Estimated Fetal Weight Research Articles

Fetal Health Classification and Birth Weight Estimation Using Machine Learning

Fetal Health Classification and Birth Weight Estimation Using Machine Learning

Development and validation of an ultrasound-based estimated fetal weight reference for Chinese twin pregnancy: a retrospective cohort study

BackgroundFetal growth monitoring is important for twin pregnancies. However, there has been no clinically validated tool for monitoring fetal growth of twin pregnancies in China. This study aims to develop and validate a chorionicity-specific growth chart of ultrasound estimated fetal weight (EFW) for Chinese twin pregnancies.MethodsThis retrospective cohort study included all twin pregnancies who delivered two live fetuses with gestational age ≥ 34 weeks without severe obstetric complications at a tertiary hospital from January 2007 to March 2021. The participants were divided into a development set (delivered in or before December 2017) and a validation set (delivered in or after January 2018). Chorionicity-specific growth charts were created using the generalized additive models for location, scale, and shape (GAMLSS) based on the development set. The fetuses from the validation set were classified into three groups based on the last EFW: small-for-gestational-age (SGA) indicated by both the newly established twin charts and the Hadlock singleton chart currently used for twin pregnancies in China, suspected SGA indicated by only the singleton chart, and no SGA indicated by either chart. The incidence of neonatal outcomes among the three groups was then compared accordingly, including intensive care unit (NICU) stay length, respiratory diseases, and neurological disorders.ResultsThe development set included 883 twin pregnancies and a total of 6374 EFW measurements between 16 and 38 weeks of gestation, and the validation set included 801 twin pregnancies and 7630 EFW measurements. In the development set, monochorionic diamniotic (MCDA) twins had a significantly lower EFW compared to dichorionic diamniotic (DCDA) twins beginning at 26 weeks, with the difference gradually increasing thereafter, supporting the establishment of chorionicity-specific growth charts. Of the 1,602 twin neonates in the validation set, 103 (6.4%) were classified into the SGA group, 164 (10.2%) into the suspected SGA group, and 1335 (83.3%) into the no SGA group. The incidence of respiratory diseases and neurological disorders was comparable between the suspected SGA group and the no SGA group, but apparently higher in the SGA group. Meanwhile, NICU stay lengths were consistently longer for twins in the SGA group compared to the no SGA group (difference: 0.57, 95% CI: 0.31–0.83), with no significant differences observed between the suspected SGA and no SGA groups.ConclusionsThe fetal growth trajectories differed by chorionicity, with a lower EFW for MCDA twins beginning at 26 weeks. The establishment of chorionicity-specific growth chart could reduce overdiagnosis of SGA and improve fetal growth monitoring of twin pregnancies.

Expanded Fetal Growth Restriction Definition Identifies High Proportion of Umbilical Artery Doppler Anomalies.

Fetal growth restriction (FGR) increases the risk for perinatal morbidity and mortality. The Society for Maternal-Fetal Medicine expanded the definition of FGR to independently include abdominal circumference (AC) < 10th percentile for gestational age (GA), regardless of estimated fetal weight (EFW). While studies have shown increased detection of small for GA neonates with expanded definition, no studies have evaluated the likelihood of abnormal umbilical artery Dopplers (UAD) detection with expanded definition. The objective of this study was to compare the likelihood of identifying UAD abnormalities in fetuses with normal EFW and restricted AC versus those by EFW alone. Single-institution retrospective cohort study of fetal growth ultrasounds meeting criteria for FGR either by EFW < 10th percentile or AC < 10th percentile with normal EFW. Those with FGR by AC alone were compared with those with FGR by EFW. Primary outcome was prevalence of UAD abnormalities, including elevated systolic/diastolic ratio, and absent and/or reversed end diastolic velocity. Receiver operator characteristic curves were generated to compare predictive value of UAD abnormalities by FGR definition. A total of 619 scans met criteria for FGR between November 2020 and June 2021, with 441 (71%) meeting definition by EFW and 178 (29%) by AC criteria alone. Baseline characteristics were similar between groups. FGR by AC alone was identified earlier (30.4 ± 3.3 vs. 35.4 ± 3.0 weeks' gestation, p < 0.001) with higher proportion identified before 32 weeks (70 vs. 11%, p < 0.001). Proportion of abnormal UAD were similar between groups (15 vs. 15%, adjusted odds ratio: 1.12, 95% confidence interval: 0.61-2.23). Use of EFW alone would have failed to identify 29% of abnormal UAD. A combined definition of FGR had the highest detection of abnormal UAD (area under curve: 0.78 vs. AC alone 0.73 vs. EFW alone 0.69). A definition of FGR that considers both EFW and AC improves detection of abnormal UAD. · Fetuses with restricted AC are equally likely to exhibit abnormal UAD indices compared with those that meet criteria by EFW.. · Earlier GA of FGR detection and improved detection of abnormal UAD with expanded growth definition.. · Expanded definition of FGR significantly improves detection of abnormal UAD as compared with those diagnosed with EFW criteria alone.. · Expanded growth restriction definition improves Doppler identification..

