Reducing macrosomia-related birth complications in primigravid women: ultrasound- and magnetic resonance imaging-based models.

BACKGROUND: Many complications increase with macrosomia, which is defined as birthweight of ≥4000 g. The ability to estimate when the fetus would exceed 4000 g could help to guide decisions surrounding the optimal timing of delivery. To the best of our knowledge, there is no available tool to perform this estimation independent of the currently available growth charts. OBJECTIVE: This study aimed to develop ultrasound- and magnetic resonance imaging-based models to estimate at which gestational age the birthweight would exceed 4000 g, evaluate their predictive performance, and assess the effect of each model in reducing adverse outcomes in a prospectively collected cohort. STUDY DESIGN: This study was a subgroup analysis of women who were recruited for the estimation of fetal weight by ultrasound and magnetic resonance imaging at 36 0/7 to 36 6/7 weeks of gestation. Primigravid women who were eligible for normal vaginal delivery were selected. Multiparous patients, patients with preeclampsia spectrum, patients with elective cesarean delivery, and patients with contraindications for normal vaginal delivery were excluded. Of note, 2 linear models were built for the magnetic resonance imaging- and ultrasound-based models to predict a birthweight of ≥4000 g. Moreover, 2 formulas were created to predict the gestational age at which birthweight will reach 4000 g (predicted gestational age); one was based on the magnetic resonance imaging model, and the second one was based on the ultrasound model. This study compared the adverse birth outcomes, such as intrapartum cesarean delivery, operative vaginal delivery, anal sphincter injury, postpartum hemorrhage, shoulder dystocia, brachial plexus injury, Apgar score of <7 at 5 minutes of life, neonatal intensive care unit admission, and intracranial hemorrhage in the group of patients who delivered after the predicted gestational age according to the magnetic resonance imaging-based or the ultrasound-based models with those who delivered before the predicted gestational age by each model, respectively. RESULTS: Of 2378 patients, 732 (30.8%) were eligible for inclusion in the current study. The median gestational age at birth was 39.86 weeks of gestation (interquartile range, 39.00-40.57), the median birthweight was 3340 g (interquartile range, 3080-3650), and 63 patients (8.6%) had a birthweight of ≥4000 g. Prepregnancy body mass index, geographic origin, gestational age at birth, and fetal body volume were retained for the optimal magnetic resonance imaging-based model, whereas maternal age, gestational diabetes mellitus, diabetes mellitus type 1 or 2, geographic origin, fetal gender, gestational age at birth, and estimated fetal weight were retained for the optimal ultrasound-based model. The performance of the first model was significantly better than the second model (area under the curve: 0.98 vs 0.89, respectively; P<.001). The group of patients who delivered after the predicted gestational age by the first model (n=40) had a higher risk of cesarean delivery, postpartum hemorrhage, and shoulder dystocia (adjusted odds ratio: 3.15, 4.50, and 9.67, respectively) than the group who delivered before this limit. Similarly, the group who delivered after the predicted gestational age by the second model (n=25) had a higher risk of cesarean delivery and postpartum hemorrhage (adjusted odds ratio: 5.27 and 6.74, respectively) than the group who delivered before this limit. CONCLUSION: The clinical use of magnetic resonance imaging- and ultrasound-based models, which predict a gestational age at which birthweight will exceed 4000 g, may reduce macrosomia-related adverse outcomes in a primigravid population. The magnetic resonance imaging-based model is better for the identification of the highest-risk patients.

Fetal magnetic resonance imaging at 36 weeks predicts neonatal macrosomia: the PREMACRO study.

