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Objective To describe the process of training for measuring nuchal translucency at five clinical centers in North America and to evaluate methods of quality assurance and feedback. Design Throughout a period of 18 months, the performance of sonographers in measuring fetal nuchal translucency was monitored using qualitative and quantitative methods of review. After 12 months, different approaches (written and personal feedback) were used to inform sonographers of technical aspects that needed to or could be improved. Results On initial qualitative review, discrepancies in judgment from different reviewers coincided with suboptimal magnification, failure to visualize the amniotic membrane and/or use of cross-shaped calipers. At subsequent global review, 13 (29%) images of nuchal translucency measurements were considered unacceptable. Quantitative assessment revealed that, during the first part of the study, the means from four sonographers were significantly smaller and the mean from the fifth sonographer was significantly larger than expected on the basis of findings from The Fetal Medicine Foundation (P < 0.0001). Following feedback, sonographers who underestimated nuchal translucency and who received a written report only did not change measurements overall ( P = 0.9759). In contrast, those who received additional intervention showed a marked difference ( P < 0.0001). Conclusions Global qualitative review of images from one sonographer may be preferable to assessment of individual aspects of images. Results from global qualitative review correspond well with findings from quantitative analysis, indicating that the latter can be applied for ongoing audit. Observation of divergent results should prompt extensive personal feedback, rather than a written report, to prevent sonographers from settling in their own, inappropriate technique.

Eighty-two consecutive fetuses with ultrasound evidence of isolated pyelectasis (defined as dilatation in the anteroposterior renal pelvic dimension of ≥ 4 mm) were prospectively followed to determine the risk for postnatal uropathy and Down syndrome. In 98 (60%) kidneys, isolated pyelectasis was shown to be the first manifestation of a pathophysiological process that evolved into a gamut of postnatal uropathies (defined as urological conditions requiring remedial surgery or extended medical surveillance). Data quantifying the risk for postnatal uropathy in fetuses with varying degrees of isolated pyelectasis, at different gestational ages, are presented in figure format to facilitate prenatal counselling. Bivariate analysis showed that the evolution of isolated pyelectasis to uropathy was statistically significant when in utero progression was noted or in conjunction with other findings including contralateral pyelectasis (p < 0.01), male gender (p < 0.01) and increased kidney length (p < 0.001). Importantly, 55% of the infants requiring corrective surgery demonstrated in utero progression of pyelectasis (p < 0.002). Serial ultrasound examinations were necessary to evaluate progression or regression in the extent of pyelectasis. Finally, isolated pyelectasis was associated with an increased risk for Down syndrome, beginning at maternal age of 31 years, in the interval of 16–20 weeks' gestation. Copyright © 1996 International Society of Ultrasound in Obstetrics and Gynecology

Objective : To determine the incidence of chromosomal abnormalities among fetuses with isolated pyelectasis. Methods : Between March 1991 and March 1994, 121 cases of isolated fetal pyelectasis were identified at our institution. Pyelectasis was defined as a renal pelvis anteroposterior diameter of at least 4 mm before 33 weeks' gestation, and at least 7 mm at 33 weeks or thereafter. Once identified, women were offered antenatal genetic testing; if they declined, consent was sought for umbilical cord blood studies at delivery. Results : Chromosomal evaluation was available in 99 women. Two chromosomal abnormalities were identified: one trisomy 21 and one mosaic 46,XY/47,XYY. The ages of the women were 32 and 28 years, respectively. Calculation of adjusted risks for Down syndrome and all chromosomal abnormalities indicated a 3.9-fold increase in Down syndrome risk and a 3.3-fold increase in risk for all chromosomal abnormalities in the presence of isolated fetal pyelectasis. Conclusion : Isolated fetal pyelectasis is associated with increased risk, over that related to age, for both Down syndrome and all chromosomal abnormalities. These factors may be valuable in counseling individual patients regarding the appropriateness of amniocentesis.

The echo patterns of endometriomas have been described by both transabdominal and transvaginal scanning. This retrospective study was undertaken to evaluate the degree of internal echogenicity in endometriomas preoperatively scanned by both techniques. Transvaginal ultrasound scanning should be added to the diagnostic armamentarium. (J Gynecol Surg 11:27, 1995)

