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R L Deter

Publications and source records attributed to R L Deter.

At least 19 recordsLinked to original sources
PubMed2006

Quantitative and morphological assessment of early gestational sacs using three-dimensional ultrasonography.

OBJECTIVE: Our main objective was to determine the value of three-dimensional ultrasonography (3DUS) and Virtual Organ Computer-aided AnaLysis (VOCAL) in the evaluation of gestational sac volume and morphology during early pregnancy. METHODS: Twenty-eight normal early pregnancies were scanned approximately every 2 weeks using transabdominal (TAS) and transvaginal (TVS) sonography. The VOCAL technique was used to create computerized surface models to classify gestational sac shapes as discoid or ellipsoid. Serial sac volume changes were analyzed using repeated measures ANOVA. Bland-Altman plots determined examiner bias and limits of agreement (LOA) for sac volume measurements. Gestational sac volumes were compared between the two-dimensional (2D) ellipsoid and VOCAL techniques. Differences between volume measurements were tested using the two-tailed paired t-test with statistical significance at the P < 0.05 level. RESULTS: Each subject was examined at a mean +/- SD menstrual age of 7.9 +/- 0.6 weeks (Scan 1), 9.9 +/- 0.6 weeks (Scan 2), and 11.9 +/- 0.6 weeks (Scan 3). Sac volumes significantly increased over time from 22 +/- 11 mL at Scan 1, to 57 +/- 21 mL at Scan 2 and 116 +/- 35 mL at Scan 3 (P < 0.001). Predominant sac shapes were classified as ellipsoid (76.2%) or discoid (23.8%). Additional descriptors included: concave (60.7%), irregular (53.6%), or smooth (7.1%), with 19% of the overall group having more than one additional shape attribute. Clinically acceptable volume measurement bias and agreement were found for the following comparisons: (1) TAS versus TVS; (2) interobserver volume measurements; and (3) intraobserver volume measurements. The VOCAL technique yielded slightly greater sac volumes (64 +/- 45.4 mL) when compared to the 2D ellipsoid model (48.6 +/- 36.8 mL) (28.9 +/- 24.3% (95% limit of agreement range, - 18.7 to 76.5%), P < 0.001). CONCLUSIONS: Reproducible sac volume measurements can be obtained using VOCAL with either TAS or TVS. Early gestational sacs variably appear as discoid or ellipsoid structures with a concave indentation from the placenta. Sac volumes can be underestimated if an ellipsoid shape is assumed. Morphological and quantitative analysis of the gestational sac may provide baseline parameters for studying patients at risk for early pregnancy failure.

Analysis of Variance↗
PubMed2004

Individualized growth assessment of fetal soft tissue using fractional thigh volume.

OBJECTIVES: The main goals of this study were to introduce fractional thigh volume (TVol) as a new soft tissue parameter for fetal growth evaluation, define its relationship to menstrual age, and develop individualized fetal growth standards based on Rossavik growth models. METHODS: A prospective, longitudinal study of 22 fetuses was conducted with conventional biometry and TVol measurements by three-dimensional ultrasonography. Infant growth outcomes were determined from modified neonatal growth assessment scores. Rossavik functions (P = c(t)k+s(t)) were used to fit complete datasets to examine relationships between TVol and model coefficients. Second-trimester models were subsequently specified from the linear slopes of growth curves before 28.0 menstrual weeks with each fetus acting as its own control. Third-trimester trajectories and birth measurements were predicted for standard growth parameters and TVol. Observed and predicted measurements were compared using percent deviations and growth potential realization index values. Four additional infants, with serial prenatal scans and postnatal evidence of intrauterine growth restriction (IUGR), were also evaluated. RESULTS: All 22 fetuses had no evidence of growth abnormalities after delivery. Accelerated soft tissue deposition occurred in the fetal thigh by 28 menstrual weeks. A mean TVol start point of 9.0 +/- 1.4 menstrual weeks was consistent with embryological studies of thigh development. Rossavik functions fitted all TVol trajectories well (mean R2 = 0.998 +/- 0.002). By fixing the coefficient k at its mean value (2.976), the fit did not change and the variabilities of coefficients c and s were reduced. The mean percent deviation between observed and predicted third-trimester TVol measurements was -0.048 +/- 7.5%. Relatively early pathological deviations were observed for TVol in all four fetuses with IUGR; in these cases the abdominal circumference was abnormal in only one fetus and thigh circumference in none. CONCLUSIONS: Individualized growth assessment can be used to accurately predict TVol during the third trimester of pregnancy and at birth. Expected growth trajectories, from second-trimester data, do not rely on population-based standards because each fetus serves as its own control. This new parameter may allow earlier detection and improved monitoring of fetal soft tissue abnormalities such as IUGR.

