Maternal obesity limits the ultrasound evaluation of fetal anatomy

Panniculus Retractor Use for Visualization of Fetal Anatomy: A Randomized Controlled Trial

OBJECTIVE

To evaluate whether use of a panniculus retractor device for pregnant patients with body mass index (BMI) 40 or higher and a panniculus improves the completion rate of the fetal anatomic examination.

METHODS

This was a randomized trial in which eligible patients with BMI 40 or higher and a panniculus were randomized to undergo their detailed fetal anatomic examination with a panniculus retractor device in place compared with usual care. The primary outcome was the completion rate of 16 prespecified views from the anatomic examination. Secondary outcomes included completion rate of all 64 views from our institution's detailed anatomic examination, duration of examination, major fetal anomaly detection rate, depth from the skin to amniotic cavity before and after retractor placement, patient and ultrasonographer satisfaction, and prespecified adverse events. We assumed a baseline completion rate of 23% for the primary outcome and targeted a twofold improvement with 80% power and two-sided α of 0.05, which resulted in a sample size of 132 participants. The goal enrollment was increased to 150 participants to account for potential dropout. Statistical tests included the Student's t test, χ2, and relative risks (RRs) as appropriate.

RESULTS

From March to July of 2023, 150 participants completed the study: 74 in the retractor group and 76 in the usual care group. Baseline characteristics were similar between groups except for panniculus grade. The completion rate of 16 prespecified views was 25.7% (19/74) in the retractor group and 31.6% (24/76) in the control group (RR 0.81, 95% CI, 0.49-1.35). There were no significant differences between groups for any of the secondary outcomes. Patient satisfaction and ultrasonographer satisfaction were similar between groups.

CONCLUSION

Use of a panniculus retractor device during the fetal anatomic examination for patients with BMI 40 or higher and a panniculus was well tolerated by patients and ultrasonographers but did not improve the completion rate of 16 prespecified fetal anatomic views.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT05764408.

Expectations and basic knowledge in ultrasound screening among pregnant women: A questionnaire survey

OBJECTIVE

This study aimed to evaluate the disparity of the expectations and basic knowledge of prenatal ultrasound (US) screening among pregnant women and make a comparison with the current scientific knowledge and national recommendations. We hypothesize that sociodemographic factors, including age, education, and professional occupation, may be associated with different levels of knowledge.

METHODS

This was a cross-sectional study performed in 2021 of 336 women aged 18 to 46 years in a maternity facility in a tertiary hospital in Portugal. The main outcome measures were questionnaire data from questions divided into four categories (sociodemographic, expectations, knowledge, and final considerations/suggestions). The data were grouped according to the sociodemographic factors (age, educational level, and professional occupation) and analyzed and compared as a function of the social groups as well as overall tendencies.

RESULTS

Our data confirmed a significant discrepancy between the expectations and general knowledge of pregnant women regarding prenatal US when compared with the current scientific knowledge. Importantly, we found that both depended greatly on sociodemographic factors, particularly educational level. This reiterated the importance of conducting effective dissemination actions of current scientific knowledge, focusing on the main objectives of US screening as well as the limitations of the existing technology.

CONCLUSION

This study will help in defining strategies for future dissemination actions aiming to improve current practice and lead to a higher synchrony of expectations towards US between couples and practitioners.

Completion of Fetal Anatomy Evaluations in Women With Body Mass Index ≥ 50 kg/m2

OBJECTIVES

As maternal body mass index (BMI) increases, fetal anatomy ultrasound becomes more challenging, less sensitive, and less likely to be complete. We sought to report our experience of incomplete evaluation of anatomy in patients with BMI of 50 kg/m2 or greater.

METHODS

This is a retrospective cohort of singleton gestations in mothers with BMI of 50 kg/m2 or greater, undergoing anatomy evaluations between 2017 and 2021 at 9 maternal-fetal-medicine sites in Houston, TX. Patient variables and scan results were collected throughout pregnancy to provide a longitudinal assessment of the primary outcome, completion rate (percent of all scans which optimally captured 24 American Institute of Ultrasound in Medicine-recommended images). Secondary outcomes included the rate of optimal capture of each individual structure.

RESULTS

In total, 293 patients with BMI ≥50 kg/m2 were identified. Only 28% of initial scans were complete, but over the entire pregnancy, a complete anatomic evaluation was achieved in 76% of women, largely due to weekly ultrasounds done for antenatal testing later in pregnancy. Neither BMI, placental location, nor amniotic fluid volume affected completion rate. The most difficult views are the outflow tracts, 4-chamber view, and spine.

CONCLUSIONS

One quarter of women with BMI of 50 kg/m2 or greater will not have a complete fetal anatomic evaluation by the end of pregnancy, since even basic fetal anatomic views are technically challenging to complete. Solutions deserve further attention, and may include first trimester imaging, transvaginal imaging, and optimization of ultrasound machine settings.

The Effects of Obesity on Health Care Delivery

The rates of obesity continue to rise among adults and children in the United States; hence, it is natural that obesity is reshaping health care delivery. This is seen in numerous ways, including physiologic, physical, social, and economic impacts. This article reviews a broad range of topics, from the effects of increased adiposity on drug pharmacokinetics and pharmacodynamics to the changes health care environments are making to accommodate patients with obesity. The significant social impacts of weight bias are reviewed, as are the economic consequences of the obesity epidemic. Finally, a patient case that demonstrates the effects of obesity on health care delivery is examined.

Recasting Current Knowledge of Human Fetal Circulation: The Importance of Computational Models

Computational hemodynamic simulations are becoming increasingly important for cardiovascular research and clinical practice, yet incorporating numerical simulations of human fetal circulation is relatively underutilized and underdeveloped. The fetus possesses unique vascular shunts to appropriately distribute oxygen and nutrients acquired from the placenta, adding complexity and adaptability to blood flow patterns within the fetal vascular network. Perturbations to fetal circulation compromise fetal growth and trigger the abnormal cardiovascular remodeling that underlies congenital heart defects. Computational modeling can be used to elucidate complex blood flow patterns in the fetal circulatory system for normal versus abnormal development. We present an overview of fetal cardiovascular physiology and its evolution from being investigated with invasive experiments and primitive imaging techniques to advanced imaging (4D MRI and ultrasound) and computational modeling. We introduce the theoretical backgrounds of both lumped-parameter networks and three-dimensional computational fluid dynamic simulations of the cardiovascular system. We subsequently summarize existing modeling studies of human fetal circulation along with their limitations and challenges. Finally, we highlight opportunities for improved fetal circulation models.

Impact of maternal body mass index on the accuracy of third trimester sonographic estimation of fetal weight

OBJECTIVES

To Determine whether maternal body mass index (BMI) can affect the accuracy of sonographic estimation of fetal weight (EFW) in the third trimester when compared to neonatal birthweight (BW).

