160 Abnormal Amniotic Fluid Volume and Fetal Structural Defects
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157 158 Volume 166 Number 1, Part 2 BIOMETRY OF THE FETAL MANDIBLE. l::......Q.uQ. L.D. Platt, Dept. Ob/Gyn. Cedars-Sinai Med. Cntr./UCLA. Los Angeles, CA The fetal mandible has not previously been studied in an objective fashion. A plane was established that measures one ramus of the jaw. The prox.imal landmark, the temporomandibular joint, is visualized below the level of the orbits in an axial section and the anechoic cartilaginous area between the mandibular rami. the symphysis mentis, is the distal landmark. One hundred and thirty two subjects were identified and studied in a cross sectional manner. All measurements were made by one author (e.O.) with commonly available ultrasound equipment. Patients studied were without known medical or obstetric complications and had a known last menstrual period(LMP) and either a positive pregnancy test within 6 weeks of the LMP or an ultrasound at less than 20 weeks of gestation that confirmed the LMP. No fetus 4 studied had an abnormai 35 karyotype or structural mal- formation identified at birth. '3 Measurement of three separate images of mandible length were 25 ohtained and averaged. Stat- 2 istical analysis was performed on a Macintosh II using Stat View II 15 statistical software package. With the mandible length as I 1.5 2. 2'ManalbleGgth4 4.5 5 5.5 independent variable, an equation for predIcting gestatIOnal age was derived by polynomial least squares regression. There was a high degree of correlation with an adjusted R2 of 0.963. The accompanying figure is a scatterplot of the data and the regression formula. An additional 31 fetuses were measured by the authors to evaluate interobserver variation. There was no significant difference in the measurements of the two observers. Conclusion: The size of the fetal mandible correlates well with and may be used 10 predict gestational age. The landmarks of the measurement are reproducible and interobserver variation is acceptable. Further studies may allow delineation of growth of the fetal jaw in pathologic conditions and precise, objective determination of micrognathia. BIPARIETAL DIAMETER PREDICTS NEONATAL SURVIVAL AS WELL AS ACTUAL BIRTH WEIGHT IN THE 500-1,000 GRAM INFANT. RS SmithX, and SF Bottoms. Wayne State Univ., Hutzel Hospital, Detroit, MI. Determining neonatal prognosis for the severely premature fetus is difficult but important in counseling and guiding obstetrical management. The obstetrician must rely on survival rates based on birth weight; error in estimated fetal weight limits the confidence regarding prognosis before delivery. In an attempt to improve the accuracy of prenatal predictions of survival we studied 130 singleton liveborn infants having birth weights of 500-1,000 grams and complete ultrasound examinations within 3 days of delivery_ Birth weights wcre uniformly distributed. 80 infants survived; 50 died. For purposes of comparison, estimated fetal weight, biparietal diameter (BPD), femur, birth weight, and pediatric estimate of gestational age were evaluated as screening tests for neonatal survival using receiver-operator characteristic (ROC) curves. In this model, sensitivity and false positive rate were calculated using each value of every parameter as a cut point to predict survival. Visual inspection of the ROC curves indicated that BPD was the best single predictor. Prognostic tables based directly on obstetrical parameters were generated. Among infants < 800 grams, discriminant function analysis revealed that cesarean birth was associated with a higher survival rate, and that underestimation of fetal weight was linked with a lower cesarean rate and a worse prognosis. Irrespective of controlling for route of delivery, BPD did as well as actual birth weight and all other parameters in predicting survival. We speculate this is due to BPD being less subject to variation in growth; it may provide the most accurate estimate of gestational age in this weight range. 