Female↗
PubMed2001

Perinatal morbidity and mortality rates in severe twin-twin transfusion syndrome: results of the International Amnioreduction Registry.

OBJECTIVE: Serial aggressive amnioreduction is the most widely used therapy for pregnancies that are complicated by twin-twin transfusion syndrome. Survival rates reported with this therapy are 33% to 83%, the wide range attributable to the small number of patients in these case series. Similarly, data on morbidity in survivors are imprecise. We instituted the international twin-twin transfusion syndrome registry to determine the perinatal survival and morbidity rates and the factors that influence perinatal outcome in patients with twin-twin transfusion syndrome who were treated with serial aggressive amnioreduction from 1990 to 1998. STUDY DESIGN: A total of 223 sets of twins who were diagnosed with twin-twin transfusion syndrome before 28 weeks' gestation from 20 fetal medicine referral centers were analyzed, with follow-up data until 4 weeks after birth. RESULTS: Three hundred forty-six twins (78%; 182 recipients and 164 donors) were born alive. Two hundred sixty-six twins (60%; 144 recipients and 122 donors) were alive 4 weeks after birth. Both fetuses survived to 4 weeks in 108 pregnancies (48.4%), whereas, at least 1 fetus survived in 158 pregnancies (70.8%). The interval between the last amnioreduction and delivery ranged from zero to 138 days (median, 17.5 days). In the infants who survived to 4 weeks after birth, abnormalities on neonatal cranial scan were diagnosed in 24% of recipients and in 25% of donors. Logistic regression analysis indicated that the survival rate was significantly related to gestational age at diagnosis, presence of end-diastolic blood flow in the umbilical artery velocity waveforms, presence of hydrops, mean volume of amniotic fluid removed per week, larger birth weight, and gestational age at delivery. The hemoglobin level difference at birth was the only significant parameter to predict abnormal cranial ultrasonography in newborns. CONCLUSION: These data document perinatal survival and neonatal morbidity rates in severe twin-twin transfusion syndrome that were treated by serial aggressive amnioreduction. Outcome was influenced by several perinatal risk factors, which may be used to counsel patients before and during therapy.

Amnion↗
PubMed2001

An endothelial nitric oxide synthase gene polymorphism is associated with preeclampsia.

OBJECTIVE: We sought to test the hypothesis that a polymorphism of the endothelial nitric oxide synthase gene (NOS3) is associated with preeclampsia. METHODS: We collected and performed polymerase chain reaction (PCR) on genomic DNA from pregnant patients with and without preeclampsia. Patient history and clinical course were evaluated. MAIN OUTCOME MEASURE(S): Frequency of the intron 4 polymorphism of NOS3 (designated allele A) among patients with preeclampsia compared with controls. Clinical features of patients with preeclampsia and the A allele compared with those patients with preeclampsia who did not have the A allele. RESULTS: The frequency of the A allele was 0.10 among controls versus 0.39 among patients with preeclampsia (p < 0.01). The odds ratio of developing preeclampsia when at least one A allele was present was 6.5 [95% confidence interval (CI): 2.1-19.7]. After adjusting for ethnic variation, the odds ratio increased to 7.2 (95% CI: 2.0-25.5). Among patients with preeclampsia, systolic blood pressure at the time of admission was higher for patients with at least one A allele compared with patients homozygous for the B allele (168 versus 156 mm Hg; p = 0.03), independent of gestational age (p = 0.01). CONCLUSION: These data provide evidence for an association between NOS3 and preeclampsia. In defined ethnic groups, this NOS3 may offer predictive information regarding the subsequent development of preeclampsia and its clinical course.