Validation of Fetal Medicine Foundation charts for fetal growth in twins: nationwide Danish cohort study.

To assess the validity of the Fetal Medicine Foundation (FMF) chorionicity-specific models for fetal growth in twin pregnancy. This was an external validation study of the FMF models using a nationwide Danish cohort of twin pregnancies. The cohort included all dichorionic (DC) and monochorionic diamniotic (MCDA) twin pregnancies with an estimated delivery date between 2008 and 2018, which satisfied the following inclusion criteria: two live fetuses at the first-trimester ultrasound scan (11-14 weeks' gestation); biometric measurements available for the calculation of estimated fetal weight (EFW) using the Hadlock-3 formula; and delivery of two liveborn infants. Validation involved assessing the distributional properties of the models and estimating the mean EFW Z-score deviations. Additionally, the models were applied to pregnancies that delivered preterm and attended non-scheduled visits (complicated pregnancies). Overall, 8542 DC and 1675 MCDA twin pregnancies met the inclusion criteria. In DC twins, 17 084 fetuses were evaluated at a total of 95 346 ultrasound scans, of which 44.5% were performed at scheduled visits in pregnancies carried to 37 + 0 weeks or later. The median number of growth scans per DC twin fetus from 20 + 0 weeks onwards was four. The model showed good agreement with the validation cohort for scheduled visits in DC twins delivered at 37 + 0 weeks or later (mean EFW Z-score, -0.14 ± 1.05). In MCDA twins, 3350 fetuses underwent 31 632 eligible ultrasound scans, of which 59.5% were performed at scheduled visits in pregnancies carried to 36 + 0 weeks or later. The median number of growth scans per MCDA twin fetus from 16 + 0 weeks onwards was 10. The model showed favorable agreement with the validation cohort for scheduled visits in MCDA twins delivered at 36 + 0 weeks or later (mean EFW Z-score, -0.09 ± 1.01). Non-scheduled visits and preterm delivery before 37 + 0 weeks for DC twins and before 36 + 0 weeks for MCDA twins corresponded with smaller weight estimates, which was consistent with the study's definition of complicated pregnancy. The FMF models provide a good fit for EFW measurements in our Danish national cohort of uncomplicated twin pregnancies assessed at routine scans. Therefore, the FMF models establish robust criteria for subsequent investigations and potential clinical applications. Future research should focus on exploring the consequences of clinical implementation, particularly regarding the identification of twins that are small-for-gestational age, as they are especially susceptible to adverse perinatal outcome. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Association of borderline fetal growth with progression to fetal growth restriction.

To evaluate if an estimated fetal weight (EFW) between the 10-15th percentiles at time of anatomy ultrasound, referred to as borderline fetal growth, is associated with progression to fetal growth restriction (FGR) on subsequent ultrasound, delivery of a SGA neonate or neonatal intensive care (NICU) admission. We performed a secondary analysis using the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be data (NuMom2b). The exposures were normotensive pregnancies with non-anomalous singleton gestations with normal growth, defined as EFW >15th percentile at the anatomy scan compared to borderline fetal growth fetuses defined as those with an EFW in the 10-15th percentile. The primary outcome was FGR at subsequent ultrasound, defined as EFW or AC <10%. The secondary outcomes were NICU admission and small for gestational age (SGA) neonate. Univariable analyses were performed comparing maternal baseline demographic and clinical characteristics. Multivariable analysis was performed for the primary outcome with variables adjusted a priori for body mass index, smoking status, race/ethnicity, insurance status, and drug use. 4883 patients met inclusion criteria with 114 in the borderline fetal growth group and 4769 in the normal growth group. There were no significant differences in maternal demographic or medical characteristics (Table 1). In adjusted multivariable analysis, patients with borderline growth had significantly higher odds of being diagnosed with FGR at their subsequent scan (aOR 6.68, CI 3.98-11.20) compared to those with normal growth. For secondary outcomes, patients with borderline fetal growth were significantly more likely to have SGA neonates (6.14% vs. 2.67%, p= 0.025). There was no difference in admissions to the NICU between groups. Diagnosis of borderline fetal growth at time of anatomy scan was associated with a significantly increased odds of progression to FGR at subsequent scan and delivery of a SGA neonate.

