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OBJECTIVE: The null hypothesis was that offspring of women undergoing first-trimester chorionic villus sampling do not experience a rate of birth defects exceeding background rates. STUDY DESIGN: Follow-up information regarding major malformations was prospectively sought on offspring of 4105 women undergoing first-trimester chorionic villus sampling from nine centers participating in a collaborative study with the Cook obstetrics and gynecology catheter. These data were compared with data from the Collaborative Perinatal Project and other registries. RESULTS: A total of 84 offspring with major malformations was identified (2.36%). Compared with background rates, there was no increase in the incidence of total malformations or specific malformations (including limb reduction defects) in the subjects. One institution experienced all three limb reduction defects in this series; the probability of this occurring by chance alone is CONCLUSION: Chorionic villus sampling was not found to result in an increase in major birth defects or in specific categories of birth defects in this series.

OBJECTIVE: The purpose of our study was to thoroughly investigate the risk factors of uterine rupture in patients undergoing trial of labor after cesarean section. STUDY DESIGN: We conducted a case-control study of 70 patients with prior cesarean delivery with uterine rupture during trial of labor between January 1983 and June 1990. The risk factors of uterine rupture were identified, and the estimates of the relative risks were reported. RESULTS: The risk of uterine rupture was increased in patients who had an excessive amount of oxytocin, who had exeprienced dysfunctional labor, and who had a history of two or more cesarean deliveries. Epidural anesthesia, macrosomia, history of successful vaginal delivery after cesarean section, unknown uterine scar, and history of cesarean delivery because of cephalopelvic disproportion were not associated with uterine rupture. CONCLUSIONS: We recommend that all patients with a history of cesarean delivery be observed closely for progression of labor. Recognition of an active-phase arrest disorder, despite adequate augmentation with oxytocin, requires operative delivery.

The purpose of this study is to evaluate the use of transvaginal ultrasound in the diagnosis of placenta previa and to assess the risk of bleeding secondary to the placement of the vaginal transducer. Thirty-eight patients with an estimated gestational age equal to or greater than 26 weeks and the diagnosis of suspected placenta previa gave their consent and were randomized to two groups. Randomization was stratified by patient weight and anterior or posterior placental location. Group 1 (n = 20) had complete obstetric ultrasounds using linear and sector transducers. Group 2 (n = 18) had similar examinations followed by transvaginal ultrasound scans. Patients were rescanned to follow placental location and fetal growth parameters. On abdominal ultrasound, the posterior placenta (n = 17) was often shadowed by fetal parts. The ease of placental visualization was rated on a four-point scale with 1 being the clearest. The mean clarity score for posterior placentas on abdominal ultrasound in Group 2 was 1.6 and on transvaginal ultrasound was 1.0, p < 0.04. The use of transvaginal ultrasound consistently revealed greater clarity of diagnosis in these patients. No patient in either group experienced increased vaginal bleeding following the scanning sessions. Transvaginal ultrasound was most beneficial for those patients with posterior placenta previas because of increased clarity of diagnosis, decreased time of scanning, and no increased incidence of hemorrhage.

Objective: The purpose of this study was to determine the value of discordant morphometric measurements as identifiers of Down syndrome by evaluating the relationship of biparietal diameter, femur length, biparietal diameter/femur length ratio, and cephalic index between a group of fetuses with trisomy 21 and a control population. Study Design: Biometrie measurements from 48 fetuses with trisomy were reviewed and compared with 107 normal fetuses of similar gestational age. Data were analyzed in 2-week gestational age intervals to determine the effect of gestational age on ultrasonographic detection of Down syndrome. Outcome measures were subject to least-squares linear regression and the t test for analysis. Results: A positive relationship between abnormal morphometric measurements and fetuses with Down syndrome was detected but only during specific weeks of pregnancy. Conclusion: Although it appears that biometric measurements may be useful for Down syndrome, further study is needed before its widespread introduction into clinical practice.

Controversy surrounds the issue of recommending cytogenetic studies in second-trimester fetuses with fetal choroid plexus cysts. To assist in clarifying this issue, a prospective study was designed to describe the association between fetal choroid plexus cysts and aneuploidy in a large population. During a 3-year period 7350 women at 15 to 22 weeks' gestation underwent an ultrasonographic evaluation. Fetal choroid plexus cysts were diagnosed in 71 (0.96%) of these pregnancies. Sixty-two of the 71 patients elected to undergo amniocentesis. An abnormal karyotype was identified in four (6.4%) of these fetuses. One fetus had trisomy 21, and three fetuses were diagnosed with trisomy 18. These data indicate that it is reasonable to offer genetic counseling and cytogenetic studies in those patients identified as having a fetal choroid plexus cyst.