Objective: Our purpose was to prospectively evaluate the risk of chromosomal abnormalities associated with isolated choroid plexus cyst(s) in gravid women undergoing second-trimester ultrasonographic examination. Study Design: During a 24-month period 9100 pregnant women underwent midtrimester ultrasonographic evaluation. Women with a fetal diagnosis of choroid plexus cyst(s) were offered amniocentesis and a repeat examination in 4 to 6 weeks. Results: A diagnosis of choroid plexus cyst(s) was made in 102 fetuses (1.1 %). In four of these fetuses multiple congenital anomalies were noted. Three of the four fetuses had a chromosomal abnormality, two trisomy 18 and one unbalanced translocation, t(3;13). In the remaining 98 fetuses the choroid plexus cysts were isolated findings, that is, there were no other ultrasonographically detected anomalies. Seventy-five of these 98 fetuses underwent amniocentesis. An abnormal karyotype was identified in four fetuses: three had Down syndrome (two trisomy 21 and one unbalanced translocation, t[14;211), and one trisomy 18. The offspring of,the 23 patients in which amniocentesis was declined were phenotypically normal. Conclusions: In our prospective study the risk of chromosomal abnormality with isolated choroid plexus cyst(s) was 1:25, a risk that exceeds the 1:200 risk of pregnancy loss after amniocentesis and the 1:126 and 1:260 risk for aneuploidy and Down syndrome, respectively, in a 35-year-old pregnant women during the midtrimester. These findings indicate that amniocentesis should be offered to pregnant women in the presence of isolated fetal choroid plexus cyst(s).

The transvaginal ultrasound echo patterns of 39 surgically proven cystic teratomas were retrospectively reviewed. Six different ultrasound echo patterns could be differentiated, ranging from purely cystic to densely echogenic. Importantly, in 82% of the tumors, areas of dense echogenicity were noted. Although the transvaginal appearance of cystic teratomas may allow correct preoperative prediction, the variable nature of the echo patterns makes dtfferentiation from malignant tumors difficult. Copyright © 1993 International Society of Ultrasound in Obstetrics and Gynecology

We studied longitudinal ultrasonographic growth patterns (abdominal circumference, biparietal diameter) initiated early in gestation in 52 pregnancies complicated by pregestational diabetes mellitus and 19 controls. Three predominant patterns of growth were ascertained including a heretofore unrecognized pattern characterized by accelerated abdominal circumference growth (greater than 90th percentile) before 24 weeks' gestational age. Maternal and neonatal anthropometric and metabolic parameters were contrasted for the three patterns. The findings suggest that in some cases of diabetic macrosomia that can be recognized before 24 weeks' gestation, augmented growth may be influenced by factors other than fetal hyperinsulinism.

Counseling for pyelectasis in the late 2nd trimester is usually based only upon assessing the antero-posterior (AP) width of the renal pelvis. We hypothesized that checking additional features would better predict postnatal outcome.Ultrasound (24 weeks gestational age (GA)) and newborn outcome data collected prospectively since 1986 were analyzed retrospectively. We determined if outcome predictions in kidneys with a sonographically evident renal pelvis (SERP), which had evaluation of additional features (e.g., renal and bladder lengths, presence of a dilated ureter or dilated calyces) are more accurate than those that did not have these features.There were 286 fetuses studied with pediatric follow-up of an average of 6.5 years. There were 338 exams providing 459 ultrasound images with SERP. Additional features were not assessed in 183 fetuses; however 103 fetuses did have evaluation of additional features. These features were categorized as abnormal (92) or as normal (11). Fetuses with SERP and abnormal additional features required extensive urological care or died 6.1 times more often than fetuses in which additional features were not examined (p0.001) and 12.9 times more often when additional features were normal (p0.001).Fetal kidneys with SERP (24 weeks GA) and an abnormal additional ultrasound feature had extensive pediatric care significantly more often than when such features were not evaluated or were normal.

Screening for aneuploid pregnancies is routinely performed after 15 weeks of gestation and has a sensitivity of approximately 65 percent, with a false positive rate of 5 percent. First-trimester markers of aneuploidy have been developed, but their use in combination has not been adequately evaluated in clinical practice.We conducted a multicenter study of screening for trisomies 21 and 18 among patients with pregnancies between 74 and 97 days of gestation, based on maternal age, maternal levels of free beta human chorionic gonadotropin and pregnancy-associated plasma protein A, and ultrasonographic measurement of fetal nuchal translucency. A screening result was considered to be positive for trisomy 21 if the calculated risk was at least 1 in 270 pregnancies and positive for trisomy 18 if the risk was at least 1 in 150.Screening was completed in 8514 patients with singleton pregnancies. This approach to screening identified 85.2 percent of the 61 cases of Down's syndrome (95 percent confidence interval, 73.8 to 93.0), with a false positive rate of 9.4 percent (95 percent confidence interval, 8.8 to 10.1). At a false positive rate of 5 percent, the detection rate was 78.7 percent (95 percent confidence interval, 66.3 to 88.1). Screening identified 90.9 percent of the 11 cases of trisomy 18 (95 percent confidence interval, 58.7 to 99.8), with a 2 percent false positive rate. Among women 35 years of age or older, screening identified 89.8 percent of fetuses with trisomy 21, with a false positive rate of 15.2 percent, and 100 percent of fetuses with trisomy 18.First-trimester screening for trisomies 21 and 18 on the basis of maternal age, maternal levels of free beta human chorionic gonadotropin and pregnancy-associated plasma protein A, and measurement of fetal nuchal translucency has good sensitivity at an acceptable false positive rate.