Vaginal delivery following induction and associated factors among laboring women at South Wollo Zone Public Hospitals of Ethiopia, 2023

Improving maternal and perinatal outcomes can be achieved by identifying factors affecting successful vaginal delivery following induction of labor, particularly in developing countries with low rates of induction. Besides this, evidence regarding the magnitude of successful vaginal delivery following induction and associated factors is limited in Ethiopia. Therefore, this study aimed to assess the magnitude of vaginal delivery following induction and associated factors among laboring women at South Wollo Zone Public Hospitals of Ethiopia, 2023. An institutional-based cross-sectional study was conducted among 385 from April 1 to June 15, 2023. A systematic random sampling method was used to select each participant. A pretested structured interviewer-administered questionnaire and checklist were used to collect data. Epi-Data version 4.6 and SPSS version 26 software were used for data entry and analysis, respectively. Multivariable binary logistic regression was used to identify associated factors and an adjusted odds ratio with a 95% confidence interval was used to identify significant variables. Model fitness was checked using the Hosmer-Lemeshow goodness of fit test. The study reported that 75.6% of participants gave vaginal delivery following induction with a 95% CI (71.00-79.80). Mid-upper arm circumstance 23–28 cm (AOR = 2.55, 95% CI: 1.19–5.47), multiparty (AOR = 3.01, 95% CI: 1.430–6.33), favorable bishop (AOR = 3.79, 95% CI: 1.74–8.26), oxytocin with cervical ripening method (AOR = 3.74, 95% CI: 1.99–7.04), and birth weight less than 4000gram (AOR = 5.40, 95% CI: 1.54–18.91) were factors significantly associated with successful vaginal delivery following induction. Therefore, obstetric caregivers should consider pre-induction assessments such as bishop score of the cervix and fetal weight estimation and improving the nutritional status of pregnant women.

Evaluation of fetal growth and birth weight in pregnancies with placenta previa with and without placenta accreta spectrum.

We evaluated fetal growth and birthweight in pregnancies with placenta previa with and without placenta accreta spectrum (PAS). We retrospectively studied pregnant patients with placenta previa with or without PAS diagnosed at 20-37weeks' gestation. Estimated fetal weight (EFW) percentile and fetal growth rate were calculated based on ultrasound at two timepoints: 20-24 and 30-34-weeks' gestation. Fetuses were small (SGA) or large for gestational age (LGA) when EFW or abdominal circumference was <10th or >90th percentile for gestational age, respectively. Fetal growth rate was estimated by subtracting EFW percentiles from the two ultrasounds. Birthweight in grams and percentiles were estimated via Anderson and INTERGROWTH-21 standards adjusted for neonatal sex. EFW percentiles, fetal growth rate, birth weight and birthweight percentiles were compared between patients with placenta previa with and without PAS. We studied 171 patients with and 146 patients without PAS. SGA rates did not differ between groups on first (PAS n=3, no-PAS n=3, p=0.8) or second ultrasound (PAS n=10, no-PAS n=8, p=0.8). LGA rates were similar between groups on first (PAS n=11, no-PAS n=9, p=0.8) and second ultrasound (PAS n=20, no-PAS n=12, p=0.6). The growth rate was higher in fetuses with PAS than placenta previa (1.22±22.3 vs.-4.1±18.1, p=0.07), but not significantly. The birthweight percentile was higher in the PAS than the placenta previa group (74 vs. 67, p=0.01). On multi-linear regression, birthweight percentile remained higher in the PAS group, but not significantly. Placenta previa with or without PAS is not associated with SGA, LGA or lower birthweight.