159 160 spa Abstracts 323 ASSESSMENT OF EARLY FETAL GROWTH IN DIABETIC PREGNANCIES BY VAGINAL SONOGRAPHY.Laxmi Baxi,Tcssic Tharakan x ,Ana MonteagudaX ,IIan Timor. Dcpt.of<?b/Gyn, College of P & S, Columbia Univ.& Columbia Presbyterian Medical Center, New York, Inadequate glycemic control early in diabetic pregnancies is associated with an increased incidence of congenital malformations. Pedersen has reported early growth delay in these patients. We prospectively studied early fetal growth in 37 diabetic and 30 control pregnancies, all of whom had at least two vaginal sonograms hetwccn 40 and 112 days of gestation. Glycosylated hemoglobin (HbA 1) mCliSurcmcnts reflected glycemic control in early pregnancy. A discrepancy of >0.5 wks. was labeled as carly growth delay. Control of Early growth delay No growth delay Tot Diabetes No walfOrD) "No 'malronu walrorm walronn Poor 9 2 14 2 27 IIbAl>8.5 Good I 0 9 0 10 IIbAl<8.5 Total 10 2 23 2 37 cauda regression syndrome. -bilateral ydrolhorax, telralogy 0 Fal101, 'megaloureter, ·4 spontaneous abortions, X 2 -3.147, P-ns. Of 37 diabetic patients, 27 had elevated HhAI (>8.5%), indicating poor control, in the first trimester. Eleven of these had growth delay (40.7%). Delayed grm'lth was seen in 1/10 in patients with well controlled diahetes (P-ns). In conclusion, using vaginal ultrasound, we did not detcct increased incidence of early growth delay in all diabetic pregnancies. However. the delay was Significant in patients with suboptimal glycemic control as compared to non-diahctic patients (X2-4.079, P< .05). (Supporled by a granr from the Diabetic Foundation) ABNORMAL AMNIOTIC FLUID VOLUME AND FETAL STRUCTURAL DEFECTS. H.M. Wolfe, M.P. Dombrowski, S.F. Bottoms, I.E. Zador', R.J. Sokol, Dept. of Ob/Gyn, Hutzel Hosp.!Wayne State Univ., Detroit, MI To date, studies of amniotic fluid volume (AFV) have focused primarily on extremes of AFV (oligohydramnios (oligo) and polyhydramnios (poly)) and their association with specific anomalies. We studied 3456 patients at greater than 15 weeks gestation. Abnormal (abn) AFV, by subjective and objective criteria, was grouped as oligo, decreased (decr), increased liner) and poly. Each was compared to normal AFV for sonographically detected abnormalities of major organ systems. Odds ratios and 95% confidence limits (CL) were calculated. As expected, oligo was associated with an increased frequency of GU anomalies (39.2x) and poly with GI (21.0x) anomalies. Interestingly deer AFV was associated with an increase in heart (40x) and GI anomalies (12.9x). Heart (19.4xl. umbilical cord (3.8x) and GI (27.8x) anomalies were also more common with incr AFV as indicated below (.p < .05). Stomach Bladder Kidney Umbilical Cord Heart Intestines Ventricles Total Odds Ratio: 95% CL Oligo Decr NI Incr 0/49 0/236 1/3006 1 I 111 " 2/51" 0/234 0/2994 0/110 2/49" 1/219 4/2848 1/111 0/13 0/155 5/2396 1/107 1/20" 6/125" 2/1589 2/84" 0/40 3/209< 2/2944 2/109< 1/61" 0/215 3/2288 0/107 Poly 0/19 0/19 0/18 1/18< 0/16 1/17" 1/17" 18.9 6.3 1.0 11.0 26.6 7.3-49.2 2.9-13.6 4.8-25.5 7.2-98.3 Overall, the risk of anomalies is 6-26x greater with any departure from sonographically normal AFV. In fact, the incidence among cases of oligo and poly is not significantly increased when compared to incr and deer AFV. AFV reflects a continuum of risk. Patients with abn AFV, even those not meeting formal criteria for poly or oligo, should be considered at substantially increased risk for anomalies and carefully evaluated prenatally for their presence.
