American Institute of Ultrasound in Medicine. AIUM Practice Guideline for the performance of an antepartum obstetric ultrasound examination

Current status and challenges in prenatal and neonatal screening, diagnosis, and management of congenital heart disease in China

Congenital heart disease (CHD), a wide spectrum of diseases with varied outcomes, is the most common congenital malformation worldwide. In this Series of three papers, we describe the burden of CHD in China; the development of screening, diagnosis, treatment, and follow-up strategies; and challenges associated with the disease. We also propose solutions and recommendations for policies and actions to improve the outcomes of CHD. In the first paper in this Series, we focus on prenatal and neonatal screening, diagnosis, and management of CHD. Based on advanced international knowledge, the Chinese Government has developed a network system comprising prenatal screening, diagnosis of CHD subtypes, specialist consultation appointments, and treatment centres for CHD. A new professional discipline, fetal cardiology, has been formed and rapidly developed. Consequently, the overall coverage of prenatal and neonatal screening and the accuracy of CHD diagnoses have gradually improved, and the neonatal CHD mortality rate has decreased substantially. However, China still faces several challenges in the prevention and treatment of CHD, such as insufficient diagnostic capabilities and unqualified consultation services in some regions and rural areas. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Fetal cavum septum pellucidum nomogram and its relationship with fetal Doppler: a prospective study of a Turkish population

Aim: Septum pellucidum is a thin membrane with right and left leaves, and cavum septum pellucidum (CSP) is formed in the intermembrane region. This study investigates CSP nomogram dimensions for all trimesters in the Turkish population. In addition, the relationship between fetal Doppler flow and CSP size was investigated in this study. Methods: This study was designed as a prospective cohort between 2019-2020. Pregnant women between 19-42 weeks who were followed up at XXX, Department of Obstetrics and Gynecology were included in the study. (blind review) Results: A total of 517 fetuses meeting our criteria were included in this prospective study. In the second trimester (19-28 weeks) CSP width (4.12±0.88 vs. 4.91±1.42, p < 0.001) and length (7.95±1.04 vs. 9.48±2.19, p < 0.001) were significantly higher than in the third trimester (28-42 weeks). While the mean CSP width increased up to 32th weeks, there was no clear increase-decrease pattern between 32th-38th weeks, and it was observed to decrease after 38th weeks. The mean CSP length increased up to 29th weeks, while there was no clear increase-decrease pattern between 29th-38th weeks, but decreased after 38th weeks. While a significant correlation was observed between gestational week and CSP width (r = 0.118, p = 0.010), there was no significant correlation between CSP length (r = 0.086, p =0.062). A significant correlation was observed between biparietal diameter (BPD) and CSP width (r = 0.180, p < 0.001) and length (r = 0.202, p < 0.001), but not with head circumference (HC). There was a significant correlation between middle cerebral artery (MCA) systolic/diastolic ratio (S/D) (r = 0.185, p < 0.001), pulsatility index (PI) (r = 0.210, p < 0.001) and resistive index (RI) (r = 0.233, p < 0.001) and CSP length, but not with CSP width. Conclusion: Turkish population fetal CSP nomogram is presented in this study. Fetal middle cerebral artery Doppler measurements (S/D, PI, and RI) showing cerebral blood flow correlate with CSP length, but not with CSP width. There was no correlation between fetal umbilical artery Doppler measurements and CSP sizes. The results pave the way for population-based studies with much larger samples.

Evaluation of medical malpractice claims in obstetric ultrasonography: Opinion of The Council of Forensic Medicine in Turkey

AIM

The Council of Forensic Medicine is an institution affiliated with the Ministry of Justice in the Republic of Turkey which acts in an official oversight capacity in cases of alleged medical malpractice in forensic medical science. Sonographers may face judicial sanctions as a result of ultrasonography examinations that they do not perform according to current guidelines. In this study we focused our attention to claims of medical malpractice related to obstetric ultrasonography that had been referred to the Council of Forensic Medicine. Our aim was to investigate the causes of malpractice claims related to obstetric ultrasonography and to present the expert opinions of our council about these claims in the light of literature. We have also planned to discuss what can be done with current guideline information to prevent situations that cause malpractice claims.

MATERIALS AND METHODS

The study herein was performed on 73 claims of medical malpractice in obstetric ultrasonography findings, all of which were referred by forensic authorities to the Second Specialization Board of Council Forensic Medicine from 2014 to 2018. A retrospective review of the reports generated from information contained within case files illuminates the reasoning behind medical error claims. Among the reasons examined are features of the ultrasonographic evaluation (number, week of examination, health institution), the traits of the evaluating physicians (institutions, branches, academic titles), congenital anomalies detected after birth, and maternal age.

RESULTS

Analysis of the data shows that 79.5% of ultrasonographic examinations leading to claims of medical malpractice were performed in private health institutions. All cases of medical malpractice claims were associated with undiagnosed congenital anomalies, and that the form for informed consent was obtained for only 19.1% of cases that underwent second level ultrasonographic examination. Further, 53.3% of cases with congenital anomalies subject to litigation were anomalies of the extremities, and all four cases of alleged malpractice within obstetric ultrasonography were associated with extremity anomalies. The variety of academic titles of physicians performing the ultrasonographic examinations was not statistically significant. It was concluded that two ultrasonography examinations performed by two nuclear medicine specialists were not in accordance with medical norms.

CONCLUSION

Although organizations such as AIUM, ACR, and ACOG try to set standards for ultrasound examination through practice guidelines, it is difficult to establish optimal standards for ultrasonographic examination. In light of the guidelines created by the above organizations, each country should set its own standard based on their own socioeconomic and health data. We conclude that it is not appropriate for obstetric ultrasonographic examinations to be performed by specialists in fields such as nuclear medicine, where ultrasonographic examinations are not a part of the core training curriculum. Obtaining a signed informed consent form from the patient prior to the second level ultrasonography examination will be useful for medicolegal defense purposes should a subsequent claim of malpractice be filed.

Sonographic spectrum and postnatal outcomes of early-onset versus late-onset fetal cerebral ventriculomegaly

OBJECTIVES

To review the prenatal characteristics and postnatal outcomes of Early-onset and Late-onset cerebral ventriculomegaly (VM).

METHODS

Single-center retrospective study 2013-2017; VM cases grouped into Early-onset VM (EVM; Diagnosis at/before 24 weeks) and Late-onset VM (LVM; Beyond 24 weeks). LVM cases had normal ventricle width measurement at mid-trimester scan. Infection serology, cytogenetics, MRI, sonographic follow-up, perinatal and neurodevelopmental outcomes were analyzed.