BACKGROUND: Large-for-gestational-age fetuses are at increased risk of perinatal morbidity and mortality. Magnetic resonance imaging seems to be more accurate than ultrasound in the prediction of macrosomia; however, there is no well-powered study comparing magnetic resonance imaging with ultrasound in routine pregnancies. OBJECTIVE: This study aimed to prospectively compare estimates of fetal weight based on 2-dimensional ultrasound and magnetic resonance imaging with actual birthweights in routine pregnancies. STUDY DESIGN: From May 2016 to February 2019, women received counseling at the 36-week clinic. Written informed consent was obtained for this Ethics Committee-approved study. In this prospective, single-center, blinded study, pregnant women with singleton pregnancies between 36 0/7 and 36 6/7 weeks' gestation underwent both standard evaluation of estimated fetal weight with ultrasound according to Hadlock et al and magnetic resonance imaging according to the formula developed by Baker et al, based on the measurement of the fetal body volume. Participants and clinicians were aware of the results of the ultrasound but blinded to the magnetic resonance imaging estimates. Birthweight percentile was considered as the gold standard for the ultrasound and magnetic resonance imaging-derived percentiles. The primary outcome was the area under the receiver operating characteristic curve for the prediction of large-for-gestation-age neonates with birthweights of ≥95th percentile. Secondary outcomes included the comparative prediction of large-for-gestation-age neonates with birthweights of ≥90th, 97th, and 99th percentiles and small-for-gestational-age neonates with birthweights of ≤10th, 5th, and 3rd percentiles for gestational age and maternal and perinatal complications. RESULTS: Of 2914 women who were initially approached, results from 2378 were available for analysis. Total fetal body volume measurements were possible for all fetuses, and the time required to perform the planimetric measurements by magnetic resonance imaging was 3.0 minutes (range, 1.3-5.6). The area under the receiver operating characteristic curve for the prediction of a birthweight of ≥95th percentile was 0.985 using prenatal magnetic resonance imaging and 0.900 using ultrasound (difference=0.085, P<.001; standard error, 0.020). For a fixed false-positive rate of 5%, magnetic resonance imaging for the estimation of fetal weight detected 80.0% (71.1-87.2) of birthweight of ≥95th percentile, whereas ultrasound for the estimation of fetal weight detected 59.1% (49.0-68.5) of birthweight of ≥95th percentile. The positive predictive value was 42.6% (37.8-47.7) for the estimation of fetal weight using magnetic resonance imaging and 35.4% (30.1-41.1) for the estimation of fetal weight using ultrasound, and the negative predictive value was 99.0% (98.6-99.3) for the estimation of fetal weight using magnetic resonance imaging and 98.0% (97.6-98.4) for the estimation of fetal weight using ultrasound. For a fixed false-positive rate of 10%, magnetic resonance imaging for the estimation of fetal weight detected 92.4% (85.5-96.7) of birthweight of ≥95th percentile, whereas ultrasound for the estimation of fetal weight detected 76.2% (66.9-84.0) of birthweight of ≥95th percentile. The positive predictive value was 29.9% (27.2-32.8) for the estimation of fetal weight using magnetic resonance imaging and 26.2% (23.2-29.4) for the estimation of fetal weight using ultrasound, and the negative predictive value was 99.6 (99.2-99.8) for the estimation of fetal weight using magnetic resonance imaging and 98.8 (98.4-99.2) for the estimation of fetal weight using ultrasound. The area under the receiver operating characteristic curves for the prediction of large-for-gestational-age neonates with birthweights of ≥90th, 97th, and 99th percentiles and small-for-gestational-age neonates with birthweights of ≤10th, 5th, and 3rd percentiles was significantly larger in prenatal magnetic resonance imaging than in ultrasound (P<.05 for all). CONCLUSION: At 36 weeks' gestation, magnetic resonance imaging for the estimation of fetal weight performed significantly better than ultrasound for the estimation of fetal weight in the prediction of large-for-gestational-age neonates with birthweights of ≥95th percentile for gestational age and all other recognized cutoffs for large-for-gestational-age and small-for-gestational-age neonates (P<.05 for all).

The use of magnetic resonance imaging in the prediction of birthweight.

Extremes of fetal growth can increase adverse pregnancy outcomes, and this is equally applicable to single and multiple gestations. Traditionally, these cases have been identified using simple two-dimensional ultrasound which is quite limited by its low precision. Magnetic resonance imaging (MRI) has now been used for many years in obstetrics, mainly as an adjunct to ultrasound for congenital abnormalities and increasingly as part of the post-mortem examination. However, MRI can also be used to accurately assess fetal weight as first demonstrated by Baker et al in 1994, using body volumes rather than standard biometric measurements. This publication was followed by several others, all of which confirmed the superiority of MRI; however, despite this initial promise, the technique has never been successfully integrated into clinical practice. In this review, we provide an overview of the literature, detail the various techniques and formulas currently available, discuss the applicability to specific high-risk groups and present our vision for the future of MRI within clinical obstetrics.

Magnetic resonance imaging for prenatal estimation of birthweight in pregnancy: review of available data, techniques, and future perspectives.

