Oral ritodrine and preterm premature rupture of membranes.

A prospective randomized study was performed to determine whether or not oral ritodrine therapy significantly prolonged the latent period in patients with prematurely ruptured membranes. Compared with a control group of similar patients, those treated had a significantly prolonged mean latent period. In addition, 47.6% of the treatment group versus 14.2% of the control group had a latent period of more than one week.

Comparison of fetal weight estimation formulas with and without head measurements.

Most published sonographic techniques for estimating fetal weight use measurements of the biparietal diameter (BPD) and abdominal circumference. In many clinical situations, however, accurate head measurements cannot be obtained. One hundred one patients were scanned within 72 hours of delivery. Using multiple stepwise regression analysis, a best-fit formula was developed using abdominal circumference and femur length, or femur length alone. The mean error was 109 g/kg fetal weight for abdominal circumference and femur length that was comparable with BPD and abdominal circumference formulas for estimated fetal weight. The mean error when femur length was used alone was 129 g/kg fetal weight. When these models were tested prospectively on 67 patients and compared with published formulas, they yielded results that were similar in accuracy. Among these additional patients, the model using one parameter (femur length) had an average error of 114 g/kg, whereas the femur length and abdominal circumference showed a mean error of 125 g/kg.

Routine ultrasound screening for antenatal detection of intrauterine growth retardation.

This prospective screening program of a large obstetric population was designed to determine the effectiveness of ultrasonic biometry to diagnose intrauterine growth retardation. The results of 3616 pregnancies were analyzed. All pregnancies were dated before the 24th week by ultrasonic measurements. The study compared the effectiveness of three ultrasonic growth parameters: biparietal diameter (BPD), head circumference, and abdominal circumference, to detect intrauterine growth retardation and to determine the optimal gestational age to perform the scan for this purpose. To maintain a high sensitivity required in a screening program, all ultrasonic measurements below the 25th percentile for gestational age were considered abnormal. The predictive value of a positive test in this situation ranged from 0.25 to 0.55, depending on the week of gestation in which the scan was performed. Accuracy of predictions improved greatly when the scans were performed within two weeks of delivery. Abdominal circumference measurements were more predictive of intrauterine growth retardation than either head circumference or BPD measurements or the combination of these parameters. In view of the sensitivity of the test and the prevalence of the disorder, it is concluded that 34 +/- 1 weeks of gestation is the optimal time to screen patients ultrasonically for intrauterine growth retardation.

Routine ultrasound screening for the prediction of gestational age.

In a technician-oriented routine ultrasound program, the value of screening an entire obstetric population for predicting gestational age based on a single measurement was evaluated over selective scans performed on the basis of uncertain menstrual history. Consecutive pregnancies of 4527 women were scanned, and the results were analyzed. Gestational ages were determined by both menstrual history and ultrasonic crown-rump length or biparietal diameter (BPD) measurements. The estimated date of confinement based on ultrasound measurements was compared with menstrual history in its ability to predict the actual onset of spontaneous labor. Of patients with optimal menstrual history, 84.7% delivered within +/- two weeks of the date predicted. Only 69.7% delivered within +/- two weeks of the estimate date of confinement based on suspect menstrual history. Crown-rump length measurements were as predictive (84.6%) as optimal menstrual history. Biparietal diameter measurements done between 12 and 18 weeks' gestation were significantly more accurate in gestational predictions (89.4%) than those based on menstrual history (P less than .001). It is concluded that ultrasound cephalometry before 18 weeks is the single best dating parameter.

Antenatal classification of hydrops fetalis.

Among 12,572 pregnant women referred for ultrasound examination from 1985-1990, 76 fetuses had ultrasonographic findings of hydrops fetalis, ten immune and 66 nonimmune. Fetuses with cystic hygroma (20), heart defects or arrhythmias (13), or other congenital anomalies (15) accounted for the majority of the nonimmune cases. Antenatal chromosomal studies were available in 42 fetuses with nonimmune hydrops, of which 14 (34%) were abnormal with seven monosomes and six trisomies. Seventeen cases of hydrops (22%) were classified as idiopathic because they had no recognizable etiology. It is concluded that: 1) The ultrasonographic incidence of fetal hydrops in referral centers can be as high as one in 165 pregnancies; 2) most cases of fetal hydrops are of the nonimmune type, which can occur in a low-risk population and can be detected with early second-trimester ultrasound screening; and 3) the complexity of this condition and the high rate of chromosomal abnormalities require referral to a high-risk center for evaluation and pregnancy management.