Neonatal birthweight prediction using two- and three-dimensional estimated fetal weight among borderline small fetuses.

This study aimed (1) to determine the degree of correlation between 2D and 3D estimated fetal weight (EFW) and neonatal birth weight (BW) among borderline small fetuses and (2) to compare the accuracy and precision of 2D and 3D EFW in BW prediction. A retrospective cohort study evaluated fetuses who had an ultrasound performed between January 2017 and September 2021 at a tertiary maternal center. All singleton pregnancies with 3D EFW within 4 weeks of delivery were included. Fetuses with known structural or genetic abnormalities were excluded. Pearson's correlation coefficients were determined for both 2D and 3D EFW to BW then compared using Williams' test and Fisher r to z transformation, where applicable. Mean percent difference and standard deviation were used to assess the accuracy and precision, respectively, of 2D and 3D EFWs in BW prediction. Two hundred forty-eight pregnancies were included. Ultrasound studies were performed with a median interval of 2 weeks (IQR 1, 3) between ultrasound and delivery. Both 2D and 3D estimated fetal weights showed a significant correlation with birth weight (r = 0.74 and r = 0.73, respectively), indicating similar accuracy between the two techniques. Two-dimensional and three-dimensional EFWs performed similarly in the prediction of BW in borderline small fetuses.

A Comparative Study of Fetal Weight Estimation by Symphysiofundal Height and Ultrasound Biometry in Women at Term

A Comparative Study of Fetal Weight Estimation by Symphysiofundal Height and Ultrasound Biometry in Women at Term

Accurate birth weight prediction from fetal biometry using the Gompertz model

ObjectivesMonitoring of fetal growth and estimation of birth weight is of clinical importance. During pregnancy, ultrasound fetal biometry values including femur length, head circumference, abdominal circumference, biparietal diameter are measured and used to place fetuses on “growth charts”. There is no simple growth-model-based, predictive formula in use for fetal biometry. Estimation of fetal weight at birth currently depends on ultrasound data taken a short time before birth. Study designOur cohort (“Seethapathy cohort”) consists of ultrasound biometry measurements and other data for 774 pregnant women in Chennai, India, 2015–2017. We use the Gompertz model, a standard model for constrained growth, with just three intuitive parameters, to model the growth of fetal biometry, and a machine learning (ML) model trained on these parameters to predict birth weight (BW). ResultsThe Gompertz model convincingly fits the growth of fetal biometry values. Two Gompertz parameters—t0 (inflection time) and c (rate of decrease of growth rate)—seem universal to all fetuses, while the third, A, is an overall scale specific to each fetus, capturing individual variation. On the Seethapathy cohort we can infer A for each fetus from ultrasound data available by the 24 or 35 weeks. Our ML model predicts birth weight with < 8 % error, outperforming published methods that have access to late-term ultrasound data. The same model gives an 8.4 % error in BW prediction on an independent validation cohort of 365 women. ConclusionsThe Gompertz model fits fetal biometry growth and enables birth weight estimation without need of late-term ultrasounds. Aside from its clinical predictive value, we suggest its use for future growth standards, with almost all variation described by a single scale parameter A.

Analysis of Fetal Growth and Pregnancy Outcome in Pregnant Women Infected with Novel Coronavirus in Mid-Pregnancy.

To investigate whether fetal prenatal ultrasound, fetal growth rate, and pregnancy outcome statistically differ between women infected with novel coronavirus (COVID-19) in mid-pregnancy and an uninfected control group. A retrospective analysis of biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), femur length (FL), and z-scores for each among 46 pregnant women diagnosed with COVID-19 in mid-pregnancy between December 01, 2022 and June 31, 2023 was conducted. A control group included 92 pregnant women negative for COVID-19 during the same period and was also analyzed. To examine fetal growth, rate of increase in BPD, HC, AC, FL, and estimated fetal weight (EFW) between second and third trimester scans were analyzed. In addition, pregnancy outcome, maternal comorbidities, and neonatal prognosis were assessed. The occurrence of gestational diabetes differed significantly between groups, but the fetal growth rate and EFW did not. Similarly, pregnancy outcomes and neonatal prognoses did not differ significantly between groups. Gestational diabetes was a complication that differed between patients with and without COVID-19 in this study. COVID-19 in pregnant women did not affect fetal development. Therefore, these preliminary data suggest that increased fetal monitoring is not necessary for women infected with COVID-19 during the second trimester, and these women should be reassured of the low risk of adverse fetal outcomes.

