Large fetal size in early pregnancy associated with macrosomia

Diagnostic Accuracy of Fetal Anterior Abdominal Wall Thickness as an Early Sonographic Sign for Diagnosing Gestational Diabetes

Introduction  Traditionally, different fetal variable measurements are used in ultrasound to assess fetal growth. Ultrasound can detect abnormal fetal growth. Gestational diabetes mellitus (GDM) is linked to higher fetal obesity as early as 20 weeks of pregnancy. The amount of fetal adipose tissue may be measured by measuring the thickness of the anterior abdominal wall. Measuring the thickness of the fetus's anterior abdominal wall (AAWT) is a straightforward procedure that may be performed alongside standard abdominal circumference measurements. Objectives  To check the diagnostic accuracy of fetal AAWT as an early sonographic sign for diagnosing GDM, keeping oral glucose tolerance test as the gold standard. Study design  This research was conducted using a cross-sectional analysis. Study place and duration The study was conducted in the Radiology Department at Rawalpindi Medical University and Allied Hospitals from July 10, 2019 to January 9, 2020. Materials and methods  Women between the ages of 18 and 45 who had a family history of type 2 diabetes and were at risk for developing GDM were recruited. Exclusions were made for diabetic women, those carrying multiples, and those with autoimmune diseases. The AAWT measurement of the fetus, which included the skin and subcutaneous tissue, was acquired using the traditional anterior cranial view, 2-3 cm lateral to cord insertion. Pregnant patients at risk for GDM underwent screening using an oral glucose tolerance test. Those exhibiting any two abnormal values were diagnosed with GDM. Results  The overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of fetal AAWT as an early sonographic sign for diagnosing GDM, with the oral glucose tolerance test as the gold standard, were 93.14%, 82.65%, 84.82%, 92.05%, and 88.0%, respectively. Conclusion  The study concludes that the diagnostic accuracy of fetal AAWT as an early sonographic indicator for identifying gestational diabetes is notably high.

Mid-Trimester Fetal Anterior Abdominal Wall Subcutaneous Tissue Thickness: An Early Ultrasonographic Predictor of Gestational Diabetes Mellitus

Background This study aimed to determine whether mid-trimester fetal anterior abdominal wall subcutaneous tissue thickness (FASTT) is an early sonographic predictor of gestational diabetes mellitus (GDM), as well as to study its correlation with maternal glycemic values on GDM screening at 24-28 weeks. Methodology We conducted a prospective, case-control study. FASTT was assessed at anomaly scan in 896 uncomplicated singleton pregnancies. The 75-gram oral glucose tolerance test (OGTT) was done for all included patients at 24-28 weeks. Women diagnosed with GDM were taken as cases and appropriately matched in equal numbers as controls. Statistical analysis was done using SPSS version 20 (IBM Corp., Armonk, NY, USA). Independent-samples t-test, chi-square test, receiver operating characteristic curve, and Pearson's correlation coefficient (r) were performed wherever applicable. Results A total of 93 cases and 94 controls were included. Fetuses of women with GDM had significantly higher mean FASTT at 20 weeks (1.605 ± 0.328 mm vs. 1.222 ± 0.121 mm; p < 0.001). The FASTT cut-off obtained was 1.35 mm (sensitivity = 79.6%, specificity = 87.2%, positive predictive value = 86%, negative predictive value = 81.2%). There was a moderate positive correlation between fasting blood sugar (FBS) and two-hour OGTT values and FASTT (r = 0.332, p < 0.001 and r = 0.399, p < 0.001, respectively). FASTT >1.35 mm had an independent predictive value for GDM and was associated with a 19.608-fold increased risk of GDM. Conclusions FASTT values greater than 1.35 mm at 20 weeks are associated with a significantly increased risk of GDM. In addition, FASTT correlates with FBS and two-hour OGTT at 24-28 weeks and is a simple predictor of GDM at 18-20 weeks.

Is there a relationship between high birth weight and umbilical vein diameter?

OBJECTIVE

The aim of the study was to evaluate the associations between sonographical measurements of the umbilical cord and birth weight in 20-24 weeks of gestations.

METHODS

This cross-sectional study was conducted with the participation of 220 low-risk pregnant women between 20-24 gestational weeks. Biparietal diameter, head and abdominal circumference, and femur length were measured for anthropometric calculations. Umbilical cord including umbilical vein diameters, placental thickness, umbilical artery. Doppler measurements (RI, PI) were recorded.