Fetuses at the extremes of growth abnormalities carry a risk of perinatal morbidity and death. Their identification traditionally is done by 2-dimensional ultrasound imaging, the performance of which is not always optimal. Magnetic resonance imaging superbly depicts fetal anatomy and anomalies and has contributed largely to the evaluation of high-risk pregnancies. In 1994, magnetic resonance imaging was introduced for the estimation of fetal weight, which is done by measuring the fetal body volume and converting it through a formula to fetal weight. Approximately 10 studies have shown that magnetic resonance imaging is more accurate than 2-dimensional ultrasound imaging in the estimation of fetal weight. Yet, despite its promise, the magnetic resonance imaging technique currently is not implemented clinically. Over the last 5 years, this technique has evolved quite rapidly. Here, we review the literature data, provide details of the various measurement techniques and formulas, consider the application of the magnetic resonance imaging technique in specific populations such as patients with diabetes mellitus and twin pregnancies, and conclude with what we believe could be the future perspectives and clinical application of this challenging technique. The estimation of fetal weight by ultrasound imaging is based mainly on an algorithm that takes into account the measurement of biparietal diameter, head circumference, abdominal circumference, and femur length. The estimation of fetal weight by magnetic resonance imaging is based on one of the 2 formulas: (1) magnetic resonance imaging-the estimation of fetal weight (in kilograms)=1.031×fetal body volume (in liters)+0.12 or (2) magnetic resonance imaging-the estimation of fetal weight (in grams)=1.2083×fetal body volume (in milliliters)ˆ0.9815. Comparison of these 2 formulas for the detection of large-for-gestational age neonates showed similar performance for preterm (P=.479) and for term fetuses (P=1.000). Literature data show that the estimation of fetal weight with magnetic resonance imaging carries a mean or median relative error of 2.6 up to 3.7% when measurements were performed at <1 week from delivery; whereas for the same fetuses, the relative error at 2-dimensional ultrasound imaging varied between 6.3% and 11.4%. Further, in a series of 270 fetuses who were evaluated within 48 hours from birth and for a fixed false-positive rate of 10%, magnetic resonance imaging detected 98% of large-for-gestational age neonates (≥95th percentile for gestation) compared with 67% with ultrasound imaging estimates. For the same series, magnetic resonance imaging applied to the detection of small-for-gestational age neonates ≤10th percentile for gestation, for a fixed 10% false-positive rate, reached a detection rate of 100%, compared with only 78% for ultrasound imaging. Planimetric measurement has been 1 of the main limitations of magnetic resonance imaging for the estimation of fetal weight. Software programs that allow semiautomatic segmentation of the fetus are available from imaging manufacturers or are self-developed. We have shown that all of them perform equally well for the prediction of large-for-gestational age neonates, with the advantage of the semiautomatic methods being less time-consuming. Although many challenges remain for this technique to be generalized, a 2-step strategy after the selection of a group who are at high risk of the extremes of growth abnormalities is the most likely scenario. Results of ongoing studies are awaited (ClinicalTrials.gov Identifier # NCT02713568).

Teenage pregnancy in Belgium: protective factors in a migrant population.

BACKGROUND: Teenage pregnancies occur frequently in developing countries and are associated with social issues, including poverty, lower levels of health and educational attainment. Although frequent in European countries in the 20th century today, teenage pregnancies account for only 4% of first children. These pregnancies are usually unplanned and they are considered a vulnerability factor during the pregnancy and the postnatal period, both for the mother and the child. The purpose of our study was to evaluate the evolution of mothers and children of teenage pregnancies, several years after childbirth and to identify factors which may protect or increase the patient's vulnerability. SUBJECTS AND METHODS: We conducted a retrospective search in our patient database in order to identify all teenage pregnancies between 2010-2014 at CHU Brugmann Hospital. Outcome date data were obtained from the medical files. Mothers were contacted by phone and asked to complete our questionnaire which focused on maternal and paediatric care; and infant and child development after hospitalization. RESULTS: Out of the 342 patients identified, 84 patients were contactable and only 72 patients completed the full questionnaire. With only 4 patients originating from Belgium, our population was largely immigrant. Despite this, obstetrical, maternal and paediatric outcomes were remarkably favorable when compared to other published studies. CONCLUSION: Our study suggests that some migrant teenage mothers may have a dual advantage in terms of the wealth of a developed country in which have settled and the low social stigma related to their country of origin. More research needs to be done to further investigate this hypothesis.

Comparison of conventional 2D ultrasound to magnetic resonance imaging for prenatal estimation of birthweight in twin pregnancy.