METHODS

Secondary analysis from our original prospective cohort of pregnant women beyond 34 weeks, distributed in 4 groups according to their BMI: normal, overweight, obese and morbid obese. Fetal biometry and fluid measurements were obtained by two experienced sonographers, blinded for patient's clinical information and to each other's measurements. Average EFW and neonatal BW were converted into gestational-specific Z-scores. Interobserver correlation coefficient (ICC) and Cronbach's reliability coefficient (CRC) were calculated. Bland-Altman (BA) plots were constructed to assess the level of accuracy.

RESULTS

100 women were enrolled (800 measurements obtained by 17 sonographers): 17 had normal BMI (17%), 27 were overweight (27%), 29 were obese (29%) and 27 were morbidly obese (27%). There was no statistical difference for GA at delivery (p = 0.74), EFW (p = 0.05) or BW (p = 0.09) between groups (Table 1). Mean Z-score for EFW was - 0.17 (SD 0.81) and for neonatal BW was - 0.25 (SD 0.74). ICC was 0.69 (95% CI 0.57, 0.78) and CRC was 0.82. Mean Z-score difference was small (Table 2). When stratifying according to BMI categories, the ICC ranged from 0.49 to 0.76. Reliability indices ranged from 0.66 to 0.86. The Z-scores' differences were overall small with no statistical difference (Table 3). BA showed evenly distributed interobserver differences (Fig. 1).

CONCLUSIONS

When performed by trained sonographers, fetal weight estimation in the third trimester is accurate when compared to neonatal birthweight at increasing BMI categories.

Clinical Applications of B-Flow Ultrasound: A Scoping Review of the Literature

Coded excitation ultrasound investigations have the potential to augment the resolution, increase the efficiency, and expand the possibilities of noninvasive diagnostic imaging. B-Flow ultrasound, a type of digitally encoded imaging, was developed more than 20 years ago with the aim to optimize the visualization of blood flow. It has been investigated for a plethora of applications so far. A scoping review regarding its clinical applications was conducted based on a systematic literature research. B-Flow has been investigated in various anatomic locations and pathologies. However, previous research is limited by small sample sizes, the rare occurrence of elaborate study designs, the reliance on subjective reports and qualitative data, as well as several potential biases. While results are in general promising, it should therefore still be considered an emerging technology. Nevertheless, the limitations can be addressed in future research and the potential to expand its applications make B-Flow an interesting candidate for further investigations.

Perception of the impact of maternal weight on pregnancy outcomes in overweight and obese women

OBJECTIVE

The purpose of this study was to assess and compare knowledge, self-awareness, and accuracy of perceived risks and weight status among overweight and obese women.

METHODS

This study was a secondary analysis of a cross-sectional questionnaire study of overweight and obese pregnant women who sought a routine first-trimester screening ultrasound. Those with a pre-pregnancy body mass index (BMI) ≥25 kg/m² (calculated using self-reported height and weight) were included. Perceived associations between estimated weight category and risk of pregnancy complications were assessed and compared in the overweight and obese groups. The perceived weight category was compared to an estimated weight category. A logistic regression identified the demographic and medical factors associated with correct identification of risk factors.

RESULTS

A total of 169 participants (88 overweight; 81 obese) were included. Most participants believed their weight did not impact the ultrasound detection of a fetal malformation (92.1% overweight vs. 55.6% obese, p < .01). Few participants associated their weight with pregnancy-related problems (6.8% overweight vs. 24.7% obese, p < .01). Most participants did not associate their weight with specific maternal complications (72.7% overweight vs. 45.7% obese, p < .01) and fetal complications (83.0% overweight vs. 71.6% obese, p = .08). More obese than overweight women underestimated their weight category (64.4% vs 41.3% overweight, p = .01). Women who correctly estimated their weight status, non-Hispanic participants, and those with a history of depression or at least one maternal co-morbidity were more likely to associate their weight with increased risk for pregnancy-related problems.

CONCLUSION

Although more obese than overweight women associated excess weight with pregnancy complications, both groups underestimated the impact on their pregnancies. Targeted educational programs are needed to improve the risk perception of these populations prior to pregnancy with the goal of improving their weight statuses and pregnancy outcomes.

Determination of anatomic level of myelomeningocele by prenatal ultrasound

PURPOSE

Ultrasound is the primary method for prenatal identification of myelomeningocele and is critical to prognostication and treatment planning. No study has considered the degree of inaccuracy of prenatal US lesion level estimates and anatomic lesion level on postnatal imaging using the weighted kappa coefficient (κw), nor the impact of maternal BMI on agreement. We examined the accuracy of prenatal ultrasound lesion level estimation in a cohort of patients with myelomeningocele using κw and determined whether BMI influenced accuracy.

METHODS

The study is a retrospective review including patients born 2011-2019 who had prenatal imaging and primary myelomeningocele closure at a single institution. Lesion levels from prenatal ultrasound and postnatal imaging studies were analyzed for agreement at exact level, within 1 level, and within 2 levels using κw. Maternal BMI was examined for correlation with accuracy.

RESULTS

Fifty-seven patients met inclusion criteria. Mean BMI was 31.2. There was no association between maternal BMI and agreement at any level. Lesion level on prenatal ultrasound agreed with postnatal imaging to the exact level in 13 (22.8%) cases, within 1 level in 38 (66.7%) cases, and within 2 levels in 50 (87.7%) cases. Weighted kappa showed moderate agreement at exact level (κ_w = 0.494) and substantial agreement within 1 (κ_w = 0.761) and 2 levels (κ_w = 0.902).

CONCLUSION

Weighted kappa adds confidence for clinical decision making by accounting for accuracy. Prenatal ultrasound is a reliable and accurate method of determining lesion level with near-perfect agreement to postnatal imaging within 2 spinal levels. Maternal BMI may not influence lesion level determination after initial diagnosis.

Programming of cardiometabolic health: the role of maternal and fetal hyperinsulinaemia

Obesity and gestational diabetes during pregnancy have multiple short- and long-term consequences for both mother and child. One common feature of pregnancies complicated by maternal obesity and gestational diabetes is maternal hyperinsulinaemia, which has effects on the mother and her adaptation to pregnancy. Even though insulin does not cross the placenta insulin can act on the placenta as well affecting placental growth, angiogenesis and lipid metabolism. Obese and gestational diabetic pregnancies are often characterised by maternal hyperglycaemia resulting in exposure of the fetus to high levels of glucose, which freely crosses the placenta. This leads to stimulation of fetal ß-cells and insulin secretion in the fetus. Fetal hyperglycaemia/hyperinsulinaemia has been shown to cause multiple complications in fetal development, such as altered growth trajectories, impaired neuronal and cardiac development and early exhaustion of the pancreas. These changes could increase the susceptibility of the offspring to develop cardiometabolic diseases later in life. In this review, we aim to summarize and review the mechanisms by which maternal and fetal hyperinsulinaemia impact on (i) maternal health during pregnancy; (ii) placental and fetal development; (iii) offspring energy homeostasis and long-term cardiometabolic health; (iv) how interventions can alleviate these effects.

