Nicola Strobelt

A prospective study of the role of ultrasound in the management of adnexal masses in pregnancy

Objective To assess the clinical relevance of adnexal masses in pregnancy and the usefulness of ultrasound in their management.

Screening for congenital heart disease with the four-chamber view of the fetal heart

OBJECTIVE Our objective was to determine the efficacy of the four-chamber view of the fetal heart in routine ultrasonographic examination as a screening tool for congenital heart defects. STUDY DESIGN A prospective cohort study compared the detection rate of congenital heart defects among 5336 pregnant women screened with the ultrasonographic four-chamber view of the fetal heart from 1987 through 1989 with that among 3680 patients examined ultrasonographically without the four-chamber view during the 2 preceding years (1985 through 1986). All patients were followed until delivery or termination of pregnancy, and clinical or autopsy confirmation of prenatal findings were obtained on all cases. RESULTS The overall incidence of congenital heart diseases was 5.2 per 1000 (47/9016). During the years 1985 through 1986 15 neonates with congenital heart diseases were identified, seven of which were prenatally diagnosed (sensitivity 43%). During the period 1987 through 1989 a four-chamber view of the fetal heart was obtained in 95% of cases; 32 cases of congenital heart disease occurred, 26 of which were diagnosed antenatally (sensitivity 81%; p = 0.01). Two false-positive diagnoses were made during the second time period, giving a specificity of 99.9%. CONCLUSION The four-chamber view of the fetal heart is easily obtained, does not significantly increase the duration of a routine ultrasonographic examination, and has an excellent sensitivity for the identification of congenital heart diseases.

Prognostic indicators in the prenatal diagnosis of agenesis of corpus callosum

OBJECTIVE Our aim was to determine the accuracy of ultrasonography in the prenatal diagnosis of agenesis of the corpus callosum and to establish whether ultrasonography can provide prognostic indicators in cases of agenesis of the corpus callosum. STUDY DESIGN Prospective ultrasonographic study of the corpus callosum in all cases during an 8-year period in which fetal cerebral ventriculomegaly was detected. RESULTS A total of 14 cases of agenesis of the corpus callosum are reported. In seven cases agencies of the corpus callosum was an isolated finding, and in seven cases it was associated with other abnormalities. Six cases involved mendelian syndromes (3 Lissencephaly syndrome, 2 Aicardi syndrome, and 1 Andermann syndrome), and one case was associated with trisomy 13. In 5 of 14 fetuses, all male, agenesis of the corpus callosum was an isolated benign finding. The corpus callosum could never be visualized before midgestation, but diagnosis of agenesis of the corpus callosum was very accurate after 20 weeks. CONCLUSION Prenatal ultrasonographic findings suggestive of agenesis of the corpus callosum should be followed by a careful search for associated anomalies that may indicate genetic syndromes. Isolated agenesis of the corpus callosum is often an isolated, benign finding, particularly in male fetuses. In families at risk for mendelian syndromes associated with agenesis of the corpus callosum, lack of visualization of this structure is suggestive of the diagnosis.

Cervico‐isthmic pregnancy: a case report, critical reappraisal of the diagnostic criteria, and reassessment of the outcome

During the first trimester of pregnancy, the cervix is limited cranially by the internal os, which can be defined in two ways: histologically or anatomically. Histologically, the internal os is the transition point from the endocervical mucosa to the isthmic mucosa that resembles the corporal mucosa although thinner and richer of supporting tissue. The anatomical internal os, which is the zone of transition between isthmus and uterine corpus, is located 5 to 16 mm cranially to the histological os. Therefore, during the first trimester, ultrasonography cannot distinguish the transition between isthmus and cervical canal, but only between isthmus and uterine corpus (1). From the 12th week onward, the isthmus progressively unfolds into the uterine cavity, becomes occupied by the gestational sac, and takes the name of lower uterine segment (2). Normally, the gestational sac implants on the uterine corporal decidua, and only during the second trimester does it occupy the space of the widened isthmic canal. Cervico-isthmic pregnancy is a rare complication of sac implantation, which is poorly characterized both diagnostically and in its development. We have prospectively followed a cervico-isthmic pregnancy with serial ultrasonographic examinations and, upon reviewing similar cases reported in the literature, we provide new insights on the diagnostic criteria and natural history of this uncommon clinical entity.

