Impact of head-to-abdominal circumference asymmetry on outcomes in growth-discordant twins.

OBJECTIVE: Our aim was to evaluate head-to-abdominal circumference asymmetry as a marker for adverse outcomes in growth-discordant twins. STUDY DESIGN: We conducted a retrospective cohort study of asymmetric and symmetric twins with > or =25% growth discordance, comparing their outcomes with those in concordant symmetric twins. Growth was termed asymmetric on the basis of a head circumference/abdominal circumference ratio at > or =95th percentile on ultrasonography performed < or =4 weeks before delivery. RESULTS: We evaluated 572 twin pairs. Asymmetric discordant twins were more likely than symmetric concordant twins to be delivered at < or =34 weeks' gestation (57% vs. 27%), to require intubation (36% vs. 7%), to remain in intensive care >1 week (36% vs 3%), and to have an outcome composite that included respiratory morbidity, intraventricular hemorrhage, sepsis, or neonatal death (29% vs 6%), all P<.05. Symmetric discordant and symmetric concordant twins had similar outcomes. CONCLUSIONS: Discordant twins with head-to-abdominal circumference asymmetry have an increased risk of morbidity. Moreover, in the absence of asymmetry, outcomes are comparable among discordant and concordant twins.

Color flow mapping for myometrial invasion in women with a prior cesarean delivery.

OBJECTIVES: Our aim was to evaluate the utility of color flow mapping in the prediction of placental myometrial invasion in women with Cesarean delivery. METHODS: Ultrasound color flow mapping was performed on placental implantations in potential proximity to the hysterotomy scar. The smallest myometrial thickness was measured under the placenta to evaluate the degree of myometrial attenuation in this area and note was made of unusual vascular lakes. RESULTS: Two hundred fifteen women with placentas in proximity to the prior hysterotomy scar underwent color Doppler mapping. Of 20 women with placenta previa and Cesarean delivery, 15 had Cesarean hysterectomy for bleeding complications and nine had the pathological diagnosis of placental invasion. The measurement of <1 mm for the smallest myometrial thickness or presence of large intraplacental lakes was predictive of myometrial invasion (sensitivity 100%, specificity 72%, PPPV 72%, and NPV 100%). CONCLUSIONS: Color flow mapping predicted myometrial invasion when the smallest myometrial thickness was <1 mm and large intraplacental lakes were demonstrated.

The Ovarian Tumor Index predicts risk for malignancy.

BACKGROUND: Prediction of ovarian malignancy by ultrasonographic findings and patient age in the scenario of clinically suspected adnexal masses is a desirable goal. METHODS: Prospective evaluation of clinically suspected adnexal masses was performed with transvaginal ultrasound using real-time, Doppler velocimetry, and color-flow mapping. Continuous ultrasound variables included ovarian volume, the Sassone morphology scale, and Doppler determination of angle-corrected systole, diastole, and time-averaged velocity, in addition to patient age. The Doppler pulsatility index (PI), vessel location, presence of a diastolic notch, and echogenic predominance of the lesion, suggestive of dermoid, also were assessed. RESULTS: Of 244 women with follow-up, 214 had nonmalignant findings (85 of which were benign neoplasms), and 30 had malignant neoplasms. Age and all ultrasound continuous variables except systole were found to be statistically significant (P < 0.05) between patients with both malignant (N = 30) and nonmalignant masses (N = 214), as well as those with benign (N = 85) and malignant (N = 30) neoplasms. By adding the continuous measures (age [in years], ovarian volume [mL], and Sassone morphology scale [1-15]) and weighting other variables ([-10] x PI, central or septal location [+10], peripheral location [-10], and echogenic [-10]), a receiver operating characteristic curve was generated (area under the curve = 0.91), which was found to be discriminating, predictive, and able to replicate the more complex logistic regression model. Prediction of malignancy was generated from the population-based data of the current study. CONCLUSIONS: The Ovarian Tumor Index, which combines patient age with specific ultrasonographic markers, is an accurate method for predicting ovarian malignancy in the clinical scenario of suspected adnexal masses.

Accuracy of ultrasonic detection of the uterus in normal newborn infants: implications for infants with ambiguous genitalia.