Arteriovenous malformation of the uterus is a rare uterine abnormality. This entity is generally associated with the presence of molar disease, choriocarcinoma and uterine surgery, but may be congenitally acquired. The presence of an arteriovenous malformation generally leads to unexplained profuse uterine bleeding. The diagnosis of this entity has traditionally been made by arteriography, and the treatment is usually hysterectomy. We present a patient with an arteriovenous malformation of the uterus whose prior delivery was by Cesarean section. The patient experienced episodes of heavy vaginal bleeding in the first month following the procedure of suction curettage for a first-trimester pregnancy loss. Chorionic villus sampling performed prior to the procedure showed a chromosomally normal fetus. The diagnosis of an arteriovenous malformation was made by color Doppler velocimetry and confirmed with arteriography. The patient desired to maintain her fertility. Interventional radiological techniques were successfully utilized to obliterate the arteriovenous malformation with the use of polyvinyl alcohol particles (250 micro m) and gelfoam. Discussion includes the presenting signs and symptoms along with the method of both diagnosis and conservative management.

Objective: To assess the risk of trisomy 18 and trisomy 21 associated with isolated choroid plexus cysts diagnosed by ultrasound in the second trimester. Methods of Study Selection: We reviewed the unabridged PREMEDLINE and MEDLINE databases for articles written in the English language regarding second-trimester fetal isolated choroid plexus cysts and trisomies 18 and 21, published in the period 1987–1997. Selection criteria included only second-trimester, prospective studies in which the rate of fetal isolated choroid plexus cysts could be calculated, the number of fetuses with trisomy 18 and 21 was reported clearly, and pregnant women of all ages were included, rather than only those at high risk for aneuploidy due to advanced maternal age. Tabulation and Results: Thirteen prospective studies, comprising 246,545 second-trimester scans, were selected. Among 1346 fetuses with isolated choroid plexus cysts, seven had trisomy 18, and five had trisomy 21. For each study, a 2 × 2 table was constructed and the likelihood ratio of a positive test was computed. The likelihood ratios for trisomies 18 and 21 were found to be homogeneous (P = .08 for trisomy 18, and P = .16 for trisomy 21). The summary likelihood ratio and 95% confidence interval (CI) for each chromosomal abnormality were calculated using the Mantel-Haenszel fixed effects model of meta-analysis. The summary likelihood ratio for trisomy 18 was 13.8 (CI 7.72, 25.14, P < .001) and for trisomy 21 was 1.87 (CI 0.78, 4.46, P = .16). Conclusion: The likelihood of trisomy 18 was 13.8 times greater than the a priori risk in fetuses with isolated choroid plexus cysts diagnosed in the second trimester. However, the likelihood of trisomy 21 was not significantly greater than the a priori risk with isolated choroid plexus cysts. The data supported offering pregnant women karyotyping to rule out trisomy 18 when maternal age at delivery is 36 years or older, or when the risk for trisomy 18 detected by serum multiple-marker screen is more than one in 3000.

OBJECTIVE: The objective of this study was to determine the significance of isolated hyperechoic fetal bowel STUDY DESIGN: Forty-five cases with prospective, ultrasonographic diagnosis of isolated hyperechoic fetal bowel were reviewed. Fetal variables, including aneuploidy, deoxyribonucleic acid studies for cystic fibrosis, congenital infection, growth retardation, and intrauterine death were reported. RESULTS: Thirty-four of the 45 cases (76%) resulted in live-born infants without detected abnormalities. However, hyperechoic bowel was associated with cystic fibrosis in two cses (4%), congenital infection in two cases (4%), and fetal alcohol syndrome in one case. Termination of pregnancy was elected in three casees and intrauterine fetal death occurred in three cases (7%). Growth retardation was observed in five of 39 (13%) live-born infants. CONCLUSION: Isolated hyperechoic fetal bowel is associated with significant pathologic disorders. Women whose fetuses are diagnosed as having isolated hyperechoic bowel should be offered additional prenatal diagnostic options, including maternal serologic studies for congenital infection, fetal karyotype, and deoxyribonucleic acid testing for cystic fibrosis. In addition, continuing ultrasonographic evaluation to fetal growth and antenatal biophysical assessment should be considered.

