed isolated omphalocele, the only neonatal deaths occurred because of complications of prematurity [62]. As in other pregnancies, nonreassuring fetal testing and/or cessation of fetal growth at or near term is an indication for early delivery.
●Route – In most patients with omphalocele, we suggest a trial of labor and vaginal birth in the absence of standard indications for cesarean birth, as there is no strong evidence that cesarean birth improves outcome [29,55,81-83]. No randomized trials evaluating the optimum route of delivery for these pregnancies have been performed. Our approach is based on a meta-analysis of 15 observational studies that found cesarean birth was associated with an increased likelihood of primary repair (pooled relative risk [RR] 1.22, 95% CI 0.99-1.51) but no clear improvement in rates of neonatal sepsis (pooled RR 0.70, 95% CI 0.30-1.62) or pediatric mortality (pooled RR 1.14, 95% CI 0.59-2.21) [84]. Route of delivery was also not a factor in time until enteral feeding or length of hospital stay.
We suggest cesarean birth for fetuses with giant omphaloceles (defined as an omphalocele containing >75 percent of the liver or a defect greater than 5 cm) in an attempt to avoid dystocia, rupture, infection, and hemorrhage [85], but we acknowledge that visceral trauma has also been reported after cesarean birth [82]. If a scheduled cesarean birth is performed, it should be at ≥39+0 weeks of gestation in the absence of standard indications for earlier delivery.
Outcome — A study using a prospectively collected database including almost 1500 infants with omphalocele discharged from 348 neonatal intensive care units in North America from 1997 to 2012 reported the following outcomes [30]. No information was available on the frequency of pregnancy termination or the characteristics of fetuses who were aborted, which likely biases the findings.
●60 percent of births occurred at term and 28 percent occurred between 33 and 36 weeks. The increased frequency of preterm birth was related, in part, to preterm prelabor rupture of membranes.
●35 percent of cases were associated with at least one other anomaly.
●82 percent of live births survived to hospital discharge; the median length of hospitalization after birth in this group was 17 days.
●9 percent had pulmonary hypertension, and one-half of these newborns received pulmonary vasodilating drugs.
The risk of infant death is as high as 45 percent in infants with pulmonary hypertension. The incidence of pulmonary hypertension appears to correlate with the size of the defect; it has been reported in 37 percent of infants with giant omphalocele, which can cause pulmonary hypoplasia [86].
Some infants require support with extracorporeal membrane oxygenation (ECMO). In such cases, the mortality rate is substantially higher than in those not requiring ECMO, and was 82 percent in one series [87].
APPROACH TO THE NEONATE
Delivery room — The key factor at birth is to avoid clamping the omphalocele sac when the umbilical cord is clamped and cut. (In umbilical cord hernias, it is important to avoid clamping the proximal part of the umbilical cord, which may contain occult herniated bowel.)
The immediate care of the newborn with omphalocele involves [29,88]:
●Wrapping the bowel with a sterile, saline-soaked gauze and impervious dressing to preserve heat and minimize insensible fluid loss
●Insertion of an orogastric tube to decompress the stomach
●Stabilizing the airway to ensure adequate ventilation
●Establishing peripheral intravenous access
●Positioning left-side down right-side up if low blood pressure, tachycardia, or dusky bowel appearance suggesting vascular compromise
One approach is to place gauze dressings soaked in warm sterile saline and cover the dressing with clear plastic wrap; some use a plastic bag that encloses the infant up to the chest. Excessively wet and circumferential dressings should be avoided because they can macerate the omphalocele sac and cause the newborn's temperature to drop [88]. Circumferential abdominal wall wraps also should be avoided, as they have the potential to compromise blood flow.
Intravenous fluids and broad spectrum antibiotics are administered [88]. Cardiorespiratory and fluid status should be monitored closely and a thorough physical examination performed to identify additional malformations. The neonate should be maintained in a thermoneutral environment.
Synopsis of surgical management — The priority for abdominal wall repair is preservation of intestinal blood flow. In all cases, the size of the abdominal wall defect must be balanced with right of domain (ie, anteroposterior depth of abdominal cavity). In general, small defects (2 to 3 cm) can be repaired in the first 24 to 72 hours of life by primary closure of both fascia and skin. The remaining spectrum of defects usually involves some type of silo in the first 24 hours of life and delayed closure. The silo can be reduced gradually over three to seven days in the intensive care unit, after which the infant is returned to the operating room for final closure of the abdominal wall [88,89]. Reducing a large defect or one that contains an anatomically kinked liver can be done with Doppler ultrasound guidance to ensure the vena cava and hepatic outflow are not compromised during the silo reduction. Giant omphaloceles (ie, containing >75 percent of the liver or defect greater than 5 cm) may be managed by a combination of silo, acellular dermal patch, and skin graft or by promoting formation of an amniotic sac eschar by application of a sclerosing solution (topical povidone-iodine), with delayed hernia repair.
