Factors associated with fetal demise in fetal echogenic bowel

The Role of Prenatal Ultrasound and Added Value of Post-Mortem Radiographic Imaging With X-Ray and CT in Suspected Fetal Skeletal Dysplasia

OBJECTIVE

This study aims to assess the diagnostic value of post-mortem radiographic imaging compared with prenatal ultrasound in suspected fetal skeletal dysplasias in a large Finnish cohort.

METHOD

Prenatal ultrasound findings and their association with post-mortem radiographic imaging were evaluated in a cohort of 36 fetuses with prenatally suspected skeletal dysplasia.

RESULTS

Prenatal ultrasound performed well in detecting skeletal dysplasias and severe forms of the disease. Additional radiographic imaging was performed post-mortem in 16/27 terminated pregnancies. Post-mortem X-ray and 3D-CT detected several features not seen with US. They were superior to US in identifying spinal and thoracic anomalies and performed better in discovering fractures and deformities of long bones. In addition, disease-specific findings became more accurate with X-ray/CT, especially in the group of true skeletal dysplasias (14/18, 77.8%). Post-mortem X-ray and CT increased phenotypic data and facilitated interpretation of genetic findings.

CONCLUSION

Post-mortem X-ray and CT offer additional information supporting the diagnostic process. Detailed phenotypic data are important in interpreting the results of genetic analyses and in assessing the recurrence risk in future pregnancies. Complementary imaging methods including post-mortem radiography are therefore recommended.

The Welsh study of mothers and babies: protocol for a population-based cohort study to investigate the clinical significance of defined ultrasound findings of uncertain significance

BACKGROUND

Improvement in ultrasound imaging has led to the identification of subtle non-structural markers during the 18 - 20 week fetal anomaly scan, such as echogenic bowel, mild cerebral ventriculomegaly, renal pelvicalyceal dilatation, and nuchal thickening. These markers are estimated to occur in between 0.6% and 4.3% of pregnancies. Their clinical significance, for pregnancy outcomes or childhood morbidity, is largely unknown. The aim of this study is to estimate the prevalence of seven markers in the general obstetric population and establish a cohort of children for longer terms follow-up to assess the clinical significance of these markers.

METHODS/DESIGN

All women receiving antenatal care within six of seven Welsh Health Boards who had an 18 to 20 week ultrasound scan in Welsh NHS Trusts between July 2008 and March 2011 were eligible for inclusion. Data were collected on seven markers (echogenic bowel, cerebral ventriculomegaly, renal pelvicalyceal dilatation, nuchal thickening, cardiac echogenic foci, choroid plexus cysts, and short femur) at the time of 18 - 20 week fetal anomaly scan. Ultrasound records were linked to routinely collected data on pregnancy outcomes (work completed during 2012 and 2013). Images were stored and reviewed by an expert panel.The prevalence of each marker (reported and validated) will be estimated. A projected sample size of 23,000 will allow the prevalence of each marker to be estimated with the following precision: a marker with 0.50% prevalence to within 0.10%; a marker with 1.00% prevalence to within 0.13%; and a marker with 4.50% prevalence to within 0.27%. The relative risk of major congenital abnormalities, stillbirths, pre-term birth and small for gestational age, given the presence of a validated marker, will be reported.

DISCUSSION

This is a large, prospective study designed to estimate the prevalence of markers in a population-based cohort of pregnant women and to investigate associations with adverse pregnancy outcomes. The study will also establish a cohort of children that can be followed-up to explore associations between specific markers and longer-term health and social outcomes.

Factors contributing to intra-uterine fetal death

PURPOSE

We aimed in this research to explore factors contributing to the occurrence of intra-uterine fetal death (IUFD).

METHODS

The study was conducted between 1st January 2008 and 31st December 2009 in the Department of Obstetrics and Gynecology at King Abdulaziz Medical City, Riyadh, Saudi Arabia. Patients who were diagnosed to have IUFD at ≥24 weeks of gestation and those whose dead fetuses were found to weigh ≥500 g after delivery were eligible to be included. 138 patients with IUFD and 237 controls with alive fetuses were enrolled. Data were collected from printed and computerized medical records of participants. Factors that may have contributed to the occurrence of IUFD were explored. Comparisons between various risk factors and outcomes of the two groups were done. p value was statistically significant if ≤0.05.

RESULTS

Patients who did not receive antenatal care (ANC) services are at 70 % increased risk for developing IUFD (OR 0.31, p < 0.0001). Risk of IUFD increases 25-fold with the occurrence of abruption placenta (OR 25.81, p ≤ 0.0001), tenfolds with the occurrence of intra-uterine growth restrictions (OR 10.78, p = 0.04) and threefolds with the presence of hypertensive disorder in pregnancy (OR 3.17, p = 0.04). Finally, patients carrying IUFD fetuses are at higher risk to develop labor complications compared with their controls (p ≤ 0.0001).