RESULTS

During the 5-year period, 64,662 women underwent an anomaly screening scan and 302 fetuses were identified with ventriculomegaly; 183 (60.6%) classified as early-onset and 119 (39.4%) LVM. The mean ventricular width was significantly higher in LVM cohort (14.1 mm vs 11.6 mm; p < .01). EVM cases were more often associated with structural anomalies (p < .05). Possible etiologies for EVM were aneuploidy and cerebral malformations like Absent Corpus Callosum, spina bifida, Dandy-Walker malformation, etc., whereas LVM followed aqueductal stenosis, hemorrhage, porencephaly, cerebral tumors, etc. Pregnancy outcomes were available for 251 cases. The pregnancy resulted in more live births in LVM group (87.4% vs 65.6%, p = < .01). Multivariate regression analysis demonstrated additional malformations (p < .0001, OR11.5 [95%CI: 4-35.2]), progression of VM (p = .004, OR 10.2 [95% CI: 2.1-52.3]) and severity of VM (OR 5.3 [95%CI: 0.8-37.7]) were significant predictors of Neurodevelopmental Impairment (NDI). Late gestation at diagnosis was more often associated with NDI (p = .063, OR2.4 [95%CI: 0.9-6.2]), although statistically insignificant.

CONCLUSIONS

EVM has a significantly different sonographic spectrum and outcomes compared to LVM. EVM is milder and associated with an increased risk of aneuploidy and structural malformations. LVM often occurs secondary to acquired brain lesions.

Proximal femoral focal deficiency - a rare congenital entity: two case reports and a review of the literature

BACKGROUND

Proximal femoral focal deficiency is an extremely rare congenital anomaly with an incidence of 1.1-2.0 in 100,000 live births. It is a dysplastic phenomenon with predilections for the proximal two-thirds of the femur leading to limb length discrepancies. We report two cases of proximal femoral focal deficiency, which is a rare entity.

CASE PRESENTATIONS

Case 1 A 4.5-month-old baby Annang tribe girl was referred in April 2019 to our Radiology Department, University of Uyo Teaching Hospital, Nigeria for lower limb radiographs. This was on account of her shortened left lower limb from birth despite uneventful antenatal history. An examination revealed bulky left thigh with abduction of her left hip joint. Radiographic evaluations showed absent left femoral capital epiphysis, with deficient proximal left femur. A diagnosis of proximal femoral focal deficiency was made. Sadly, the parents and baby failed to honor future orthopedic consultations on intimation of sequential management protocols. Case 2 A 4-month-old baby Ibibio tribe girl was similarly referred in August 2019 to the same Radiology Department for lower limb conventional radiographs due to short left lower limb that was noticed from birth. An examination showed shortened left lower limb in external rotation. Her right and left lower limbs measured 27 cm and 23 cm, respectively, with landmark taken from anterior superior iliac spine to tip of medial malleolus. A diagnosis of proximal femoral focal deficiency was made. Corroborating radiographs showed shortened and hypoplastic left femoral shaft but preserved femoral capital epiphysis. Coincidentally, the parents have not brought back their baby to our orthopedic clinic.

CONCLUSIONS

The discovery of two cases of proximal femoral focal deficiency, a rare entity, from referrals for conventional radiography in our Radiology Department encourages literature documentation. Such recognition will facilitate early institution of management, thus ensuring meaningful childhood growth.

The Fetal 3-Vessel Views: An Illustrative Case-Based Tutorial

In 2018, the American Institute of Ultrasound in Medicine revised its obstetric Practice Parameter for the second-trimester fetal anatomic survey. The 2018 Practice Parameter recommends incorporation of the 3-vessel view and 3-vessel and trachea view "if technically feasible." Sonographers and other medical providers may require additional training and education to develop greater proficiency in obtaining and interpreting these views. This pictorial essay, including ultrasound images alongside their respective schematic diagrams, provides an up-to-date, practical, and clinically oriented review of the 3-vessel view and 3-vessel and trachea view and their most common presentations in the context of congenital heart disease.

The use of image fusion in prenatal medicine

Fusion imaging (FI), the simultaneous display of the same anatomical region using two imaging modalities, has been used in other areas of medicine for both diagnosis and guiding interventions. Examples include positron emission tomography-computed tomography (PET-CT) imaging in oncology and ultrasound-magnetic resonance imaging (US-MRI) fusion in biopsies of the prostate gland. The underlying principle is to take advantage of the complementary information in each modality to improve accuracy, be it diagnostic accuracy or targeting accuracy in biopsies. For example, PET-CT overlays the metabolic activity of lesions on the superb spatial and anatomical detail of CT. While the historical mainstay of fetal imaging has been ultrasound, advances in ultrafast MR imaging together with advances in fetal MRI over the past two decades, have resulted in the opportunity to explore fusion imaging in fetal medicine. We present an overview of the principles of US-MRI fusion imaging in prenatal medicine, report our local experience, and review the literature in this emerging area. We share our perspective on how FI can improve diagnostic confidence, be used as an educational tool, and potentially enhance guidance in certain fetal procedures.

Intracardiac echogenic focus and its location: association with congenital heart defects

Purpose: Significance of intracardiac echogenic focus (ICEF) in the fetal heart remains controversial. We aimed to investigate whether the location of ICEF is associated with fetal cardiac structure defects (CSDs) in low-risk pregnant women. Materials and Methods: A retrospective cohort study was conducted. Singleton pregnancies with normal values of triple fetal serum markers were included. 758 of 9782 fetuses with ICEF were reviewed for involvement of three ICEF locations (left, right, and bilateral ventricles (BVs)) in CSDs. χ² or Fisher's exact test was performed for statistical analysis. Results: ICEF prevalence was 7.7% and its location was most frequently in the left ventricle (LV) (84.8%), followed by the BV (11.6%) and the right ventricle (RV) (3.6%). No statistically significant difference was found between the ICEF location and maternal age (χ² = 3.92, p-value = .1409). There were cardiac defects with an isolated echogenic focus in 24 of 758 fetuses (3.2%). Significant difference for CSDs was observed among groups of RV, LV, and BV (p-fisher = .0146). Conclusions: Significantly more CSDs cases were identified in fetuses with ICEF in RV. Further investigation is warranted to examine the histological characteristics of fetal echogenic focus in the RV.