RESULTS

In accordance with the results of statistical computations, an inverse relationship was found between umbilical vein diameter and birth weight of a large gestational age (LGA) newborn in 20-24 gestational weeks (p < .05). There was no significant relationship between other parameters and birth weight of LGA newborns.

CONCLUSION

There is an inverse relationship between birth weights of newborns with LGA and umbilical vein diamater at 20-24 weeks of pregnancy. The umbilical vein diameter in the second trimester may be a promising measurement on predicting LGA fetus. The researches have not confirmed the physiopathology of this finding yet, but it is paving the path for future studies.

Individualized fetal growth assessment: critical evaluation of key concepts in the specification of third trimester size trajectories

OBJECTIVES

To characterize second and third trimester fetal growth using Individualized Growth Assessment methods in a larger cohort of fetuses with normal neonatal growth outcomes.

METHODS

A prospective longitudinal study of 119 pregnancies was performed from 18 weeks, MA, to delivery. Measurements of several 1D and 3D fetal size parameters were obtained from 3D volume data sets at 3-4 week intervals. Regression analyses were used to determine Start Points (SP) and Rossavik model (P = c {t} (k + st)) coefficients c. k and s for each parameter in each fetus. Second trimester growth velocity reference ranges were determined and size model specification functions re-established, the latter used to generate individual size models. Actual measurements were compared to predicted third trimester size trajectories using Percent Deviations. New age-specific reference ranges for the Percent Deviations of each parameter were defined using 2-level statistical modeling.

RESULTS

Rossavik models fit the data for all parameters very well (R(2): 99%), with SP's and k values similar to those found in much smaller cohorts. The c* values were strongly related to the second trimester slope (R(2): 97%), as was predicted s* to estimated c* (R(2): 54--95%). Rossavik models predicted third trimester growth with systematic errors close to 0%; random errors (95% range) ranged between 5.7 and 10.9% and 20.0 and 24.3% for 1D and 3D parameters, respectively.

CONCLUSIONS

IGA procedures for evaluating second and third trimester growth are now established based on a larger cohort (4-6 fold larger). New, more rigorously defined, age-specific standards for the evaluation of third trimester size deviations are now available for nine anatomical parameters and a weight estimation procedure that incorporates a soft tissue parameter (fractional thigh volume). These results provide a means for more reliably assessing fetal growth on an individualized basis, thus minimizing the effect of biological differences in growth.

Crown-rump length measured in the early first trimester as a predictor of low birth weight

The aim of this study is to assess the association between crown-rump length (CRL) measured before the 10th gestational week and birth weight. Results from 316 transvaginal ultrasonography scans at the 46th, 53rd, 60th, 67th, and 74th days of pregnancy were compared in low birth weight (LBW) versus normal birth weight groups. A positive correlation between CRL and birth weight was observed when CRL was measured at days 60, 67, and 74. CRL measured on the 67th day of pregnancy was significantly smaller in the LBW group than in the normal birth weight group. A cut-off value of CRL=26.5 mm measured at day 67 has the highest power to predict LBW.

A prospective observational study of early fetal growth velocity and its association with birth weight, gestational age at delivery, preeclampsia, and perinatal mortality

OBJECTIVES

We aimed to measure early fetal growth velocity and to correlate this with the birth weight, gestational age at delivery, and with the incidence of adverse pregnancy outcomes specifically preeclampsia and perinatal mortality.

METHODS

A data based prospective observational study, wherein sonographic biometry data and specific pregnancy outcome related data were collected from pregnant women's records, starting soon after their first antenatal visit. Early fetal growth velocity was measured using BPD growth between 11 and 14 weeks scan and anomaly scan and standardizing this by Z scoring.

RESULTS

Out of 607 fetuses, 41 (6.7%) were slow growing, 531 (87.4%) normally growing, and 35 (5.7%) fast growing (Z scoring <10th(,) 10-90th, and >90th percentiles respectively). As fetal growth velocity increased, the mean birth weight decreased from 2958.7±388.9 (<10th centile), 2742.1±576.6 (10-90th centile), to 2339.3±729.4 (>90th centile); and gestational age at delivery decreased from 38.5±1.3 (<10th centile), 37.5±2.1 (10-90th centile), to 36.4±2.2 (>90th centile), and both these trends were statistically significant (p<0.001).Faster growing fetuses had a higher risk of preterm delivery(spontaneous+indicated) compared to other 2 groups [OR 4.42 (2.18,8.98)], and slower growing fetuses had a higher risk of postdated deliveries compared to other 2 groups [OR 3.042 (1.44, 6.45)].We found no significant association between early fetal growth velocity and incidence of small for gestational age at birth/low birth weight at term, preeclampsia, and perinatal mortality.