Daily transvaginal ultrasound (US) scanning of the ovaries to assess follicular development and daily blood sampling were performed on 19 Norplant (Leiras, Turku, Finland) subdermal contraceptive implant users who had regular menstrual cycles and on 10 normally cycling women. Three groups were identified in the implant users based on US finding. Six (31.6%) of the implant users had US findings that were consistent with a normal ovulatory pattern. However, their mean peak luteinizing hormone levels and peak midluteal phase progesterone (P) levels were significantly lower than control values. Eleven (57.9%) users had persistent follicles, and 2 users (10.5%) had no follicular development. These data suggest that after 2 to 4 years of use, about one third of Norplant users with regular bleeding patterns may ovulate but most have deficient luteal P levels. In this small study, the presence of persistent follicular enlargement in implant users was common.

Sonographic technology has given the prenatal diagnostician the ability to accurately visualize fetal malformations. This article demonstrates the currently available capability of applying sonographically derived information concerning fetal dysmorphology to our knowledge of genetic disorders and syndromes. As a result, there can be a significant improvement in the management and counseling of these patients. After an initial discussion of normal embryology, principles of abdominal ultrasonography are discussed and applied to the following anomalies: omphalocele, gastroschisis, diaphragmatic hernia, duodenal atresia, other intestinal atresias and stenoses, renal anomalies, and obstructive uropathies.

A general description and discussion of the normal head and spine, and major fetal anomalies has been presented. It is important to remember that there can be wide variability in the structural findings noted in the fetus with ventricular dilatation or abnormal cerebellar development. If an abnormality of the fetal head and spine is seen, it is important to carefully assess other areas of fetal anatomy because of the increased likelihood of coexisting anomalies. Because of the increased incidence of chromosomal abnormalities, evaluation by percutaneous umbilical blood sampling, amniocentesis or placental biopsy is recommended for all structural abnormalities of the fetal head and spine. The best clinical approach for the ultrasonologist is to accurately describe and quantify the abnormalities for geneticist, pediatrician and or neurosurgeon to discuss the prognosis. Accurate evaluation of the type, location and extent of a neural tube defect is important to enable the family to understand possible outcomes of the pregnancy.

The purpose of this study is to evaluate models for the prediction of birth weight in fetuses suspected of being macrosomic. A total of 141 patients with standard measurements of the head, abdomen, and femur were studied. Linear regressions were performed with single parameters, squares, and all possible cross products in the generation of models with log (birth weight) and birth weight as dependent variables. These models were then compared with a group of previously published equations. Clinically, all models performed poorly. However, two models were significantly less accurate in the prediction of birth weight (p ≤ 0.05). The best results were obtained by equations that used abdominal circumference and femur length measurements. There was no improvement in models that contained log (birth weight) or birth weight as dependent variables or models with complex variables such as squares or cross products of measured parameters. In conclusion, when evaluating patients at risk of macrosomia, the best estimates of fetal weight can be obtained by models that contain abdominal circumference and femur length. (Ann J OBSTET GYNECOL 1990;162:238-42.)

To delineate any possible prognostic indicators, we reviewed the ultrasonographic and nonmorphometric findings in 19 antenatally diagnosed cases of nonimmune hydrops fetalis in which it was chosen to continue the pregnancy. Thirteen fetuses died and six survived. Of all parameters examined, including associated anomalies, abnormal karyotype, location of serous fluid, anemia, and possible cause of nonimmune hydrops fetalis, the most sensitive prognostic indicator was the real-time-directed M-mode echocardiographic measurement of the biventricular outer dimension in diastole. All fetuses with biventricular outer dimensions greater than 95% died, whereas all but one with normal biventricular outer dimensions had resolution of nonimmune hydrops fetalis and survived. This was highly significant (p less than 0.001) with the predictive value of a normal biventricular outer dimension being 86% and the predictive value of an enlarged biventricular outer dimension being 100%.