Objective To evaluate the perinatal outcome in fetuses with single umbilical artery detected on targeted prenatal ultrasound without other anomalies. Methods During a 3.5-year period, an isolated single umbilical artery was suspected on prenatal ultrasound examination in 57 fetuses evaluated at two referral centers. Targeted imaging to rule out concurrent fetal anomalies was normal in all cases. Pregnancy and perinatal outcome data were retrieved by review of the medical records or from conversations with referring physicians. Complete follow-up was available in 50 cases. Results A two-vessel umbilical cord was confirmed at birth in 50 neonates. The mean gestational age at delivery was 38.6 ± 2.8 weeks; the mean birth weight was 3202.8 ± 835.8 g. Seventeen patients (34%) underwent genetic amnio-centesis, and all fetuses had a normal karyotype. The only neonate ascertained to have a congenital anomaly after birth was diagnosed with total anomalous pulmonary venous return. This neonate underwent a corrective surgical procedure and is thriving with no apparent problems at 3.5 years of age. There were no perinatal deaths. Conclusion In the absence of additional sonographically detectable anomalies, an isolated single umbilical artery does not seem to affect clinical outcome and therefore should not alter routine obstetric management.

Doppler umbilical artery velocimetry was performed in 40 chemically dependent women. The mean S/D ratio was 2.7 with 15/66 values greater than or equal to 3.0. No cases of absent or reverse end-diastolic flow were noted. The mean S/D ratio in women with positive toxicologies for cocaine use was not statistically elevated compared to women with negative screens (2.8 versus 2.7, P = 0.51). In this study an S/D ratio greater than or equal to 3.0 had a sensitivity of 40% for identifying intrauterine growth retardation with a positive predictive value of 20%.

Ultrasound is assuming an essential role in the detection of fetal cranial and spinal anomalies. Illustrated in this article is the sonographic appearance of cranial abnormalities wherein the diagnosis of encephalocele is clear cut because the anatomic defect of the neural tube is visualized. Additionally presented is a variety of cranial and craniocervical cystic masses, including meningocele, wherein the anatomic defect of the neural tube is not apparent and the diagnosis is reached by careful attention to the specific ultrasonic characteristics of each mass.

Sixty-seven women with primary addiction to cocaine were evaluated during their pregnancies by multiple ultrasound studies. Ultrasonic parameters included biparietal diameter, femur length, abdominal circumference, and head circumference. These values were compared with ultrasonic growth parameters in nonaddicted fetuses. Head and abdominal circumference data were used to evaluate the fetuses according to growth pattern. With this system of scoring, subtleties of asymmetric versus symmetric intrauterine growth retardation become apparent. In addition, birth weights of addicted infants were compared with birth weights of nonaddicted infants. The results suggest that, although statistically significant differences in birth weights cannot be demonstrated, abnormal growth of the addicted fetuses does occur. Addicted fetuses show a greater proportion of biparietal diameter and abdominal circumference values below the 50th and 25th percentiles than nonaddicted fetuses, and addicted fetuses more frequently exhibit intrauterine growth retardation patterns. These data suggest that it is fruitful to study these infants with near-normal size but with abnormal intrauterine growth patterns.

BPD measurements were obtained from 107 white and 91 black normal gravid women, with established dates, between weeks 16 to 40 of pregnancy. The sonar methodology used is uniform, employing nonpersistent image scanning with electronic calipers. It is noted that the BPD percentile growth patterns derived from these racially different fetuses are alike. Similarly, the fetal age distributions corresponding to white vs. black fetal BPD's show minor differences. From a clinical standpoint, therefore, one percentile curve is constructed for both populations. It is concluded that the BPD differences observed in the currently used growth curves, reported by different investigators, are related to nonuniformity in sonar BPD methodology.

Serial BPD readings were obtained from 142 normal parturients, with established dates, between 20 to 40 weeks of pregnancy. It is noted that fetal BPD's can be separated into one of three percentile rankings: large (i.e. above the seventy-fifth percentile), average (i.e. twenty-fifth to seventy-fifth percentile), and small (i.e. below the twenty-fifth percentile). In addition, it is shown that, under normal conditions, fetuses intially placed in any one of these cephalic levels will continue to grow within the confines of the same percentile range. This biologic phenomenon has not been previously reported in human fetal growth. It is important because it leads to a closer prediction of fetal age and a better assessment of neonatal weight and outcome.

Data from previous studies have suggested that birth weight prediction was enhanced by using formulas specifically derived from preterm fetuses. However, no prospective comparison of different formulas was performed. We obtained ultrasonic data on 61 pregnancies at risk for preterm delivery with a gestational age of 29.0 +/- 3.0 weeks (mean +/- SD). In all women birth weight was predicted within 7 days of delivery. Of the 61 pregnancies, 49 (80%), 41 (67%), 30 (49%), and 17 (28%) weighed less than 1750, 1500, 1250, and 1000 gm, respectively; 14 published formulas were compared for accuracy in predicting birth weight in these four categories. The formulas with the smallest absolute mean percent errors incorporated head and abdominal circumferences and femur length. The formula of Weiner et al., derived from low birth weight infants, produced the smallest absolute mean percent error and SD, 10.9% +/- 7.9%; this error was further reduced to 7.7% +/- 6.5% in infants weighing less than 750 gm. These findings suggest that birth weight in the preterm fetus is best predicted by a formula targeted to such a population.