Sensitivity of prenatal ultrasound for detection of trisomy 18

Objectives: To evaluate the sensitivity of prenatal ultrasound (US) for trisomy (T18) diagnosis and describe US findings in a large tertiary care institution in the USA. Materials and methods: This was a retrospective cohort of all T18 cases diagnosed at our institution from October 2004 to October 2014 based on prenatal or postnatal genetic diagnostic testing. We included all women with a fetus affected by T18 who had a comprehensive US by a maternal-fetal medicine specialist performed at our institution. US findings were reviewed, classified by organ system, and categorized as an anomaly or soft marker. Chi-square or t-test was used for statistical analysis. Results: We included 128 cases of T18 with confirmed cytogenetic analysis -110 (86%) of which were diagnosed prenatally or suspected by cell-free DNA and confirmed postnatally, and 18 of which underwent neonatal blood sampling alone. One hundred and twenty-one (95%) had at least one abnormal US finding. Anomalies were more frequently identified on US at ≥20 weeks as compared with <20 weeks (93% versus 76%; p = .004). The mean number of findings detected per fetus was 5.1 ± 3.0. Fetuses diagnosed by postnatal sampling alone had a similar number of US exams performed and number of abnormal findings compared to those diagnosed prenatally. Conclusion: Ninety-five percent of fetuses with T18 had at least one abnormal US finding. This sensitivity of is higher than reported in most prior studies, but is not 100%, and should be considered when counseling women regarding prenatal diagnosis of T18. Rationale: Historical detection rates for abnormal sonographic findings in trisomy 18 fetuses range from 70% to 100%. These studies are limited by small sample sizes. This is a contemporary study of ultrasound findings in a large group of women with confirmed trisomy 18 by prenatal or postnatal genetic diagnosis. We provide expansive detail on soft markers and anomalies broken down by organ-system and gestational age.

Isolated Single Umbilical Artery and Fetal Echocardiography: A 25-Year Experience at a Tertiary Care City Hospital

OBJECTIVES

To review our 25-year experience with a single umbilical artery and fetal echocardiography to estimate the need for this test in cases of an isolated single umbilical artery.

METHODS

We conducted a retrospective review of 436 patients with a diagnosis of a single umbilical artery at our institution between 1990 and 2015. Two hundred eighty-eight women had both an anatomic survey and a fetal echocardiogram. Pregnancies with concurrent extracardiac anomalies or aneuploidy were excluded. The study population was divided into 3 groups based on cardiac views on the anatomic survey: normal, incomplete, and suspicious. Echocardiographic results were compared among the 3 groups. The primary outcome measure was the incidence of cardiac anomalies in the normal group at fetal echocardiography. The data were analyzed by the χ² test or Fisher exact test.

RESULTS

The mean maternal age ± SD of the group was 29.2 ± 6.2 years; 44.1% were primiparas. The mean gestational age at diagnosis was 22.6 ± 5.2 weeks, and the mean gestational age at fetal echocardiography was 25.1 ± 3.6 weeks. In the normal group, 99.1% (230 of 232) of women had a normal fetal echocardiogram; the 2 abnormal cases were ventricular septal defects. Normal echocardiograms were obtained in 81.8% (36 of 44) and 25.0% (3 of 12) of the "incomplete" and "suspicious" groups, respectively.

CONCLUSIONS

Fetuses with a single umbilical artery, in the absence of structural abnormalities, and with normal cardiac views at the time of the anatomic survey do not warrant an echocardiogram.

Aborted fetal sizes of Thoroughbred horses in Hidaka, Japan, between 2005 and 2015

The degree of fetal growth restriction has been unclear in equine reproduction. In this study, 2,195 fetuses from 2,137 abortions during 11 seasons were examined to determine the causes of abortion, and fetal size dimensions (crown rump length and body weight) were measured. In total, 900 cases (42.1%) of abortion were identified as caused by viral infection (215, 10.1%), bacterial infection (156, 7.3%), fungal infection (25, 1.2%), circulation failure (406, 19.0%), multiple causes (66, 3.1%), deformity (13, 0.6%), placental abnormality (12, 0.6%), and other causes (7, 0.3%). All viral infections originated from equine herpes virus. Of all abortions, 94.3% occurred between 181–360 days of pregnancy, and the gestational ages at abortion were different based on the causes. Fetal sizes in viral abortions were considerably larger than those due to other reasons. Compared with viral infection, the crown rump length size dimension of fetuses aborted from multiple and fungal infection was affected. In addition, bacterial infection, circulation failure, and unknown causes of abortions also contributed to growth restriction in terms of body weight. In conclusion, the present study showed details of equine abortion and the relationships between causes of abortion and fetal size. Most of the aborted fetuses showed restrictions in their growth. The manifestations of growth restriction were more related to weight than skeletal length.

A comparison of standard two-dimensional ultrasound to three-dimensional volume sonography for routine second-trimester fetal imaging

OBJECTIVE

In comparison with standard two-dimensional (2D) imaging of fetal structure and biometry, we aimed to evaluate the role of three-dimensional (3D) imaging as a screening tool in the mid-trimester.

STUDY DESIGN

Pregnant women presenting between 18and 22 weeks for routine anatomical survey and biometric measurements were recruited. Six volumes of fetal anatomic regions were obtained and archived for later reconstruction, along with three volumes of extra-fetal structures (placenta, cervix, amniotic fluid). The 2D standard fetal images were then obtained. Offline reconstruction of 3D volumes was performed for comparative analysis (2D vs 3D). Subsequently, 3D volumes were reconstructed to mirror traditional 2D and allow biometric comparison between the two techniques. Data of 98 patients were analyzed.

RESULTS

Complete visualization of vital anatomic structures was seen ⩾85% of the time with 3D ultrasound. The 3D imaging improved the assessment of the four heart chambers (P=0.003), thoracic spine (P=0.008) and lumbar spine (P=0.012) views. The 2D imaging was superior for the fetal head, placenta and upper limbs. Conditional probabilities were used to assess the clinical value of 3D when standard 2D views were incomplete (mean 0.8830; 95% confidence interval 0.8059 to 0.9320). Overall diagnostic accuracy of 3D ultrasound is not superior for all fetal anatomic structures. Fetal biometric measurements assessed by both techniques demonstrated substantial to excellent agreement.

CONCLUSION

The use of 3D imaging as a primary screening tool is limited and may be best utilized as a second-stage test. Overall, there is good correlation between fetal biometry assessed by either 2D or 3D technology.

Congenital Heart Disease Requiring Maintenance of Ductus Arteriosus in Critically Ill Newborns Admitted at a Tertiary Neonatal Intensive Care Unit

Introduction

Congenital heart diseases (CHD) have been reported to be responsible for 30 to 50% of infant mortality caused by congenital disabilities. In critical cases, survival of newborns with CHD depends on the patency of the ductus arteriosus (PDA), for maintaining the systemic or pulmonary circulation. The aim of the study was to assess the efficacy and side effects of PGE (prostaglandin E) administration in newborns with critical congenital heart disease requiring maintenance of the ductus arteriosus.

Material and method

All clinical and paraclinical data of 66 infants admitted to one referral tertiary level academic center and treated with Alprostadil were analyzed. Patients were divided into three groups: Group 1: PDA dependent pulmonary circulation (n=11) Group 2: PDA dependent systemic circulation (n=31) Group 3: PDA depending mixed circulation (n=24).