Our purpose was to evaluate an antepartum testing program based on twice-weekly nonstress testing and amniotic fluid evaluation in pregnancies complicated by diabetes mellitus and to weight the test components in the prediction of fetal distress requiring cesarean delivery.During the 4-year period of 1987 through 1990, 2134 women with pregnancies complicated by diabetes underwent antepartum testing. Of these 1501 women (class A1, n = 505; A2-diet, n = 305; A2-insulin, n = 580; B, n = 71; C to D, n = 29; R to F, n = 11) were delivered within 4 days of their last test. Categoric analysis of data was performed according to diabetic class, fetal heart rate results, and the presence of decreased, normal, or increased amniotic fluid assessment. A univariate logistical regression was first conducted with cesarean delivery for fetal distress as outcome variable by use of the following variables: fetal weight and sex, diabetic class, gestational age at delivery, presence of additional indications for antepartum testing, largest vertical pocket, amniotic fluid index (summation of the four quadrants of the largest vertical pocket), nonstress test reactivity (two accelerations ofor = 15 beats/min of 15 seconds' duration), presence of decelerations (or = 15 beats/min for 15 seconds) during the nonstress test, and the interactions of the nonstress test with deceleration, largest vertical pocket, and amniotic fluid index. Multivariate analysis was then applied to predict the best model.No stillbirths occurred within 4 days of the last antepartum test. However, the corrected stillbirth rate of the entire tested population was 1.4 per 1000. Eighty-five women required cesarean delivery for fetal distress. The factors most predictive of cesarean delivery for fetal distress (p0.05, odds ratio and 95% confidence interval) were a deceleration (3.60, 2.14 to 6.06), nonreactive nonstress test (2.68, 1.60 to 4.49), and the interaction of both a nonreactive nonstress test and decelerations (5.63, 2.67 to 11.9). Amniotic fluid assessment by largest vertical pocket or amniotic fluid index were not statistically significant. The multivariate analysis selected the interaction of nonstress test and deceleration as the best significant predictor for cesarean delivery for fetal distress.An antepartum fetal surveillance program using twice-weekly nonstress test and fluid index assessment in pregnancies complicated by diabetes was successful in preventing stillbirth. The absence of fetal heart rate reactivity and the presence of decelerations were predictive of the diagnosis of fetal distress in labor requiring cesarean delivery. Ultrasonographic assessment of amniotic fluid volume was not a significant predictor of fetal distress in labor in the diabetic pregnancy.

Objective The four-chamber view of the heart is an important component of the ultrasonographic examination of the fetus. However, during the second trimester of pregnancy the fetal heart cannot always be imaged in every patient. The purpose of this study was to ascertain the rate of successful imaging of the fetal heart during the second trimester and to determine factors that may influence imaging. Methods Seven hundred and nine second trimester fetuses were examined and an attempt was made to obtain the four-chamber and outflow tract views of the heart. Analysis included multiple logistic regression models of the main effects and interactions of ten candidate variables. Results The four chambers and outflow tracts were imaged in 643 fetuses (90.7%) and not imaged in 66 (9.3%). Fifty-two of 709 patients (7.3%) had had previous surgery. In the 52 patients with a history of previous surgery, the heart could not be imaged in 18 (34%). Six hundred and fifty-seven patients (92.7%) did not have previous surgery. Of this group, the fetal heart could not be imaged in 48 (7.3%). In only one fetus in which the heart could not be imaged was it because of fetal position. Three independent risk factors that influenced imaging of the fetal heart were gestational age, maternal adipose tissue thickness, and previous lower abdominal surgery. Increasing gestational age increased the probability of imaging the heart, whereas increasing adipose tissue thickness and a history of previous surgery decreased the probability of imaging the heart. Comments When the fetal heart cannot be imaged during the second trimester, these factors should be identified. Using data from this study, the gestational age at which the highest probability of imaging the heart can be determined if the thickness of the adipose tissue and a history of lower abdominal surgery are known.

This study examined whether there were differences between the umbilical artery systolic-diastolic (S/D) ratio and resistance index (RI) in patients with normal fetuses living at sea level (group I) and those living between 4,200 and 4,500 feet above sea level (group II). Linear regression demonstrated a significant association (P less than 0.001) between gestational age and the S/D ratio and RI for groups I (n = 100) and II (n = 128). Least-squares regression analysis demonstrated no significant differences in slopes or intercepts between groups I and II. The results would suggest that altitude, up to 4,500 feet above sea level, does not affect umbilical artery Doppler resistance in normal fetuses.