Timing of induction of labor in suspected macrosomia: retrospective cohort study, systematic review and meta-analysis.

Large-for-gestational age (LGA) is associated with several adverse maternal and neonatal outcomes. Although many studies have found that early induction of labor (IOL) in case of a LGA fetus reduces the incidence of shoulder dystocia, no current guidelines recommend this particular clinical strategy, owing to concerns about increased rates of Cesarean delivery (CD) and neonatal complications. The purpose of this study was to assess whether the timing of IOL in LGA fetuses affected maternal and neonatal outcomes in a single center, and to combine these results with evidence reported in the literature. This study comprised two parts. The first part was a retrospective cohort study that included consecutive patients with a singleton pregnancy and an estimated fetal weight ≥ 90th percentile on ultrasound between 35 + 0 and 39 + 0 weeks' gestation, who were eligible for normal vaginal delivery. The second part of the study was a systematic review of the literature and meta-analysis, including the results of our cohort study as well as those of previous studies that compared IOL with expectant management in patients with a LGA fetus. The perinatal outcomes of the study were CD, operative vaginal delivery, shoulder dystocia, brachial plexus palsy, anal sphincter injury, postpartum hemorrhage, Apgar score, umbilical artery pH, admission to the neonatal intensive care unit, use of continuous positive airway pressure, intracranial hemorrhage, need for phototherapy and bone fracture. Of the 547 patients included in this retrospective cohort study, 329 (60.1%) underwent IOL and 218 (39.9%) experienced spontaneous labor. Following covariate balancing, the odds of CD were significantly higher in the IOL group compared with the spontaneous-labor group. This difference only became apparent beyond 40 weeks' gestation (hazard ratio, 1.90; P = 0.030). The difference between the IOL and spontaneous-labor groups for the rate of shoulder dystocia was not statistically significant (hazard ratio, 1.57; P = 0.200). Seventeen studies, in addition to our own results, were included in the systematic review and meta-analysis, giving a total population of 111 300 participants. Although there was no significant difference in the rate of CD between IOL and expectant management after pooling the results of included studies, the risk for shoulder dystocia was significantly lower in the IOL group (odds ratio (OR), 0.64 (95% CI, 0.42-0.98); I2 = 19% from 12 studies) when considering only IOL performed before 40 + 0 weeks. When the studies in which IOL was carried out exclusively before 40 + 0 weeks were removed from the analysis, the risk for CD in the remaining studies was significantly higher in the IOL group (OR, 1.46 (95% CI, 1.02-2.09); I2 = 56%). There were no statistically significant differences between the IOL and expectant-management groups for the remaining perinatal outcomes. Nulliparity, history of CD and low Bishop score, but not method of induction, were independent risk factors for intrapartum CD in patients that underwent IOL for LGA. The timing of IOL in patients with suspected macrosomia significantly impacts on perinatal adverse outcomes. IOL has no impact on rates of shoulder dystocia but increases the odds of CD when considered irrespective of gestational age; in contrast, IOL may decrease the risk of shoulder dystocia without increasing the risk of other adverse maternal outcomes, in particular CD, when performed before 40 + 0 weeks (GRADE: low/very low). © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

A prospective blinded diagnostic accuracy study to assess the accuracy of fetal weight estimation at term by clinical method using Leopold’s maneuvers and ultrasonography in predicting the actual birth weight