BACKGROUND: During prenatal follow-up of twin pregnancies, accurate identification of birthweight and birthweight discordance is important to identify the high-risk group and plan perinatal care. Unfortunately, prenatal evaluation of birthweight discordance by 2-dimensional ultrasound has been far from optimal. OBJECTIVE: The objective of the study was to prospectively compare estimates of fetal weight based on 2-dimensional ultrasound (ultrasound-estimated fetal weight) and magnetic resonance imaging (magnetic resonance-estimated fetal weight) with actual birthweight in women carrying twin pregnancies. STUDY DESIGN: Written informed consent was obtained for this ethics committee-approved study. Between September 2011 and December 2015 and within 48 hours before delivery, ultrasound-estimated fetal weight and magnetic resonance-estimated fetal weight were conducted in 66 fetuses deriving from twin pregnancies at 34.3-39.0 weeks; gestation. Magnetic resonance-estimated fetal weight derived from manual measurement of fetal body volume. Comparison of magnetic resonance-estimated fetal weight and ultrasound-estimated fetal weight measurements vs birthweight was performed by calculating parameters as described by Bland and Altman. Receiver-operating characteristic curves were constructed for the prediction of small-for-gestational-age neonates using magnetic resonance-estimated fetal weight and ultrasound-estimated fetal weight. For twins 1 and 2 separately, the relative error or percentage error was calculated as follows: (birthweight - ultrasound-estimated fetal weight (or magnetic resonance-estimated fetal weight)/birthweight) × 100 (percentage). Furthermore, ultrasound-estimated fetal weight, magnetic resonance-estimated fetal weight, and birthweight discordance were calculated as 100 × (larger estimated fetal weight-smaller estimated fetal weight)/larger estimated fetal weight. The ultrasound-estimated fetal weight discordance and the birthweight discordance were correlated using linear regression analysis and Pearson's correlation coefficient. The same was done between the magnetic resonance-estimated fetal weight and birthweight discordance. To compare data, the χ2, McNemar test, Student t test, and Wilcoxon signed rank test were used as appropriate. We used the Fisher r-to-z transformation to compare correlation coefficients. RESULTS: The bias and the 95% limits of agreement of ultrasound-estimated fetal weight are 2.99 (-19.17% to 25.15%) and magnetic resonance-estimated fetal weight 0.63 (-9.41% to 10.67%). Limits of agreement were better between magnetic resonance-estimated fetal weight and actual birthweight as compared with the ultrasound-estimated fetal weight. Of the 66 newborns, 27 (40.9%) were of weight of the 10th centile or less and 21 (31.8%) of the fifth centile or less. The area under the receiver-operating characteristic curve for prediction of birthweight the 10th centile or less by prenatal ultrasound was 0.895 (P < .001; SE, 0.049), and by magnetic resonance imaging it was 0.946 (P < .001; SE, 0.024). Pairwise comparison of receiver-operating characteristic curves showed a significant difference between the areas under the receiver-operating characteristic curves (difference, 0.087, P = .049; SE, 0.044). The relative error for ultrasound-estimated fetal weight was 6.8% and by magnetic resonance-estimated fetal weight, 3.2% (P < .001). When using ultrasound-estimated fetal weight, 37.9% of fetuses (25 of 66) were estimated outside the range of ±10% of the actual birthweight, whereas this dropped to 6.1% (4 of 66) with magnetic resonance-estimated fetal weight (P < .001). The ultrasound-estimated fetal weight discordance and the birthweight discordance correlated significantly following the linear equation: ultrasound-estimated fetal weight discordance = 0.03 + 0.91 × birthweight (r = 0.75; P < .001); however, the correlation was better with magnetic resonance imaging: magnetic resonance-estimated fetal weight discordance = 0.02 + 0.81 × birthweight (r = 0.87; P < .001). CONCLUSION: In twin pregnancies, magnetic resonance-estimated fetal weight performed immediately prior to delivery is more accurate and predicts small-for-gestational-age neonates significantly better than ultrasound-estimated fetal weight. Prediction of birthweight discordance is better with magnetic resonance imaging as compared with ultrasound.

The Use of a Software-Assisted Method to Estimate Fetal Weight at and Near Term Using Magnetic Resonance Imaging.

OBJECTIVE: The aim of this study was to apply a semi-automated calculation method of fetal body volume and, thus, of magnetic resonance-estimated fetal weight (MR-EFW) prior to planned delivery and to evaluate whether the technique of measurement could be simplified while remaining accurate. METHODS: MR-EFW was calculated using a semi-automated method at 38.6 weeks of gestation in 36 patients and compared to the picture archiving and communication system (PACS). Per patient, 8 sequences were acquired with a slice thickness of 4-8 mm and an intersection gap of 0, 4, 8, 12, 16, or 20 mm. The median absolute relative errors for MR-EFW and the time of planimetric measurements were calculated for all 8 sequences and for each method (assisted vs. PACS), and the difference between the methods was calculated. RESULTS: The median delivery weight was 3,280 g. The overall median relative error for all 288 MR-EFW calculations was 2.4% using the semi-automated method and 2.2% for the PACS method. Measurements did not differ between the 8 sequences using the assisted method (p = 0.313) or the PACS (p = 0.118), while the time of planimetric measurement decreased significantly with a larger gap (p < 0.001) and in the assisted method compared to the PACS method (p < 0.01). CONCLUSION: Our simplified MR-EFW measurement showed a dramatic decrease in time of planimetric measurement without a decrease in the accuracy of weight estimates.

A Longitudinal Study on Fetal Weight Estimation at Third Trimester of Pregnancy: Comparison of Magnetic Resonance Imaging and 2-D Ultrasound Predictions.