Adolescent↗
PubMed2001

Birth weight prediction by three-dimensional ultrasonography: fractional limb volume.

OBJECTIVE: To introduce fractional limb volume as a new ultrasonographic parameter, validate reliability of fractional limb volume measurements, develop new birth weight prediction models, and examine their practical utility for estimating fetal weight during late pregnancy. METHODS: Healthy late-third-trimester fetuses were prospectively scanned by two- and three-dimensional ultrasonography within 4 days of delivery. Volume data sets were subsequently used to extract several standard ultrasonographic measurements. Fractional limb volumes of the upper arm and thigh were based on 50% of diaphyseal bone length. Intraclass correlation was used to analyze interobserver and intraobserver reliability of fractional limb volume measurements. Several weight prediction models were developed by linear regression analysis. New prediction models were prospectively compared with the Hadlock formula in 30 healthy late-third-trimester fetuses. RESULTS: One hundred fetuses were scanned at a mean +/- SD menstrual age of 39.2 +/- 1.2 weeks. Intraclass correlation indicated a significant degree of interobserver and intraobserver reliability for fractional thigh volume. Fractional thigh volume (r = 0.86), fractional upper arm volume (r = 0.83), abdominal circumference (r = 0.83), and midthigh circumference (r = 0.82) were most highly correlated with birth weight. The best prediction model (abdominal circumference and fractional thigh volume) gave weight estimates that deviated from actual birth weight by -0.025% +/- 7.8%. For late-third-trimester fetuses, the Hadlock model yielded errors of 9.0% +/- 9.0%. Prospective testing confirmed superior performance of the new prediction model, which gave accuracy of 2.3% +/- 6.6% (Hadlock method, 8.4% +/- 8.7%). It correctly predicted 20 of 30 birth weights to within 5% of actual weight. By comparison, the Hadlock model predicted only 6 of 30 birth weights to within 5% of actual weight. CONCLUSIONS: A new birth weight prediction model, based on fractional thigh volume and abdominal circumference, is reliable during the late third trimester. It provides a means for including soft tissue evaluation for birth weight prediction. This rapid technique avoids technical limitations that currently hinder the practical implementation of three-dimensional ultrasonography for estimating birth weight.

Birth Weight↗
PubMed2000

Noninvasive diagnosis by Doppler ultrasonography of fetal anemia due to maternal red-cell alloimmunization. Collaborative Group for Doppler Assessment of the Blood Velocity in Anemic Fetuses.

BACKGROUND: Invasive techniques such as amniocentesis and cordocentesis are used for diagnosis and treatment in fetuses at risk for anemia due to maternal red-cell alloimmunization. The purpose of our study was to determine the value of noninvasive measurements of the velocity of blood flow in the fetal middle cerebral artery for the diagnosis of fetal anemia. METHODS: We measured the hemoglobin concentration in blood obtained by cordocentesis and also the peak velocity of systolic blood flow in the middle cerebral artery in 111 fetuses at risk for anemia due to maternal red-cell alloimmunization. Peak systolic velocity was measured by Doppler velocimetry. To identify the fetuses with anemia, the hemoglobin values of those at risk were compared with the values in 265 normal fetuses. RESULTS: Fetal hemoglobin concentrations increased with increasing gestational age in the 265 normal fetuses. Among the 111 fetuses at risk for anemia, 41 fetuses did not have anemia; 35 had mild anemia; 4 had moderate anemia; and 31, including 12 with hydrops, had severe anemia. The sensitivity of an increased peak velocity of systolic blood flow in the middle cerebral artery for the prediction of moderate or severe anemia was 100 percent either in the presence or in the absence of hydrops (95 percent confidence interval, 86 to 100 percent for the 23 fetuses without hydrops), with a false positive rate of 12 percent. CONCLUSIONS: In fetuses without hydrops that are at risk because of maternal red-cell alloimmunization, moderate and severe anemia can be detected noninvasively by Doppler ultrasonography on the basis of an increase in the peak velocity of systolic blood flow in the middle cerebral artery.