The error associated with regression analysis methods for the ultrasonographic estimation of fetal weight in the suspected macrosomic fetus, approximately 10%, is clinically unacceptable. This study was undertaken to evaluate the applicability of an emerging technique, biologically simulated intelligence, to this problem. One hundred patients with suspected macrosomic fetuses underwent ultrasonographic measurements of biparietal diameter, head and abdominal circumference, femur length, abdominal subcutaneous tissue, and amniotic fluid index. The biologically simulated intelligence model included gestational age, fundal height, age, gravidity, and height. The model was then compared with results obtained from previously published formulas relying on the abdominal circumference and femur length. The biologically simulated intelligence yielded an average error of 4.7% from actual birth weight, statistically better (p = 0.001) than the results obtained from regression models.

This study was undertaken to determine the incidence and associations of uterine rupture and dehiscence with an attempted vaginal birth after cesarean section. The charts from 137 patients who had uterine scar separation after a previous cesarean section from 1983 to 1989 were examined. Approximately 9.3% of the 119,395 women who were delivered in that interval had a prior cesarean section. Of those, 68.8% underwent a trial of labor with a 79.2% success rate. The uterine rupture rate in this latter group was 0.8%, while an additional 0.7% had a bloodless dehiscence. Bleeding and pain were unlikely findings with a uterine scar separation (3.4% and 7.6%, respectively). The most common manifestation of a scar separation was a prolonged fetal heart rate deceleration leading to operative intervention (70.3%). We conclude that, although the incidence of uterine rupture was low, the event is most often seen as an acute emergency. Prevention should be directed toward timely diagnosis and prompt management of labor dystocias. Staff and facilities for safe management of a uterine scar separation are a requisite for the conduct of a vaginal birth after previous cesarean section.

A case of a prenatally recognized hepatic mesenchymal hamartoma is presented and the literature reviewed. These tumors are benign and usually present in early infancy with symptoms that are related to the mass effect on adjacent organs. Radiologic methods used in the past to image this tumor include angiography and ultrasound. However, there is no specific radiologic finding, and, therefore, the diagnosis is usually made during surgery. Once the tumor is removed, the prognosis is generally good. With the increasing use of high resolution ultrasound in prenatal diagnosis, this rare tumor should be considered in the differential diagnosis of any multicystic mass found in the fetal abdomen. The recognition of a mass should then alert the physician to the need for early neonatal intervention.

Elevated systolic/diastolic ratios obtained by umbilical and uterine velocimetry have been used to predict adverse pregnancy outcome. We performed pretherapy umbilical and uterine velocimetry by means of continuous-wave Doppler ultrasonography on 92 patients who came for treatment in preterm labor. Fourteen (15.2%) and 12 (13%) patients had elevated uterine (greater than 2.6) and umbilical (greater than 3.5) systolic/diastolic ratios, respectively, and 9 (9.8%) patients had both ratios elevated. Overall 17 (18.5%) patients had at least one abnormal systolic/diastolic ratio. Patients with abnormal Doppler waveforms had a significantly shorter gestation, infants with lower birth weights, and a higher incidence of adverse pregnancy outcome as determined by meconium, cesarean section for fetal distress, low 1- and 5-minute Apgar scores, and days in the neonatal intensive care unit, compared with patients with normal systolic/diastolic ratios. There was no significant difference in the ability of uterine, umbilical, or combined velocimetry to predict preterm birth or adverse pregnancy outcome. Doppler studies in preterm labor patients may help to identify patients at increased risk for preterm birth and poor pregnancy outcome. Further studies are warranted to assess its usefulness in the evaluation of these patients.

We assessed the relationship between systolic/diastolic ratios as determined by umbilical velocimetry to fetal heart rate. Umbilical velocimetry was performed with continuous-wave Doppler ultrasound and systolic/diastolic ratios and fetal heart rate for the corresponding cardiac cycles were calculated in four groups of patients. Group 1 consisted of 30 patients undergoing antepartum fetal testing; systolic/diastolic ratios were found to be significantly lower (mean +/- SD, 2.0 +/- 0.15) during an evoked fetal heart rate acceleration with an artificial larynx than either before (2.4 +/- 0.14) or after the acceleration (2.35 +/- 0.10, p less than 0.01). In 20 patients with pyelonephritis (group 2), systolic/diastolic ratios were significantly lower during initial fetal tachycardia (1.6 +/- 0.21) as compared with those obtained after its resolution (2.1 +/- 0.12, p less than 0.08). In the 25 patients with chorioamnionitis in group 3, systolic/diastolic ratios were significantly higher during initial fetal tachycardia (1.4 +/- 0.21) than after its resolution (1.9 +/- 0.15, p less than 0.05). Twenty patients in labor (group 4) had 10 serial measurements at 1 to 2-hour intervals of systolic/diastolic ratio and FHR. Least-squares regression of each patient showed a negative slope that differed statistically from zero (p less than 0.05). There were no patients with elevated systolic/diastolic ratios greater than 3.0 in any group and all patients delivered fetuses appropriate for gestational age. These findings suggest an inverse relationship between systolic/diastolic ratio and fetal heart rate. Additionally, an alteration in fetal heart rate within the range studied does not itself produce abnormal ratios. Therefore normalization of the systolic/diastolic ratio for heart rate may be considered in clinical studies for statistical analysis and comparison but may have little practical or clinical relevance when the ratios are abnormal.