Prenatal diagnosis of congenital adrenal hyperplasia.

In patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, the concentrations of the cortisol precursor 17-alpha hydroxyprogesterone (17-OHP) and its metabolite delta 4-androstenedione (delta 4 A) are increased. CAH was diagnosed in twins by measurement of 17-OHP and delta 4 A concentrations in amniotic fluid obtained by amniocentesis from both amniotic cavities at 17 weeks' gestation. Both prenatal karyotypes were 46,XX. Spontaneous labor and delivery of 2 nonviable fetuses with genital masculinization occurred at 26 weeks' gestation. It is concluded that delta 4 A measurement, like 17-OHP quantitation, is valuable in the prenatal diagnosis of CAH; that both methods appear useful in prediction of CAH in twin fetuses; and that abnormal adrenal-mediated masculinization in female CAH is well established before the end of the second trimester.

Fetal sacrococcygeal teratoma.

Sacrococcygeal teratoma (SCT) is being diagnosed before birth with increasing frequency. We were recently consulted about management of a 22-week fetus with SCT and reviewed our experience (6 cases) and the literature. We found that most fetal SCT present from 22 to 34 weeks gestation with a uterus enlarged by the tumor and/or associated polyhydramnios; although the American Academy of Pediatrics Surgical Section clinical classification is an important prognostic indicator in neonatal SCT, it does not appear to predict outcome in fetal SCT; associated chromosomal abnormalities or life threatening anomalies are rare; presentation after 30-weeks gestation is a relatively good prognostic sign with fetal survival, after planned cesarean delivery, in 6 of 8 cases; and hydrops and/or placentomegaly in association with fetal SCT predicts fetal demise soon after diagnosis with 7 of 7 cases dying in utero.

Death due to high-output cardiac failure in fetal sacrococcygeal teratoma.

Fetal sacrococcygeal teratoma (SCT) is being recognized with increasing frequency. Placentomegaly and hydrops fetalis are preterminal events, and it has been suggested that fetal death may be due to high-output cardiac failure from arteriovenous shunting through the tumor. We had a chance to examine this hypothesis when a 21-week fetus presented with a huge sacrococcygeal teratoma. There were marked placentomegaly, cardiomegaly, hyperdynamic ventricles, and a pericardial effusion. Doppler studies showed tremendous flow through the SCT with extreme enlargement of the inferior vena cava, consistent with congestive heart failure from increased flow through the tumor. Hydrops developed, and the fetus was delivered because of placental abruption. This case provides supportive evidence that the teratoma acts as a large arteriovenous shunt, causing high-output cardiac failure. We have now collected 18 more cases of sacrococcygeal teratoma diagnosed in utero. Of the total 45 cases of fetal SCT, 9 had placentomegaly and/or fetal hydrops and all 9 fetuses died in utero or shortly after birth. We conclude that the only hope for survival in these severely affected fetuses is to reduce blood flow to the tumor before birth.

Ultrasonographic growth and Doppler hemodynamic evaluation of fetuses of obese women.

All fetuses benefit from ultrasonographic estimation of gestational age and evaluation of growth patterns. Monitoring the pregnancies of obese women is perceived as more difficult than monitoring those of nonobese women. The aim of this study was to determine if maternal obesity affects the growth and Doppler resistance indices (RI) of the fetus. Twenty-eight women with a preconception weight > 90.7 kg underwent obstetric ultrasonographic evaluations from the 20th week of gestation. Their ultrasonographic data were compared with those of controls. Ten of the obese women developed gestational diabetes and had lower umbilical artery RIs for a given gestational age (P < .0001) than did those obese women without other medical complications, those with medically controlled pregnancy-induced hypertension or those from the control population. The relation between fetal unit weight and umbilical artery RIs was established. The pattern of RI changes was similar in all groups when estimated fetal weight instead of gestational age was used as the covariant. Fetal growth and Doppler velocimetry can be monitored adequately in obese women. Gestational diabetes significantly influences the pattern of fetal growth and the impedance to flow in the umbilical artery.

Twin pregnancy. Ultrasonographically observed changes in fetal presentation.