ABSTRACT Context: Over-medicalization of normal pregnancy is associated with unnecessary inductions of labor leading to operative deliveries. In a busy outpatient department (OPD) or low-resource setup where ultrasound availability, experience, and cost will be a concern, routine ultrasound at term can be avoided if the clinical estimation of fetal weight is more or less equal to the actual birth weight. Aims: To assess the reliability and validity of fetal weight estimation at term by ultrasound and clinical estimation. Settings and Design: A prospective study of diagnostic accuracy was done over a period of 1.5 years in a tertiary hospital, which included 100 women with term singleton pregnancies admitted in obstetric wards or labor room. Methods and Material: To find out the agreement between actual birthweight and ultrasound fetal weight interclass correlation coefficient (ICC) was used. Mean difference plots (Bland–Altman plots) were done. The mean percentage error was compared with the consultant estimate and registrar estimate across groups. The sensitivity, specificity, and predictive values by clinical and ultrasound estimate were calculated for actual birth weight ≤ 2.5 kg. Results: Both methods of fetal weight estimation have moderate reliability in predicting the actual birth weight. The sensitivity of identifying birthweight &lt; 2.5 kg babies by ultrasound was slightly higher. For birth weight less than 2.5 kg, there was an overestimation of fetal weight by clinical estimation done by postgraduate with mean percentage error being statistically significant as compared with ultrasound estimation. Conclusions: In a developing country like ours where ultrasound is not readily available in all healthcare setups, the clinical method is an easy, cost-effective, simple one that can be used by all medical professionals after adequate training.

Correlation of sonographically measured fetal abdominal wall thickness with birth weight in diabetes

ObjectiveTo determine the association between sonographically measured abdominal wall thickness (AWT) and birth weight of fetuses of pregnant women with diabetes. MethodsThis retrospective study included 185 pregnant women who presented to a level I perinatal centre between January 2021 and December 2022. All mothers had diabetes, and were divided into the following subgroups: diet-controlled gestational diabetes mellitus; insulin-dependent gestational diabetes mellitus; type 1 diabetes mellitus; and type 2 diabetes mellitus. At the time of admission, gestational age varied between 29 + 2 and 41 + 2 weeks (+days) of gestation. Weight estimation was performed routinely using the Hadlock I formula. Fetal AWT was determined retrospectively at the same axial level as used for the measurement of abdominal circumference. Only women with a sonographic fetal weight estimation within 5 days before delivery were included. ResultsFor the whole cohort, a moderate positive correlation was found between fetal AWT and estimated fetal weight (r = 0.411, p < 0.001), a moderate correlation was found between fetal AWT and birth weight (r = 0.493, p < 0.001), a weak correlation was found between fetal AWT and body length (r = 0.365, p < 0.001), and a weak correlation was found between fetal AWT and body length percentile (r = 0.276, p < 0.001). No strong differences in parameters were found between the diabetes subgroups. Receiver operating characteristic (ROC) curve analysis was performed to identify newborns with birth weight > 4000 g (macrosomia) and birth weight > 90th percentile according to Voigt in the group with gestational age > 37 weeks. ROC curve analysis was performed to identify newborns with birth weight > 90th percentile in the whole cohort. AWT and sonographically estimated fetal weight were included in the calculation. The combination of AWT and estimated fetal weight only led to a marginal improvement compared with estimated fetal weight alone for predicting newborns with birth weight > 4000 g in the group with gestational age > 37 weeks [area under the curve (AUC) 0.857 vs 0.871], and for predicting newborns with birth weight > 90th percentile in the group with gestational age > 37 weeks (AUC 0.840 vs 0.846) and in the whole cohort (AUC 0.816 vs 0.826). ConclusionA sonographically measured AWT of 7.1 mm in fetuses of diabetic mothers is predictive of birth weight > 90th percentile with sensitivity of 61 %, specificity of 85 %, and AUC of 0.748. ROC curve analysis showed that estimated fetal weight determined by ultrasound (using Hadlock formula I) seems to be slightly superior for the identification of macrosomic fetuses with birth weight > 90th percentile. A threshold value for estimated fetal weight of 3774 g had sensitivity of 70 %, specificity of 86 %, and AUC of 0.816. The combination of AWT and estimated fetal weight in a single formula only yielded a marginal improvement in accuracy compared with the use of estimated fetal weight alone.

Specific growth velocity reference charts for monochorionic twin pregnancies.