Protocol for the e-POWUS Project: multicentre blinded-randomised controlled trial of ultrasound speed choice to improve sonography quality in pregnant women with obesity

INTRODUCTION

During pregnancy, maternal obesity increases the risk of fetal abnormalities. Despite advances in ultrasound imaging, the assessment of fetal anatomy is less thorough among these women. Currently, the construction of ultrasound images uses a conventional ultrasound propagation velocity (1540 m/s), which does not correspond to the slower speed of propagation in fat tissue.The main objective of this randomised study is to compare the completeness of fetal ultrasonography according to whether the operator could choose the ultrasound velocity (1420, 1480 or 1540 m/s) or was required to apply the 1540 m/s velocity.

METHODS AND ANALYSIS

This randomised trial is an impact study to compare a diagnostic innovation with the reference technique. The trial inclusion criteria require that a pregnant woman with obesity be undergoing a fetal morphology examination by ultrasound from 20⁺⁰ to 25⁺⁰ gestational weeks.Randomisation will allocate women into two groups. The first will be the 'modulable speed' group, in which operators can choose the speed of ultrasound propagation to be considered for the morphological analysis: 1420, 1480 or 1540 m/s. In the second 'conventional speed' group, operators will perform the morphological examination with the ultrasound speed fixed at 1540 m/s. The adjudication committee, two independent experts, will validate the completeness of each examination and the quality of the images.

ETHICS AND DISSEMINATION

This research protocol does not change the standard management. The only possible impact is an improvement of the ultrasound examination by improving the quality of the image and the completeness of morphological examination. The Agence du Médicament et produits de santé approved this study (2018-A03478-47). The anonymised data will be available on request from the principal investigator. Results will be reported in peer-reviewed journals and at scientific meetings.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (http://www.clinicaltrials.gov) Registry (NCT04212234).

Assessment of the fetal thymus gland: Comparing MRI-acquired thymus volumes with 2D ultrasound measurements

OBJECTIVES

The fetal thymus gland has been shown to involute in response to intrauterine infection, and therefore could be used as a non-invasive marker of fetal compartment infection. The objective of this study was to evaluate how accurately 2D ultrasound-derived measurements of the fetal thymus reflect the 3D volume of the gland derived from motion corrected MRI images.

STUDY DESIGN

A retrospective study was performed using paired ultrasound and MRI datasets from the iFIND project (http://www.ifindproject.com). To obtain 3D volumetry of the thymus gland, T2-weighted single shot turbo spin echo (ssTSE) sequences of the fetal thorax were acquired. Thymus volumes were manually segmented from deformable slice-to-volume reconstructed images. To obtain 2D ultrasound measurements, previously stored fetal cine loops were used and measurements obtained at the 3-vessel-view (3VV) and 3-vessel-trachea view (3VT): anterior-posterior diameter (APD), intrathoracic diameter (ITD), transverse diameter (TD), perimeter and 3-vessel-edge (3VE). Inter-observer and intra-observer reliability (ICC) was calculated for both MRI and ultrasound measurements. Pearson correlation coefficients (PCC) were used to compare 2D-parameters with acceptable ICC to TV.

RESULTS

38 participants were identified. Adequate visualisation was possible on 37 MRI scans and 31 ultrasound scans. Of the 30 datasets where both MRI and ultrasound data were available, MRI had good interobserver reliability (ICC 0.964) and all ultrasound 3VV 2D-parameters and 3VT 3VE had acceptable ICC (>0.75). Four 2D parameters were reflective of the 3D thymus volume: 3VV TD r = 0.540 (P = 0.002); 3VV perimeter r = 0.446 (P = 0.013); 3VV APD r = 0.435 (P = 0.110) and 3VT TD r = 0.544 (P = 0.002).

CONCLUSIONS

MRI appeared superior to ultrasound for visualization of the thymus gland and reproducibility of measurements. Three 2D US parameters, 3VV TD, perimeter and 3VT APD, correlated well with TV. Therefore, these represent a more accurate reflection of the true size of the gland than other 2D measurements, where MRI is not available.

A comparative study of ultrasound and cross-sectional imaging for detection of small renal masses: anatomic factors and radiologist's experience

Objective:

To evaluate anatomic factors and radiologist's experience in the detection of solid renal masses on ultrasonography.

Methods:

We searched for solid renal masses diagnosed on cross-sectional imaging from 2007 to 2017 that also had previous ultrasonography from the past 6 months. The following features were evaluated: nodule size, laterality, location and growth pattern, patient body mass index and radiologist's experience in ultrasound. In surgically resected cases, pathologic reports were evaluated. Unpaired t test and χ² test were used to evaluate differences among subgroups, using R-statistics. Statistical significance was set at p<0.05.

Results:

The initial search of renal nodules on cross-sectional imaging resulted in 428 lesions and 266 lesions were excluded. Final cohort included 162 lesions and, of those, 108 (67%) were correctly detected on ultrasonography (Group 1) and 54 (33%) were missed (Group 2). Comparison of Groups 1 and 2 were as follows, respectively: body mass index (27.7 versus 27.1; p=0.496), size (2.58cm versus 1.74cm; p=0.003), laterality (54% versus 59% right sided; p=0.832), location (27% versus 22% upper pole; p=0.869), growth pattern (25% versus 28% endophytic; p=0.131) and radiologist's experience (p=0.300). From surgically resected cases, histology available for Group 1 was clear cell (n=11), papillary (n=15), chromophobe (n=2) renal cell carcinoma, oncocytoma (n=1), and, for Group 2, clear cell (n=7), papillary (n=5) renal cell carcinoma, oncocytoma (n=2), angiomyolipoma, chromophobe renal cell carcinoma, and interstitial pyelonephritis (n=1, each).

Conclusion:

Size was the only significant parameter related to renal nodule detection on ultrasound.

Delay of Fetal Anatomy Ultrasound Assessment Based on Maternal Body Mass Index Does Not Reduce the Rate of Inadequate Visualization

OBJECTIVES

To determine whether delay of initial anatomy ultrasound based on the maternal body mass index (BMI) reduces the rate of inadequate visualization compared to standard timing at 18^0/7 to 19^6/7 weeks.

METHODS

A retrospective study of singleton anatomy assessments was conducted at a tertiary care center in the 2-year period before (A, 2012-2014) and after (B, 2014-2016) protocol initiation. Assessments in period B were scheduled on the basis of the BMI in the first trimester: lower than 25 kg/m² , 18^0/7 to 19^6/7 weeks; 25 to 29.9 kg/m² , 19^0/7 to 20^6/7 weeks; 30 to 34.9 kg/m² , 20^0/7 to 21^6/7 weeks; 35 to 39.9 kg/m² , 21^0/7 to 22^6/7 weeks; and 40 kg/m² or higher, 22^0/7 to 23^6/7 weeks. In period A, assessments were scheduled between 18^0/7 and 19^6/7 weeks. The rate of inadequate visualization and repeated assessments in periods A and B were compared. Multivariable logistic regression, per-protocol, and BMI subgroup analyses were completed.