Critical reappraisal of the utility of sonographic fetal femur length in the prediction of trisomy 21

Measurement of femur length (FL) has been advocated as part of a genetic sonogram for the prediction of Down syndrome (DS). However its predictive ability has been inconsistent. We have studied the diagnostic value of this sonographic parameter in a prospective cohort of women with singleton gestations undergoing genetic sonogram between 14 and 22 weeks because of advanced maternal age or family history of aneuploidies. Genetic sonograms were performed at a mean gestational age of 17.0 weeks (range 14–22). DS was diagnosed in 30 fetuses, while 888 were euploid. Mean±SD observed/expected (O/E) values of FL (1.00±0.10 versus 0.97±0.01, p=0.07) were not significantly different between euploid and DS fetuses. Comparison of the regression equations of FL versus biparietal diameter revealed that while the intercepts were not significantly different between euploid and DS fetuses, the difference in slopes reached significance (p=0.04) suggesting that the predictive ability of FL may increase with advancing gestational age. In addition, a MEDLINE search (National Library of Medicine) was conducted for articles published between 1985 and 1998 on fetal femur length in the prediction of trisomy 21. Review of the published literature on the subject suggests that FL is not a consistent or reliable sonographic predictor of DS. Published thresholds of FL should not be used outside of the Institution from which they originated, and each Institution should establish whether this parameter has predictive ability in its own population. Copyright

Transabdominal amnioinfusion in oligohydramnios at term before induction of labor with intact membranes: A randomized clinical trial

OBJECTIVE Our purpose was to determine the effectiveness of transabdominal amnioinfusion before induction of labor in reducing the incidence of fetal distress in pregnancies with oligohydramnios at term. STUDY DESIGN Between June 1991 and September 1994 primiparous women with ultrasonographic evidence of oligohydramnios at term, intact membranes, and unripe cervix (Bishop score < or = 6), candidates for induction of labor with cervical or vaginal prostaglandin E2 gel, were randomly selected to receive transabdominal amnioinfusion (amnioinfused group, n = 39) or to proceed with direct labor induction (control group, n = 40). Inclusion criteria were (1) singleton gestation, (2) vertex presentation, (3) ultrasonographic estimation of fetal weight > or = 2500 gm, and (4) reactive nonstress test. Fetoneonatal outcome variables were compared between the two groups. Statistical analysis used contingency tables, Student t test, or Wilcoxon rank-sum tests, where applicable. RESULTS Amnioinfusion was successfully performed in 100% of the patients randomized for the procedure. The incidence of severely abnormal fetal heart rate tracings was significantly higher in the control than in the amnioinfused group (42% [17/33] vs 5% [2/37], relative risk 12.9, 95% confidence interval 2.4 to 56.4). The rate of cesarean sections performed for fetal distress was fivefold higher in the control group (25% [10/40] vs 5% [2/39], relative risk 4.9, 95% confidence interval 1.1 to 32.4). No bleeding complications or fetomaternal infectious morbidity were noticed. CONCLUSION Transabdominal amnioinfusion is a safe, effective option for the prevention of fetal distress in pregnancies with oligohydramnios at term with intact membranes and unripe cervix.

Head-to-body delivery interval using 'two-step' approach in vaginal deliveries: effect on umbilical artery pH.

Objective. To assess the duration of head-to-body interval using a ‘two-step’ approach to delivery that include waiting for the next contraction to deliver the shoulders; and its effect on umbilical artery pH and neonatal outcome. Study design. Prospective observational study on vaginal deliveries with singleton cephalic fetuses at term from June to December 2005. Clinical variables were evaluated in reference to umbilical artery pH and evidence of neonatal acidemia, defined as pH ≤ 7.10 or base excess (BE) ≤ −12 in a multivariate model. Results. Head-to-body interval was timed and recorded in 789 deliveries. The mean head-to-body interval was 88 ± 61 s. Although head-to-body interval was significantly correlated to umbilical artery pH (p = 0.02), the decline in umbilical artery pH in relation to the head-to-body interval was clinically not significant (0.0078 units for every additional minute of the interval). At the multivariate analysis, umbilical artery pH ≤ 7.10 and/or BE ≤ −12 were significantly related to abnormal fetal heart rate tracing during the second stage (p = 0.012) and operative vaginal delivery (p = 0.045), but not to head-to-body interval (p = 0.25). Shoulder dystocia occurred in three cases (0.38%). Conclusion. A ‘two-step’ approach to birth does not significantly increase the risk of neonatal acidemia.

Randomized study on removable PGE2 vaginal insert versus PGE2 cervical gel for cervical priming and labor induction in low-Bishop-score pregnancy

Background. Dinoprostone vaginal insert has been compared to Dinoprostone cervical gel in few studies, whose cases presented different Bishop scores and gestational ages at admission, and various treatment strategies in control arms. The present study compares the vaginal insert to the cervical gel in patients with low Bishop score at term. Methods. Prospective multicenter randomized trial, with parity‐based randomization. Admission criteria: single pregnancy with Bishop score of 0–4, gestational age of 37–41 weeks, intact membranes, no previous cesarean section, no bleeding or abnormal cardiotocography at admission. Results. Vaginal prostaglandins were required as a second‐line induction procedure in 25% of study patients versus 47.1% of controls (p<0.03, κ2). Study patients experienced shorter induction‐to‐delivery time (920±428 versus 1,266±740 min, p<0,01), with a mean difference of 5 h and 46 min between the groups. Even though patients that received vaginal insert showed a trend of increased incidence of abnormal cardiotocography during labor (12% versus 6.3%) and hyperkinetic labor (11.8% versus 2.1%), the incidence of cesarean sections (21.4% versus 21.6%), cesareans for fetal distress (12.5% versus 11.8%), and umbilical artery pH < 7.10 (4.9% versus 2.5%) was comparable between the two groups. Conclusions. Dinoprostone vaginal insert is more efficient than cervical gel in promoting cervical priming and labor induction in low‐Bishop‐score patients at term. The vaginal insert placement seems to be safe for the mother and the newborn, although larger studies are required to investigate uterine hyperstimulation incidence.