Blood Flow Velocity↗
PubMed1999

Individual growth patterns in the first trimester: evidence for difference in embryonic and fetal growth rates.

OBJECTIVE: To evaluate individual fetal growth during the first trimester in pregnancies resulting from spontaneous and in vitro fertilization (IVF). METHODS: The growth of 11 fetuses conceived by spontaneous fertilization (known dates of ovulation) in nine patients and 15 fetuses conceived by IVF in 12 patients were evaluated at weekly intervals from 6 weeks, menstrual age, to 14 weeks. Fetal length was determined at each examination. Measures of fetal length included the crown-rump length (CRL), maximum straight line length (MSLL) and maximum axial length (MAL). Comparisons of CRL and MSLL to MAL were carried out. The MSLL was used as the measure of length except when the MAL was available. Linear and quadratic functions were fitted to the complete data sets of individual fetuses in the two groups. Individual data sets from ten fetuses in each group were then divided into early and late growth phases, and linear functions were fitted to each data subset. Start points and pivotal points for each fetus were estimated from the coefficients of these two functions. Growth in these two groups of fetuses was compared, on the basis of slope values. RESULTS: Evaluation of length measures indicated that, before 8 weeks, only MSLL could be measured. After 8 weeks, all three measures could be obtained, with the MAL being the largest. Both the linear and quadratic models performed well with individual data sets (mean R2(+/- SD): linear 98.1 (1.0)%; quadratic 99.4 (0.4)%), with no differences found between spontaneous and IVF groups (maximum possible differences in mean slopes (95% probability): 5-8%). Similar findings were obtained for the early and late growth phase data subsets. Slope values in the early and late growth phases showed low variability (CV: early 13.5%; late 11.6%), but were significantly different (early 0.72 (+/- 0.10 SD) cm/week; late 1.21 (+/- 0.14 SD) cm/week). The mean start point was 5.9 (+/- 0.3 SD) weeks' menstrual age, while the mean pivotal point was 9.2 (+/- 0.7 SD) weeks, menstrual age. CONCLUSIONS: First-trimester growth studies in individual fetuses indicate that there is a change in length growth rate between 9 and 10 weeks, menstrual age. This is consistent with a shift in development from organogenesis to growth. These results can be used for more accurate assessment of first-trimester growth and may aid in the detection of fetal problems that manifest themselves as growth abnormalities.

Anthropometry↗
PubMed1997

Prediction of birth weight using the Rossavik growth model: a study in a Dutch population.

OBJECTIVES: To evaluate the Rossavik growth model for predicting birth weight in a Dutch population and to evaluate growth cessation near term. STUDY DESIGN: Birth weight was predicted at various ages between 38 and 42 weeks, menstrual age (MA), and at birth age in 50 normal infants using two sets of ultrasound measurements obtained before 28 weeks, MA. Predicted birth weights were compared to actual weights. The mean percentage difference was used as a measure of systematic error and the standard deviation as a measure of random error. Linear regression analysis was used to evaluate the relationship between percentage differences and birth age. To evaluate the individual growth potential, the Growth Potential Realization Index for weight (GPRIWT) was determined for each fetus. RESULTS: The predictions at 39 and 39.15 weeks, MA, were accurate without systematic error and with a random error of +/-9.3%. Prediction at 38 weeks showed a statistical underestimation (mean +/- SD = -5.8% +/- 8.8), and statistical overestimations were found for predictions after 39.15 weeks and at birth age. A relationship between percentage differences and birth age was not found for predictions between 39.15 and 40 weeks, MA. These findings indicate that growth cessation occurred at 39.15 weeks, MA. Using birth weights predicted at 39.15 weeks, MA, GPRIWT were calculated. The mean GPRIWT value was not significantly different from 100% (p > 0.05), and individual GPRIWT values ranged from 84% to 114%. CONCLUSIONS: The Rossavik growth model can be used to predict birth weight in a Dutch population. However, growth cessation near term appears to occur later than previously reported in other populations.

Birth Weight↗
PubMed1996

Prenatal prediction of neonatal growth status in twins using individualized growth assessment.