RESULTS

In total, 3491 pregnancies in period A and 3672 in period B were included. In period B, 74% were scheduled per protocol; however, this rate decreased for higher-BMI categories (52% for BMI ≥40 kg/m² ). The inadequate visualization rate was slightly higher in period B versus A (16.9% versus 15.0%; P = .03) and exceeded 35% for a BMI of 40 kg/m² or higher, with or without delay. After adjusting for maternal age and fetal presentation, period B had small increased odds of inadequate visualization versus period A (adjusted odds ratio, 1.2; 95% confidence interval, 1.02-1.38). Repeated assessment rates were similar in periods B and A (14.0% versus 13.1%; P = .25).

CONCLUSIONS

In pregnancies with obesity, a protocol delaying the initial assessment beyond 19^6/7 weeks based on the maternal BMI does not reduce the rate of inadequate visualization.

Impact of maternal obesity on fetal cardiac screening: which follow-up strategy is cost-effective?

OBJECTIVE

To perform a cost-effectiveness analysis of different follow-up strategies for non-obese and obese women who had incomplete fetal cardiac screening for major congenital heart disease (CHD).

METHODS

Three decision-analytic models, one each for non-obese, obese and Class-III-obese women, were developed to compare five follow-up strategies for initial suboptimal fetal cardiac screening. The five strategies were: (1) no follow-up ultrasound (US) examination but direct referral to fetal echocardiography (FE); (2) one follow-up US, then FE if fetal cardiac views were still suboptimal; (3) up to two follow-up US, then FE if fetal cardiac views were still suboptimal; (4) one follow-up US and no FE; and (5) up to two follow-up US and no FE. The models were designed to identify fetuses with major CHD in a theoretical cohort of 4 000 000 births in the USA. Outcomes related to neonatal mortality and neurodevelopmental disability were evaluated. A cost-effectiveness willingness-to-pay threshold was set at US$100 000 per quality-adjusted life year (QALY). Base-case and sensitivity analysis and Monte-Carlo simulation were performed.

RESULTS

In our base-case models for all body mass index (BMI) groups, no follow-up US, but direct referral to FE led to the best outcomes, detecting 7%, 25% and 82% more fetuses with CHD in non-obese, obese and Class-III-obese women, respectively, compared with the baseline strategy of one follow-up US and no FE. However, no follow-up US, but direct referral to FE was above the US$100 000/QALY threshold and therefore not cost-effective. The cost-effective strategy for all BMI groups was one follow-up US and no FE. Both up to two follow-up US with no FE and up to two follow-up US with FE were dominated (being more costly and less effective), while one follow-up US with FE was over the cost-effectiveness threshold. One follow-up US and no FE was the optimal strategy in 97%, 93% and 86% of trials in Monte-Carlo simulation for non-obese, obese and Class-III-obese models, respectively.

CONCLUSION

For both non-obese and obese women with incomplete fetal cardiac screening, the optimal CHD follow-up screening strategy is no further US and immediate referral to FE; however, this strategy is not cost-effective. Considering costs, one follow-up US and no FE is the preferred strategy. For both obese and non-obese women, Monte-Carlo simulations showed clearly that one follow-up US and no FE was the optimal strategy. Both non-obese and obese women with initial incomplete cardiac screening examination should therefore be offered one follow-up US. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Fetal Anomaly Detection in Pregnancies With Pregestational Diabetes

OBJECTIVES

To evaluate fetal anomaly detection in pregnancies with pregestational diabetes, according to the gestational age at the time of specialized sonography, use of follow-up sonography, maternal body mass index, and organ system(s) involved.

METHODS

Women with pregestational diabetes who received prenatal care and delivered a live-born or stillborn neonate at our hospital from October 2011 through April 2017 were ascertained. We included all pregnancies with at least 1 confirmed structural anomaly (EUROCAT classification) who had detailed sonography at 18 weeks' gestation or later. We analyzed detection of anomalous fetuses at the initial detailed sonogram and, if no abnormality was identified, during any follow-up sonograms. Statistical analyses were performed with the χ² test and Mantel-Haenszel χ² test for trend.

RESULTS

Seventy-two anomalous neonates (72 of 1060 [6.8%]) were born. Overall detection was 55 of 72 (76%); 49 of 72 (68%) were detected at the initial detailed sonogram, compared to 6 of 15 (40%) of follow-up examinations (P = .04). Recognition at the initial or follow-up examination was not dependent on gestational age or body mass index category (all P > .05). Of individual organ system anomalies, 67 of 89 (75%) were identified. Detection exceeded 85% for central nervous system, genitourinary, and musculoskeletal abnormalities and 43% for craniofacial anomalies. Sixty-five percent of cardiac anomalies were detected, and 14 of 17 (82%) requiring specialized care in the immediate neonatal period were recognized.

CONCLUSIONS

Approximately three-fourths of anomalous fetuses were identified, with greater detection at the initial detailed examination. Fetuses with central nervous system, genitourinary, musculoskeletal abnormalities and those with cardiac anomalies requiring specialized cardiac care were more likely to come to attention.

Guideline No. 391-Pregnancy and Maternal Obesity Part 1: Pre-conception and Prenatal Care

OBJECTIVE

This guideline will review key aspects in the pregnancy care of women with obesity. Part I will focus on pre-conception and pregnancy care. Part II will focus on team planning for delivery and Postpartum Care.

INTENDED USERS

All health care providers (obstetricians, family doctors, midwives, nurses, anaesthesiologists) who provide pregnancy-related care to women with obesity.

TARGET POPULATION

Women with obesity who are pregnant or planning pregnancies.

EVIDENCE

Literature was retrieved through searches of Statistics Canada, Medline, and The Cochrane Library on the impact of obesity in pregnancy on antepartum and intrapartum care, maternal morbidity and mortality, obstetrical anaesthesia, and perinatal morbidity and mortality. Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to September 2018. Grey (unpublished) literature was identified through searching the websites of health technology assessment and related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the authors. Then the Maternal-Fetal Medicine Committee peer reviewed the content and submitted comments for consideration, and the Board of the Society of Obstetricians and Gynaecologists of Canada (SOGC) approved the final draft for publication. Areas of disagreement were discussed during meetings, at which time consensus was reached. The level of evidence and quality of the recommendation made were described using the Evaluation of Evidence criteria of the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in these guidelines may increase obstetrical provider recognition of the issues affected pregnant individuals with obesity, including clinical prevention strategies, communication between the health care team, the patient and family as well as equipment and human resource planning. It is hoped that regional, provincial and federal agencies will assist in the education and support of coordinated care for pregnant individuals with obesity.

GUIDELINE UPDATE

SOGC guidelines will be automatically reviewed 5 years after publication. However, authors can propose another review date if they feel that 5 years is too short/long based on their expert knowledge of the subject matter.

