The role of antepartum surveillance in the management of gastroschisis

Risk of Stillbirth for Fetuses With Specific Birth Defects

OBJECTIVE

To estimate the risk of stillbirth (fetal death at 20 weeks of gestation or more) associated with specific birth defects.

METHODS

We identified a population-based retrospective cohort of neonates and fetuses with selected major birth defects and without known or strongly suspected chromosomal or single-gene disorders from active birth defects surveillance programs in nine states. Abstracted medical records were reviewed by clinical geneticists to confirm and classify all birth defects and birth defect patterns. We estimated risks of stillbirth specific to birth defects among pregnancies overall and among those with isolated birth defects; potential bias owing to elective termination was quantified.

RESULTS

Of 19,170 eligible neonates and fetuses with birth defects, 17,224 were liveborn, 852 stillborn, and 672 electively terminated. Overall, stillbirth risks ranged from 11 per 1,000 fetuses with bladder exstrophy (95% CI 0-57) to 490 per 1,000 fetuses with limb-body-wall complex (95% CI 368-623). Among those with isolated birth defects not affecting major vital organs, elevated risks (per 1,000 fetuses) were observed for cleft lip with cleft palate (10; 95% CI 7-15), transverse limb deficiencies (26; 95% CI 16-39), longitudinal limb deficiencies (11; 95% CI 3-28), and limb defects due to amniotic bands (110; 95% CI 68-171). Quantified bias analysis suggests that failure to account for terminations may lead to up to fourfold underestimation of the observed risks of stillbirth for sacral agenesis (13/1,000; 95% CI 2-47), isolated spina bifida (24/1,000; 95% CI 17-34), and holoprosencephaly (30/1,000; 95% CI 10-68).

CONCLUSION

Birth defect-specific stillbirth risk was high compared with the U.S. stillbirth risk (6/1,000 fetuses), even for isolated cases of oral clefts and limb defects; elective termination may appreciably bias some estimates. These data can inform clinical care and counseling after prenatal diagnosis.

Population-based birth defects data in the United States, 2012-2016: A focus on abdominal wall defects

BACKGROUND/OBJECTIVES

In this report, the National Birth Defects Prevention Network (NBDPN) examines and compares gastroschisis and omphalocele for a recent 5-year birth cohort using data from 30 population-based birth defect surveillance programs in the United States.

METHODS

As a special call for data for the 2019 NBDPN Annual Report, state programs reported expanded data on gastroschisis and omphalocele for birth years 2012-2016. We estimated the overall prevalence (per 10,000 live births) and 95% confidence intervals (CI) for each defect as well as by maternal race/ethnicity, maternal age, infant sex, and case ascertainment methodology utilized by the program (active vs. passive). We also compared distribution of cases by maternal and infant factors and presence/absence of other birth defects.

RESULTS

The overall prevalence estimates (per 10,000 live births) were 4.3 (95% CI: 4.1-4.4) for gastroschisis and 2.1 (95% CI: 2.0-2.2) for omphalocele. Gastroschisis was more frequent among young mothers (<25 years) and omphalocele more common among older mothers (>40 years). Mothers of infants with gastroschisis were more likely to be underweight/normal weight prior to pregnancy and mothers of infants with omphalocele more likely to be overweight/obese. Omphalocele was twice as likely as gastroschisis to co-occur with other birth defects.

CONCLUSIONS

This report highlights important differences between gastroschisis and omphalocele. These differences indicate the importance of distinguishing between these defects in epidemiologic assessments. The report also provides additional data on co-occurrence of gastroschisis and omphalocele with other birth defects. This information can provide a basis for future research to better understand these defects.

National Practice Patterns for Prenatal Monitoring in Gastroschisis: Gastroschisis Outcomes of Delivery (GOOD) Provider Survey

BACKGROUND

Gastroschisis is an abdominal wall defect with increasing incidence. Given the lack of surveillance guidelines among maternal-fetal medicine (MFM) specialists, this study describes current practices in gastroschisis management.

MATERIALS AND METHODS

An online survey was administered to MFM specialists from institutions affiliated with the North American Fetal Therapy Network (NAFTNet). Questions focused on surveillance timing, testing, findings that changed clinical management, and delivery plan.