OBJECTIVE: To prospectively compare magnetic resonance (MR) estimation of fetal weight (MR-EFW) performed at third trimester with ultrasound (US) estimation of fetal weight (US-EFW) and actual birth weight, and to evaluate factors influencing fetal growth rate near term. METHODS: US-EFW and MR-EFW were calculated at a median of 33.0 and 37.7 weeks of gestation in 37 fetuses and plotted on curve centiles to predict birth weights at 39.3 weeks of gestation. The median absolute relative errors for predicted US-EFW and MR-EFW were calculated. Regression analysis was used to investigate the effect of different variables on fetal growth rate at 35.2 weeks of gestation. RESULTS: The relative error of actual birth weight as predicted by US at 33.0 weeks was significantly higher compared with MR (7.33 vs. 4.11%; p = 0.001). This was also the case for fetal weight predicted by US at 37.7 weeks as compared with MR (6.63 vs. 2.60%; p < 0.01). Fetal growth rate was significantly and independently positively associated with the mother's weight and with gestational age at estimation (p < 0.05 for both variables). CONCLUSION: Fetal weight estimates predicted using MR at third trimester are better than those given by prenatal US. Fetal growth rate depends on fetal and maternal characteristics.

Admitting or Discharging Patients with Opiate or Alcohol Related Problems? Psychiatrist Uncertainty and Welfare Losses.

BACKGROUND: Much attention has focused on variations in therapeutic strategies across catchment areas and the related question of whether the differences in attitudes are due to socio-economic variables in the studied population or to physician uncertainty about making a specific therapeutic recommendation. SUBJECTS AND METHOD: We monitored the emergency admission rate for patients with alcohol or opiate related problems of 9 resident psychiatrists for a year. To rule out differences in population characteristics, the study took place in only one hospital: Brugmann University Hospital, whose catchment area is the north of Brussels. RESULTS: Our results show 3 distinctive practice styles. We suggest that variation in urgent admission rates for patients with alcohol and opiate related problems can be due not only to the socio-economic variables of the population, but also to medical uncertainty about the effectiveness of admission for the treatment of these disorders. CONCLUSION: The extent of uncertainty about appropriate standards of care and the plausible related inappropriate care and welfare losses are discussed.

Teenage pregnancy: a psychopathological risk for mothers and babies?

INTRODUCTION: Teen pregnancy remains a public health problem of varying importance in developing and developed countries. There are risks and consequences for teen parents and the child on the medical and socioeconomic level. METHOD: We conducted a literature search on multiple databases, focusing on the risk and the consequences of teen pregnancy and childbearing. We used different combined keywords as teen pregnancy, teen mother, teenage parents, teenage childbearing, teenage mother depression. Our search included different type of journals to have access on different views (medical, psychological, epidemiologic). RESULTS: The teen mothers are more at risk for postnatal depression, school dropout and bad socioeconomic status. The babies and children are more at risk for prematurity and low birthweight and later for developmental delays and behavior disorders. CONCLUSIONS: Pregnancy in adolescence should be supported in an interdisciplinary way (gynecologist, psychologist, child psychiatrist, midwives, pediatrician). We need further studies that allow targeting patients most at risk and personalizing maximum support.

Performance of fetal ultrasound and magnetic resonance imaging in predicting birthweight according to the test-to-delivery interval: A cohort study.

OBJECTIVE: To assess the influence of the test-to-delivery interval (TDI) on the performance of ultrasound (US) and magnetic resonance imaging (MRI) for predicting birthweight (BW). STUDY DESIGN: This is a secondary analysis of a prospective, single center, blinded cohort study that compared MRI and US for the prediction of BW ≥ 95th percentile in singleton pregnancies. Patients that were included in the initial study underwent US and MRI for estimation of fetal weight between 36 + 0/7 and 36 + 6/7 weeks of gestation (WG). The primary outcome of the current study was to report the changes of US and MRI sensitivity and specificity in the prediction of BW > 95th percentile, BW > 90th percentile, BW < 10th percentile, and BW < 5th percentile, according to the TDI. The secondary outcome was to represent the performance of both tools in the prediction of BW > 90th percentile when TDI is<2 weeks, between 2 and 4 weeks, and>4 weeks. Receiver operating characteristic (ROC) curves were constructed accordingly. RESULTS: 2378 patients were eligible for final analysis. For the prediction of BW > 95th or 90th percentile, the sensitivity of MRI remains high until 2 weeks, and it decreases slowly between 2 and 4 weeks, in contrast to the sensitivity of US which decreases rapidly 2 weeks after examination (p < 0.001). For the prediction of BW < 10th or 5th percentile, the sensitivity of both tools decreases in parallel between 1 and 2 weeks. The specificities of both tools remain high from examination till delivery. These findings are reproducible with the use of the antenatal customized and the postnatal national growth charts. CONCLUSION: The performance of MRI in the prediction of BW, especially in large-for-gestational age, is maximal when delivery occurs within two weeks of the examination, decreasing slightly thereafter, in contrast with the performance of US which decreases drastically over time.