Results

The mean age of starting PGE1 treatment was 2.06 days, 1.91 (+/-1.44) days for PDA depending pulmonary flow, 2.39 (+/-1.62) days for PDA depending systemic flow and 1.71 (+/1.12) for PDA depending mixing circulation. PEG1 initiation was commenced 48 hours after admission for 72%, between 48-72 hours for 6%, and after 72 to 120 hours for 21% of newborns detected with PDA dependent circulation. Before PEG1 initiation the mean initial SpO2 was 77.89 (+/- 9.2)% and mean initial oxygen pressure (PaO2) was 26.96(+/-6.45) mmHg. At the point when stable wide open PDA was achieved their mean SpO2increased to 89.73 (+/-8.4)%, and PaO2 rose to 49 (+/-7.2) mmHg. During PGE1 treatment, eleven infants (16.7%) had apnea attacks, five children (7.5%) had convulsions, 33 (50%) had fever, 47 (71.2%) had leukocytosis, 52 (78.8%) had edema, 25.8% had gastrointestinal intolerance, 45.5% had hypokalemia, and 63.6% had irritability.

Conclusions

For those infants with severe cyanosis or shock caused by PDA dependent heart lesions, the initiation and maintenance of PGE1 infusion is imperative. The side effects of this beneficial therapy were transient and treatable.

Completion and Sensitivity of the Second-Trimester Fetal Anatomic Survey in Obese Gravidas

OBJECTIVES

To estimate the effect of maternal body mass index (BMI) on the completion of fetal anatomic surveys before 20 weeks' estimated gestational age (GA).

METHODS

We conducted a retrospective cohort study of singletons undergoing standard or detailed anatomic sonographic examinations from 2006 to 2014. Patients were categorized by ranges of BMI. The primary outcomes were completion of standard and detailed anatomic surveys before 20 weeks' estimated GA. The effect of the BMI category was assessed by the χ² test for trends and analysis of variance.

RESULTS

Of 15,313 patients, 5917 (38%) were obese, and 1581 (10%) had a BMI of 40 kg/m² or higher. Standard (P < .01) and detailed (P < .01) surveys were less likely to be completed as the BMI category increased. Suboptimal visualization of the fetal chest (P < .01), abdomen (P < .01), and extremities (P < .01) significantly contributed to the decreased standard survey completion rates. Suboptimal visualization of the fetal head (P < .01) and chest (P < .01) significantly contributed to the decreased detailed survey completion rates. There was no statistically significant difference in the sensitivity of a completed standard or detailed anatomic survey for the detection of fetal anomalies.

CONCLUSIONS

An increasing BMI category was associated with decreased completion of standard and detailed anatomic surveys by 20 weeks' estimated GA. Strategies to improve early visualization of the fetal head, chest, and abdomen in obese women should be investigated to promote anomaly detection and appropriate counseling.

Association of Fetal Choroid Plexus Cysts With Trisomy 18 in a Population Previously Screened by Nuchal Translucency Thickness Measurement

OBJECTIVE

The study's aim was to determine any association between choroid plexus cysts (CPCs) and trisomy 18 in a population of fetuses previously screened by nuchal translucency (NT) thickness measurement.

METHODS

During the study period (May 1999 to December 2004), 7,795 fetuses had an NT scan and second-trimester fetal anatomical scan at our institution. The prevalence of trisomy 18 was determined among four types of pregnancies: 1) those with isolated CPCs, 2) those with CPCs and enlarged NT, 3) those with CPCs and other ultrasound markers, and 4) those with CPCs, enlarged NT, and other ultrasound markers. The fetal outcome according to NT and presence of CPCs was calculated. Incidence rates of enlarged NT and CPCs in fetuses with trisomy 18 and fetuses with normal chromosomes were also evaluated.

RESULTS

For the entire population, ten trisomy 18 cases were diagnosed prenatally (prevalence, 0.13%). Among fetuses with enlarged NT, the likelihood ratio of trisomy 18 was significantly increased in fetuses with CPCs compared with fetuses without such cysts (333.6 versus 15.2, P = .002). However, among fetuses with normal NT, no significant difference was demonstrated for likelihood ratio of trisomy 18 between fetuses with and without CPCs.

CONCLUSION

In pregnancies complicated by isolated CPCs, fetal karyotyping is not indicated when no additional anomaly is detected on ultrasonographic examination and first-trimester NT results are normal.

Labor and Delivery Experiences of Mothers with Suspected Large Babies

OBJECTIVE

To characterize the prevalence of and factors associated with clinicians' prenatal suspicion of a large baby; and to determine whether communicating fetal size concerns to patients was associated with labor and delivery interventions and outcomes.

METHODS

We examined data from women without a prior cesarean who responded to Listening to Mothers III, a nationally representative survey of women who had given birth between July 2011 and June 2012 (n = 1960). We estimated the effect of having a suspected large baby (SLB) on the odds of six labor and delivery outcomes.

RESULTS

Nearly one-third (31.2%) of women were told by their maternity care providers that their babies might be getting "quite large"; however, only 9.9% delivered a baby weighing ≥4000 g (19.7% among mothers with SLBs, 5.5% without). Women with SLBs had increased adjusted odds of medically-induced labor (AOR 1.9; 95% CI 1.4-2.6), attempted self-induced labor (AOR 1.9; 95% CI 1.4-2.7), and use of epidural analgesics (AOR 2.0; 95% CI 1.4-2.9). No differences were noted for overall cesarean rates, although women with SLBs were more likely to ask for (AOR 4.6; 95% CI 2.8-7.6) and have planned (AOR 1.8; 95% CI 1.0-4.5) cesarean deliveries. These associations were not affected by adjustment for gestational age and birthweight.

CONCLUSIONS FOR PRACTICE

Only one in five US women who were told that their babies might be getting quite large actually delivered infants weighing ≥4000 g. However, the suspicion of a large baby was associated with an increase in perinatal interventions, regardless of actual fetal size.

What is prenatal screening and why to do it?

Patients and providers are faced with a wide array of choices to screen for structural abnormalities, aneuploidy, and genetic diseases in the prenatal period. It is important to consider the features of the diseases being screened for, the characteristics of the screening tests used, and the population being screened when evaluating prenatal screening techniques.

Is routine preoperative transthoracic echocardiography necessary in newborns with myelomeningocele?

OBJECTIVE

Congenital heart disease (CHD) is common in newborns with myelomeningocele. Echocardiography before neonatal back closure has been recommended. Its utility in the era of prenatal diagnosis is unclear.

STUDY DESIGN

We reviewed all newborns with myelomeningocele evaluated by preoperative echocardiography at our institution over 11 years.