RESULTS

Responses were obtained from 29/29 (100%) NAFTNet centers, comprising 143/371 (39%) providers. The majority had a regimen for antenatal surveillance in patients with stable gastroschisis (94%; 134/141). Antenatal testing began at 32 weeks for 68% (89/131) of MFM specialists. The nonstress test (55%; 72/129), biophysical profile (50%; 63/126), and amniotic fluid index (64%; 84/131) were used weekly. Estimated fetal weight (EFW) was performed monthly by 79% (103/131) of providers. At 28 weeks, abnormal EFW (77%; 97/126) and Doppler ultrasound (78%; 99/127) most frequently altered management. In stable gastroschisis, 43% (60/140) of providers delivered at 37 weeks, and 29% (40/ 140) at 39 weeks.

DISCUSSION

Gastroschisis management differs among NAFTNet centers, although the majority initiate surveillance at 32 weeks. Timing of delivery still requires consensus. Prospective studies are necessary to further optimize practice guidelines and patient care.

Metaanalysis of the prevalence of intrauterine fetal death in gastroschisis

OBJECTIVE

The objective of this study was to review the medical literature that has reported the risk for intrauterine fetal death (IUFD) in pregnancies with gastroschisis.

STUDY DESIGN

We systematically searched the literature to identify all published studies of IUFD and gastroschisis through June 2011 that were archived in MEDLINE, PubMed, or referenced in published manuscripts. The MESH terms gastroschisis or abdominal wall defect were used.

RESULTS

Fifty-four articles were included in the metaanalysis. There were 3276 pregnancies in the study and a pooled prevalence of IUFD of 4.48 per 100. Those articles that included gestational age of IUFD had a pooled prevalence of IUFD of 1.28 per 100 births at ≥36 weeks' gestation. The prevalence did not appear to increase at >35 weeks' gestation.

CONCLUSION

The overall incidence of IUFD in gastroschisis is much lower than previously reported. The largest risk of IUFD occurs before routine and elective early delivery would be acceptable. Risk for IUFD should not be the primary indication for routine elective preterm delivery in pregnancies that are affected by gastroschisis.

Fetal and neonatal outcome in patients with anterior abdominal wall defects (gastroschisis and omphalocele)

Fetuses with gastroschisis and omphalocele frequently show intrauterine growth restriction (IUGR). The aim of our study was to evaluate the intrauterine course of IUGR and the neonatal outcome in a large patient collective. We retrospectively included all euploid fetuses with gastroschisis and omphalocele between 2001 and 2009 in a single tertiary center. Patients' characteristics, serial ultrasound examinations and neonatal outcomes were evaluated. From 39 fetuses (28 gastroschisis, 11 omphalocele) 61.5% had IUGR <5th percentile and 15.4% had IUGR<10th percentile. The rate of IUGR did not differ significantly between the two groups during pregnancy. Newborns with gastroschisis showed an average weight of 2386 g, and those with omphalocele showed an average weight of 3148 g (P<0.001). Nevertheless, newborns with omphalocele were more frequently eutrophic than those with gastroschisis (88.8% vs. 52.2%, P=0.079). On average, only one surgical intervention was necessary for the definitive repair of the defect (65.5% of the newborns). Children with gastroschisis remained hospitalized nearly twice as long as children with an omphalocele (38 vs. 20 days). IUGR rates during pregnancy did not differ significantly between fetuses with gastroschisis and omphalocele although patients with defects of omphalocele were more frequently eutrophic at birth. Most newborns needed only one operation for definitive surgical treatment. The mean hospitalization time after this intervention was 4 weeks.

Echogenic bowel on second-trimester ultrasonography: evaluating the risk of adverse pregnancy outcome

OBJECTIVE

To estimate if echogenic bowel diagnosed on second-trimester ultrasonography has an independent risk association with intrauterine growth restriction (IUGR) and intrauterine fetal demise.

METHODS

This is a retrospective cohort study of all patients with singleton gestations who presented to our institution for second-trimester ultrasonography between 1990 and 2008. Study groups were defined by the presence or absence of echogenic bowel. Primary outcomes were IUGR, defined as birth weight less than the 10th percentile for gestational age and intrauterine fetal demise at 20 weeks or more of gestation. Univariable and multivariable logistic regression analyses were used to estimate the risk of intrauterine fetal demise and IUGR in fetuses with echogenic bowel. Analyses were repeated after excluding cases of aneuploidy, cytomegalovirus (CMV) infection, other major congenital anomalies, and abnormal second-trimester serum screening results.