CONCLUSION

Despite the difficulty in predicting IUFD occurrence, it appears that carefully implemented ANC and timely management of at risk patients may contribute to its prevention.

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.

The association of maternal BMI with fetal echogenic intracardiac foci and echogenic bowel

OBJECTIVES

To evaluate the impact of maternal body mass index (BMI) as well as maternal ethnicity on the detection of either echogenic intra-cardiac focus (EIF) or echogenic bowel (EB).

METHODS

This prospective study identified 74 uncomplicated singleton fetuses in which EIF and/or EB were detected between 18 and 21 weeks of gestation (i.e. study group). Seventy four consecutively scanned fetuses without EIF or EB, at the same gestational age, were selected as controls. The differences in maternal BMI and maternal ethnicity were compared between the two groups using the chi(2) test, Fisher's exact test, and the Student t-test. A multivariable logistic regression model was constructed to control for confounders. Odds ratios (OR) and their 95% confidence interval (CI) were computed.

RESULTS

The mean maternal BMI was significantly lower in the study group as compared to controls (22.9 +/- 3.1 vs. 28.0 +/- 7.5 kg/m(2), respectively; p < 0.0001). Patients with fetal EIF and/or EB were significantly more likely to be Asians (20.3% vs. 5.4%, OR = 4.5; 95% CI 1.3-16.9). Using a multivariable analysis, controlling for ethnicity, the association between maternal BMI and fetal EIF or EB remained significant (OR = 0.83; 95% CI 0.76-0.91). However, based on this model Asian ethnicity was not an independent risk factor for the detection of EIF and/or EB (OR = 2.6; 95% CI 0.8-8.9).

CONCLUSIONS

Our data suggests an inverse relationship between the maternal BMI and the detection of fetal EIF and/or EB. Moreover, it appears that low maternal BMI, and not Asian ethnicity, is an independent risk factor for the detection of these echogenic fetal findings.

Obstetrical complications associated with abnormal maternal serum markers analytes

OBJECTIVE

To review the obstetrical outcomes associated with abnormally elevated or decreased level of one or more of the most frequently measured maternal serum marker analytes used in screening for aneuploidy. To provide guidance to facilitate the management of pregnancies that have abnormal levels of one of more markers and to assess the usefulness of these markers as a screening test.

OPTIONS

Perinatal outcomes associated with abnormal levels of maternal serum markers analytes are compared with the outcomes of pregnancies with normal levels of the same analytes or the general population.

EVIDENCE

The Cochrane Library and Medline were searched for English-language articles published from 1966 to February 2007, relating to maternal serum markers and perinatal outcomes. Search terms included PAPP-A (pregnancy associated plasma protein A), AFP (alphafetoprotein), hCG (human chorionic gonadotropin), estriol, unconjugated estriol, inhibin, inhibin-A, maternal serum screen, triple marker screen, quadruple screen, integrated prenatal screen, first trimester screen, and combined prenatal screen. All study types were reviewed. Randomized controlled trials were considered evidence of the highest quality, followed by cohort studies. Key individual studies on which the recommendations are based are referenced. Supporting data for each recommendation are summarized with evaluative comments and references. The evidence was evaluated using the guidelines developed by the Canadian Task Force on Preventive Health Care.

VALUES

The evidence collected was reviewed by the Genetics Committee of the Society of Obstetricians and Gynaecologists of Canada.