RESULT

Seventy-six successive newborns were identified. Ninety-one percent were prenatally diagnosed with myelomeningocele. In all, 1% had critical, 12% critical or non-critical and 22% critical, non-critical or possible CHD. The single case of critical CHD was both prenatally diagnosed and clinically identifiable.

CONCLUSION

The prevalence of CHD in newborns with myelomeningocele is increased compared with the general population; however, critical disease is uncommon. We propose preoperative echocardiography is unnecessary when the myelomeningocele is prenatally diagnosed, antenatal cardiac screening is complete and normal, and the newborn is clinically well.

Detection of critical congenital heart defects: Review of contributions from prenatal and newborn screening

In 2011, statewide newborn screening programs for critical congenital heart defects began in the United States, and subsequently screening has been implemented widely. In this review, we focus on data reports and collection efforts related to both prenatal diagnosis and newborn screening. Defect-specific, maternal, and geographic factors are associated with variations in prenatal detection, so newborn screening provides a population-wide safety net for early diagnosis. A new web-based repository is collecting information on newborn screening program policies, quality indicators related to screening programs, and specific case-level data on infants with these defects. Birth defects surveillance programs also collect data about critical congenital heart defects, particularly related to diagnostic timing, mortality, and services. Individuals from state programs, federal agencies, and national organizations will be interested in these data to further refine algorithms for screening in normal newborn nurseries, neonatal intensive care settings, and other special populations; and ultimately to evaluate the impact of screening on outcomes.

Ultrasonographic evaluation of equine fetal growth throughout gestation in normal mares using a convex transducer

It has not been common to perform regular ultrasound examination of the fetus in equine practice, due to the increasing volume of the uterus caused by fetal development. The convex three-dimensional transducer is bulb-shaped and is able to observe wide areas. In addition, its operation is simple, making it easy to create appropriate angles for various indices using a transrectal approach. The aim of this study was to measure Thoroughbred fetal growth indices throughout gestation using a convex transducer and to clarify the detectable period of some indices for clinical use. We demonstrated changes in fetal indices, such as crown rump length (CRL), fetal heart rate (FHR), fetal eye and kidney and the combined thickness of uterus and placenta (CTUP). CTUP increased from 30 weeks of gestation, and FHR peaked at 8 weeks and then decreased to term. CRL could be observed until 13 weeks due to its wide angle, longer than in previous reports. Fetal eye and kidney could be observed from 10 and 28 weeks, respectively, and these increased with pregnancy progress. The present results showed the advantage of transrectal examination using a convex transducer for evaluation of normal fetal development. Although ultrasonographic examination in mid- to late-gestation is not common in equine reproductive practice, our comprehensive results would be a useful basis for equine pregnancy examination.

Timing of ultrasound in pregnancy--how often? At what intervals?

The second trimester fetal anatomic survey has continued to evolve over the past 27 years. This review will summarize the changes in the anatomic survey that have occurred and provide recommendations that serve to improve compliance with the components of the survey. In order to provide clarity and direction, the goals and limitations of the second trimester fetal anatomic survey should be defined. The visualization rate of specific fetal anatomic structures can be increased by specifying acceptable, alternative views. A single follow-up examination within 2-4 weeks of a fetal anatomic survey or before 22 weeks' gestation should be offered when specific components of the fetal anatomic survey cannot be visualized. The fetal anomalies that the anatomic survey seeks to identify should be defined along with an acceptable detection rate.

A pictorial guide for the second trimester ultrasound

Introduction: The second trimester ultrasound remains an important screening tool for detecting fetal abnormalities. This pictorial guide for the second trimester ultrasound is designed to assist practitioners to produce a high quality diagnostic survey of the fetus by demonstrating and describing recommended images. Methods: Each image is discussed in detail and has an associated drawn line diagram to aid in the identification of the important features of that image. There is a description of the salient landmarks and relevant measurements. Result: The authors hope this article may act as a useful guide to all practitioners performing second trimester ultrasounds.

Ultrasound methodology used to construct the fetal growth standards in the INTERGROWTH-21st Project

A unified protocol is essential to ensure that fetal ultrasound measurements taken in multicentre research studies are accurate and reproducible. This paper describes the methodology used to take two-dimensional, ultrasound measurements in the longitudinal, fetal growth component of the INTERGROWTH-21(st) Project. These standardised methods should minimise the systematic errors associated with pooling data from different study sites. They represent a model for carrying out similar research studies in the future.

Sonographic accuracy of estimated fetal weight in twins

OBJECTIVES

We aimed to determine the accuracy of sonographic formulas for estimating birth weight in twin pregnancies.

METHODS

We conducted a retrospective cohort study of consecutive twin pregnancies undergoing sonography at within 1 week of delivery. Pregnancies were included if biometric measurements and birth weight were available and excluded if anomalies were present. Estimated fetal weight was calculated using three sonographic formulas: two derived from singletons (Hadlock and Shepard) and one from twins (Ong). The correlation between estimated fetal weight and birth weight was determined using the Pearson correlation coefficient. The accuracy of each formula (bias) was assessed using the mean percentage error [(estimated fetal weight - birth weight)/birth weight × 100], and the precision (random error) was estimated from the standard deviation of the percentage error. The screening efficiency of each formula for intrauterine growth restriction, defined as below the 10th percentile on the Alexander growth standard, was assessed. The effect of twin presentation was determined using a paired analysis.

RESULTS

Of 1744 consecutive twin pregnancies, 270 (540 infants) met inclusion criteria. The estimated fetal weight of all 3 formulas strongly correlated with the birth weight (Pearson r = 0.90 for Hadlock, 0.87 for Shepard, and 0.92 for Ong). Each formula had similar sensitivity (65%-70%) and specificity (85%-90%) for intrauterine growth restriction. For each formula, the correlation coefficient was similar between twins A and B (Pearson r = 0.85-0.93); however, the estimated fetal weight for twin A tended to underestimate birth weight, whereas the estimated fetal weight for twin B tended to overestimate birth weight.

CONCLUSIONS

Three widely used estimated fetal weight formulas, two derived from singletons and one from twins, perform equally well in estimating birth weight in twin gestations.

Fetal diagnosis and imaging in cardiology

BACKGROUND

Fetal echocardiography plays a critical role in the diagnosis and management of structural, functional and rhythm-related fetal cardiovascular disease.

OBJECTIVES/METHODS

This article reviews the history of fetal echocardiography and the prenatal diagnosis of fetal cardiovascular disease as well as the evolution of the field of fetal cardiology. The clinical application of fetal echocardiography, including indications for referral, timing of referral and considerations in the diagnosis and serial assessment of fetal cardiovascular disease, is presented.