CONCLUSIONS

Early fetal growth velocity between first and second trimesters, may be one of the important factors influencing ultimate birthweight and gestational age at delivery.

Fetal growth: a review of terms, concepts and issues relevant to obstetrics

The perinatal literature includes several potentially confusing and controversial terms and concepts related to fetal size and growth. This article discusses fetal growth from an obstetric perspective and addresses various issues including the physiologic mechanisms that determine fetal growth trajectories, known risk factors for abnormal fetal growth, diagnostic and prognostic issues related to restricted and excessive growth and temporal trends in fetal growth. Also addressed are distinctions between fetal growth 'standards' and fetal growth 'references', and between fetal growth charts based on estimated fetal weight vs those based on birth weight. Other concepts discussed include the incidence of fetal growth restriction in pregnancy (does the frequency of fetal growth restriction increase or decrease with increasing gestation?), the obstetric implications of studies showing associations between fetal growth and adult chronic illnesses (such as coronary heart disease) and the need for customizing fetal growth standards.

First trimester 3D volumetry. Association of the gestational volumes with the birth weight

OBJECTIVE

To evaluate the three dimensional ultrasound (3D) in the volume assessment of the gestational contents during the 1st trimester of pregnancy. Our aim was to correlate the embryo, gestational sac, and placenta volume with the birth weight. To monitor the increase of these volumes according to the gestational age.

METHOD

Prospective study of 199 singleton low risk pregnant women undergoing the 1st trimester ultrasound for fetal anomalies. In these women, gestational volumetry was performed and it was compared with the crown-rump length (CRL). Regression models were computed in order to analyze the dependence of birth weight with the volumes.

RESULTS

The embryo volume reveals the strongest association with the birth weight at delivery (β = 0.24), followed by the CRL (β = 0.20) and the gestational sac volume (β = 0.20). The placenta volume appears the weakest association with fetal weight at delivery (β = 0.16). All volumes increased significantly from 11(+0)-11(+6) to 13(+0)-13(+6) weeks of gestation (p < 0.001). Ten cubic millimeter increase in embryo volume corresponds to a mean birth weight increase of 75 g, while 1 mm increase in the CRL corresponds to a birth weight increase of 113 g.

CONCLUSION

Our results provide evidence that the embryo volume during the first trimester of pregnancy correlates better with birth weight than the CRL. This might assist in the identification of the high risk pregnancies caring macrosomic and low birth weight fetuses.

Association of crown-rump length at 11 to 14 weeks' gestation and risk of a large-for-gestational-age neonate

OBJECTIVE

The purpose of this study was to evaluate the association between crown-rump length (CRL) and the risk of a large-for-gestational-age (LGA) neonate.

METHODS

Data were retrospectively collected on consecutive women with a healthy singleton pregnancy followed to delivery at our center from 2003 to 2006 who underwent nuchal translucency, pregnancy-associated plasma protein-A, and free beta-human chorionic gonadotropin screening at 11 to 14 weeks' gestation. Pregnancies were dated by the last menstrual period (LMP) confirmed by CRL at 6 to 10 weeks or the known time of fertilization. The fetal CRL at 11 to 14 weeks was obtained from frozen sonographic images. The measured CRL was converted to gestational weeks using the method of Hadlock et al (Radiology 1992; 182:501-505). The expected gestational age (GA) by the LMP was subtracted from the measured GA to yield the DeltaCRL. The association between the DeltaCRL and birth weight was statistically analyzed.

RESULTS

The sample included 521 women. Fifty neonates (9.6%) were LGA (>or=90th percentile), 38 (7.3%) small for gestational age, and 433 (83.1%) appropriate for gestational age. The LGA group was characterized by significantly larger-than-expected CRL measurements (P = .033). The birth weight percentile and rate of LGA neonates were significantly higher in pregnancies in which the DeltaCRL was 1/2 week or greater (P = .007 and .033, respectively). There was a significant linear correlation between the DeltaCRL and birth weight percentile (P = .001). On multivariate logistic regression analysis, the DeltaCRL was the only significant predictor of an LGA neonate (odds ratio, 1.6; 95% confidence interval, 1.07-2.4; P = .023).

CONCLUSIONS

Pregnancies with LGA neonates are characterized by larger-than-expected CRL measurements at 11 to 14 weeks' gestation.