After omphalocele reduction, the neonate may require prolonged mechanical ventilation because of respiratory difficulties and caval compression. Postoperative increase in intra-abdominal pressure required to restore intestinal right of domain must be carefully monitored through urine output, pulse rate, and blood pressure [29,85]. Infants with very large omphaloceles containing most of the liver may require multiple reconstructive procedures and have the potential for long-term morbidity [85]. Nutritional status, associated anomalies, and pulmonary hypoplasia all play major roles in determining whether the child will have a good long-term outcome [90].
RISK OF RECURRENCE IN FUTURE PREGNANCY —
The recurrence risk is dependent on the underlying cause.
●Most cases of omphalocele are sporadic. For isolated omphalocele with a normal fetal karyotype, the recurrence risk is less than 1 percent [91].
●For omphalocele with a trisomic karyotype, the recurrence risk is 1 percent but increases if a parental balanced translocation is detected. The risk depends on the specific translocation.
●For omphalocele with Beckwith-Wiedemann syndrome (BWS), microarray should be performed to look for duplications or abnormalities of chromosome 11p15. Familial cases of BWS can be autosomal dominant and have a 50 percent recurrence risk. (See "Beckwith-Wiedemann syndrome", section on 'Genetics and pathogenesis' and "Beckwith-Wiedemann syndrome", section on 'Genetic counseling' and "Beckwith-Wiedemann syndrome".)
SUMMARY AND RECOMMENDATIONS
●Definition and diagnosis – An omphalocele is a type of abdominal wall defect (picture 1). The prenatal diagnosis is based on ultrasound examination and made in a fetus with a midline abdominal wall defect of variable size in the area of the umbilicus, covered by a membranous sac, and containing herniated abdominal contents (typically bowel, but often liver, and occasionally stomach or bladder) (image 5 and image 6). The cord inserts into the apex of the sac. Ascites may be seen in the sac or the abdomen. (See 'Findings on ultrasound' above.)
A “giant” omphalocele can be defined as an omphalocele containing >75 percent of the liver or a defect greater than 5 cm. (See 'Findings on ultrasound' above.)
Prenatal ultrasound examination can detect almost all cases of omphalocele and define associated anomalies, which can occur in any organ system and can be syndromic. (See 'Associated findings' above and 'Syndromic etiologies' above.)
●Differential diagnosis – Gastroschisis is the major disorder to consider in differential diagnosis. It can be differentiated from omphalocele by its absence of a membranous sac and its paraumbilical (rather than umbilical) cord insertion site (image 7 and image 8). (See 'Differential diagnosis' above.)
●Postdiagnostic evaluation – Postdiagnostic evaluation of fetuses with omphalocele includes (see 'Postdiagnostic fetal evaluation' above):
•Fetal chromosomal microarray, because of the increased risk of aneuploidy. An isolated omphalocele containing liver is usually associated with fetal euploidy, whereas associated anomalies and an intracorporeal liver are commonly associated with aneuploidy.
•Echocardiogram.
•Testing for Beckwith-Wiedemann syndrome in euploid fetuses.
•Exomic sequencing for euploid fetuses with negative test results for Beckwith-Wiedemann syndrome.
●Pregnancy management
•Fetal surveillance – When growth is appropriate and amniotic fluid volume is normal, we begin weekly nonstress testing or biophysical profile monitoring at 32 weeks of gestation to assess fetal well-being. We increase the frequency of fetal surveillance in pregnancies with additional complications, such as growth restriction, oligohydramnios, or nonisolated omphalocele. (See 'Fetal follow-up' above.)
•Timing of birth – In the absence of standard indications for early delivery, expectant management is reasonable until spontaneous labor or at least 39 weeks of gestation. Preterm birth offers no advantage to affected neonates and is associated with increased morbidity and mortality. (See 'Location, timing, and route of delivery' above.)
•Route of birth – For most patients with fetuses with omphalocele, we suggest a trial of labor (Grade 2C). We perform a cesarean birth in selected cases, including fetuses with giant omphalocele. (See 'Location, timing, and route of delivery' above.)
●Care of the newborn – Ideally, delivery should occur at a tertiary care center with the appropriate level of neonatal medical and surgical care. In the delivery room, neonatal management involves covering the defect with gauze dressings soaked in thermally neutral sterile saline, covering the dressing with clear plastic wrap, inserting an orogastric tube to decompress the stomach, stabilizing the airway to ensure adequate ventilation, and establishing peripheral intravenous access. (See 'Approach to the neonate' above.)
●Outcome – Overall survival of live born infants is approximately 90 percent. This high rate reflects the ability to diagnose abdominal wall defects prenatally and the decision of many families to proceed with termination of pregnancy when the defect is severe or multiple associated anomalies are present. (See 'Parental counseling' above.)
●Recurrence risk – Most cases of omphalocele are sporadic. Recurrence risk depends on the cause. (See 'Risk of recurrence in future pregnancy' above.)