CONCLUSIONS

Newer directions in the field of fetal cardiology, including first trimester diagnoses and fetal intervention, will continue to expand its role in the evaluation and treatment of affected pregnancies in the future; however, equally as important are efforts to continue to improve prenatal detection rates.

Detection of the fetal conotruncal anomalies using real-time three-dimensional echocardiography with live xPlane imaging of the fetal ductal arch view

OBJECTIVE

To evaluate the role of live xPlane imaging of ductal arch view in detection of fetal conotruncal anomalies.

METHODS

Two hundred selected singleton pregnancies, including 152 normal cases, 27 conotruncal anomalies and 21 other types of fetal heart abnormalities were enrolled in this observational study. All the cases were scanned to visualize the ductal arch view with live xPlane imaging by a single observer. The detection rate of conotruncal and non-conotruncal anomalies with live xPlane imaging was compared.

RESULTS

In using this new method of live xPlane imaging, an abnormal ductal arch view was visualized in 92.6% of fetal conotruncal anomalies, compared with that of non-conotruncal anomalies (23.8%, p < 0.001).

CONCLUSION

The ductal arch view can be obtained by live xPlane imaging. This method is relatively simple and feasible, hence may be a useful tool to detect fetal conotruncal anomalies.

[Could we perform quality second trimester ultrasound among obese pregnant women?]

OBJECTIVE

To compare the quality of second trimester ultrasound images and their anatomical quality scores among obese women and those with a normal body mass index (BMI).

MATERIALS AND METHODS

This prospective study, which took place from 2009 to 2011, included every obese pregnant woman (prepregnancy BMI greater than 30 kg/m(2)) who had an ultrasound examination at 20 to 24 weeks in our hospital and a control group with a normal BMI (20-24.9kg/m(2)) who had the same examination. A single operator evaluated the quality of all images, reviewing the standardized ultrasound planes - three biometric and six anatomical - required by French guidelines and scoring the quality of the six anatomical images. Each image was assessed according to 4-6 criteria, each worth one point. We sought excellent quality, defined as the frequency of maximum points for a given image.

RESULTS

The obese group included 223 women and the control group 60. The completion rate for each image was at least 95 % in the control group and 90 % in the obese group, except for diaphragm and right outflow tract images. Overall, the excellence rate varied from 35 % to 92 % in the normal BMI group and 18 % to 58 % in the obese group and was significantly lower in the latter for all images except abdominal circumference (P=0.26) and the spine (P=0.06). Anatomical quality scores were also significantly lower in the obese group (22.3 vs. 27.2 ; P=0.001).

CONCLUSION

Image quality and global anatomical scores in second trimester ultrasound scans were significantly lower among obese than normal-weight women.

Factors affecting feasibility and quality of second-trimester ultrasound scans in obese pregnant women

OBJECTIVES

To evaluate the feasibility of completing in one session a second-trimester ultrasound scan in obese pregnant women, to compare the quality of images obtained with those of non-obese women and to analyze factors that can improve the completion rate.

METHODS

This prospective study, from 2009 to 2011, included all obese pregnant women (prepregnancy body mass index (BMI) > 30 kg/m2) who had an ultrasound examination at 20-24 weeks in our department, and a control group of pregnant women with normal BMI (20-24.9 kg/m2) who had the same examination. A single operator reviewed the standardized ultrasound images (three biometric and six to assess key anatomical features) required under French guidelines, to assess their presence, evaluate the quality of all images and score the quality of the six anatomical images. Each image was assessed according to between four and six criteria, each worth one point. We sought excellent quality, defined as the frequency of maximum points for a given image type. The factors associated with completing the scan in one session were evaluated with multivariate logistic regression.

RESULTS

The obese group included 223 women and the control group 60; a complete scan in one session was achieved in 70.4% and 81.7% of these, respectively (P = 0.08). The completion rate for each image type was at least 95% in the control group and 90% in the obese group, except for diaphragm and right outflow tract images. Significant factors associated with completing the scan in the multivariate model were: having 10 additional minutes for the scan (P = 0.03), moving the fetus so that the back was in posterior or lateral position (P = 0.01), more experienced sonographer (P = 0.03) and thinner maternal abdominal wall thickness (P = 0.01). Overall, the excellence rate varied from 35% to 92% in the normal BMI group and from 18% to 58% in the obese group, and was significantly lower in the latter for all images except abdominal circumference (P = 0.26) and spine (P = 0.06). Anatomical quality scores were also significantly lower in the obese group (22.3 vs. 27.2; P = 0.001).

CONCLUSION

Although ultrasound scans of obese pregnant women are feasible, image quality and global anatomical scores are significantly lower among obese than normal-weight women. However, certain simple improvements may increase fetal visualization.

Can live xPlane imaging of the in-plane view of interventricular septum be used to detect fetal conotruncal anomalies?

OBJECTIVE

To evaluate the feasibility of live xPlane imaging visualizing the in-plane view of IVS in the screening of the fetal conotruncal anomalies.

METHOD

One hundred and fifty-two consecutive normal singleton fetuses and forty-eight fetal cardiac defects (27 conotruncal and 21 non-conotruncal cases), were enrolled in this study. The in-plane view of IVS was firstly acquired with live xPlane imaging and then judged whether it is normal or not by one operator. The focus was put on observing the relationship of pulmonary artery and aorta. The comparison between conotruncal and non-conotruncal anomalies in demonstrating the relationship of pulmonary artery and aorta was performed.

RESULT

There were 27 cases of conotruncal anomalies enrolled in this study and 19 cases (70.4%) had the abnormal relationship of aorta and pulmonary artery in the in-plane view of IVS. In 21 cases of non-conotruncal CHDs, however, there were only 5 cases (23.8%) had the abnormal relationship in the in-plane view of IVS (p < 0.001).

CONCLUSION

Live xPlane imaging of the in-plane view of IVS is feasible to detect the fetal conotruncal anomalies, which may potentially be a useful tool for the non-experienced operators to screen the fetal conotruncal anomalies.

Prevalence, natural history, and clinical outcome of mild to moderate ventriculomegaly

OBJECTIVE

To estimate the prevalence, associated anomalies, progression, and clinical outcome in fetuses diagnosed with mild to moderate ventriculomegaly at 18-24 weeks of pregnancy.

METHODS

This was a prospective population-based study from the North of England. Data were extracted from the U.K. Northern Congenital Abnormality Survey for cases identified during 1994-2008. Additional anomalies present were categorized according to European Surveillance of Congenital Anomalies guidelines. Differences between isolated and nonisolated ventriculomegaly were examined by either Fisher's exact test or Mann-Whitney U test. Changes in prevalence were examined by the χ² test for trend.