OBJECTIVE: To determine if the growth status at birth of twins can be predicted in the third trimester using the Prenatal Growth Assessment Score (PGAS). METHODS: The growth of 40 twin fetuses were studied with ultrasound from 14 weeks until delivery. Measurements of the head circumference (HC), abdominal circumference (AC), thigh circumference (ThC), femur diaphysis length (FDL), head cube (A), and abdominal cube (B) were made at 2 to 3 week intervals. Rossavik growth models for these parameters were determined from second trimester measurements. These models were used to define expected third trimester growth curves and birth characteristics. Comparisons of expected and actual third trimester measurements were used to calculate PGAS values after various time points (PGASAt) and after the last time point (PGASAT). Similar comparisons after birth were used to determine Growth Potential Realization Index (GPRI) values for HC, AC, ThC, weight (WT), and crown-heel length (CHL), with and without correction for decreased soft tissue deposition. These two sets of GPRI values were used to calculate two sets of Neonatal Growth Assessment Scores (NGASS, NGASTw). Using NGASS and NGASTw (as well as GPRI values in some cases), the twin neonates were classified as Normal (N), Decreased Soft Tissue Deposition, (DSTD), Intrauterine Growth Retardation (IUGR) and Macrosomia (M). RESULTS: At birth 22/40 (55%) were classified as N, 9/40 (22.5%) as DSTD, 6/40 (15.0%) as IUGR, and 3/40 (7.5%) as M. All -PGASAT values in the N group were greater than -0.40% with one exception (-PGASAT = -0.43%). All PGASAt values were above this same boundary except for one fetus. No differences were seen between the N and DSTD groups [mean -PGASAT (range): N, -0.12% (0% to -0.34%); DSTD, -0.10% (0% to -0.30%)]. The IUGR group had 4 fetuses with -PGASAT values between -0.65% and 2.79% and two with values of 0.0% and -0.12%. Growth retardation in the latter two was limited to a decrease in thigh soft tissue deposition. -PGASAt values in the first 4 fetuses were below -0.40% 1.6 to 9.5 weeks before delivery (mean: 6.1 weeks). Fetuses in group M had +PGASAT values of 0.0%, +1.8%, and +1.2%. PGASAt values were above +0.40% at 3.6 and 9.8 weeks before delivery in the latter two fetuses. CONCLUSIONS: These results support the concept that PGASAT and PGASAt values outside +/- 0.40% indicate either IUGR or macrosomia. Almost all fetuses with growth problems in the third trimester can be detected, on average, 6 weeks before delivery unless the growth abnormality is limited to decreased soft tissue deposition.

Anthropometry↗
PubMed1996

Flow velocity waveforms of the ductus arteriosus in appropriate and small-for-gestational-age fetuses.

OBJECTIVES: To assess ductus arteriosus velocity waveforms in the appropriate and small-for-gestational-age (SGA) fetuses. STUDY DESIGN: Ductus arteriosus flow velocity waveforms were obtained in 14 normal fetuses in a longitudinal study and in 139 normal fetuses in a cross-sectional study with pulsed and continuous Doppler ultrasonography. Ductus velocity waveforms were also determined in 25 SGA fetuses whose gestational age ranged between 20 and 34 weeks (mean +/- SD: 30 +/- 4.1 weeks). RESULTS: Mathematical modeling demonstrated that the peak systolic velocity, lowest diastolic velocity, and mean velocity of the ductus arteriosus increased with advancing gestation in both the longitudinal and cross-sectional study, but considerable individual variability was seen in the longitudinal study. The pulsatility index did not change significantly. The ductal parameters were in the normal range in all the SGA fetuses. CONCLUSIONS: The blood velocity of the ductus arteriosus increase with advancing gestation. Our results suggest that Doppler ultrasonographic study of the fetal ductus arteriosus, unlike Doppler study of the umbilical artery or middle cerebral artery, is not useful as an indicator of adverse fetal outcome.

Blood Flow Velocity↗
PubMed1995

Evaluation of twin growth status at birth using individualized growth assessment: comparison with conventional methods.