A simulation study to assess the potential benefits of MRI-based fetal weight estimation as a second-line test for suspected macrosomia.

OBJECTIVE: To simulate the outcomes of Boulvain's trial by using magnetic resonance imaging (MRI) for estimated fetal weight (EFW) as a second-line confirmatory imaging. STUDY DESIGN: Data derived from the Boulvain's trial and the study PREMACRO (PREdict MACROsomia) were used to simulate a 1000-patient trial. Boulvain's trial compared induction of labor (IOL) to expectant management in suspected macrosomia, whereas PREMACRO study compared the performance of ultrasound-EFW (US-EFW) and MRI-EFW in the prediction of birthweight. The primary outcome was the incidence of significant shoulder dystocia (SD). Cesarean delivery (CD), hyperbilirubinemia (HB), and IOL at < 39 weeks of gestation (WG) were selected as secondary outcomes. A subgroup analysis of the Boulvain's trial was performed to estimate the incidence of the primary and secondary outcomes in the true positive and false positive groups for the two study arms. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) for the prediction of macrosomia by MRI-EFW at 36 WG were calculated, and a decision tree was constructed for each outcome. RESULTS: The PPV of US-EFW for the prediction of macrosomia in the PREMACRO trial was 56.3 %. MRI-EFW was superior to US-EFW as a predictive tool resulting in lower rates of induction for false-positive cases. Repeating Boulvain's trial using MRI-EFW as a second-line test would result in similar rates of SD (relative risk [RR]:0.36), CD (RR:0.84), and neonatal HB (RR:2.6), as in the original trial. Increasing the sensitivity and specificity of MRI-EFW resulted in a similar relative risk for SD as in Boulvain's trial, but with reduced rates of IOL < 39 WG, and improved the RR of CD in favor of IOL. We found an inverse relationship between IOL rate and incidence of SD for both US-EFW and MRI-EFW, although overall rates of IOL, CD, and neonatal HB would be lower with MRI-derived estimates of fetal weight. CONCLUSION: The superior accuracy of MRI-EFW over US-EFW for the diagnosis of macrosomia could result in lower rates of IOL without compromising the relative advantages of the intervention but fails to demonstrate a significant benefit to justify a replication of the original trial using MRI-EFW as a second-line test.

Fetal weight estimation: comparison of two-dimensional US and MR imaging assessments.

PURPOSE: To prospectively define fetal density in the second half of pregnancy by using magnetic resonance (MR) imaging and to compare estimates of fetal weight based on ultrasonography (US) and MR imaging with actual birth weight. MATERIALS AND METHODS: Written informed consent was obtained for this ethics committee-approved study. In this cross-sectional study between March 2011 and May 2012, fetal density was calculated as actual birth weight at delivery divided by fetal body volume at MR imaging in 188 fetuses between 20 weeks and 2 days and 42 weeks and 1 day of gestational age. Regression analysis was used to investigate the effect of variables, including sex, on fetal density. The US estimate of fetal weight was performed according to Hadlock et al, and the MR estimate of fetal weight was calculated based on the equation developed by Baker et al. US and MR estimates of fetal weight were compared with actual birth weights by using regression analysis. RESULTS: Median fetal density was equal to 1.04 (range, 0.95-1.18). Fetal density was significantly associated with gestational age at delivery but not with fetal sex. In 26.6% of fetuses, the US estimate of fetal weight had a relative error of more than 10%, while a similar relative error for the MR estimate of fetal weight occurred in only 1.1% of fetuses. The limits of agreement were narrower with the MR estimate of fetal weight compared with the US estimate of fetal weight. CONCLUSION: In the second half of pregnancy, fetal density varies with gestational age. Fetal weight estimates by using fetal MR imaging are better than those by using prenatal US.

The impact of different growth charts on birthweight prediction: obstetrical ultrasound vs magnetic resonance imaging.