Caveats for the Use of Humerus Length in the Prediction of Fetal Down Syndrome

Objective: To assess the reliability and reproducibility of fetal humerus length in the diagnosis of trisomy 21. Methods: Cohort study inclusive of 22 trisomy 21 fetuses, who underwent ultrasonographic examination between 14 and 22 weeks’ gestation, and 457 euploid controls. Regression analysis was performed for humerus length as function of biparietal diameter. Based on the generated regression equation in euploid fetuses, expected values of humerus length for a given biparietal diameter were calculated. The ratios of observed to expected (O/E) humerus length values were compared between euploid and trisomy 21 fetuses using Student’s t test. Receiver operating characteristic (ROC) curve analysis was used to detect optimal thresholds of O/E humerus length for diagnosis of trisomy 21. In addition, a MEDLINE search was conducted for articles published on humerus length as predictor of trisomy 21. Results: No differences were present between the regression lines of trisomy 21 and euploid fetuses (mean ± standard deviation O/E humerus length in euploid and aneuploid fetuses: 1.00 ± 0.10 vs. 0.97 ± 0.11, p = 0.21). The optimal threshold O/E humerus length <0.88 identified by ROC curve analysis had a sensitivity of 18% and a false-positive rate of 9% for the diagnosis of trisomy 21. From a review of the evidence provided by the 17 published series on humerus length as predictor of Down syndrome, the following caveats emerge: (1) with a median false-positive rate of 5% (range 1–12%), the median sensitivity of humerus length was only 28% (range 15–64%); (2) differences were present among centers in the regression lines of euploid fetuses and in the optimal diagnostic thresholds of humerus length, suggesting inter-center variability, and (3) most populations studied were at high genetic risk for trisomy 21, hence the diagnostic ability of humerus length in low risk populations has not been tested. Conclusions: The ability of humerus length to predict trisomy 21 is inconsistent. Only institutions with locally generated regression equations and documented predictive ability of this marker should utilize humerus length as a screening test for trisomy 21, alone or incorporated into diagnostic algorithms with serum or other sonographic markers of trisomy 21. The diagnostic ability of humerus length in low risk populations is currently unknown.

A Prospective Study of the Role of Ultrasound in the Management of Adnexal Masses in Pregnancy

OBJECTIVE To assess the clinical relevance of adnexal masses in pregnancy and the usefulness of ultrasound in their management. DESIGN A prospective study on pregnancy complicated by adnexal masses. SETTING Department of Obstetrics and Gynaecology in Italy. POPULATION 6636 women with pregnancy in utero followed in our clinic from January 1996 to December 1999. METHODS From 1996 to 1999, all ovarian cysts with a diameter exceeding 3 cm were prospectively recorded and followed. The management was expectant except in case of symptoms or suspected malignant features. Cysts suggestive of borderline tumours were treated expectantly. MAIN OUTCOME MEASURES Clinical relevance of adnexal masses in pregnancy, the outcome of these pregnancies and the usefulness of ultrasound examination in their management. RESULTS We detected 82 cysts in 79 of 6636 women (1.2 in 100 term pregnancies). Sixty-eight women were asymptomatic at the time of diagnosis, whereas 11 (13.9%) were diagnosed because of pain. Diagnosis occurred in the first trimester for 57 cases and in the second or third trimester in 22 (27.8%). One-half of the cysts were simple and anechoic at ultrasound. Fifty-seven had a diameter not exceeding 5 cm. Forty-two cyst resolved in pregnancy without treatment. Three cysts required surgery within few days (torsion). One woman required laparotomy at the 37th week of gestation, due to torsion. When one case of termination was excluded, 78 women delivered at term (66 vaginally, 12 by caesarean section). Nineteen women underwent surgery after pregnancy. We recorded three Stage Ia borderline tumours, accounting for 3/82 cysts (3.6%) and 3/30 persisting masses (10%). CONCLUSION Ultrasound allows definition of ovarian cysts in pregnancy and this positively impacts on management. The incidence of cancer among persistent masses is lower than previously reported. Acute complications in stable cysts are extremely uncommon after the first trimester. An expectant management is successful in the majority of cases and should be considered more often. Routine removal of persistent cysts is not justified.