The changes in fetal presentation throughout pregnancy were observed ultrasonographically in 332 sets of twins. Seventy-eight percent of the leading twins were vertex at 26-30 weeks' gestational age, 75% at 31-34 weeks and 81% at 35-38 weeks. The incidence of nonvertex presentation for either twin was 73.0%, 64.5% and 59.5% at the same gestational ages. The results are not significantly different from those on concordant twins delivered at the same gestations. Thus, one can counsel parents of twins at all gestational ages in regard to the potential for malpresentation.

Endocervical curettage as a routine part of colposcopic examinations for abnormal cervical cytology.

Two hundred seven consecutive patients with adequate colposcopy and routine endocervical curettage (ECC) were evaluated for abnormal cervical cytology. A positive ECC was found in 31 patients (15.0%). In patients with grade III cervical intraepithelial neoplasia (CIN), ECC was positive 260% more often than in patients with CIN 1 and 2 (P less than .005). The ECC was the only evidence of dysplasia in three instances. The data suggest that routine ECC should be an integral part of the colposcopic examination of patients with abnormal cytology.

Medical and surgical treatment of inflammatory bowel disease in pregnancy.

Inflammatory bowel disease is a relatively common spectrum of disorders of the gastrointestinal tract in women of the reproductive age group. Although Crohn's disease may decrease fertility, female reproductive ability is normal in UC. In general, IBD is not a contraindication to pregnancy or vaginal delivery and is not an indication for therapeutic abortion. Pregnancy will have a variable effect on IBD, and the patient's experience in previous pregnancies is not prognostic of future pregnancies. Whenever possible, pregnancies should be planned when IBD is quiescent and the patient is on a minimal drug regimen. The treatment of IBD is essentially the same regardless of pregnancy. Aggressive medical management with supportive therapy, corticosteroids, and sulfasalazine is effective in the treatment for this disorder. Sulfasalazine is effective in preventing recurrence of UC. Surgical treatment may be necessary in pregnancy. An enlarged uterus may make recognition of acute complications difficult, and fear of radiation may decrease the number of diagnostic x-ray studies performed. A proctocolectomy and ileostomy is curative for UC, but no procedure will cure Crohn's disease. In pregnancy, a limited surgical procedure may be necessary. There is a high incidence of fetal loss if surgery is required in IBD. This fetal loss is probably caused by the fulminant nature of the disease rather than surgery itself. If surgery is indicated, however, it should be performed for maternal indications despite the risk to the fetus. As can be seen, management of IBD in pregnancy is not to be taken lightly and requires extensive collaboration between obstetrician, gastroenterologist, surgeon, and other support personnel.

Transvaginal color Doppler imaging in the assessment of uteroplacental blood flow in the normal first-trimester pregnancy.

Characteristic changes of low resistance and high diastolic blood flow velocity were identified by Doppler studies starting in the early phase of the second trimester. These changes were attributed by some authors to trophoblastic invasion of the uterine vasculature converting the uterus into a low-resistance organ. Because of technical limitations previous studies were confined to the uterine artery and its main branches. With the development of color Doppler and transvaginal ultrasonography we can now identify blood flow in various small vessels in the placental bed. This study was performed to assess the ability of color Doppler ultrasonography to evaluate subtrophoblastic blood flow by color identification in the early phase of normal pregnancy from 5 to 9 weeks' gestation. Results show that the characteristic increase in diastolic blood flow is evident as early as 5 weeks' gestation.

Ultrasound diagnosis of intrauterine growth retardation.

Intrauterine growth retardation is associated with increased perinatal morbidity and mortality. Assuming an accurately dated pregnancy, ultrasonic estimations of fetal weight can be used to predict intrauterine growth retardation. Antenatal detection of this condition will have an impact on management and ideally may improve outcome.

Combined intravascular-intraperitoneal transfusions in hydropic twins due to Rh (D) alloimmunization.

Fetal hydrops due to Rh (D) alloimmunization can be reversed by ultrasound-guided intravascular transfusions with improvement in perinatal morbidity and mortality. We report a case of in utero intravascular transfusion in hydropic twins which reversed all the hydropic findings within 3 days. A simple intraperitoneal transfusion was performed in each twin 2 weeks later, and only one neonatal exchange transfusion was required for the ultimate survival of both twins.

Color Doppler imaging in the assessment of uteroplacental blood flow in abnormal first trimester intrauterine pregnancies. An attempt to define etiologic mechanisms.