Analysis of computer-stored State of Missouri birth and death records over a 5 year period revealed 3,594 twin pregnancies (1.02% of all pregnancies), which accounted for 10.1% of the perinatal deaths. The mean birth weight according to weeks of gestation was computed for the pregnancies with no complications noted prior to labor and the perinatal mortality rate was determined. Complications of pregnancy were evaluated. Low birth weight appears to be the major factor in the elevated perinatal death rate in twin pregnancy, with a significant elevation of the perinatal death rate noted with labor prior to 36 weeks, any episode of hemorrhage, or premature rupture of membranes. A more liberal use of cesarean section currently shows no effect in altering the perinatal mortality rate. Programs are suggested to increase early detection and appropriate consultation and referral of multiple pregnancies in a statewide comprehensive effort to decrease the perinatal mortality rate in twin pregnancy.

Postterm antenatal fetal surveillance has traditionally begun at 42 completed weeks of gestation. However, recent data have shown that a significant percentage of cases of perinatal asphyxia occurs between 40 and 42 weeks of gestation. We compared the perinatal outcome of fetuses with antenatal surveillance beginning at 41 weeks to those starting at 42 weeks of gestation. The study groups consisted of 908 patients who began antenatal testing at 41 weeks and 352 who began testing at 42 weeks. Antenatal testing consisted of twice-weekly amniotic fluid assessments and nonstress tests (including evaluation for late and variable decelerations). Between 41 and 42 weeks, the group whose testing started at 41 weeks had an overall incidence of intrapartum fetal distress of 2.7%, no stillbirths, and no infants with major neonatal morbidity. Patients without antenatal testing who delivered between 41 to 42 weeks did not have a significantly increased incidence of fetal distress (3.3%; p = 0.07). However, this group had a significantly increased incidence of adverse outcomes (p less than 0.05), including three stillbirths and seven cases of major neonatal morbidity. Beyond 42 weeks, the group whose testing started at 41 weeks had a 2.3% overall incidence of fetal distress. This was significantly less (p less than 0.01) than the group whose testing started at 42 weeks (5.6%). Neither of the groups had any stillbirths or infants with major neonatal morbidity. These findings suggest that starting antenatal testing at 41 weeks of gestation may result in decreased postterm perinatal mortality and morbidity as well as a decreased incidence of intrapartum fetal distress.

Maternal immune suppression is a potentially significant adverse effect when betamethasone is used to hasten lung maturation of the fetus at risk for preterm delivery. However, increased incidence of infection has not been observed consistently after betamethasone treatment of pregnant women. This study was designed to determine if the cellular immune response to steroids may be modified during pregnancy in a way that would diminish the infection risk associated with steroid treatment. The effect of betamethasone on immunocytes among patients with preterm labor or in nonpregnant subjects were determined following administration of 12 mg of betamethasone intramuscularly. We measured serially the circulating leukocytes, lymphocytes, T lymphocytes, and their subsets. Measurements were also made of localized leukocyte mobilization to serum-filled skin chambers covering experimental inflammatory sites. Patients in preterm labor had increased WBC counts prior to treatment with betamethasone but no additional leukocytosis was induced nor was mobilization of leukocytes to the skin chambers decreased. Lymphopenia and depression of T cells was more transient among pregnant patients compared to nonpregnant. Thus, the pregnant patients studied had diminished or more transient potentially adverse immunocyte responses to betamethasone as compared to nonpregnant subjects.