We aimed to create specific growth velocity reference charts for monochorionic (MC) twin pregnancies and provide additional information for assessing fetal growth in MC twins. This retrospective study collected data from uncomplicated MC twins with serial ultrasound parameters. The four ultrasound parameters, including biparietal diameter, femur length, head circumference, and abdominal circumference, were used to calculate the estimated fetal weight (EFW). Multilevel linear regression models were applied to fit growth velocity charts for each biometric parameter and EFW. Analysis of variance was used to examine differences in birthweight by whether EFW velocity and EFW values were <10th or ≥10th percentiles. The final analysis encompassed a total of 5956 ultrasound examinations conducted on 487 MC twins. The growth velocity of four biparietal diameters exhibited a gradual decrease in a nearly linear fashion progressing from 18 to 37 gestational weeks. The EFW velocity increased steadily from 18 to 36 gestational weeks, reaching a peak of 178.2 g/week, and then the velocity gradually decreased until delivery. At 32 weeks for illustration, the lightest birth weight was observed when both EFW and EFW velocity were <10th percentile (1899 g). The study also found that birth weight was higher when EFW velocity was ≥10th percentile compared with <10th percentile, regardless of EFW being below or above the 10th percentile (2263 and 1906 g, respectively; P < 0.001). We developed specific growth velocity reference charts for MC twins, which could provide a valuable reference point for a more precise evaluation of fetal growth in MC twins. Preliminary findings indicate that the inclusion of fetal growth velocity in monitoring fetal growth provides additional information beyond EFW alone.

Application en routine des résultats d’un essai randomisé : performance de l’échographie en pratique courante pour le dépistage de la macrosomie fœtale

ObjectiveTo evaluate the performance of ultrasound at 36 weeks of gestation for screening fetal macrosomia according to the criteria of the randomized “DAME” trial. MethodRetrospective observational study over 2 years in a type 3 maternity hospital. The primary outcome was birth weight above the 97th percentile on Audipog birth weight curves. The sensitivity, specificity, positive and negative predictive value of ultrasound at 36 SA for predicting macrosomia were calculated. For each patient, the absolute value of the difference between actual and estimated weight [EPF difference=(Birth weight − Estimated weight)/Birth weight] was calculated. Among undetected macrosomic newborns (≥97th Audipog percentile), risk factors associated with misdiagnosis were investigated (false negatives versus true positives). ResultsUltrasound estimation of fetal weight at 36 SA to detect fetal macrosomia had a sensitivity of 43.7% and a specificity of 82.1%. With a positive predictive value for ultrasound of 36,9% and a negative predictive value of 85.8%. The mean absolute value of the difference between estimated and actual birth weight was 287g (95% CI [115–409]), with a mean relative difference of 6.8% (95% CI [3.0–11.3]). A relative difference of less than 10% between the estimated weight and the birth weight was found in 68.5% of the patients. Among macrosomic newborns (≥97th percentile), a third-trimester estimated fetal weight at or above the 90th percentile, along with a history of fetal macrosomia in a previous pregnancy, reduced the risk of false negatives in the screening ultrasound at 36 weeks of gestation. ConclusionUltrasound performed at 36 weeks’ gestation in a population targeted for suspected fetal macrosomia in routine practice has moderate sensitivity and positive predictive value. It would be timely for teams also applying this protocol to share their results, in order to verify whether or not our findings can be generalized to a larger scale.

Accuracy of supervised measurement of fetal weight in a residency program.

To evaluate the accuracy of ultrasound estimates of fetal weight made by residents. A cross-sectional study was conducted on consecutive pregnancies attended in an obstetric ward. All participants provided their consent to participate. Inclusion criteria were singleton pregnancies with ultrasound evaluation and delivery within 14 days. Congenital abnormalities and stillbirths were excluded. Ultrasound scans were performed by two residents, one observer per subject, following standardized methodology and supervised by senior staff. Fetal weight was calculated using the four-parameter Hadlock 1985 formula. Birth weight was measured using a standard clinical scale. Bland-Altman and mixed-effects analyses were performed. In a 6-month period, 95 gestations were recruited at 30-41 weeks, and birth weights ranged from 1200 to 4080 g. The bias between methods was -28 g (CI95%, -74 to 18) with 95% limits of agreement of ±440 g. The 95% deviation between methods was of ±16%. Parity had the most significant effect on the bias between methods; operator and maternal weight had no significant effect. Supervised measurement of fetal weight by residents demonstrated high accuracy. Parity bias may be associated with visceral fat deposition independent of maternal weight gain. A methodology for medical evaluation is presented.

Evaluation of sonographic and clinical measures in early versus late third trimester for birth weight prediction.