We present our initial experience in developing a chorionic villus sampling program at Northwestern University. In phase 1, we performed chorionic villus sampling in 58 patients prior to elective first-trimester abortion, assessing the reliability and reproducibility of obtaining adequate villus samples and performing cytogenetic analysis by means of both the direct and culture methods. Specimens were categorized according to quality: class I, multiple identifiable villi (n = 20); class II, few villi or villi mixed with decidua (n = 15); class III, no villi (n = 23). There was a positive trend between operator experience, amount of villi obtained, and quality of cytogenetic preparations. In March, 1984, we received Institutional Review Board approval to perform chorionic villus sampling in continuing pregnancies (phase 2). Among the first 20 cases we found two abnormalities (47,XY, + 13; 45,X). The remaining 18 pregnancies were continuing. Recommendations are made for developing a chorionic villus sampling program.

Among 1,613 women studied with routine ultrasonography prior to genetic amniocentesis at Northwestern University Medical School, 25 of 26 multiple gestations were detected. Sampling of fluid from both amniotic sacs was requested by 20 women with twin gestations in which both fetuses were ultrasonographically determined to be viable and of normal size. Fluid was obtained successfully from both amniotic sacs in 19 of 20 cases. The conclusions are that (1) twin gestations can be reliably detected by the use of routine ultrasonography, (2) both amniotic sacs can usually be sampled, and (3) the complication rate appears to be minimal to the patient and the fetuses, although the sample size is still small.

Real-time imaging is generating a wave of enthusiasm among professionals engaged in the assessment of fetal health by biophysical means. In this report the reproducibility and accuracy of biparietal diameters (BPD’s) obtained by real-time imaging are examined in depth. In addition, comparisons are made between BPD’s obtained by real time and by both gray-scale and B-scan sonography. It is shown that BPD’s obtained by real-time imaging correlate with true BPD’s of neonates (delivered by cesarean section) only if (1) the width of skull tables on Polaroid photographs are 3 to 5 mm. and (2) the measurements are obtained from the outer aspects (O-O) of the cephalic contour traced on Polaroid photographs. BPD’s measured from the outer to the inner (O-I) cephalic points are smaller than the true BPD’s of neonates by an average of 3.8 mm.—the difference is statistically significant, P

Fetal facial reactions and response decrement patterns to external noise stimulation were studied to characterize normal fetal neurobehavior in the third trimester. Response decrement, or habituation, is thought to reflect higher central nervous system function. Two hundred women with uncomplicated pregnancies, who were subsequently delivered of healthy infants at term, were studied between 26 and 41 weeks' gestation. After ultrasound views of the fetal face were obtained, a vibratory acoustic stimulus was applied repetitively to the maternal abdomen near the fetal head. Response decrement was defined as cessation of all components of the facial reaction, except eye blinking, over two sequential stimuli. Three response patterns were scored: (1) no startle, (2) startle without response decrement, and (3) response decrement by 12 stimuli. Whereas only 53% of fetuses between 26 and 27 weeks displayed startle reaction, all fetuses displayed startle responses by 28 weeks. As gestational age advances, an increasing number of fetuses exhibit response decrement, from no decrement at 26 to 27 weeks to 100% decrement at 40 to 41 weeks. A maturation of neurobehavioral response patterns takes place in normal third-trimester pregnancies. Response decrement testing may be a useful tool for in utero neurologic evaluation.

Previous studies have demonstrated diminished ultrasonic fetal growth parameters in women delivering preterm. In this study, we tested the following hypothesis: In pregnancies complicated by spontaneous preterm labor, 1) unsuccessful tocolysis is likely to be associated with diminished fetal growth, and 2) successful tocolysis is likely to occur when fetal growth is normal. Ultrasound examinations were performed in 78 pregnancies complicated by preterm labor before 35 weeks' gestation. Tocolysis was attempted unless contraindicated or unless cervical dilatation was advanced (4 cm or greater). Pregnancies delivering before 36 weeks' gestation were compared with those delivering after this gestational age. Among the 48 pregnancies delivered before 36 weeks' gestation, a significantly greater proportion had ultrasonic growth parameters lower than normal values at corresponding gestational ages. In contrast, those pregnancies that had successful tocolysis and delivered near term demonstrated a normal distribution of ultrasound growth parameters. In pregnancies complicated by preterm labor, ultrasonic documentation of diminished fetal growth may identify the subgroup at increased risk for preterm delivery.