Deoxythymidine kinase is present in human cells in two forms: the cytosolar form (fetal thymidine kinase) and the mitochondrial form (adult thymidine kinase). The activity of thymidine kinase isozymes in plasma of preterm and term newborns has been previously reported to be related to gestational age, and fetal thymidine kinase activity was reported to be undetectable after the thirty-ninth week of gestation. Our purpose was to determine if similar changes in the activity levels of the thymidine kinase isozymes could be demonstrated in late third trimester maternal plasma. A cross-sectional sample of 35 patients was studied from week 34 of pregnancy to delivery. Significant differences between fetal and adult thymidine kinase activity patterns were observed. Adult thymidine kinase activity remained relatively constant throughout the evaluation interval, while fetal thymidine kinase activity decreased with advancing gestational age. Regression analysis of gestational age by neonatal examination (GAPED) and fetal thymidine kinase revealed a linear relationship (fetal thymidine kinase = 0.380 - 0.00745 GAPED; R2 = 0.2944; standard estimate of error = 0.0350; p less than 0.0008). Comparison of fetal thymidine kinase activity in term and postterm pregnancy plasma revealed a significant difference (p less than 0.0159). Our findings indicate that deoxythymidine kinase activity can be measured in maternal plasma, may relate to the fetoplacental growth rate, and may be useful in differentiating between term and postterm gestations.

Ultrasonic evaluation has been suggested as a possible screening tool for early changes in ovarian morphology. This study uses transvaginal sonography to evaluate the ovaries in postmenopausal women who were scheduled for gynecologic surgery unrelated to adnexal disease. The findings of ultrasonic ovarian examination are compared with the findings at surgery and the pathologic evaluation of the ovaries. Nine (17.3%) abnormal ovaries were identified by ultrasonography and at surgery and were confirmed at pathologic examination. Among the abnormal ovaries there were one malignancy (10%) and two neoplasms with known malignant potential (20%). One ovary that was identified to have microscopic areas of Brenner tumor cells at pathologic examination was described as normal by both ultrasound and surgical evaluation. The sensitivity (90%) and specificity (100%) of vaginal sonography were the same as that of gross examination of the ovary at the time of surgery. We conclude that vaginal sonography is a reliable tool in the detection of early abnormalities in the postmenopausal ovary.

A case of prenatal sonographic detection of a posterior mediastinal cyst in an otherwise normal fetus is presented. Following surgical excision 5 days after birth, histological examination confirmed the cyst to be gastroenteric. The differential diagnosis and clinical value of prenatal detection are discussed.

The purpose of this study was to determine the efficacy of combining nonstress testing with ultrasound assessment of amniotic fluid volume for the antenatal evaluation of the postterm fetus. Postterm patients (884) were managed with amniotic fluid assessments and nonstress tests (including evaluation for variable and late decelerations) twice a week. There were no perinatal deaths or major neonatal morbidity. However, the antenatal testing sensitivity, specificity, negative, or positive predictive values were not improved by combining the two tests. Individually, amniotic fluid assessment was just as accurate a predictor of fetal well-being and was a significantly more sensitive test than the nonstress test. In addition, antenatal predictors of fetal distress and intrapartum signs of fetal distress were almost exclusively those reflective of umbilical cord compromise. These findings stress the importance of antenatal screening for signs of umbilical cord compromise as an early indication of potential fetal compromise. Although the results also suggest that amniotic fluid assessment is superior to the nonstress test, they do not conclusively support the use of amniotic fluid assessment as the sole parameter for postterm antenatal surveillance.

One hundred twenty-two images of fetal heads and abdomens were obtained by ultrasound. The head and abdominal circumferences and their ratios were determined by planimetry and by the ellipse method utilizing four different equations. The accuracy of these equations was assessed by regressing the circumferences and ratios obtained by the equations against those measured by planimetry. All equations were found to be equally accurate in calculating head and abdominal circumferences and the head-to-abdomen circumference ratio. Compared to planimetry, the ellipse method is more accurate in calculating circumferences than when calculating their ratio.

Seventy-eight singleton term neonates, delivered of women who were 35 years of age or older after chorionic villus sampling at 9 to 11 weeks' gestation, were compared with 1335 singleton control neonates delivered at term of mothers 35 years of age or older before the clinical application of chorionic villus sampling at our institution. No statistically significant differences were found in birth weight, crown-heel length, or ponderal index between control neonates and neonates delivered after chorionic villus sampling. The sample sizes necessary to detect a 5% difference in population means at an alpha error level of 0.05 and beta error level of 0.1 were calculated for the measured variables and achieved before analysis. This study suggests that patients undergoing chorionic villus sampling are not at increased risk for the development of decreased fetal growth or intrauterine growth retardation.