To evaluate the optimal timing for fetal weight estimation during the third trimester. This retrospective cohort study involved fetal weight estimations from both early (28+0-36+6 weeks) and late (37+0 weeks and beyond) third trimester. These estimations were converted to predicted birth weights using the gestation-adjusted projection formula. Birth weight predictions were compared with actual birth weights, to identify the most effective timing for weight prediction. The study included 3549 cases, revealing mean percentage errors (MPE) of -3.69% for early sonographic assessments, -2.5% for late sonographic assessments, and -1.9% for late clinical assessments. A significant difference was found between early and late sonographic estimations (P < 0.001), whereas late sonographic and clinical assessments did not differ significantly (P = 0.771). Weight predictions for fetuses below the 10th and above the 90th centiles were less accurate than for those within the 10th-90th centiles (P < 0.001). In women with obesity, late clinical estimations were less precise (MPE of -5.85) compared with non-obese women (MPE of -1.66, P < 0.001). For women with diabetes, early sonographic estimations were more accurate (MPE of -1.31) compared with non-diabetic patients (MPE of -3.94, P < 0.001) though this difference did not persist later in pregnancy. Sonographic and clinical weight predictions in the late third trimester were more accurate than earlier third-trimester sonographic assessments, hence continuous follow up and assessments closer to term are important. In women with diabetes, no adjustments in weight prediction methods are necessary. Accurately predicting birth weights for abnormally small or large fetuses remains challenging, indicating the need for improved screening and diagnostic strategies.

Comparison of Ultrasound Findings Associated with Adverse Fetal, Obstetric, and Neonatal Outcomes in Pregestational Type 1 And Type 2 Diabetes: A Systematic Review.

We aimed to summarize the available evidence examining the association between prenatal ultrasound findings and adverse fetal, obstetric, and neonatal outcomes in pregnancies complicated by type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) and to evaluate whether the predictive value of ultrasound findings for adverse outcomes varies between T1DM and T2DM pregnancies. We conducted a systematic review of the existing literature through August 12, 2024. We included articles in English that reported associations between ultrasound findings and fetal, obstetric, and neonatal outcomes in pregnant people with T1DM and T2DM. Two independent reviewers examined articles at the abstract level and, if eligible, at the full-text level; disagreements were adjudicated by a third reviewer. Of the 2,088 unique citations reviewed, 12 studies met the inclusion criteria describing associations between ultrasound findings and fetal, obstetric, and neonatal outcomes among a total of 1,165 pregnant people with T1DM and 489 pregnant people with T2DM. Most studies (10/12) examined the association between ultrasound measures of growth, including estimated fetal weight (EFW) and its individual components, abdominal wall thickness, head circumference to abdominal circumference (HC/AC) ratio, and birthweight, large for gestational age (LGA) or small for gestational age (SGA). Studies did not examine stillbirth, neonatal demise, or maternal outcomes other than cesarean section. This systematic review synthesizes the available literature on ultrasound risk markers of adverse fetal, obstetric, and neonatal outcomes separately in pregnant people with T1DM and T2DM. We identified very few studies that distinguished between pregnant people with T1DM and T2DM, and the majority focused on surrogate outcomes (e.g., LGA, SGA) of morbidity. Our findings highlight the need for further studies investigating these distinct diseases to provide evidence for antenatal management recommendations.

Does decreased fetal growth estimation in the appropriate for gestational age range affect delivery outcomes?

To study the effect of decreased estimated fetal weight (EFW) percentiles in appropriate for gestational age fetuses. This retrospective cohort study included women who had second and third trimester ultrasound examinations. Delivery and neonatal outcomes of pregnancies with decreased EFW of ≥ 30 percentiles in EFW between ultrasound examinations (decreased growth group) and those without such a decrease (control group) were compared. Deliveries with EFW or birthweight below the 10th percentile were excluded. Among 1610 deliveries, 57 were in the decreased growth group and 1553 in the control group. Maternal characteristics did not differ between the groups except for higher rate of nulliparity in the decreased growth group. We found similar rates of Category II/III monitoring, cesarean deliveries due to non-reassuring fetal heart rate and adverse neonatal outcomes. Neonatal birthweight was lower in the decreased growth group as compared to controls. This study did not find association between the group of appropriate for gestational age fetuses with decreased growth, with adverse outcomes.