RESULTS

There were 355 cases of confirmed mild to moderate ventriculomegaly in singleton pregnancies at 18-24 weeks of gestation among 454,080 registered births, giving a total prevalence of 7.8 per 10,000 registered births (95% confidence interval [CI] 7.0-8.7). The minimum rate of chromosomal anomaly and trisomy 21 (including cases karyotyped postnatally) in isolated cases (ie, in which no other structural anomaly was identified prenatally) was 10.2% (95% CI 6.1-16.0) and 4.5% (95% CI 2.0-8.7), respectively. Additional structural anomalies were identified prenatally in 43.1% of cases. Among isolated cases, 61.9% (95% CI 53.3-70.0) resolved by the final prenatal scan (the majority by 24 weeks of gestation) and 10.7% (95% CI 6.4-16.6) were found to have "missed" structural anomalies after birth. The probability of an infant death for isolated ventriculomegaly was 3% (95% CI 0.8-7.6).

CONCLUSION

This register-based study on mild to moderate ventriculomegaly provides unique epidemiologic and outcome data. Information from this study should aid in counseling parents.

LEVEL OF EVIDENCE

III.

Detailed ultrasound screening in the second trimester: pictorial essay of normal fetal anatomy

Today, ultrasound is the main diagnostic tool in the prenatal detection of congenital abnormalities. Therefore, ultrasound examination should be offered to all pregnant women. A detailed sonographic examination of the fetus is usually performed between 18 and 22 weeks of pregnancy. The accurate recognition of normal fetal anatomy is very important for the detection of both minor and major defects. The purpose of this pictorial essay is to show fetal anatomic structures, which have to be examined between the 18(th) and 22(nd) weeks of pregnancy, and present their standard measurements systematically and thoroughly in accordance with sonographically obtained ideal sections.

Decreased echogenicity of the embryo is correlated with absence of cardiac activity

PURPOSE

The purpose of this study was to investigate whether the sonographic echogenicity of embryos is associated with cardiac activity in utero.

METHODS

The present study reviewed a total of 164 embryos having a gestational age between 6 and 8 weeks. These embryos were examined by transvaginal ultrasonography and a comparison of their echogenicity was made with respect to those of the placenta and the myometrium. Grade II embryos were less echogenic than the placenta or had similar echogenicity with the myometrium, whereas grade I embryos shared the same echogenicity as the placenta. In contrast, grade III embryos were less echogenic than the myometrium.

RESULTS

Most of the embryos with cardiac activity were detected to have grade II echogenicity (78/130, 60.0%), whereas the remaining embryos had grade I echogenicity (52/130, 40.0%). In contrast, most of the embryos without cardiac activity had grade III echogenicity (20/34, 58.8%), whereas the remaining embryos had either grade II (8/34, 23.5%) or grade I (6/34, 17.7%) echogenicity.

CONCLUSIONS

Decreased echogenicity of embryos on grayscale ultrasound in the early first trimester is correlated with an absence of cardiac activity.

Standardization of fetal ultrasound biometry measurements: improving the quality and consistency of measurements

OBJECTIVE

To assess whether a standardization exercise prior to commencing a fetal growth study involving multiple sonographers can reduce interobserver variation.

METHODS

In preparation for an international study assessing fetal growth, nine experienced sonographers from eight countries participated in a standardization exercise consisting of theoretical and practical sessions. Each performed a set of seven standard fetal measurements on pregnant volunteers at 20-37 weeks' gestation, and these were repeated by the lead sonographer; all measurements were taken in a blinded fashion. After this the sonographers had hands-on practice and feedback sessions on other volunteers. This process was repeated three times. Measurement differences between sonographers and the lead sonographer, expressed as a gestational-age-specific Z-score, between the first and third scans were compared using the Wilcoxon signed ranks test, and variance was assessed using Pitman's test. Interobserver agreement was also assessed using the intraclass correlation coefficient (ICC), and all images were scored for quality in a blinded fashion.

RESULTS

At baseline the level of agreement and image scoring were high. A significant reduction in the differences between sonographers and the lead sonographer were seen for fetal biometry overall (head circumference, abdominal circumference and femur length) between the first and third scans (median Z-scores, 0.46 and 0.24; P = 0.005), and a reduction in the variance was also observed (P < 0.001). The ICCs for measurement pairs for every fetal measurement showed a clear trend of increasing ICC (better agreement) with consecutive training scan sessions, although no improvement in image scores was seen.

CONCLUSION

Even for experienced sonographers, a standardization exercise before starting a study of fetal biometry can improve consistency of measurements. This could be of relevance for studies assessing fetal growth in multicenter sites.

Vermian biometric parameters in the normal and abnormal fetal posterior fossa: three-dimensional sonographic study

OBJECTIVES

The purposes of this study were to describe a 3-dimensional sonographic technique for evaluation of the fetal vermis and to compare vermian biometric parameters in fetuses with a normal and an abnormal posterior fossa.

METHODS

A prospective study was conducted from 2006 through 2008 on 12 fetuses with an abnormal posterior fossa and 73 healthy control fetuses from 18 to 35 weeks' gestation. Three-dimensional scans of the fetal head were performed in the axial plane, using static volume contrast imaging in the C-plane. The vermian perimeter, cross-sectional area, and superoinferior diameter were measured and compared between abnormal and normal fetuses using the Wilcoxon nonparametric test. Linear regression analysis was used to describe trends of the vermis during gestation. The z scores for perimeter, cross-sectional area, and superoinferior diameter measurements in the abnormal posterior fossa group in each 2-week interval were calculated.

RESULTS

Twelve fetuses with an abnormal posterior fossa were recruited: 3 with a Blake pouch cyst, 1 vermian cyst, 1 enlarged cisterna magna, 2 Dandy-Walker malformation, 4 partial vermian agenesis, and 1 hemicerebellar hypoplasia. The vermian cross-sectional area was reduced significantly in the fetuses with an abnormal posterior fossa compared with the control fetuses starting at 18 to 19 weeks' gestation (P = .01); the mean vermian superoinferior diameter was lower only from 22 to 23 weeks (P = .01); and the mean vermian perimeter was decreased from 28-29 weeks' gestation (P = .03). Linear regression analysis of the parameters showed that fetuses with an abnormal posterior fossa had a statistically significantly lower growth rate than control fetuses during gestation (P < .001).

CONCLUSIONS

Measurements of the cross-sectional area were more useful than those of the perimeter and superoinferior diameter in distinguishing between fetuses with a normal and an abnormal posterior fossa during the early stages of gestation.

Online evaluation of fetal second-trimester four-chamber view images: a comparison of six evaluation methods

OBJECTIVE

To compare six online evaluation methods for auditing routine second-trimester four-chamber view still images.