Every year approximately one in 5000 babies is born with ambiguous genitalia, a condition that requires immediate sex assignment if possible. We investigated whether transabdominal ultrasonography with the use of a linear array high-resolution 7.5-MHz transducer would enhance the accuracy of detecting the uterus in the newborn. One hundred mothers who delivered normal, term infants (> 36 weeks and > 2500 g) gave their informed consent for the investigation. Each infant was placed in an unmarked bassinet, external genitalia were covered, and ultrasound examinations were performed by the same examiner (R.S.) who was blinded to the sex of the infant. The neonatal uterus was identified in 47 of 50 female infants (94% sensitivity) and the absence of a uterus was correctly predicted in 49 of 50 male infants (specificity 98%). The average length of the neonatal uteri 1 day after birth was 3.2 +/- 0.5 cm and the total volume was 3.5 +/- 0.9 cm3. An endometrial strip could be identified in 98% of neonatal uteri. We conclude that the use of the high-resolution 7.5-MHz transducer available in commercial ultrasound equipment is an accurate method for the detection of the neonatal uterus. Infants born with ambiguous genitalia who have a uterus will almost always be assigned the female sex. Infants with ambiguous genitalia but without a uterus will have male pseudohermaphroditism.

Ultrasound anthropometric reliability.

Method errors and reliabilities were estimated for seven sonographic measurements in pregnancies of 106 women examined between January and July 1989. Teams of two experienced sonographers replicated the following measurements: biparietal diameter (BPD), occipital-frontal diameter (OFD), anterior-posterior diameter (APD), transabdominal distance (TAD), and femur diaphysis length (FDL). Multilevel modeling procedures were used to estimate the variance components. Significant (p < 0.01) covariates in the fixed part of the model included an increase in error with greater parity, estimated menstrual age (EMA), and maternal abdominal wall thickness (taken at the umbilicus). Intraobserver reliability ranged from 85.2% (AC) to 99.3% (FDL); interobserver reliability ranged from 80.8% (TAD) to 92.4% (FDL). Method errors, describing the expected error for 68% of the measurements taken, ranged from 0.8 mm to 7.7 mm (intraobserver) and from 1.2 mm to 7.8 mm (interobserver). These results suggest that large error components should be considered in the interpretation of the reliability of ultrasonographically obtained measurements.

Subcutaneous tissue: to suture or not to suture at cesarean section.

OBJECTIVE: The null hypothesis for this investigation was that there was no difference in the frequency of wound disruption between women who had their subcutaneous tissues approximated with suture and those who did not during cesarean section. METHODS: During alternating months, consecutive women delivered by cesarean section either did (N = 716) or did not (N = 693) have their subcutaneous tissues closed with suture. All data were analyzed using chi square, Student's t-test, Fisher's exact probability test, analysis of variance, or logistic regression. RESULTS: A 32% decrease in the frequency of wound disruption was observed when subcutaneous tissues were brought into apposition with suture at cesarean section (P = 0.03). CONCLUSIONS: Closure of Scarpa's and Camper's fascia with suture during cesarean section significantly decreased the frequency of wound disruption in this population.

Megadose carbamazepine during the period of neural tube closure.

BACKGROUND: Analyses of the frequency of congenital anomalies among infants born to women who used carbamazepine during organogenesis have not yielded consistent results. Because the drug is used to treat epilepsy, any association is confounded by the underlying condition. CASE: A nonepileptic 44-year-old multigravid woman attempted suicide by ingesting 24 200-mg carbamazepine tablets (approximately 4.8 g). By last menstrual period and sonogram dates, the megadose occurred during the third to fourth week post-conception. Maternal drug levels were elevated above therapeutic ranges for 2 days. Maternal serum alpha-fetoprotein was elevated, and high-resolution fetal sonography demonstrated a large myeloschisis that was verified at autopsy. No family history of neural tube defects or any other malformations was reported by the patient. Megadose carbamazepine ingestion during the period of neural tube closure was the only known risk factor. CONCLUSION: Although no other published reports of megadose carbamazepine during pregnancy were located, the neural tube defect is consistent with the recently reported risks for congenital anomalies in infants born to women who used this anticonvulsant in therapeutic doses during pregnancy.

Nomograms for rapid estimation of intravascular intrauterine exchange transfusion.