SPONSORS

This guideline was developed with resources funded by the SOGC.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Maternal Overweight and Obesity and Risk of Congenital Heart Defects

BACKGROUND

Congenital heart defects are more frequent in offspring of mothers with overweight or obesity. However, associations between maternal overweight and obesity, and risks of complex and specific heart defects are not clear.

OBJECTIVES

This study sought to analyze associations between maternal overweight and obesity severity and rates of complex and specific heart defects.

METHODS

This was a population-based cohort study in Sweden, including 2,050,491 live singleton infants born between 1992 and 2012. Data on maternal and infant characteristics, and diagnoses of congenital heart defects were retrieved from nationwide registries. Maternal body mass index (BMI) was categorized as underweight (BMI <18.5 kg/m²), normal weight (BMI 18.5 to <25 kg/m²), overweight (BMI 25 to <30 kg/m²), obesity class I (BMI 30 to <35 kg/m²), class II (BMI 35 to <40 kg/m²), and class III (BMI ≥40 kg/m²). Outcomes included complex heart defects (tetralogy of Fallot, transposition of the great arteries, atrial septal defects [ASD], aortic arch defects, and single-ventricle heart) and subgroups of specific heart defects diagnosed up to 5 years of age. The authors calculated adjusted prevalence rate ratios (PRRs) with 95% confidence intervals.

RESULTS

A total of 28,628 (1.40%, N = 2,050,491) children had at least 1 congenital heart defect. PRRs of aortic arch defects increased with maternal obesity severity. Compared with offspring of normal weight mothers, PRRs of aortic arch defects and transposition of the great arteries were doubled in offspring of mothers with severe obesity. PRRs of ASD and persistent ductus arteriosus in term infants increased with maternal BMI.

CONCLUSIONS

PRRs of aortic branch defects, ASD, and persistent ductus arteriosus increase with maternal obesity severity.

Congenital left heart obstruction: ethnic variation in incidence and infant survival

OBJECTIVE

To investigate the relationship between ethnicity and health outcomes among fetuses and infants with congenital left heart obstruction (LHO).

DESIGN

A retrospective population-based review was conducted of fetuses and infants with LHO including all terminations, stillbirths and live births from 20 weeks' gestation in New Zealand over a 9-year period. Disease incidence and mortality were analysed by ethnicity and by disease type: hypoplastic left heart syndrome (HLHS), aortic arch obstruction (AAO), and aortic valve and supravalvular anomalies (AVSA).

RESULTS

Critical LHO was diagnosed in 243 fetuses and newborns. There were 125 with HLHS, 112 with AAO and 6 with isolated AVSA. The incidence of LHO was significantly higher among Europeans (0.59 per 1000) compared with Māori (0.31 per 1000; p<0.001) and Pacific peoples (0.27 per 1000; p=0.002). Terminations were uncommon among Māori and Pacific peoples. Total case fatality was, however, lower in Europeans compared with other ethnicities (42% vs 63%; p=0.002) due to a higher surgical intervention rate and better infant survival. The perinatal and infant mortality rate was 82% for HLHS, 15% for AAO and 2% for AVSA.

CONCLUSION

HLHS carries a high perinatal and infant mortality risk. There are ethnic differences in the incidence of and mortality from congenital LHO with differences in mortality rate suggesting inequities may exist in the perinatal management pathway.

Can Ultrasound in Early Gestation Improve Visualization of Fetal Cardiac Structures in Obese Pregnant Women?

OBJECTIVES

To determine whether ultrasound (US) imaging of obese pregnant women in early gestation improves fetal cardiac visualization.

METHODS

We report a prospective longitudinal trial comparing late first- and early second-trimester US to traditional second-trimester US for fetal cardiac screening in maternal obesity. All study participants received US for fetal cardiac screening at a gestational age of 13 weeks to 15 weeks 6 days using a transvaginal or transabdominal approach (UST1). All patients also underwent a traditional transabdominal examination at 20 to 22 weeks (UST2). If UST2 failed to complete the cardiac visualization, a follow up examination (second UST2) was performed 2 to 4 weeks later. Imaging was considered complete if the visceral situs, 4 chambers, outflow tracts, and 3 vessels were visualized. The completion rates between UST1 and UST2 were the primary outcomes. A power analysis (85%) and sample size calculation (n = 145) were performed.

RESULTS

A total of 152 pregnancies met study criteria. Completion rates of cardiac screening were 77% for UST1 and 70% for UST2 (P = .143). This comparison reached statistical significance in patients with a body mass index of greater than 40 kg/m² (UST1 [69%] versus UST2 [38%]; P = .001). Sixty-two percent of patients with a body mass index of greater than 40 kg/m² required second UST2. The highest fetal cardiac screening completion rate was achieved when UST1 was combined with UST2 (96.1%). In 1 fetus, congenital heart disease was detected at UST1 and later confirmed.

CONCLUSIONS

This study represents the largest prospective trial assessing early-gestation US for fetal cardiac screening in the setting of maternal obesity. In obese pregnancies, the addition of early-gestation US to the 20- to 22-week US substantially improves the visualization of fetal cardiac anatomy.

Detailed Fetal Anatomic Ultrasound Examination: Effect of the 2014 Consensus Report on a Tertiary Referral Center

This study evaluates the impact of extended cardiac views on examination time, repeat imaging, and anomaly detection before and after implementation of 76811 guidelines (American Institute of Ultrasound in Medicine Consensus 2014). It is a retrospective study of singleton pregnancies undergoing detailed ultrasound imaging at 18 weeks' gestation or greater before and after the protocol change in an academic, tertiary care fetal center. Views required prior to 2014: 4-chamber, left outflow tract, right outflow tract. Additional views required after 2014: bicaval, aortic arch, 3-vessel, and 3-vessel trachea. Fetuses with known anomalies were excluded. Rates of detection of congenital heart disease (CHD), examination completion, repeat examination recommendation, fetal echocardiogram recommendation, completion by body mass index, and cardiac examination time were determined. Six hundred twenty-four subjects were included, 217 before and 407 after protocol change. Views obtained were as stated in the American Institute of Ultrasound in Medicine/Society for Maternal-Fetal Medicine consensus. Detection of CHD was not improved. Examination times increased by 20% (6.4 vs 7.7 minutes, P < 0.05). Number of incomplete studies increased by 130% (11% to 26%, P < 0.05). Twice as many patients were referred for repeat examination (6% vs 13%, P < 0.05). Completion rates were negatively correlated with body mass index. Recommendations for fetal echocardiogram were unchanged (5% vs 6%, P = 0.6). Additional imaging did not increase detection rate of CHD (3% vs 2%, P = 0.3). Extended cardiac views resulted in increased examination time, more incomplete examinations, and more repeat examinations without changing detection rates of CHD.

Does transvaginal ultrasound at 13-15 weeks improve anatomic survey completion rates in obese gravidas?