BACKGROUND: The estimation of fetal weight by fetal magnetic resonance imaging is a simple and rapid method with a high sensitivity in predicting birthweight in comparison with ultrasound. Several national and international growth charts are currently in use, but there is substantial heterogeneity among these charts due to variations in the selected populations from which they were derived, in methodologies, and in statistical analysis of data. OBJECTIVE: This study aimed to compare the performance of magnetic resonance imaging and ultrasound for the prediction of birthweight using 3 commonly used fetal growth charts: the INTERGROWTH-21st Project, World Health Organization, and Fetal Medicine Foundation charts. STUDY DESIGN: Data derived from a prospective, single-center, blinded cohort study that compared the performance of magnetic resonance imaging and ultrasound between 36+0/7 and 36+6/7 weeks of gestation for the prediction of birthweight ≥95th percentile were reanalyzed. Estimated fetal weight was categorized as above or below the 5th, 10th, 90th, and 95th percentile according to the 3 growth charts. Birthweight was similarly categorized according to the birthweight standards of each chart. The performances of ultrasound and magnetic resonance imaging for the prediction of birthweight <5th, <10th, >90th, and >95th percentile using the different growth charts were compared. Data were analyzed with R software, version 4.1.2. The comparison of sensitivity and specificity was done using McNemar and exact binomial tests. P values <.05 were considered statistically significant. RESULTS: A total of 2378 women were eligible for final analysis. Ultrasound and magnetic resonance imaging were performed at a median gestational age of 36+3/7 weeks, delivery occurred at a median gestational age of 39+3/7 weeks, and median birthweight was 3380 g. The incidences of birthweight <5th and <10th percentiles were highest with the Fetal Medicine Foundation chart and lowest with the INTERGROWTH-21st chart, whereas the incidences of birthweight >90th and >95th percentiles were lowest with the Fetal Medicine Foundation chart and highest with the INTERGROWTH-21st chart. The sensitivity of magnetic resonance imaging with an estimated fetal weight >95th percentile in the prediction of birthweight >95th percentile was significantly higher than that of ultrasound across the 3 growth charts; however, its specificity was slightly lower than that of ultrasound. In contrast, the sensitivity of magnetic resonance imaging with an estimated fetal weight <10th percentile for predicting birthweight <10th percentile was significantly lower than that of ultrasound in the INTERGROWTH-21st and Fetal Medicine Foundation charts, whereas the specificity and positive predictive value of magnetic resonance imaging were significantly higher than those of ultrasound for all 3 charts. Findings for the prediction of birthweight >90th percentile were close to those of birthweight >95th percentile, and findings for the prediction of birthweight <5th percentile were close to those of birthweight <10th percentile. CONCLUSION: The sensitivity of magnetic resonance imaging is superior to that of ultrasound for the prediction of large for gestational age fetuses and inferior to that of ultrasound for the prediction of small for gestational age fetuses across the 3 different growth charts. The reverse is true for the specificity of magnetic resonance imaging in comparison with that of ultrasound.

Management of sickle cell disease during pregnancy: experience in a third-level hospital and future recommendations.

OBJECTIVE: To describe the outcomes of sickle-cell disease in pregnancy according to the different treatments adopted before and during pregnancy and to propose a systematic approach to treat sickle-cell disease (SCD) during pregnancy. METHODS: A retrospective descriptive study compared pregnancy outcomes among women with SCD who stopped hydroxyurea (HU) once pregnant (Group 1), were never treated before and during pregnancy (Group 2) or were treated by HU before conception who received prophylactic transfusion during pregnancy (Group 3). For each group we recorded the population's characteristics and the transfusion-related, obstetrical, perinatal and SCD complications. RESULTS: We found 11 patients for group 1 (9/11 with at least 3 painful crises during the 12 months before conception), 4 for group 2 (3/4 with no sickle-cell complications during the year before pregnancy) and 2 for group 3 (one with previous multiorgan failure (MOF), one with previous stroke). No transfusion-related complication occurred. Group 1 and 2 developed SCD complications and a high number of acute transfusions and hospital admissions. Group 3 showed none of these complications, but one patient developed preeclampsia and preterm birth. Several obstetrical and perinatal complications occurred in group 1. CONCLUSION: Not treating sickle-cell during pregnancy increases maternal and perinatal morbidity, even in mildly affected women. All sickle-cell pregnancies should be treated, according to the treatment adopted before but also to patient's SCD-history. We propose chronic transfusion to women with previous stroke or MOF or already under transfusion program, and HU for severely and mildly affected patients, respectively from the second and third trimesters. Additional prospective studies are needed to validate the results of the proposed protocol.

Protocol for the prospective observational clinical study: estimation of fetal weight by MRI to PREdict neonatal MACROsomia (PREMACRO study) and small-for-gestational age neonates.