Fetal exchange transfusion is complicated by the fact that vascular access must be maintained while the number of exchanges needed to achieve a desired post-transfusion hematocrit is calculated. A rapid method for estimating the number of exchange transfusions would greatly simplify fetal exchange transfusion for blood group isoimmunization. In this report, we present a graphic method for determining the number of exchange transfusions necessary to achieve a post-transfusion hematocrit of 45%, using a nomogram for 5- and 10-mL exchange transfusion volumes.

Prediction of discordant twins using ultrasound measurement of biparietal diameter and abdominal perimeter.

Prediction of twin birth weight discordancy was tested in 116 gestations using sonographic measurements of biparietal diameter (BPD) and abdominal perimeter. Abdominal perimeter measurement differences of 20 mm or greater were more sensitive and specific than BPD difference in detecting twins with dissimilar birth weights.

Endocrine studies in a pregnancy complicated by ovarian theca lutein cysts and hyperreactio luteinalis.

Severe virilization developed in a pregnant woman in association with the occurrence of theca lutein cysts and hyperreactio luteinalis of the ovaries. At term, maternal serum levels of androstenedione (58 ng/mL) and testosterone (20 ng/mL) were elevated massively; estrone (24 ng/mL) and estradiol-17 beta (23 ng/mL) levels were increased moderately. Maternal serum levels of human chorionic gonadotropin (hCG) just before delivery, 22,276 mlU/mL, though twice the mean for normal women at term, were within the normal range. The levels of androstenedione (1.06 ng/mL) and testosterone (0.26 ng/mL) in umbilical cord serum of her normal newborn female infant were normal. The levels of androstenedione and testosterone in serum of this woman declined slowly, but progressively, during the first two months after delivery; the serum levels of androstenedione and testosterone increased substantially, however, after she was treated with hCG eight weeks postpartum. These results are suggestive that, for reasons unknown, markedly increased androgen production with theca lutein cysts and hyperreactio luteinalis in some pregnant women results ultimately because of increased ovarian sensitivity to hCG.

Anatomic correlates of ultrasonographic prenatal diagnosis.

In utero sonographic diagnoses from forty-five malformed infants were correlated with their autopsy findings. Fifty-two malformations were diagnosed prenatally in 42 of the patients but 90 additional malformations were not. Nine sonographically diagnosed abnormalities were not confirmed at autopsy. Factors compromising sonographic diagnosis included: limited examinations, small fetal size, timing of examination, oligohydramnios, fetal position, nature of the malformation and unfamiliarity of the ultrasonographer with specific malformation syndromes. In utero ultrasonography is an invaluable tool of diagnosing congenital malformations but has limitations.

Magnetic resonance imaging in human pregnancy.

Magnetic resonance imaging is a new noninvasive diagnostic technique that involves no ionizing radiation, has no known significant adverse biologic effects, and produces high resolution cross-sectional body images. When compared with sonography and x-ray computed axial tomography, magnetic resonance imaging may have several advantages. To investigate its clinical role in obstetrics, magnetic resonance imaging was used to examine 11 women with abnormal pregnancies. Prior ultrasound examination showed abnormal appearing fetuses in five, abnormalities of the amnionic fluid volume in five, and one each with a large adnexal mass and a molar pregnancy. Examples of images obtained from these women are presented and described. Maternal anatomy was well visualized in all women studied. Based on the preliminary experience, the authors believe that magnetic resonance imaging will be a useful adjunct for diagnostic visualization of normal and abnormal maternal anatomy. Detailed fetal imaging was also possible, and it is anticipated that magnetic resonance imaging will prove useful for fetal evaluation, especially fetal intracranial anatomy and fetal anatomy in pregnancies complicated by oligohydramnios. Because fetal subcutaneous fat is prominently depicted with magnetic resonance imaging, this technology may be useful for assessment of fetal nutritional status.

Cefotaxime treatment for women with community-acquired pelvic abscesses.

Forty-one women with pelvic abscesses complicating salpingitis were treated with parenteral cefotaxime, a newer cephalosporin. Abscesses ranged in size from 4 by 4 to 13 by 15 cm, and in 10 women (24%) they were greater than or equal to 10 cm. Neisseria gonorrhoeae was recovered from the endocervix in 17 women (41%). A mean of 26.7 gm of cefotaxime was given over a mean of 6.5 days, and operation was not required during initial therapy. Only two women (5%) required the addition of another antimicrobial. Chronic pelvic pain and recurrent infection were infrequent during the 31- to 43-month follow-up period. Five women (12%) were readmitted for elective surgical therapy because of persistent or recurrent adnexal mass 1 to 33 months following study entry. Six (15%) women became pregnant and were delivered of their infants a mean of 25 months following cefotaxime therapy.