Objective: Obesity increases the difficulty of completing the fetal anatomic survey. This is of added concern in obese gravidas who are at higher risk of congenital fetal anomalies. We hypothesized that incorporation of an early transvaginal assessment could improve the completion rate of the fetal anatomic survey in obese women.Methods: We performed a prospective, longitudinal, blinded study of obese gravidas (BMI ≥ 35 kg/m²) comparing the use of a single early second trimester transvaginal ultrasound in addition to midtrimester transabdominal ultrasound versus traditional serial midtrimester ultrasound alone for completion of the anatomic survey. Transvaginal ultrasound for anatomy was performed between 13 0/7 and 15 6/7 week followed by midtrimester anatomic ultrasound, with each patient serving as her own control. Structures were marked as optimally or suboptimally viewed after each ultrasound. Sonographers and reviewers were blinded to images from the transvaginal ultrasound. Completion rates and gestational age at completion were compared between groups.Results: Fifty subjects were included. Fetal anatomic survey was completed in 62% using standard midtrimester assessment versus 78% with the addition of early transvaginal assessment (p = .04). The survey was completed at an earlier gestational age utilizing the transvaginal approach (22 0/7 ± 6 3/7) compared to traditional midtrimester transabdominal ultrasound approach (25 2/7 ± 5 3/7) p < .0005.Conclusions: Incorporation of an early transvaginal assessment of anatomy in obese women improved the rate of completion and led to earlier gestational age at completion of the fetal anatomic survey. Consideration should be given to including an early transvaginal sonogram as part of routine assessment of women with a BMI ≥ 35.

Applicability of Standardized Early Fetal Heart Examination in the Obese Population

OBJECTIVE

This study aimed to evaluate the impact of obesity on early evaluation of fetal cardiac landmarks using a standardized examination method at the time of nuchal translucency scan.

METHODS

This was a cross-sectional study of an ongoing prospective cohort at high risk for congenital heart defects. We used a standardized examination protocol using 2-dimensional sonography with power Doppler in the evaluation of fetal cardiac landmarks consisting of 4-chamber view, outflow tract relationship, and transverse arches view. The study population was stratified based on maternal body mass index into nonobese (<30 kg/m² ) and obese (≥30 kg/m² ). Groups were compared in terms of satisfactory evaluation of fetal cardiac landmarks, transvaginal sonography use, and scan times required for the evaluations. Subanalysis was performed by further categorizing obesity into nonmorbid obesity (30.0-39.9 kg/m² ) and morbid obesity (≥40 kg/m² ).

RESULTS

A total of 190 patients were evaluated. Of these, 48.4% (n = 92) were obese. The most common indication for fetal cardiac assessment was maternal pregestational diabetes mellitus (42.6%). Transvaginal sonography was utilized in one nonobese woman (1.4%) and 11 obese women (12%) (P = .002). The satisfactory evaluation of 4-chamber view, outflow tract relationship, transverse arches view, and all views were not significantly different between groups (P > .05). The scan time was about 5 minutes longer in the obese group compared with nonobese group (P = .020).

CONCLUSIONS

Obesity does not hamper early evaluation of fetal cardiac landmarks around the time of nuchal translucency scan. However, obese patients are more likely to require transvaginal examinations.

Influence of maternal obesity on the accuracy of ultrasonography birth weight prediction

Objective: The aim of the study was to investigate whether the accuracy of ultrasound estimates of fetal weight (EFW) was dependent on maternal obesity.Study design: A prospective cross-sectional study of 1064 singleton pregnant women classified according to body mass index (BMI) into two categories: normal (BMI < 25 kg/m², n = 863) and obese (BMI ≥ 35 kg/m², n = 201) was conducted. EFW were calculated using Hadlock's formula, and the difference between EFW and the actual birthweight (absolute percent error) was analyzed in both groups. Spearman's correlation was used to assess the relationship between ultrasound performance (absolute error), maternal BMI, and actual birth weight.Results: Median absolute error of sonographic EFW was 5.90 and 6.47% for the normal and obese groups, respectively (p .38). A correlation between EFW and birth weight (BW) was found in both groups, r = 0.755 (p < .001) and r = 0.753 (p < .001), respectively. The correlation between absolute error, maternal BMI, and fetal birth weight was poor.Conclusions: Maternal obesity is unrelated to the accuracy of sonographic EFW, and regardless of maternal or fetal size, ultrasound is currently an accurate method of prediction for both obese and normal weight pregnant women.

Improving image quality of mid-trimester fetal sonography in obese women: role of ultrasound propagation velocity

OBJECTIVE

The quality of ultrasound images is impaired in obese patients. All ultrasound scanners are calibrated for an ultrasound propagation velocity of 1540 m/s, but the propagation in fatty tissue is slower (in the order of 1450 m/s). The main objective of this study was to evaluate the quality of images obtained with different ultrasound propagation velocity settings during the mid-trimester fetal ultrasound examination in obese patients.

METHODS

This was a cross-sectional study using image sets of four recommended scanning planes collected from 32 obese pregnant women during their mid-trimester fetal scan. Each image set comprised three images obtained successively at three different propagation velocity settings (1540 m/s, 1480 m/s and 1420 m/s). A panel of 114 experts assessed the quality of 100 image sets, grading them from A (most acceptable) to C (least acceptable). Scanning-plane-specific indicators of adiposity (fatty layer thickness, probe-to-organ distance) were analyzed for each scanning plane.

RESULTS

The experts had a mean of 18.1 ± 10.2 years of experience. The grade distribution (A, B, C) differed significantly (P < 0.0001) between the three propagation velocity settings tested; at the lower speed of 1480 m/s, images were most often graded A, while at the conventional speed of 1540 m/s, they were most often graded C. Regardless of the scanning plane, the thicker the fatty layer of the abdominal wall in a given plane, the lower the preferred speed (P < 0.0001).

CONCLUSION

The construction of images taking into account ultrasound propagation velocities lower than 1540 m/s can improve significantly the quality of images obtained during mid-trimester fetal ultrasonography in obese women. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Acceptance of a new non-invasive fetal monitoring system and attitude for telemedicine approaches in obstetrics: a case-control study

PURPOSE

Reduction of maternal morbidity and mortality is a major worldwide objective anchored in the millennium goals of the United Nations. To improve fetal and maternal care, a constant attempt to discover groundbreaking technologies is ongoing. One approach is the enhancement of non-invasive fetal ECG devices. Most importantly, acceptance of new technologies by pregnant women is a prerequisite for successful implementation.

METHODS

This questionnaire-based study conducted at the University Hospital Heidelberg, Germany between May and June 2017 evaluates pregnant women's attitudes towards a new device for fetal ECG monitoring and its potential home usage. The study population was questioned after exposure to the Parides/Atlantis prototype (Nemo Healthcare, Veldhoven, The Netherlands), whereas the maternal and gestational age-matched control group was left to envision telemedical topics.