We present the percentile ranks of sonar fetal abdominal circumference (AC) measurements from 18 to 41 weeks' gestation. The ACs are derived from both longitudinal and cross-sectional ultrasonic studies of 200 low-risk pregnant women. The reproducibility of sonar AC falls within 2% of the mean value; this variation permits antenatal distinction of the fetus with a small AC (less than twenty-fifth percentile) or large (greater than eightieth percentile) reading. The fetal AC measurements add another dimension to the interpretation of cephalic growth, particularly in identifying macrosomic fetuses as well as those who are either asymmetrically or symmetrically undergrown. Additionally fetal AC measurements are useful as adjuncts to the diagnosis of hydrocephalus by quantitating the difference between cephalic and body size. In the presence of fetal ascites the AC also can be used to assess the severity and progression of the abnormality.

To test the applicability of equations for fetal weight estimations in a group of fetuses suspected of being large for gestational age, real-time ultrasound measurements of fetal biparietal diameters and abdominal circumferences were obtained for 34 fetuses of diabetic mothers. In the first phase of the study the accuracy in the prediction of weight was assessed with use of two known equations. In the second phase, biparietal diameter, abdominal circumference, and actual birth weight data of the 34 study fetuses were used as independent variables to determine the best-fitting equation for relating estimated fetal weight (EFW) to biparietal diameter (BPD) and abdominal circumference (AC); this equation is log (EFW) = 0.02597 AC + 0.2161 BPD - 0.1999 (AC X BPD2)/1000 + 1.2659. The standard deviation of differences is 322.26 gm and multiple R = 0.781. In the final phase the reliability of this equation was compared to those of Thurnau and Shepard in 34 additional fetuses of diabetic gravid women. The data suggest that in these fetuses suspected of being large for gestational age the weight estimates calculated at or near term may be enhanced if predictive equations are formulated specifically from the data for such fetuses.

We examined biparietal diameter, abdominal circumference, and birth weight in 148 preterm infants to assess fetal growth. A statistically significant proportion of preterm fetuses had biparietal diameter and abdominal circumference values below the fiftieth and tenth percentile levels as compared with that expected in normal fetuses. Similarly, birth weight of infants in the study fell significantly below the fiftieth and tenth percentiles relative to Brenner's curve. We corclude that diminished fetal growth is associated with early delivery secondary to preterm labor or preterm premature rupture of membranes or both. Additionally, since biparietal diameters in preterm fetuses are smaller than those of normal fetuses the prediction of gestational age by cephalometry should be advanced by 7 to 10 days.

The diagnosis of fetal hydrocephalus based on dilation of the ventricular system presents a broad range of management decisions. The options are presented and a case of Dandy-Walker syndrome managed by fetal ventriculoamniotic shunt placement is presented as an example. Under ultrasonic guidance, a shunt was placed at 30 weeks' gestation by later newborn Dubowitz examination. Delivery was delayed for five weeks, one to two weeks following probable shunt malfunction, after achieving fetal lung maturation. Follow-up six months after definitive neonatal ventricular shunting and three weeks after shunt revision revealed a socially active male infant with a motor development index of 87 and a psychomotor development index of 95. Potential advantages of fetal surgery including achievement of term gestation are presented. Proposed guidelines for determining the benefit of such procedures are also presented.

The ultrasonic abdominal circumference (AC) measurement is one of the essential parameters used for assessment of fetal status. Whereas the AC was traditionally derived by static equipment, dynamic scanners are presently used for that purpose. In this study, the AC values obtained by two gray-scale ultrasonic imaging modalities (static and dynamic) were compared; the differences between the mean AC measurements were not statistically significant. Additionally, when the outline of the AC in a fetus near term was larger than the sonic field displayed by dynamic equipment, the partially incomplete boundary could be “filled in” without affecting the accuracy of the result.

This report sought to determine whether estimates of fetal weight are enhanced by using ultrasonographic formulas targeted to the large-, appropriate-, and small-for-gestational-age fetus in both preterm and term pregnancies. Ultrasonographic fetal measurements from 575 singleton pregnancies were obtained within 7 days of delivery. The first 194 fetuses were classified into three groups on the basis of the growth percentile rank of the abdominal circumference (greater than or equal to 90%, greater than 5% and less than 90%, and less than or equal to 5%). Regression analyses were performed to generate three formulas for estimating fetal weight on the basis of the following: Gestational age (weeks) + Head circumference (cm) + 2 x Abdominal circumference (cm) + Femur length (cm). This mathematic model allowed formulation of accurate and concise tables relating the sum of these measurements to estimated birth weight. The accuracy of these formulas was then prospectively compared, first, with the formula published by Hadlock et al. (in 32 large-, 279 appropriate-, and 70 small-for-gestational-age fetuses) and second, with the formula of Weiner et al. (in 82 preterm fetuses). The difference between actual and estimated birth weights generated by the three study formulas had no systemic error (t test, p greater than 0.05). Cumulatively, there was a statistically significant reduction of random error in the birth weight estimates by use of the three study formulas versus the best single formulas of Hadlock et al. (2 SD reduced from 21.6% to 19.8% and absolute 2 SD reduced from 15.6% to 12.2%). Additionally, the three study formulas resulted in a statistically significant reduction in the absolute 2 SD error compared with the best formula by Weiner et al. in fetuses less than or equal to 34 weeks' gestation (2 SD reduced from 19.1% to 13.6%).