Ultrasound prediction of fetal weight in prolonged pregnancy.

In this study we applied two commonly used birth weight prediction equations to a sample of 121 women with prolonged pregnancies. Subjects had sonographic measurements of biparietal diameter and abdominal perimeter taken within 2 days of delivery at Parkland Memorial Hospital. Although the two prediction equations were obtained from a population of women in New Haven, Connecticut, who delivered over a wide range of gestational ages, when the equations were applied to the sample of prolonged pregnancies in Dallas, Texas, there was a strong correlation (0.71) between predicted and actual birth weight. Moreover, reestimation of the New Haven equations with use of the Dallas data yielded similar regression coefficients. Finally, birth weight prediction equations for black, white, and Hispanic patients in Dallas were not significantly different. These findings suggest a remarkably constant relationship between fetal head and abdominal dimensions and birth weight over different gestational ages and for different population groups.

Magnetic resonance imaging in obstetric diagnosis.

Five patients with abnormal pregnancies were examined with ultrasound (US) and magnetic resonance imaging (MR). Three had a malformed fetus, 1 had a molar pregnancy, and 1 had an ovarian mass. Both maternal and fetal structures were clearly shown, although fetal motion may have resulted in image degradation in some cases. The authors suggest that MR may be useful in obstetric diagnosis.

Prolonged pregnancy. I. Observations concerning the causes of fetal distress.

During a 2-year prospective investigation of prolonged pregnancy in 727 women, 59 (8%) were delivered by cesarean section for fetal distress. This condition was diagnosed by means of electronic fetal heart rate monitoring in 47 of the women, and the patterns were unexpectedly characteristic of umbilical cord compression rather than uteroplacental insufficiency. Blinded sonar examinations were performed in 213 women, and the incidence of cesarean section for fetal distress as now described was significantly increased in those with oligohydramnios (two or fewer 1 cm pockets of amniotic fluid). We conclude that the pathophysiology of fetal distress in prolonged pregnancy is typically oligohydramnios that leads to compromised umbilical cord perfusion, rather than uteroplacental insufficiency.

Etiologic heterogeneity of fetal hydrocephalus diagnosed by ultrasound.

Increased use of fetal ultrasound imaging by obstetricians has led to an increased rate of in utero detection of fetal malformations. Eight patients referred for level II sonography for confirmation of suspected fetal hydrocephalus were found to have affected fetuses. Examination of the resulting fetuses and infants revealed remarkable etiologic heterogeneity for the hydrocephalus. The risk for recurrence of hydrocephalus and other malformations in future offspring of these mothers varies from negligible to 25%. This experience emphasizes that there are many causes of fetal hydrocephalus and that careful diagnostic studies must be performed on any fetus or infant found to have hydrocephalus, so that accurate genetic counseling can be provided to the family.

Sinusoidal fetal heart rate pattern after intrauterine transfusion.

Two pregnancies complicated by severe Rh-isoimmunization and the development of sinusoidal fetal heart rate patterns immediately after intrauterine transfusions are presented. An intermittent sinusoidal pattern resolved, in one fetus, with sonographic evidence of delayed but complete absorption of transfused red blood cells. In contrast, the second fetus exhibited a continuous sinusoidal pattern coincident with cardiac decompensation detected by echocardiography, severe anemia, and failure to absorb transfused red blood cells. Possible pathophysiologic mechanisms for the development of sinusoidal patterns after fetal transfusions are discussed. It is concluded that a sinusoidal fetal heart rate pattern may occur after fetal transfusion and that the subsequent course of this pattern provides meaningful information about fetal condition as well as the success of intrauterine transfusion.

Early prenatal ultrasonic findings in Klippel-Trenaunay-Weber syndrome.

Routine sonography prior to genetic amniocentesis revealed the presence of a large complex mass with pulsating channels over the anterior fetal chest wall. This led to early termination of pregnancy in a fetus affected with the rare Klippel-Trenaunay-Weber Syndrome.