RESULTS

The prototype and its potential usage in a clinical and telemedical setting was highly accepted, and its comfort and appearance satisfied participants. Its use caused significantly improved telemedical understanding as envision increased (p = 0.0015). Implementation and integration of telemedical devices into antenatal care was significantly preferred by the study group (p = 0.0011), though participants desire more specific features for their personal use. Optional home-based self-monitoring to reduce scheduled doctoral visits (p = 0.0004) as well as self-assessment prior to self-initiated, unscheduled consultation (p < 0.0001) could be affected positively by such a device. Furthermore, it could reduce face-to-face interaction with the care provider (p = 0.0163).

CONCLUSIONS

The positive feedback on remote self-monitoring might open options for a more "patient as partners" oriented prenatal care in the future. Safety and reliability remain a major issue. More comprehensive studies with new technologies are needed to diligently ensure quality of care. Finally, results for new technologies must be communicated to pregnant women for their acceptance and usage of new devices.

Clinical Utility of Fetal Short-Lag Spatial Coherence Imaging

In this study, we evaluate the clinical utility of fetal short-lag spatial coherence (SLSC) imaging. Previous work has documented significant improvements in image quality with fetal SLSC imaging as quantified by measurements of contrast and contrast-to-noise ratio (CNR). The objective of this study was to examine whether this improved technical efficacy is indicative of the clinical utility of SLSC imaging. Eighteen healthy volunteers in their first and second trimesters of pregnancy were scanned using a modified Siemens SC2000 clinical scanner. Raw channel data were acquired for routinely examined fetal organs and used to generate fully matched raw and post-processed harmonic B-mode and SLSC image sequences, which were subsequently optimized for dynamic range and other imaging parameters by a blinded sonographer. Optimized videos were reviewed in matched B-mode and SLSC pairs by three blinded clinicians who scored each video based on overall quality, target conspicuity and border definition. SLSC imaging was highly favored over conventional imaging with SLSC scoring equal to (28.2 ± 10.5%) or higher than (63.9 ± 12.9%) B-mode for video pairs across all examined structures and processing conditions. Multivariate modeling revealed that SLSC imaging is a significant predictor of improved image quality with p ≤ 0.002. Expert-user scores for image quality support the application of SLSC in fetal ultrasound imaging.

Screening the second-trimester fetal heart in women with an increased body mass index using three-dimensional volume sweep

PURPOSE

To determine the percentage of fetal cardiac anatomy as detailed in the International Society of Ultrasound in Obstetrics and Gynecology Practice Guidelines on sonographic screening examination of the fetal heart, which can be visualised in women with a body mass index (BMI) >30 kg/m² using three-dimensional (3D) volume sweeps.

METHODS

3D volumes of the fetal heart were taken prospectively in 40 fetuses during routine second-trimester fetal anatomy scan. Scans and 3D volume sweeps were performed by two experienced sonographers and two experienced raters interpreted the 3D data. 3D volume acquisitions and post-processing analysis were performed according to the techniques described by Weissmann-Brenner et al.

RESULTS

The two raters were able to detect an average of 12.9 and 14.1 of the 16 parameters in the 40 patients. Agreement between raters for the 16 parameters had an average of 80%. Five parameters (stomach, situs, heart occupies a third of thoracic area, majority of heart in the left chest and cardiac axis) were detected by both raters on all patients. The range of agreement was between 40% and 100%. The three-vessel view and bifurcation had agreement <60%.

CONCLUSION

Consistent identification of all views of the fetal heart was not achieved using the simple method described in women with a BMI > 30 kg/m².

Obesity in Pregnancy: Optimizing Outcomes for Mom and Baby

Obesity is common in women of childbearing age, and management of this population around the time of pregnancy involves specific challenges. Weight and medical comorbidities should be optimized both before and during pregnancy. During pregnancy, gestational weight gain should be limited, comorbidities should be appropriately screened for and managed, and fetal health should be monitored. Consideration should be given to the optimal timing of delivery and to reducing surgical and anesthetic complications. In the postpartum period, breastfeeding and weight loss should be promoted. Maternal obesity is associated with adverse metabolic effects in offspring, promoting an intergenerational cycle of obesity.

Are there risk factors for false-positive malformation diagnoses on obstetric ultrasound? A nested case-control study

INTRODUCTION

In a population-based study, we found an overall false-positive rate of 8.8% for the second and third trimester ultrasounds. Although numerous studies have been performed to examine factors which lead to false negatives, the same is not true for the factors associated with false positives. The principal objective of this study was to look for risk factors for false-positive diagnoses of fetal malformations on obstetric ultrasound scans.

MATERIAL AND METHODS

In this nested case-control study, the case infants were those whose mother had a false-positive antenatal ultrasound diagnosis of a malformation during the second or third trimester (ultrasound false-positives) and who were live - or stillborn in Auvergne in 2006-2010. The control group comprised all children who were ultrasound true-negatives in 2005 and 2007. The study included 46 cases and 184 controls, matched according to the level of the maternity unit in which they were born.

RESULTS

Most false-positive diagnoses were minor malformations. The mean term at this false-positive diagnosis was 27.7±5.4 weeks; in 46.8% of cases, the diagnosis was made during the second-trimester ultrasound. A single malformation was suspected in 95.7% of the cases. In 97.9% of cases, only one anatomical system was affected. In all, 49 malformations were identified among the 46 cases and their distribution differed according to anatomical system. The only risk factor identified was a body mass index (BMI)<25 (ORa=1.7; 95%CI: 1.2-2.4).

DISCUSSION

A maternal BMI<25 was the only risk factor identified for a false-positive ultrasound diagnosis of a fetal malformation.

Risk of major congenital malformations in relation to maternal overweight and obesity severity: cohort study of 1.2 million singletons

Objective To estimate the risks of major congenital malformations in the offspring of mothers who are underweight (body mass index (BMI) <18.5), overweight (BMI 25 to <30), or in obesity classes I (BMI 30 to <35), II (35 to <40), or III (≥40) compared with offspring of normal weight mothers (BMI 18.5 to <25) in early pregnancy.Design Population based cohort study.Setting Nationwide Swedish registries.Participants 1 243 957 liveborn singleton infants from 2001 to 2014 in Sweden. Data on maternal and pregnancy characteristics were obtained by individual record linkages.Exposure Maternal BMI at the first prenatal visit.Main outcome measures Offspring with any major congenital malformation, and subgroups of organ specific malformations diagnosed during the first year of life. Risk ratios were estimated using generalised linear models adjusted for maternal factors, sex of offspring, and birth year.Results A total of 43 550 (3.5%) offspring had any major congenital malformation, and the most common subgroup was for congenital heart defects (n=20 074; 1.6%). Compared with offspring of normal weight mothers (risk of malformations 3.4%), the proportions and adjusted risk ratios of any major congenital malformation among the offspring of mothers with higher BMI were: overweight, 3.5% and 1.05 (95% confidence interval 1.02 to 1.07); obesity class I, 3.8% and 1.12 (1.08 to 1.15), obesity class II, 4.2% and 1.23 (1.17 to 1.30), and obesity class III, 4.7% and 1.37 (1.26 to 1.49). The risks of congenital heart defects, malformations of the nervous system, and limb defects also progressively increased with BMI from overweight to obesity class III. The largest organ specific relative risks related to maternal overweight and increasing obesity were observed for malformations of the nervous system. Malformations of the genital and digestive systems were also increased in offspring of obese mothers.Conclusions Risks of any major congenital malformation and several subgroups of organ specific malformations progressively increased with maternal overweight and increasing severity of obesity. For women who are planning pregnancy, efforts should be encouraged to reduce adiposity in those with a BMI above the normal range.