RESULTS

Of 64,048 patients, the incidence of echogenic bowel was 0.4%. Of these, echogenic bowel was an isolated finding in 188 (72.3%) cases. There were 579 (0.9%) cases of intrauterine fetal demise and 8,173 (12.8%) cases of IUGR in the entire cohort. After excluding cases of aneuploidy and CMV infection, the incidence of intrauterine fetal demise was 7.3% in the echogenic bowel group compared with 0.9% in the nonechogenic bowel group, translating to an absolute risk increase of 6.4%. The incidence of IUGR in the echogenic bowel group was 19.5% compared with 12.9% in the nonechogenic bowel group (absolute risk increase, 6.6%). After controlling for potential confounders, echogenic bowel was significantly associated with both intrauterine fetal demise (adjusted odds ratio [OR] 9.6, 95% confidence interval [CI] 5.8-15.9) and IUGR (adjusted OR 2.1, 95% CI 1.5-2.9). This risk association remained significant even when evaluating echogenic bowel as an isolated sonographic finding.

CONCLUSION

The presence of echogenic bowel on ultrasonography is independently associated with an increased risk for both IUGR and intrauterine fetal demise. Serial growth assessment and antenatal testing may be warranted in these patients.

Ultrasound prediction of growth abnormalities in fetuses with gastroschisis

OBJECTIVE

We seek to determine whether (1) mean abdominal circumference (AC) of fetuses with gastroschisis is smaller than published normative values, (2) diagnosis of AC ≤ 2.5th percentile is supported by postnatal diagnosis of small-for-gestational age (SGA) and (3) adverse neonatal outcomes are more common in fetuses affected by gastroschisis with a sonographically measured small AC.

METHODS

Retrospective review of pregnancies complicated with gastroschisis between 2000 and 2008. Patient demographics, method of closure, length of stay, use of ventilator support and gastrointestinal complications were compared.

RESULTS

Seventy-four fetuses were identified with 368 ultrasound observations. Mean AC of fetuses with gastroschisis fell between the 2.5th and 50th percentile for gestational age. Thirty patients had AC measurements ≤ 2.5th of which 50% were SGA at delivery. Eleven of the 74 fetuses were diagnosed with intrauterine growth restriction (IUGR) and all were SGA. Birth weight was lower in those with a small AC (2104 g vs. 2665 g, p<0.001). There were no other differences in outcomes.

CONCLUSION

AC values fell within the normal range of normative curves. Fifty percent of fetuses with small AC were SGA at birth. Neonatal outcomes in patients with small AC are similar to those with a normal AC.

Gastroschisis: what is the average gestational age of spontaneous delivery?

BACKGROUND/PURPOSE

To consolidate what is known about pregnancies complicated by fetal gastroschisis through analysis of one of the largest series yet reported and to define the average gestational age of spontaneous delivery.

METHODS

From 1980 to 2001, 159 pregnancies complicated by fetal gastroschisis were identified at a tertiary care center. Gestational age at delivery, birth weight, preterm delivery rate, and maternal age were compared to the 2001 general population statistics. Patients with pregnancies complicated by gastroschisis who went into spontaneous labor (n = 86) were subdivided into 2 groups based on gestational age (< 37 weeks and > or = 37 weeks). Operative delivery rates for nonreassuring fetal status and Apgar scores were assessed.

RESULTS

Gastroschisis occurred more often in younger mothers (< 21 years) (42% vs 7.3%), was more frequently associated with preterm labor and delivery (28% vs 6%), and was associated with more low-birth-weight babies (36% vs 10%). The mean gestational age at spontaneous labor was 36.6 weeks. In those patients who labored spontaneously, there were no significant differences in the operative delivery rates for fetal distress; however, there was a trend to lower Apgar scores in babies born at 37 weeks or more.

CONCLUSION

Our data provide a framework for further studies to determine the optimal timing and mode of delivery for fetuses with gastroschisis.

Gastroschisis: Growth Patterns and a Proposed Prenatal Surveillance Protocol

OBJECTIVE

To assess intrauterine growth for fetuses with gastroschisis using retrospective serial ultrasound assessment from fetuses diagnosed prenatally with gastroschisis. The growth assessment could be available as a prospective tool to direct an antepartum fetal surveillance protocol.

METHODS

This is a retrospective review of all cases of gastroschisis evaluated prenatally at a single institution between February 1996 and March 2002. Charts were reviewed for serial ultrasound assessment, gestational age at delivery, mode of delivery, and birth weight. Growth assessment was determined for abdominal circumference, biparietal diameter, head circumference, femur length, and estimated fetal weight (IRB No. 2002-1-2648).