OBJECTIVE: We sought to evaluate the growth status of twins at birth using individualized growth assessment methods and to compare this assessment with that obtained with conventional methods. STUDY DESIGN: Twenty twin pregnancies were studied longitudinally with ultrasound. Measurements of the head and abdominal cubes (A,B), head circumference (HC), abdominal circumference (AC), thigh circumference (ThC), and femur diaphysis length (FDL) made in the 2nd trimester were used to specify Rossavik growth models for each parameter in each fetus. These models were used to predict weight (WT), HC, AC, ThC, and crown-head length (CHL) at birth. Actual birth measurements made within 24 hours of delivery were compared to predicted values, the latter corrected using singleton [corrects for both technical problems (TP)] or twin [corrects for both technical problems (TP) and decreased soft-tissue deposition (DSTD)] correction factors where appropriate. Two sets of growth potential realization index (GPRI) values and their corresponding neonatal growth assessment scores (NGAS) were calculated and compared to previously established normal values. Birth measurements were compared with appropriate population age-specific size curves. These data were used to characterize and classify the growth status of each twin neonate. RESULTS: Individualized growth assessment identified five primary types of growth outcomes: normal (Group I, 45%); primarily DSTD (Group II, 22.5%); IUGR (Group III, 15%); above average soft-tissue deposition (Group IV, 5%); and growth acceleration (Group V, 7.5%). Within Group I was a subgroup with evidence of DSTD (Group Ib, 33.3% of Group I). Group II could be divided into two subgroups, one with only DSTD (Group IIa, 44.4% of Group II) and one with both DSTD and other growth abnormalities (Group IIb, 55.6% of Group II). Group III had multiple growth abnormalities which were more severe than those seen in Group II. All normal neonates were AGA and had virtually all anatomic parameters within their respective normal ranges. Of the neonates with definite evidence of IUGR (Groups IIb and III), only 4 of 11 (36.4%) were SGA and only 6 of 11 (54.5%) had any of the five anatomic parameters below their respective normal ranges. Only 1 of 3 (33.3%) of neonates with growth acceleration was LGA and none (0%) of the five anatomic parameters were above their respective normal ranges. CONCLUSIONS: Individualized growth assessment methods provide a more comprehensive assessment of growth outcome in twins and detect a decrease in soft-tissue deposition not identifiable with conventional growth assessment procedures. The latter procedures are also less sensitive in the detection of both IUGR and growth acceleration.

Adolescent↗
PubMed1995

Predicting head circumference at birth: a study in a Dutch population using the Rossavik growth model.

The use of the Rossavik growth model for predicting neonatal head circumference from data obtained from two ultrasound scans before 28 weeks' menstrual age was investigated in 50 pregnant women with singleton pregnancy in a Dutch population. The head circumference predicted at 38, 39, 39.5 and 40 weeks' gestation and at birth was compared to the head circumference observed at birth. The accuracy was expressed in percentage difference and the growth potential realization index (GPRIHC) was used as an indicator of growth outcome. The predictions at 39.5 weeks and 40 weeks were accurate without systematic error. Prediction at 38 weeks showed a statistical underprediction (mean +/- SD = -2.3 +/- 2.0%, p < 0.05) and at birth a systematic overprediction (mean +/- SD = +1.4 +/- 2.1%, p < 0.05). Based on the regression analyses of percentage differences against birth ages, the growth of the head circumference appeared to stop at about 39.5 weeks. The results of the present study were compared to studies of populations in the United States. The growth of the head circumference before 28 weeks was similar in all samples studied, but growth cessation was at 38 weeks in the fetuses in the USA and at 39.5 weeks in these Dutch fetuses. The mean values of GPRIHC were not different from 100% in all samples studied and the ranges were similar (mean, 100.3%; range, 97-103% in the present study).

Algorithms↗
PubMed1995

Modified neonatal growth assessment score: a multivariate approach to the detection of intrauterine growth retardation in the neonate.