BENEFITS, HARMS, AND COSTS

The benefit expected from this guideline is to facilitate early detection of potential adverse pregnancy outcomes when risks are identified at the time of a maternal serum screen. It will help further stratification of risk and provide options for pregnancy management to minimize the impact of pregnancy complications. The potential harms resulting from such practice are associated with the so called false positive (i.e., uncomplicated pregnancies labelled at increased risk for adverse perinatal outcomes), the potential stress associated with such a label, and the investigations performed for surveillance in this situation. No cost-benefit analysis is available to assess costs and savings associated with this guideline. SUMMARY STATEMENTS: 1. An unexplained level of a maternal serum marker analyte is defined as an abnormal level after confirmation of gestational age by ultrasound and exclusion of maternal, fetal, or placental causes for the abnormal level. (III) 2. Abnormally elevated levels of serum markers are associated with adverse pregnancy outcomes in twin pregnancies, after correction for the number of fetuses. Spontaneous or planned mutifetal reductions may result in abnormal elevations of serum markers. (II-2) RECOMMENDATIONS: 1. In the first trimester, an unexplained low PAPP-A (< 0.4 MoM) and/or a low hCG (< 0.5 MoM) are associated with an increased frequency of adverse obstetrical outcomes, and, at present, no specific protocol for treatment is available. (II-2A) In the second trimester, an unexplained elevation of maternal serum AFP (> 2.5 MoM), hCG (> 3.0 MoM), and/or inhibin-A (> or =2.0 MoM) or a decreased level of maternal serum AFP (< 0.25 MoM) and/or unconjugated estriol (< 0.5 MoM) are associated with an increased frequency of adverse obstetrical outcomes, and, at present, no specific protocol for treatment is available. (II-2A) 2. Pregnant woman with an unexplained elevated PAPP-A or hCG in the first trimester and an unexplained low hCG or inhibin-A and an unexplained elevated unconjugated estriol in the second trimester should receive normal antenatal care, as this pattern of analytes is not associated with adverse perinatal outcomes. (II-2A) 3. The combination of second or third trimester placenta previa and an unexplained elevated maternal serum AFP should increase the index of suspicion for placenta accreta, increta, or percreta. (II-2B) An assessment (ultrasound, MRI) of the placental-uterine interface should be performed. Abnormal invasion should be strongly suspected, and the planning of delivery location and technique should be done accordingly. (III-C) 4. A prenatal consultation with the medical genetics department is recommended for low unconjugated estriol levels (<0.3 MoM), as this analyte pattern can be associated with genetic conditions. (II-2B) 5. The clinical management protocol for identification of potential adverse obstetrical outcomes should be guided by one or more abnormal maternal serum marker analyte value rather than the false positive screening results for the trisomy 21 and/or the trisomy 18 screen. (II-2B) 6. Pregnant woman who are undergoing renal dialysis or who have had a renal transplant should be offered maternal serum screening, but interpretation of the result is difficult as the level of serum hCG is not reliable. (II-2A) 7. Abnormal maternal uterine artery Doppler in association with elevated maternal serum AFP, hCG, or inhibin-A or decreased PAPP-A identifies a group of women at greater risk of IUGR and gestational hypertension with proteinuria. Uterine artery Doppler measurements may be used in the evaluation of an unexplained abnormal level of either of these markers. (II-2B) 8. Further research is recommended to identify the best protocol for pregnancy management and surveillance in women identified at increased risk of adverse pregnancy outcomes based on an abnormality of a maternal serum screening analyte. (III-A) 9. In the absence of evidence supporting any specific surveillance protocol, an obstetrician should be consulted in order to establish a fetal surveillance plan specific to the increased obstetrical risks (maternal and fetal) identified. This plan may include enhanced patient education on signs and symptoms of the most common complications, increased frequency of antenatal visits, increased ultrasound (fetal growth, amniotic fluid levels), and fetal surveillance (biophysical profile, arterial and venous Doppler), and cervical length assessment. (III-A) 10. Limited information suggests that, in women with elevated hCG in the second trimester and/or abnormal uterine artery Doppler (at 22-24 weeks), low-dose aspirin (60-81 mg daily) is associated with higher birthweight and lower incidence of gestational hypertension with proteinuria. This therapy may be used in women who are at risk. (II-2B) 11. Further studies are recommended in order to assess the benefits of low-dose aspirin, low molecular weight heparin, or other therapeutic options in pregnancies determined to be at increased risk on the basis of an abnormal maternal serum screening analyte. (III-A) 12. Multiple maternal serum markers screening should not be used at present as a population-based screening method for adverse pregnancy outcomes (such as preeclampsia, placental abruption, and stillbirth) outside an established research protocol, as sensitivity is low, false positive rates are high, and no management protocol has been shown to clearly improve outcomes. (II-2D) When maternal serum screening is performed for the usual clinical indication (fetal aneuploidy and/or neural tube defect), abnormal analyte results can be utilized for the identification of pregnancies at risk and to direct their clinical management. (II-2B) Further studies are recommended to determine the optimal screening method for poor maternal and/or perinatal outcomes. (III-A).

Second-trimester fetal growth as a predictor of poor obstetric and neonatal outcome in patients with low first-trimester serum pregnancy-associated plasma protein-A and a euploid fetus

OBJECTIVE

To examine if fetal growth during the second trimester predicts poor pregnancy and neonatal outcome in patients with low first-trimester serum pregnancy-associated plasma protein-A (PAPP-A) and a euploid fetus.

METHODS

We identified all patients with first-trimester PAPP-A<5th centile who had undergone first- and second-trimester ultrasound examination. We excluded multiple pregnancies and those with aneuploidy or major anomalies identified before or after birth. We compared pregnancies with and without ultrasound markers for fetal growth restriction at 18-24 weeks.

RESULTS

We identified 239 patients with low PAPP-A, 25 (10.5%) of whom had evidence of fetal growth restriction at 18-24 weeks. These 25 cases had significantly higher rates of third-trimester small-for-gestational age (SGA) fetus, gestational hypertension, preterm birth, indicated preterm birth, low birth weight and birth weight centiles, 1-min Apgar score<7, neonatal intensive care unit admission and fetal or neonatal death.