Umbilical and uterine artery velocimetry was performed using continuous-wave Doppler ultrasound (Angioscan III) in 60 patients in preterm labor. Peak-systolic/end-diastolic ratios were calculated according to previously described techniques. All measurements were made before tocolytic therapy was begun: magnesium sulfate (n = 40) or ritodrine (n = 20). The mean gestational age was 33.1 +/- 1.5 weeks (range 29 to 36 weeks). Twelve (20%) patients had elevated (greater than 2.6) pretherapy uterine peak-systolic/end-diastolic ratios, 10 (16.7%) patients had elevated (greater than 3.5) pretherapy umbilical peak-systolic/end-diastolic ratios, and in eight (13.3%) patients both ratios were elevated. In seven (58.4%) of the 12 patients with elevated uterine peak-systolic/end-diastolic ratios, six (60%) of the 10 patients with elevated umbilical peak-systolic/end-diastolic ratios, and five (62.5%) of the eight patients with both ratios elevated tocolytics failed and the women were delivered within 48 hours, compared with seven (14.6%) of 48, eight (16%) of 50, and six (13.0%) of 46 with normal ratios, respectively (p less than 0.05). We conclude that patients in preterm labor with elevated pretherapy uterine and/or umbilical peak-systolic/end-diastolic ratios are more likely to fail tocolysis therapy and be delivered preterm than those with normal ratios. It may therefore be useful to include umbilical and uterine velocimetry in the initial evaluation of preterm labor.

Maternal cell contamination of chorionic villi (CV) samples used for first trimester prenatal diagnosis can cause obvious and/or unrecognized diagnostic dilemmas. The purpose of this investigation is to assess the frequency of maternal cell contamination (MCC) in chorionic villus samples and to evaluate selected parameters which might predict where contamination is more likely to have occurred. Maternal lymphocytes, chorionic villi from ultrasonically directed transcervical catheter aspiration, and fetal tissue were obtained at 8–11 weeks gestation from 45 patients undergoing elective termination. Quinacrine (Q) banded metaphases were compared from duplicate direct preparations of chorionic villi; cultured chorionic villi, fetal fibroblast tissue cultures, and maternal lymphocyte cultures. Q-polymorphisms in metaphase chromosomes were 100 per cent concordant between fetal tissue and direct CV preparation. However, evidence for maternal cell contamination occurred in 13.1 per cent of cultured chorionic villi preparations where polymorphisms were found to be identical between maternal and cultured CV and both distinct from fetal tissue preparations. Where MCC was identified, it was noted that CV cell cultivation interval was prolonged (24.2±6.8 days) compared with non-contaminated cultures (14.1±4.4 days) (p

Images of 122 fetal heads and abdomens were obtained with ultrasound for the determination of head and abdominal circumferences. The profile shapes were characterized by the cephalic or abdominal index (D1/D2 x 100), D1 and D2 being the shortest and longest diameters of either the head or abdomen. The mean of the cephalic index was 79.1% +/- 5.2%, and that of the abdominal index was 89.1% +/- 7.0%. All equations were equally accurate in calculating head and abdominal circumferences regardless of the profile shape. Therefore, the simplest equation, (D1 + D2) x 1.57, should be utilized when calculating circumferences except in situations of extreme dolichocephaly.