Transcript of 160 Abnormal Amniotic Fluid Volume and Fetal Structural Defects
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158
Volume 166 Number 1, Part 2
BIOMETRY OF THE FETAL MANDIBLE. l::......Q.uQ. L.D. Platt, Dept. Ob/Gyn. Cedars-Sinai Med. Cntr./UCLA. Los Angeles, CA
The fetal mandible has not previously been studied in an objective fashion. A plane was established that measures one ramus of the jaw. The prox.imal landmark, the temporomandibular joint, is visualized below the level of the orbits in an axial section and the anechoic cartilaginous area between the mandibular rami. the symphysis mentis, is the distal landmark. One hundred and thirty two subjects were identified and studied in a cross sectional manner. All measurements were made by one author (e.O.) with commonly available ultrasound equipment. Patients studied were without known medical or obstetric complications and had a known last menstrual period(LMP) and either a positive pregnancy test within 6 weeks of the LMP or an ultrasound at less than 20 weeks of gestation that confirmed the LMP. No fetus 4
studied had an abnormai 35 karyotype or structural malformation identified at birth. '3
Measurement of three separate images of mandible length were 25
ohtained and averaged. Stat- 2
istical analysis was performed on a Macintosh II using Stat View II 15
statistical software package. I",",-:--c-',,":",;---::-"":-::-'""":",,:~-:--';'; With the mandible length as I 1.5 2. 2'ManalbleGgth4 4.5 5 5.5
independent variable, an equation for predIcting gestatIOnal age was derived by polynomial least squares regression. There was a high degree
of correlation with an adjusted R2 of 0.963. The accompanying figure is a scatterplot of the data and the regression formula. An additional 31 fetuses were measured by the authors to evaluate interobserver variation. There was no significant difference in the measurements of the two observers. Conclusion: The size of the fetal mandible correlates well with and may be used 10 predict gestational age. The landmarks of the measurement are reproducible and interobserver variation is acceptable. Further studies may allow delineation of growth of the fetal jaw in pathologic conditions and precise, objective determination of micrognathia.
BIPARIETAL DIAMETER PREDICTS NEONATAL SURVIVAL AS WELL AS ACTUAL BIRTH WEIGHT IN THE 500-1,000 GRAM INFANT. RS SmithX, and SF Bottoms. Wayne State Univ., Hutzel Hospital, Detroit, MI.
Determining neonatal prognosis for the severely premature fetus is difficult but important in counseling and guiding obstetrical management. The obstetrician must rely on survival rates based on birth weight; error in estimated fetal weight limits the confidence regarding prognosis before delivery. In an attempt to improve the accuracy of prenatal predictions of survival we studied 130 singleton liveborn infants having birth weights of 500-1,000 grams and complete ultrasound examinations within 3 days of delivery_ Birth weights wcre uniformly distributed. 80 infants survived; 50 died. For purposes of comparison, estimated fetal weight, biparietal diameter (BPD), femur, birth weight, and pediatric estimate of gestational age were evaluated as screening tests for neonatal survival using receiver-operator characteristic (ROC) curves. In this model, sensitivity and false positive rate were calculated using each value of every parameter as a cut point to predict survival. Visual inspection of the ROC curves indicated that BPD was the best single predictor. Prognostic tables based directly on obstetrical parameters were generated. Among infants < 800 grams, discriminant function analysis revealed that cesarean birth was associated with a higher survival rate, and that underestimation of fetal weight was linked with a lower cesarean rate and a worse prognosis. Irrespective of controlling for route of delivery, BPD did as well as actual birth weight and all other parameters in predicting survival. We speculate this is due to BPD being less subject to variation in growth; it may provide the most accurate estimate of gestational age in this weight range.