CONCLUSION

Among patients with low first-trimester PAPP-A and a euploid fetus, fetal growth in the second trimester can predict poor obstetric and neonatal outcome.

Second-trimester fetal growth and the risk of poor obstetric and neonatal outcomes

OBJECTIVE

To compare outcomes of fetuses with an estimated fetal weight (EFW) < 25(th) percentile in the second trimester to those in fetuses with EFW >or= 25(th) percentile in the second trimester.

METHODS

We compared outcomes of 252 pregnancies with an EFW < 25(th) percentile at 18-24 weeks' gestation with those of 265 controls. All pregnancies had early dating by ultrasonography. We excluded fetuses with aneuploidy, major malformations, second-trimester rupture of membranes, and multiple pregnancies.

RESULTS

Second-trimester EFW < 25(th) percentile was significantly associated with higher rates of fetal or neonatal death, third-trimester small for gestational age (SGA), Doppler abnormalities, indicated preterm birth, gestational hypertension or pre-eclampsia before labor, lower birth weight, birth weight < 10(th) percentile, birth weight < 5(th) percentile, and admission to the neonatal intensive care unit. Many of these associations remained even after excluding patients with oligohydramnios, fetal echogenic bowel, and growth asymmetry.

CONCLUSION

Second-trimester SGA, as defined by an EFW < 25(th) percentile using current growth curves, is associated with poor obstetric and neonatal outcomes. Increased surveillance of such pregnancies may be necessary.

Prenatal ultrasonographic gastrointestinal abnormalities in fetuses with gastroschisis do not correlate with postnatal outcomes

PURPOSE

In the setting of gastroschisis, the clinical significance of prenatal ultrasound findings of secondary changes in bowel appearance remains unknown. The purpose of this study was to correlate prenatal identification of additional gastrointestinal sonographic abnormalities with postnatal clinical outcome.

METHODS

A retrospective review was conducted on 64 fetuses with a prenatal diagnosis of gastroschisis treated at the Children's Hospital of Philadelphia from 2000 to 2007. Postnatal outcomes were compared between newborns with additional sonographic gastrointestinal abnormalities and those without secondary changes to the bowel appearance.

RESULTS

Thirty (47%) patients had at least one gastrointestinal abnormality (eg, bowel dilatation, echogenic bowel, thickened bowel, matted bowel, herniation of the stomach through the abdominal wall defect, or segmental loss of bowel peristalsis) on prenatal ultrasound. There were no significant differences between groups with respect to the time to initial and full enteral nutrition, total hospital stay, requirement for ventilator support, central line infection rates, reoperation rates, or mortality.

CONCLUSIONS

In the setting of gastroschisis, isolated findings of gastrointestinal abnormalities on prenatal ultrasound do not correlate with adverse postnatal outcome.

Foetal magnetic resonance imaging and echogenic bowel

OBJECTIVES

To evaluate how foetal magnetic resonance imaging (MRI) may change the diagnosis in cases of ultrasound (U/S) findings of echogenic bowel (EB).

METHODS

Seventeen foetuses with EB underwent serial U/S examinations, foetal MRI, cystic fibrosis screening and maternal viral serologic tests. MRI protocol included T2-weighted half-Fourier acquired single-shot turbo spin-echo (HASTE) sequence and gradient echo (GE) T1-weighted images. Foetal abdominal MRI analyzed patterns were size and signal of small bowel, colon and rectum, ascites and abdominal mass. All neonates had complete clinical examination, abdominal sonography, and a 6 months clinical follow-up.

RESULTS

Eleven foetuses with isolated EB had normal MRI and normal outcome. In comparison, all the 6 foetuses whose U/S patterns showed associated signs had abnormal MRI (p < 0.001). Five had proven pathology (83.3%: 5/6) and only 1 (16.7%: 1/6) had no proven pathology and normal postnatal outcome (p = 0.001). For those five, foetal MRI showed bowel abnormalities with one case of bowel duplication and four cases of bowel obstruction. Two out of the four cases of bowel obstruction were genetically diagnosed as cystic fibrosis. The two remaining cases were diagnosed as ileal atresia.

CONCLUSION

MRI could provide additive information in cases of EB associated with bowel dilatation.

The Cornell University experience

The authors provide an account of their 20-year-old history of collaborative research and publication at Cornell University on ethics in fetal diagnosis and therapy. This research first developed and applied a conceptual framework for ethics in maternal-fetal medicine based on the concept of the fetus as a patient. The basic elements of this framework are described, as well as their application to fetal diagnosis and fetal therapy. Related topics, including obstetrics and gynecology, clinical medicine, managed care, and the ethical dimensions of medical leadership, are also briefly described.