We report the outcomes of 95 expectantly managed cases of placenta previa; all were diagnosed after 21 weeks' gestation. Patients at risk for preterm delivery because of hemorrhage or preterm labor received aggressive care, including multiple transfusions, volume expansion and tocolytic therapy, and amniotic fluid surfactant determinations, to achieve the goal of delivery at 37 weeks' gestation with mature fetal lung function. We present guidelines for outpatient management and double setup examination prior to delivery. The role of ultrasound in diagnosis (three asymptomatic cases; 13 cases with preterm labor) and serial placental localization to determine the timing, route, and place of delivery is presented. Eighty-six percent of 19 infants born weighing less than 2500 gm were managed expectantly. Hemorrhage was the determinant in delivery timing in 50 cases. All four deaths were neonatal with birth weights less than 2200 gm. This is the lowest perinatal mortality rate (4.2%) published to date. Use of this aggressive approach is particularly suitable for patients cared for in a teritary center.

This case report describes the antenatal diagnosis of a fetal pulmonary anomaly. Early detection afforded detailed parental counseling and prompt neonatal diagnosis and treatment.

It recently has been shown that the sonar predictive accuracy of gestational age can be markedly enhanced by separating fetuses into one of three cephalic growth patterns, namely, large, average, and small. In this way it becomes possible to adjust fetal age in relation to biparietal diameter (BPD) growth. In this report we are defining the application of a growth adjusted sonographic age (GASA). Additionally, we are introducing a table which simplifies the assignment of GASA on a routine basis.

The ultrasonically derived fetal abdominal circumference is one of the essential parameters used to predict birth weight, assess fetal growth, and follow the evolution of fetal ascites. Growth curves relating abdominal circumference to gestational age have been reported for directly measured abdominal circumferences. However, none have been reported for abdominal circumferences calculated from measurements of fetal abdominal diameters. In this report, 197 normal fetuses ranging from 18 to 41 weeks' gestation are studied. The validity of 468 abdominal circumferences calculated from fetal abdominal diameters is tested by comparing the data with a similar number of direct abdominal circumference measurements obtained by a digitizer. From 18 to 41 weeks' gestation, directly measured fetal abdominal circumferences are significantly larger than fetal abdominal circumferences calculated from abdominal diameters (P less than .0001). The authors conclude that clinical management decisions based on abdominal circumference data are predicated on the use of appropriate abdominal circumference and/or abdominal diameter growth curves.

Based on ultrasonographic mensuration, a number of equations have previously been devised for the purpose of estimating fetal weights. The objective of this study was to develop a mathematical equation that is simple, accurate, and easy to use when applied to preterm or low-birth weight fetuses (less than 2,500 gm). Real-time ultrasound measurements of fetal biparietal diameters (BPDs) and abdominal circumferences (ACs) were obtained in 62 pregnant women within one week of premature delivery. Mean gestational age and mean birth weight +/- SD for this study group of neonates were 28.5 +/- 3.5 weeks and 1,135 +/- 343 gm, respectively. With the aid of computer analysis, a simple regression equation was derived: EFW = (BPD x AC x 9.337) - 229. When predicted estimated fetal weight (EFW) was compared with actual birth weight (ABW), multiple regression analysis demonstrated a correlation coefficient (R) of 0.957. Preliminary results on 19 patients of a prospective study showed an absolute mean difference between the computed EFWs and the ABWs to be within 7.0% of ABW (70 gm/kg of ABW). The standard deviation of the difference was 9.3% of ABW (93 gm/kg of ABW). Based on these data, this simple equation appears to be clinically reliable and easy to use when estimating weights of preterm or low-birth weight fetuses of less than 2,500 gm.