RESULTS

Forty patients had delivered by March 2002. One hundred and two ultrasound reports were reviewed. Gastroschisis growth curves showed that the 50th percentile was shifted to the right when compared to normal growth curves for abdominal circumference, biparietal diameter, head circumference, and femur length. The average birth weight was 2,359 g. Compared with a standard population, 44% (16/36) were below the 5th percentile, 61% (22/36) were below the 10th percentile, and 95% (34/36) were below the 50th percentile for gestational age. The average gestational age at delivery was 36.3 weeks. Mothers were nulliparous in 78%, with a mean age of 21.3 years.

CONCLUSIONS

(1) Fetuses with gastroschisis show a symmetric intrauterine growth restriction pattern consistent with early development of growth delay; (2) the 50th percentile biometry measurements for the gastroschisis population are shifted to the right on normal fetal growth curves; (3) the birth weight is at or below the 10th percentile in 61% of the newborns with gastroschisis, and (4) an antepartum surveillance protocol is proposed based on growth patterns of fetuses with gastroschisis.

Surveillance and outcome of fetuses with gastroschisis

OBJECTIVES

Infants with gastroschisis have a high survival rate. However, the rate (10-15%) of intrauterine fetal death (IUFD) is considerable, and the association with fetal distress is well known. The aim of this study was to describe the outcome of fetuses with a prenatal diagnosis of gastroschisis. The impact of correct prenatal diagnosis, surveillance and signs of complicating risk factors were evaluated.

METHODS

All fetuses with prenatally diagnosed gastroschisis at the National Center for Fetal Medicine from January 1988 to August 2002 were registered and prospectively evaluated with regular ultrasound examinations. From 34-36 completed gestational weeks the fetuses were monitored daily to every second day with cardiotocography (CTG).

RESULTS

Gastroschisis was diagnosed in 64 fetuses at a mean gestational age of 19 + 2 weeks. All had normal karyotype. Associated anomalies were found in four cases (6.3%). Three pregnancies (4.7%) were terminated, all for reasons other than gastroschisis. One fetus (1.6%) died in utero. Thirteen fetuses (22%) had abnormal CTG leading to subsequent Cesarean sections. Mean gestational age at delivery was 36 + 1 weeks. Mean birth weight was 2586 g. Thirteen infants (22%) were small for gestational age (SGA). In 15 cases (25%) meconium-stained amniotic fluid was found; 14 of these had abnormal CTG and/or were SGA. Small bowel atresia was found in four infants (6.7%). Four infants died postnatally at the age of 0-9 months.

CONCLUSIONS

CTG surveillance of fetuses with gastroschisis may improve the outcome through detection of fetal distress thereby reducing the risk of IUFD. Other clinical situations of importance that are associated with gastroschisis are described and discussed.

Prenatal management of gastroschisis: the place of the amnioexchange procedure

Gastroschisis is a malformation of the anterior abdominal wall that consists of a right paraumbilical defect with bowel loops bathed in the amniotic fluid. The survival rate is now greater than 90% and the prognosis relies mainly on morbidity attributable to bowel dysfunction. Recent research has examined gastrointestinal waste present in amniotic fluid that induces bowel toxicity and an inflammatory process. The amnioexchange procedure (changing the amniotic fluid regularly) involves a new therapeutic approach: reducing bowel injuries in the fetuses. This article shows that there is an inflammatory reaction in human gastroschisis and in the authors' model, and that the clinical and biological data plead for the practice of amnioexchange in human beings. A randomized, controlled study is now needed.

The influence of bowel atresia in gastroschisis on fetal growth, cardiotocograph abnormalities and amniotic fluid staining

OBJECTIVES

To investigate the relationship between intestinal atresia and fetal growth, intrapartum cardiotocograph abnormalities and staining of the amniotic fluid in gastroschisis pregnancies.

DESIGN

Observational study of 115 gastroschisis pregnancies conceived between 1980 and 1996.

SETTING

South West Region of England.

MAIN OUTCOME MEASURES

Birthweight, intrapartum cardiotocograph abnormality, staining of amniotic fluid and Apgar score.

RESULTS

There was no statistically significant difference between the Apgar scores or the frequency of amniotic fluid staining of gastroschisis cases with or without atresia. Patent bowel gastroschisis was associated significantly with more cardiotocograph abnormalities (61% vs 26%, P = 0.026) and reduced growth (P = 0.02), when compared with cases with intestinal atresia.

CONCLUSIONS

Bile vomiting may be an important cause of amniotic fluid staining. Bowel atresia protects against the increased incidence of cardiotocograph and growth abnormality found in cases of gastroschisis which may reflect their aetiology.