The objective of this investigation was the development of a modified Neonatal Growth Assessment Score (mNGAS) for use in the evaluation of neonatal growth status. The growth of 74 fetuses at risk for intrauterine growth retardation (IUGR) was followed longitudinally, beginning in the first or early second trimester. Rossavik growth models derived from data obtained in the second trimester were used to predict the weight (WT), crown-heel length (CHL) and head (HC), abdominal (AC) and thigh circumferences (ThC) at birth, which were then actually measured within 24 h after delivery. These measurements were compared to age-specific size curves and used to calculate sets of five growth potential index (GPRIi) values, which in turn were used to calculate five-variable Neonatal Growth Assessment Scores (NGAS5). Neonates were initially classified as normal or IUGR on the basis of NGAS5, GPRIi, and anatomic measurements. A final classification based on principal component analysis and linear discriminant analysis was carried out. The score obtained using the first principal component function was defined to be mNGAS51. The effectiveness of mNGASij values, determined from 1-4 GPRIi values, in separating normal and IUGR neonates was also evaluated. Neonates initially considered to be normal had very few abnormal GPRI values or anatomic measurements, whereas the frequency of these abnormalities in IUGR neonates was significantly increased. However, no single anatomic variable was 100% normal in the normal neonates and 100% abnormal in IUGR neonates. Only 40% of IUGR neonates were small for gestational age. Classification of these neonates using principal component analysis and linear discriminant analysis was essentially the same (98.6%) as that made initially after reclassification of two IUGR neonates as normal. The characteristics of the initial and final normal and IUGR groups were very similar and the mNGAS51 was strongly correlated with the NGAS5 in the IUGR group. The effectiveness of mNGASij in separating normal and IUGR neonates increased with the number of GPRIi values included and the types used. GPRIThC and GPRIWT were the most important, followed by GPRIAC. GPRICHL and GPRIHC were much less important and in some cases detrimental. These findings support the concepts of a decrease in soft tissue mass as the initial step in the development of IUGR and the protection of head growth (brain-sparing). The characteristics of mNGAS51, particularly its comprehensiveness, its independence of differences in growth potential, its weighting of GPRIi values according to their importance in the detection of IUGR and its ability to detect different manifestations of IUGR in different individuals, indicate that this should be a most effective parameter for separating normal and IUGR neonates.

Embryonic and Fetal Development↗
PubMed1994

Small-for-menstrual-age infants: different subgroups detected using individualized fetal growth assessment.

Our purpose was to study the individual fetal growth patterns of infants who were born small-for-menstrual-age. Growth in the second and third trimester was assessed in 98 small-for-menstrual-age infants, using individual fetal growth curves generated by the growth model: P = c(t)k+s(t). Growth indices were compared with those previously reported for that method in infants with normal growth. The small-for-menstrual-age infants were distributed into four growth patterns, ie, infants with either normal or decreased second-trimester growth indices, who, by the time of birth, succeed or fail in fulfilling their individual growth potential. These four growth patterns appear to be associated with different pathophysiological mechanisms and incidences of perinatal complications. Individual fetal growth assessment identifies differences in genetically determined growth and differentiates between fetuses who achieve their growth potential and those with growth failure who are at greater risk for fetal compromise.

Adult↗
PubMed1994

Prediction of the neonatal crown-heel length from femur diaphysis length measurements.

The usefulness of the Rossavik growth model in predicting crown-heel length (CHL) was evaluated in 50 women with normal singleton pregnancies in a Dutch population. The femur diaphysis lengths (FDL) were predicted assuming growth cessation at 38, 39, 39.5, and 40 weeks, menstrual age (MA), and at birth using Rossavik growth models determined from two second-trimester FDL measurements. Predicted CHLs were then calculated from predicted FDLs using six different equations. Predicted CHLs were compared with the actual neonatal CHLs and the percent differences calculated. The growth potential realization index (GPRI) values were also determined. With all six equations, regression analysis revealed a significant relationship between the percent differences and birth ages for those infants delivering after 38 and 39 weeks, MA, respectively. The signs of the slopes of the regression lines were negative, indicating continued growth of these fetuses. With the Vintzileos equation, no evidence of continued growth was obtained after 39.5 weeks, MA. The systematic prediction error at this time point was 0.9%, whereas the random error was 3.3%. The mean GPRICHL was 99%, with a 95% range of 93% to 104%. These findings indicate that the CHL can be predicted with a high degree of accuracy in this Dutch population if the appropriate growth cessation age and FDL-CHL function are used.

Adolescent↗