METHODS

We evaluated three different scoring grids (subjective, five-item score and seven-item score), which were applied with or without access to online help, resulting in a total of six evaluation methods. For the subjective scoring grid, images were rated as excellent, good, fair, poor or very poor. For the five-item score, 1 point was allocated for visualization (vs non-visualization or non-evaluable) of each of: heart crux, atria, ventricles, apex and aorta, yielding a score of 0-5. For the seven-item score, 1 point was allocated for clear (vs unclear) visualization of each of: moderator band at the apex, interventricular septum, atrioventricular valves, non-linear insertion of atrioventricular valves (normal offset), septum primum, aorta and pulmonary vein. Each evaluation method was used via the Internet by three randomly selected reviewers, who evaluated the same set of 80 images. Reviewers were experienced in fetal ultrasound, but were not involved in the design of the study. Interrater agreement was the main outcome.

RESULTS

The five-item scoring grid with online help achieved the best interrater agreement (interrater intraclass correlation coefficient = 0.7).

CONCLUSIONS

Evaluation of the second-trimester sonographic four-chamber view is apparently best achieved with a simple five-item scoring grid.

Scan the fetal heart by real-time three-dimensional echocardiography with live xPlane imaging

OBJECTIVE

To describe the methodology of live xPlane imaging in the visualization of the fetal heart in detail.

METHODS

Fifty-one consecutive pregnant women with singleton pregnancies were imaged to display four screening sections of the fetal heart, the four-chamber view, the left outflow tract view (LVOT), the right outflow tract view (RVOT), and the three-vessel and trachea view (3VT), using live xPlane imaging. The methodology of how to visualize the screening planes was described in detail. We used two methods to image the fetal heart with live xPlane imaging: one uses the four-chamber view as the starting plane and the other uses the longitudinal view of fetal upper thorax as the starting plane.

RESULTS

When using the four-chamber view as the starting plane, the visualization rate of LVOT, RVOT, and 3VT was 94.1% (48/51), 100% (51/51), and 98.0% (50/51), respectively. When using the longitudinal view as the starting plane, the visualization rate of four-chamber view, LVOT, RVOT, and 3VT was 100% (51/51), 100% (51/51), 41.2% (21/51), and 100% (51/51), respectively.

CONCLUSIONS

Live xPlane imaging can be used to visualize the screening views of the fetal heart, and potentially may be a useful tool for the assessment and diagnosis of fetal congenital heart diseases.

Fetuses with ventriculomegaly diagnosed in the second trimester of pregnancy by in utero MR imaging: what happens in the third trimester?

BACKGROUND AND PURPOSE

Although MR imaging of the fetal brain has been shown to provide additional diagnostic information, the optimal timing of the study and the value of repeat studies remain unclear. The primary purpose of this study was to look for structural abnormalities of the fetal brain shown at 30-32 weeks' gestational age but not on the 20-24 weeks' study in fetuses originally referred with isolated VM. In particular, we wished to study the hypothesis that third-trimester fetal MR imaging studies would not show extra brain abnormalities compared with the second-trimester studies in this group.

MATERIALS AND METHODS

Ninety-nine women were admitted for a fetal MR study between 20-24 weeks' gestational age, and 46 of these women agreed to return for a second MR imaging examination at 30-32 weeks' gestational age. The other women were either lost to follow-up or declined the invitation to return. Two experienced observers measured the width of the trigones, and the results were compared, to test reliability. Changes in the degree of VM are reported along with changes in the diagnosis of structural brain abnormalities.

RESULTS

There was excellent reproducibility of trigone measurements between the 2 observers, with a mean absolute difference of <1 mm in the 40 fetuses that were ultimately shown to have isolated VM. Twenty-eight of 40 fetuses studied had mild VM on the first iuMR imaging examination, but in just more than half, the category of VM changed between the studies (5 had become normal-sized, 7 had progressed to moderate, 3 had become severe, and 13 remained mild). In 1 case, hypogenesis of the corpus callosum was recognized at 30-32 weeks but had not been reported on the 20-24 weeks' examination; the other 5 fetuses had brain pathology recognized on both fetal MR studies.

CONCLUSIONS

Trigone measurements can be made in a highly repeatable fashion on iuMR imaging. We have not shown any major advantage in repeating iuMR imaging at 30-32 weeks' gestation in terms of improved diagnosis of other structural brain abnormalities. With the converse of that argument, however, our data suggest that there is no advantage in delaying iuMR imaging studies to 30-32 weeks in the hope of improving detection rates.

Effect of placenta previa on fetal growth

OBJECTIVE

To estimate the association between placenta previa and abnormal fetal growth.

STUDY DESIGN

Retrospective cohort study of consecutive women undergoing ultrasound between 15 and 22 weeks. Groups were defined by the presence or absence of complete or partial placenta previa. The primary outcome was intrauterine growth restriction (IUGR), defined as a birthweight <10th percentile by the Alexander growth standard. Univariable, stratified, and multivariable analyses were used to estimate the effect of placenta previa on fetal growth restriction.

RESULTS

Of 59,149 women, 724 (1.2%) were diagnosed with a complete or partial previa. After adjusting for significant confounding factors (black race, gestational diabetes, preeclampsia, and single umbilical artery), the risk of intrauterine growth restriction remained similar (adjusted odds ratio, 1.1; 95% confidence interval, 0.9-1.5). The presence of bleeding did not impact the risk of growth restriction.

CONCLUSION

Placenta previa is not associated with fetal growth restriction. Serial growth ultrasounds are not indicated in patients with placenta previa.

Comparison of single versus multiple echogenic foci in the fetal heart regarding risk of aneuploidy

OBJECTIVE

The purpose of this study was to investigate whether multiple echogenic cardiac foci (ECF) are associated with an increased risk of fetal trisomy 21 in our patient population.

METHODS

During a span of 38 months, all women found to have an ECF on obstetric sonography were identified as study patients and grouped into single- and multiple-ECF groups. Age- and race-matched patients were identified as a control group. Fetal anatomic sonographic examinations were assessed for other markers of aneuploidy and major abnormalities. The baseline risk for trisomy 21 was assessed by maternal serum screening or age alone if no serum screening had been performed. Trisomy 21 was assessed by amniocentesis or clinically at birth. Both univariate and multivariate analyses were used to assess for associations with trisomy 21.

RESULTS

Six of 71 patients (8.5%) with multiple ECF and 1 of 171 patients (0.6%) with a single ECF had trisomy 21. One of 242 control patients (0.4%) had trisomy 21. Logistic regression found multiple ECF (P < .008), the presence of a major finding or multiple minor findings (P = .0012), and a baseline risk for trisomy 21 of greater than 1 in 100 (P = .003) as independent associations with trisomy 21.

CONCLUSIONS

Our results suggest that finding multiple ECF is a stronger predictor of trisomy 21 than what is described for a single ECF.