The purpose of this study is to assess alterations in vascular resistance as measured by Doppler ultrasound in the postterm fetus. Forty-five postterm patients (greater than or equal to 287 days gestation by "good" dates) underwent Doppler velocimetry and calculation of systolic to diastolic (S/D) ratios of the umbilical, internal carotid, and uterine artery waveforms within 7 days of delivery. Patients were divided into two groups. Group 1 consisted of 26 patients with normal antepartum fetal surveillance that included reactive nonstress test and an amniotic fluid index (using the four-quadrant technique) equal to or greater than 5 cm. Group 2 consisted of 19 patients with antepartum compromise on the antepartum fetal surveillance tests. There was significantly greater (p less than .05) morbidity in group 2 compared to group 1 as judged by cesarean section for fetal distress (47% vs 15%), meconium at delivery (53% vs 4%), and 5-minute Apgar score less than 7 (30% vs 4%). There were no significant differences in the umbilical and uterine artery S/D ratios in the two groups, although patients in group 2 had significantly lower cerebral S/D ratios (3.6 +/- .5) compared to group 1 (4.4 +/- 0.4) (p less than .05). The ratio of cerebral to placental (umbilical) resistance in group 2 was significantly lower (1.1 +/- .3) compared to group 1 (1.8 +/- .3) (p less than .05). There was a low incidence of abnormal umbilical (greater than 3) and uterine (greater than 2.6) S/D ratios in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The purpose of this study was to determine whether an early third-trimester fetal abdominal circumference measurement can be used in patients with gestational diabetes to predict the presence or absence of macrosomia and labor dystocia at term. The predictive accuracy of a 30- to 33-week abdominal circumference measurement was tested, using the ninetieth percentile as the discriminant point. The study consisted of 201 patients with gestational diabetes who maintained weekly fasting glucose levels less than 100 mg/dl and 2-hour postprandial glucose levels less than 120 mg/dl with dietary management alone. The predictive accuracy of a 30- to 33-week fetal abdominal circumference measurement was 96.4% for ruling out macrosomia and 56.3% for predicting macrosomia. Patients with fetal abdominal circumference measurements greater than the ninetieth percentile at 30 to 33 weeks had a significantly increased incidence of cesarean section for failure to progress, shoulder dystocia, and birth trauma, whereas patients with abdominal circumference measurements less than or equal to the ninetieth percentile were at no greater risk than the general population. These results suggest that patients with non-insulin-dependent gestational diabetes with fetal abdominal circumference measurements less than or equal to the ninetieth percentile at 30 to 33 weeks are not at increased risk for macrosomia, cesarean section, or birth trauma at term, as long as their weekly glucose testing remains within normal limits. Efforts to decrease the incidence of macrosomia and its attendant risks should focus on those gestational diabetic patients whose fetal abdominal circumference greater than the ninetieth percentile at 30 to 33 weeks.

Systolic/diastolic ratios of umbilical velocimetry obtained with either continuous-wave or pulsed-wave Doppler ultrasonography have been used to assess downstream placental vascular resistance and fetal well-being. The purpose of this study is to compare the efficacy of systolic/diastolic ratios obtained by continuous-wave and pulsed-wave Doppler ultrasonography in the prediction of poor pregnancy outcome. Continuous-wave and pulsed-wave umbilical velocimetry was performed and systolic/diastolic ratios were measured in 200 high-risk pregnancies in the third trimester by use of Angioscan III and a General Electric RT 3600 scanner, respectively. A total of 165 study participants had normal systolic/diastolic ratios and 35 participants had elevated ratios (greater than 3.0) with both continuous-wave and pulsed-wave Doppler ultrasonography. Both methods identified 35 participants with abnormal ratios, and none of the women was misclassified by either method. The pulsed-wave and continuous-wave values for 35 participants with elevated ratios were 6.35 +/- 1.52 and 6.23 +/- 1.58, respectively; values for 165 participants with normal ratios were 1.95 +/- 0.40 and 1.96 +/- 0.41, respectively (not significantly different). Participants with elevated systolic/diastolic ratios within 7 days of delivery had significantly higher incidence of adverse pregnancy outcome as judged by small-for-gestational-age fetuses, presence of meconium at delivery, fetal distress in labor, cesarean sections and 5-minute Apgar scores less than 7. Fetuses with elevated ratios were delivered at an earlier gestational age (34 +/- 1.2 weeks), had lower birth weights (1422 +/- 151 gm), and spent more time in the neonatal intensive care unit (17.1 +/- 5.2 days), compared with fetuses with normal ratios (delivered at 38.5 weeks +/- 0.9 weeks, 3100 +/- 210 gm birth weights, and 2 +/- 0.2 days spent in neonatal intensive care units, respectively, p less than 0.05). We therefore conclude that continuous-wave and pulsed-wave Doppler ultrasonography produce similar results with regard to systolic/diastolic ratios in high-risk pregnancies, and either method appears to be a valuable adjunct in the surveillance of high-risk pregnancies.

The incidence of natally acquired Herpes simplex infections (HSI) has been estimated to be 1/7500 births, despite the fact that rates of asymptomatic shedding by pregnant women have been shown to be as high as 1/154. To investigate mechanisms which may explain the lower than expected incidence of clinical infection, amniotic fluid (AF) obtained during gestation and amniotic fluid and secretions (AF-S) obtained from the infants' mouths at delivery were tested for ability to neutralize HS. AF or AF-S were incubated with an equal volume of virus inoculum for 1 hr at 37°C. Neutralization of virus was assessed by reduction in expected plaque forming units (pfu). Maternal serum antibody was considered absent if the neutralization titer was