159
160
spa Abstracts 323
ASSESSMENT OF EARLY FETAL GROWTH IN DIABETIC PREGNANCIES BY VAGINAL SONOGRAPHY.Laxmi Baxi,Tcssic Tharakanx ,Ana MonteagudaX ,IIan Timor. Dcpt.of<?b/Gyn, College of P & S, Columbia Univ.& Columbia Presbyterian Medical Center, New York,
Inadequate glycemic control early in diabetic pregnancies is associated with an increased incidence of congenital malformations. Pedersen has reported early growth delay in these patients. We prospectively studied early fetal growth in 37 diabetic and 30 control pregnancies, all of whom had at least two vaginal sonograms hetwccn 40 and 112 days of gestation. Glycosylated hemoglobin (HbA 1) mCliSurcmcnts reflected glycemic control in early pregnancy. A discrepancy of >0.5 wks. was labeled as carly growth delay.
Control of Early growth delay No growth delay Tot
Diabetes No walfOrD) "No 'malronu walrorm walronn
Poor 9 2 14 2 27 IIbAl>8.5
Good I 0 9 0 10 IIbAl<8.5
Total 10 2 23 2 37 cauda regression syndrome. -bilateral ydrolhorax, telralogy 0 Fal101,
'megaloureter, ·4 spontaneous abortions, X2-3.147, P-ns. Of 37 diabetic patients, 27 had elevated HhAI (>8.5%), indicating poor control, in the first trimester. Eleven of these had growth delay (40.7%). Delayed grm'lth was seen in 1/10 in patients with well controlled diahetes (P-ns). In conclusion, using vaginal ultrasound, we did not detcct increased incidence of early growth delay in all diabetic pregnancies. However. the delay was Significant in patients with suboptimal glycemic control as compared to non-diahctic patients (X2-4.079, P< .05). (Supporled by a granr from the Diabetic Foundation)
ABNORMAL AMNIOTIC FLUID VOLUME AND FETAL STRUCTURAL DEFECTS. H.M. Wolfe, M.P. Dombrowski, S.F. Bottoms, I.E. Zador', R.J. Sokol, Dept. of Ob/Gyn, Hutzel Hosp.!Wayne State Univ., Detroit, MI
To date, studies of amniotic fluid volume (AFV) have focused primarily on extremes of AFV (oligohydramnios (oligo) and polyhydramnios (poly)) and their association with specific anomalies. We studied 3456 patients at greater than 15 weeks gestation. Abnormal (abn) AFV, by subjective and objective criteria, was grouped as oligo, decreased (decr), increased liner) and poly. Each was compared to normal AFV for sonographically detected abnormalities of major organ systems. Odds ratios and 95% confidence limits (CL) were calculated. As expected, oligo was associated with an increased frequency of GU anomalies (39.2x) and poly with GI (21.0x) anomalies. Interestingly deer AFV was associated with an increase in heart (40x) and GI anomalies (12.9x). Heart (19.4xl. umbilical cord (3.8x) and GI (27.8x) anomalies were also more common with incr AFV as indicated below (.p < .05).
Stomach Bladder Kidney Umbilical Cord Heart Intestines Ventricles
Total Odds Ratio: 95% CL
Oligo Decr NI Incr 0/49 0/236 1/3006 1 I 111 " 2/51" 0/234 0/2994 0/110 2/49" 1/219 4/2848 1/111 0/13 0/155 5/2396 1/107 1/20" 6/125" 2/1589 2/84" 0/40 3/209< 2/2944 2/109< 1/61" 0/215 3/2288 0/107
Poly 0/19 0/19 0/18 1/18< 0/16 1/17" 1/17"
18.9 6.3 1.0 11.0 26.6 7.3-49.2 2.9-13.6 4.8-25.5 7.2-98.3
Overall, the risk of anomalies is 6-26x greater with any departure from sonographically normal AFV. In fact, the incidence among cases of oligo and poly is not significantly increased when compared to incr and deer AFV. AFV reflects a continuum of risk. Patients with abn AFV, even those not meeting formal criteria for poly or oligo, should be considered at substantially increased risk for anomalies and carefully evaluated prenatally for their presence.