In this report the predictive value of ultrasonic targeted imaging for fetal anomalies (TIFFA) is defined. Six hundred fifteen pregnant women at high risk for birth defects were scanned from January, 1980, to December, 1983. Follow-up evaluation was available on 569 fetuses. The pregnancies were classified into five groups according to the indications used for ultrasonic targeted imaging studies. The largest number of women were placed in group 1 and were referred because of a variety of abnormalities in previous or ongoing pregnancies. The women classified in the other four groups were examined because of maternal or fetal reasons related to specific craniospinal (29%), urinary (7.9%), gastrointestinal (6.7%), and skeletal (3.7%) defects. In our series the predictive values of abnormal and normal ultrasonic targeted imaging studies were 95% and 99%, respectively. A detailed breakdown of the accuracy of ultrasonic targeted imaging in relation to each anatomic category is presented; these data are useful in counseling gravid women with anomalous fetuses.

The rhesus-sensitized fetus with the worst prognosis is one with early onset of hydropic changes. Percutaneous umbilical blood sampling now enables access to the fetal circulation and thereby allows more precise evaluation of fetal anemia and direct intravascufar transfusion. A variation of this technique was used in three pregnancies complicated by fetal pericardial effusion, scalp edema, and abdominal ascites before 26 weeks' gestation. Twelve ultrasound-guided percutaneous transfusions of 30 to 85 ml packed red blood cells were administered into the umbilical cord at its placental insertion. In each fetus the hydropic changes completely resolved and pregnancy outcome was successful. Neither adjunctive therapy with digoxin or Lasix nor exchange transfusions were used. Percutaneous umbilical transfusions appear to have the potential to improve the prognosis for the severely isoimmunized fetus.

Repetitive determinations of increasing fetal biparietal diameter were made in 8 pregnant rhesus monkeys with B-scan ultrasound. There was a plateau in skull growth after 120 days' gestation. Amniotic fluid aspirated at 115, 132, 148, and 155 mean days' gestation was analyzed for lecithin and sphingomyelin concentrations. Gestational ages were known to ± one day in all fetuses. Peak levels of lecithin appeared in amniotic fluid at 148 days of pregnancy, with a lecithin:sphingomyelin ratio of 2.3:1, partly because of decreased sphingomyelin. Fetal size does not appear to be an influence upon lecithin secretion into amniotic fluid in the rhesus monkey. Two animals with glucose intolerance induced by Streptozotocin ∗ ∗The Upjohn Co., Kalamazoo, Michigan. showed decreased phospholipid values in amniotic fluid and a mean lecithin:sphingomyelin ratio of 1.2:1 at 142 days' gestation. Acetone-precipitated lecithin was found to be an increasing fraction of total lecithin during progression of pregnancy.

Study of placental transfer of 14 C-thiouracil in pregnant rats from the tenth through the twentieth day of pregnancy showed a rapid and facile transfer of the compound throughout pregnancy. The latter stages of pregnancy displayed increasing radioactivity in the fetus with time, presumably indicating increasing incorporation into the fetal thyroid.

Both retrospective studies of idiopathic aborters, as well as prospective studies of normal couples, have shown reduced fertility among couples sharing HLA antigens. However, the effects of maternal-fetal histocompatibility on surviving embryos are largely univestigated. We thus prospectively studied 53 healthy, fertile women whose timed pregnancies were verified within 21 days of conception. Maternal-fetal histocompatibility status was determined for HLA-A,-B, and -DR locus antigens. Fetal growth rates were monitored by ultrasound at 8, 12, and 20 weeks gestation. Neonates were weighed, measured (birthlength, chest circumference, head circumference), and examined within 72 h of delivery (116 major and minor anomalies) in standardized fashion by one of two geneticists. Although no significant differences were found between infants compatible and incompatible at the HLA-A or HLA-B locus, significant differences were observed between HLA-DR compatible and incompatible infants for sex ratios (p less than .003) and minor anomaly rates (p less than .05). Although differences in mean birthweights between HLA-DR compatible and incompatible infants were not significant in this sample, HLA-DR compatible infants were on average 200 grams smaller than HLA-DR incompatible infants. We interpret these findings as evidence for selection against histocompatible fetuses throughout gestation, particularly with respect to HLA-DR compatibility. Potential immunologic and genetic mechanisms are discussed.

Sonar biparietal diameter, head circumference, and abdominal circumference percentile values obtained late in the third trimester were compared with birth weight percentile (relative to dates) in 147 diabetic mothers and 40 control fetuses of nondiabetics. Estimates of fetal weight by the method of Shepard et al were also calculated from these sonar data and compared with birth weight percentile. Abdominal circumference values greater than the 90th percentile correctly predicted macrosomia (defined as birth weight greater than 90th percentile) in 78% of cases. Biparietal diameter and head circumference percentiles were significantly less predictive of macrosomia. When analyzed in a similar manner, estimated fetal weights greater than the 90th percentile correctly predicted macrosomia at birth in 74% of cases. However, when both the abdominal circumference and the estimated fetal weight exceeded the 90th percentile, macrosomia was correctly diagnosed in 88.8% of pregnant women with diabetes mellitus.