The Role of Early Gestation Ultrasound in the Assessment of Fetal Anatomy in Maternal Obesity

OBJECTIVES

The 2012 Eunice Kennedy Shriver National Institute of Child Health fetal imaging consensus suggested that fetal anatomy ultrasound in obese pregnancies be performed at 20 to 22 weeks, with follow-up in 2 to 4 weeks if anatomy is incomplete. It was postulated that imaging in early gestation may improve visualization, although no prospective trials had been done to date.

METHODS

We performed a prospective longitudinal blinded trial comparing an early gestation ultrasound (13 + 0 to 15 + 6 weeks) with the traditional second-trimester ultrasound for completion of the fetal anatomy survey in obese patients. Inclusion criteria included singleton gestation, body mass index (BMI) more than 30, less than 16 + 0 weeks' gestation, and no karyotype abnormality; exclusion criteria included age younger than 18 years, more than 16 weeks' gestation at time of consent, and BMI less than 30. Participants received a transvaginal and/or transabdominal sonogram for fetal anatomic survey at 13 + 0 to 15 + 6 weeks' gestation (US1). Images from US1 were blinded to physicians and sonographers performing subsequent examinations. All participants underwent the traditional transabdominal sonogram at 18 to 24 weeks (US2). If US2 failed to complete the anatomic survey, a repeat transabdominal sonogram (2-US2) was performed 2 to 4 weeks later.

RESULTS

A total of 152 pregnancies met the criteria. Anatomy completion rate was 57.2% for US1 and 62.5% for US2, which was not statistically significant, even when stratified by BMI. Excluding the philtrum, the US1 performed better than US2 for class III obesity (65.5% versus 45.5% [P = .035]). Combination of US1 + US2 yielded a higher completion rate than US2 + 2-US2 (94.1% versus 83.6% [P = .0023]).

CONCLUSIONS

In the setting of maternal obesity, the addition of an ultrasound in early gestation may be of highest benefit for patients with class III obesity (BMI > 40 kg/m² ).

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.

Obesity epidemic: impact from preconception to postpartum

The obesity epidemic is on the rise throughout the USA and the world. Not only does it affect the general population but it also specifically poses unique threats to a woman’s life in the antepartum, peripartum and postpartum periods. An increased BMI is associated with worse perinatal outcomes, including higher rates of preeclampsia (and other hypertensive disorders), macrosomia, other neonatal morbidities and gestational diabetes. Isolated maternal obesity and additional maternal diabetes predispose the infant to potential adult disease through fetal programming. This review of the literature examines the effects of obesity on a woman’s life, outlining complications beginning with preconception through the postpartum period.

Lay abstract: The obesity epidemic poses unique threats during the whole cycle of pregnancy. This review examines the effects of obesity on a woman’s life, outlining complications from prior to conception through the postpartum period. In addition, the contributions to adult disease of fetal exposure to this maternal risk are discussed. Future advances in nanotechnology and better understanding of placental function might allow more options in preventative and therapeutic interventions, yet with minimal fetal risk.

The Performance of First-Trimester Anatomy Scan: A Decision Analysis

Introduction First-trimester ultrasound (US) for anatomy assessment may improve anomaly detection, but it may also increase overall US utilization. We sought to assess the utility of first-trimester US for evaluation of fetal anatomy. Materials and Methods A decision analytic model was created to compare first- plus second-trimester anatomy scans to second-trimester scan alone in four populations: general, normal weight women, obese women, and diabetics. Probability estimates were obtained from the literature. Outcomes considered were number of: major structural anomalies detected, US performed, and false-positive US. Multivariable sensitivity analyses were performed to evaluate the consistency of the model with varying assumptions. Results A strategy of first- plus second-trimester US detected the highest number of anomalies but required more US examinations per anomaly detected. The addition of a first-trimester anatomy US was associated with a small increase in the false-positive US (< 10/10,000). In populations with higher anomaly prevalence and lower second-trimester US sensitivity (i.e., diabetes, obesity), the number of additional US performed per anomaly detected with the first-trimester US was < 60. Discussion In high-risk populations, a first-trimester US in addition to a second-trimester US may be a beneficial approach to detecting anomalies.

Optimal visualization of the fetal four-chamber and outflow tract views with transabdominal ultrasound in the morbidly obese: Are we there yet?

BACKGROUND

To compare optimal visualization of the four-chamber and outflow-tract views of the fetal heart on sonographic examination between morbidly obese (body mass index [BMI] ≥ 40 kg/m(2) ) and nonobese (BMI < 25 kg/m(2) ) pregnant women.

METHODS

In this retrospective cohort study, we included records and images from 509 pregnant women who had first undergone sonographic examination between 18 and 36 weeks' fetal gestational age.

RESULTS

Compared with the nonobese women, morbidly obese women had lower optimal visualization of the four-chamber and outflow-tract heart views: four-chamber view, morbidly obese, 83/186 (44.6%), versus nonobese, 283/323 (87.6%), and outflow-tract view, morbidly obese, 80/186 (43%) versus nonobese, 258/290 (89%); p < 0.0001 for each comparison. Similar outcomes were observed when the results from each subcategory of morbidly obese women (ie, BMI 40-49.9, 50-59.9, and ≥60 kg/m(2) ) were compared with that from nonobese women; p < 0.0001 for each comparison. These outcomes remained the same regardless of whether this comparison was made among those who had their examination before or at 19 weeks' or more gestational age. Among the morbidly obese women, there was no difference in optimal visualization of the four-chamber or outflow-tract views regardless of whether the examination was performed at <23 weeks' or at ≥23 weeks' gestational age: four-chamber view <23 weeks, 44.8% (78/174), versus four-chamber view ≥23 weeks, 41.7% (5/12); p = 0.8, and outflow-tract view <23 weeks, 43.1% (75/174), versus outflow-tract view ≥23 weeks, 41.7% (5/12); p = 0.9. After controlling for maternal age and race, the odds of visualizing the four-chamber and outflow-tract views in the morbidly obese were reduced compared with those in their nonobese counterparts: odds ratio (OR) for four-chamber, 0.13; 95% confidence interval (CI), 0.08-0.21, and OR for outflow-tract, 0.11; 95% CI, 0.07-0.17.

CONCLUSIONS

Optimal visualization of the fetal four-chamber and outflow-tract views was achieved in less than 50% of morbidly obese women, compared with almost 90% in nonobese women.