The addition of color Doppler imaging (CDI) to the vaginal probe now enables sonographers to study more accurately the maternal-fetal circulation at the early stages of the gestation. Doppler studies of normal intrauterine first trimester gestations have been published, and our investigation was an attempt to study uteroplacental blood flow in abnormal intrauterine first trimester gestations. Although the calculated indices did not differ significantly from those found in normal gestations, we did find a higher rate of color detection in gestations defined as anembryonic as compared to those defined as missed abortions. Circulation abnormalities probably play a significant role in early pregnancy failures, and we believe CDI will help define the different etiologic mechanisms causing these early complications.

Ultrasonic prediction of discordant growth in twin pregnancies.

In this prospective study conducted from 1984 through 1987, the ability to correctly predict growth discordancy in twin gestations by ultrasonic estimated fetal weights is examined. Discordancy was defined as an intertwin birth weight difference of 25% or greater. This method resulted in a sensitivity rate of 77% and a specificity rate of 92%. The positive predictive value of an abnormal test (i.e. discordant growth) was 67% and the negative predictive value of a normal test (i.e. concordant growth) was 95%. The perinatal mortality rate of 217/1,000 in discordant twin fetuses was significantly higher than 29/1,000 in the concordant twins in this study population (p < 0.01) and even more of a contrast to the rate of 10/1,000 in our singleton population. Accurate prediction of discordant twin pregnancies which are at high risk for poor outcome opens the opportunity for potential in utero treatment modalities.

Sonographic measurement of the fetal iliac bone: growth and relation to femur length in assessment of gestational age.

Diagnostic ultrasonography has given us the opportunity to diagnose several congenital malformations in utero. Skeletal dysplasias is a heterogeneous group of disorders of the skeleton. Although disorders of bone growth are often diagnosed in utero, it is usually a general diagnosis because the exact syndrome cannot be specified. This is due to the fact that many anomalies of the skeleton have similar features. The wing of the iliac bone can be either affected or normal in skeletal dysplasias and its appearance may help in the differential diagnosis. This study was undertaken to establish values for the width of the iliac bone wing during normal gestations and thus enable us to use it in the evaluation of fetal growth and the recognition of specific congenital anomalies.

The present place of routine ultrasound screening.

The value of routine ultrasound examinations is illustrated in Table 3. Ultrasound examination may of course be indicated in early pregnancy on clinical grounds. If it is not, we recommend that all patients should have measurement of the BPD between 16 to 18 weeks' gestation even if they have optimal menstrual histories. It is preferable to have a routine ultrasound service if a MSAFP programme is offered because, although it is possible to scan only patients with a raised MSAFP, prior knowledge of gestational age helps in the timing of the sample and prevents concern in patients with inaccurate dates. At 16 to 18 weeks' gestation multiple pregnancies can be diagnosed reliably and many structural abnormalities can be detected even when the routine examination is performed by non-medically trained personnel. A fundal placenta at 16 to 18 weeks' gestation excludes the possibility of placenta praevia. Seeing the fetus on the ultrasound screen and watching fetal movements strengthens parental feelings towards pregnancy. A repeat ultrasound examination in the third trimester to measure AC is superior to clinical means of detecting growth retardation. Placental localization at this gestation is accurate and has removed the need for the hazardous 'examination under anaesthetic'. If facilities are available we recommend that every patient has a repeat scan in the third trimester. If facilities are insufficient then we recommend that high risk patients have serial scans and that other patients have SFH measurement at each antenatal visit, and that only those that have a low SFH should have repeat ultrasound examinations. Until the day arrives when there is sufficiently trained personnel, adequate equipment and time to perform detailed examinations of all fetuses at 16 to 18 weeks' gestation, together with serial examination and measurement of all growth parameters, we feel the above schema makes the best use of available facilities.

Ultrasonographic measurement of fetal femur length in growth disturbances.

Ultrasonographic measurement of fetal femur length is a recognized technique for determination of gestational age and fetal growth. A total of 280 pregnant women were studied, each of whom had pathologies with the potential to either accelerate or delay fetal growth. There were 1000 measurements of the fetal femur length performed on these 280 fetuses. A total of 125 fetuses were found to have a growth disturbance-91 with asymmetrical intrauterine growth retardation and 34 with macrosomia. Comparison of fetuses with either intrauterine growth retardation or macrosomia with appropriate-for-gestational-age fetuses showed that the femur length is not statistically affected by intrauterine growth abnormalities.