INTRODUCTION: Macrosomia refers to growth beyond a specific threshold, regardless of gestational age. These fetuses are also frequently referred to as large for gestational age (LGA). Various cut-offs have been used but for research purposes, a cut-off above the 95th centile for birth weight is often preferred because it defines 90% of the population as normal weight. The use of centiles, rather than estimated weights, also accommodates preterm macrosomic infants, although most of the complications, maternal and fetal, arise during the delivery of large babies at term. This means that accurate identification of LGA fetuses (≥95th centile) may play an important role in guiding obstetric interventions, such as induction of labour or caesarean section. Traditionally, identification of fetuses suspected of macrosomia has been based on biometric measurements using two-dimensional (2D) ultrasound (US), yet this method is rather sub-optimal. We present a protocol (V.2.1, date 19 May 2016) for the estimation of fetal weight (EFW) by MRI to PREdict neonatal MACROsomia (PREMACRO study), which is a prospective observational clinical study designed to determine whether MRI at 36 + 0 to 36 + 6 weeks of gestation, as compared with 2D US, can improve the identification of LGA neonates ≥95th centile. METHODS AND ANALYSIS: All eligible women attending the 36-week clinic will be invited to participate in the screening study for LGA fetuses ≥95th centile and will undergo US-EFW and MRI-EFW within minutes of each other. From these estimations, a centile will be derived which will be compared with the centile of birth weight used as the gold standard. Besides birth weight, other pregnancy and neonatal outcomes will be collected and analysed. The first enrolment for the study was in May 2016. As of September 2018, 2004 women have been screened and recruited to the study. The study is due to end in April 2019. ETHICS AND DISSEMINATION: The study will be conducted in accordance with the International Conference on Harmonisation for good clinical practice and the appropriate regulatory requirement(s). A favourable ethical opinion was obtained from the Ethics Committee of the University Hospital Brugmann, reference number CE2016/44. Results will be published in peer-reviewed journals and disseminated at international conferences. TRIAL REGISTRATION NUMBER: NCT02713568.

Prenatal prediction of small-for-gestational age neonates using MR imaging: comparison with conventional 2D ultrasound.

PURPOSE: The purpose of this study is to evaluate the performance of estimating fetal weight (EFW) using magnetic resonance (MR) imaging as compared with two-dimensional (2D) ultrasound (US) in the prediction of small-for-gestational age neonates (SGA). MATERIALS AND METHODS: Written informed consent was obtained for this Ethical Committee approved study. Between March 2011 and May 2016, women with singleton pregnancies underwent US-EFW and MR-EFW within 48 h before delivery. US-EFW was based on Hadlock et al. and MR-EFW on the formula described by Backer et al. after planimetric measurement of the fetal body volume (FBV). Our outcome measure was performance in prediction of small-for-gestational age neonates by MR imaging versus US-EFW, using receiver-operating characteristic (ROC) curves. RESULTS: Two hundred and seventy women were included in the study with 18 newborns (6.7%) of birthweight ≤10th, 12 (4.5%) ≤ 5th and 7 (2.6%) ≤ 3rd centile. The area under the ROC curve for prediction of birthweight ≤10th centile by prenatal MR imaging was significantly better than by US (difference between the AUROC = 0.060, p = .01; standard error = 0.023). Similarly, the area under the ROC curve for prediction of birthweight ≤5th centile by prenatal MR imaging was significantly better than by US (difference between the AUROC = 0.019, p = .03; standard error = 0.009). Finally, there was no significant difference between the areas under the ROC curve for the prediction of birthweight ≤3rd centile between the two imaging modalities (difference between the AUROC = 0.021, p = .13; standard error = 0.014). CONCLUSION: MR-EFW performed immediately prior to delivery predicts SGA neonates significantly better than US-EFW.

Repeatability of estimated fetal weight: Comparison between MR imaging versus 2D ultrasound in at- and near-term patients.

INTRODUCTION: Our aim was to evaluate the intra- and inter-observer variability and the impact of operator experience on the estimation of fetal weight (EFW) as measured by 2-dimensional ultrasound (2D-US) and magnetic resonance (MR) imaging. MATERIAL AND METHODS: We estimated fetal weight in 46 singleton pregnancies at 35.6-41.4 weeks gestation using 2D-US according to the Hadlock formula and using MR imaging according to the equation developed by Baker. Each examination was performed twice, once by an inexperienced operator and once by an experienced operator. The MR-EFW was derived from the planimetric measurement of fetal body volume (FBV) using an assisted semi-automated method. Intra- and inter-observer variability was evaluated by Bland-Altman analysis. Regression analysis was used to investigate the effect of maternal BMI, delivery weight, diabetes and fetal gender on the differences in US-EFW between the inexperienced and experienced operators. RESULTS: US-EFW showed higher intra-observer variability than MR-EFW, irrespective of operator experience. The 95% limits of agreement of MR were narrower compared with those of the US measurements. Similarly, US-EFW showed higher inter-observer variability than MR-EFW. MR-EFW improvement over 2D-US for the limits of agreement was 77.9% for intra-observer variability and 74.5% for inter-observer variability. Regression analysis showed that the differences between US-EFW measurements were not related to any of the tested variables. CONCLUSIONS: Operator experience has a marginal impact on the variability of US-EFW and no impact on MR-EFW variability. The variability in US-EFW measurements is unpredictable.