Faculty Bibliography

OBJECTIVE:To estimate the rate of histologic chorioamnionitis in the presence of diagnosed clinical chorioamnionitis and determine whether clinical markers of maternal and neonatal infection are associated with histologic chorioamnionitis. METHODS:We identified singleton pregnancies from 1996 in which discharge diagnoses included clinical chorioamnionitis and reviewed maternal and neonatal records for clinical evidence of chorioamnionitis and suspected or confirmed neonatal infections. Placentas were examined for acute histologic chorioamnionitis. RESULTS:One hundred thirty-nine pregnancies with the discharge diagnosis of maternal clinical chorioamnionitis were included. Eighty-six (61.9%) had the clinical diagnosis supported by histologic chorioamnionitis. Histologic chorioamnionitis was associated with an earlier gestational age at delivery (35.7+/-6.5 weeks versus 38.6+/-2.9 weeks, P = .002), lower epidural usage (72.1% versus 92.5%, P = .004), less internal monitoring (47.7% versus 75.5%, P = .001), and possible neonatal sepsis (60.5% versus 35.8%, P = .005). For 19 of 71 (26.8%) infants with possible neonatal sepsis, placentas did not show histologic chorioamnionitis. CONCLUSION/CONCLUSIONS:Clinical chorioamnionitis and possible neonatal infection were not supported by histologic evidence for infection in 38.1% and 26.8% of cases, respectively, suggesting other noninflammatory causes of signs and symptoms.

OBJECTIVE:The purpose of this study was to compare the results of a standardized self-completed domestic abuse questionnaire with those of a directed interview in the identification of domestic abuse in pregnant patients. STUDY DESIGN/METHODS:All patients with a first prenatal visit between March 1 and September 30, 1997, were assessed for self-reported domestic abuse with a standardized domestic abuse questionnaire. This was followed by a directed interview that involved verbal review of the standardized domestic abuse questionnaire. Self-reported domestic abuse was defined as any positive response to the domestic abuse questionnaire or the directed interview. The number of patients with a positive response to either the standardized questionnaire or the directed interview, or both, were recorded. The 2 techniques were compared by the McNemar chi(2) test. The group demographics and characteristics were evaluated. RESULTS:Among the 224 patients evaluated, a total of 36% (n = 80) of the patients reported domestic abuse by either method. The standardized domestic abuse questionnaire identified 85% (n = 68) compared with 59% (n = 47) by a directed interview (P =.03). The use of the standardized domestic abuse questionnaire and the directed interview in parallel identified an additional 15% (n = 12) of patients with domestic abuse. CONCLUSION/CONCLUSIONS:A standardized domestic abuse questionnaire is superior to a directed interview in identifying self-reported domestic abuse in pregnancy. Utilizing both methods in parallel further increases the number of patients identified.

OBJECTIVE:The objectives of this study were to examine (1) the diagnostic accuracy requirements (from the cost-benefit point of view) of targeted ultrasonography versus genetic amniocentesis for prenatal detection of spina bifida in women with an elevated level of maternal serum alpha-fetoprotein, (2) the ultrasonographic accuracy of previously published studies from the cost-benefit point of view, and (3) the possible economic impact for the United States of offering targeted ultrasonography instead of routine amniocentesis to this group of patients. STUDY DESIGN/METHODS:Our cost-benefit formula was based on the hypothesis that the cost of universal genetic amniocentesis in patients with an elevated concentration of maternal serum alpha-fetoprotein in the second trimester should be at least equal to the cost of universal targeted ultrasonography, with amniocentesis used only for those with abnormalities on a sonogram. The main components of the formula included the diagnostic accuracy of targeted ultrasonography (sensitivity and specificity for detecting spina bifida), the cost of the amniocentesis package, the cost of targeted ultrasonography, and the lifetime cost of spina bifida not detected by targeted ultrasonography. After appropriate manipulation of the formula, a graph was constructed to represent the balance between the sensitivity and false-positive rate of targeted ultrasonography and was used to examine the accuracy of previously published ultrasonographic studies from the cost-benefit point of view. Sensitivity analyses included a range of prevalences of spina bifida in women with elevated maternal serum alpha-fetoprotein from 1:50 to 1:200 and false-positive rates of targeted ultrasonography from 1% to 10%. RESULTS:Assuming overall prevalences of spina bifida of 1:50, 1:100, or 1:200 among women with elevated maternal serum alpha-fetoprotein, we found targeted ultrasonography to be beneficial only if the overall sensitivities for detecting fetal spina bifida were >88%, >76%, and >51%, respectively. All 17 studies published after the mid-1980s, which used the "cranial signs" for detecting spina bifida, had accuracies compatible with economic benefits (sensitivities, 92% to 100%; false-positive rates, 0% to 3%). CONCLUSION/CONCLUSIONS:The benefit of second-trimester targeted ultrasonography for fetal spina bifida depends on diagnostic accuracy (ie, sensitivity and false-positive rate). Currently achieved ultrasonographic accuracies are compatible with net benefits. Targeted ultrasonography in patients with an elevated level of second-trimester maternal serum alpha-fetoprotein in the United States has the potential for annual savings of approximately $36 million to $49 million and for avoiding 268 fetal deaths.

OBJECTIVE:To systematically review the literature and summarize the relationship between cigarette smoking and placental abruption, and to evaluate the joint influences of smoking and hypertensive disorders (chronic hypertension and preeclampsia) on the subsequent development of abruption. DATA SOURCES/METHODS:We reviewed studies identified through a MEDLINE literature search between 1966 and 1997 and through studies cited in the references of published reports. METHODS OF STUDY SELECTION/METHODS:A total of 13 observational (seven case-control and six cohort) studies were identified which included a total of 1,358,083 pregnancies. We excluded case reports on placental abruption, and restricted the literature search to studies published in English. A meta-analysis was performed by computing pooled odds ratios based on random-effects models describing the association between placental abruption, smoking, and hypertensive disorders. Potential sources of heterogeneity among these studies were explored in detail. TABULATION, INTEGRATION, AND RESULTS/RESULTS:The overall incidence of placental abruption was 0.64% (8724 of 1,358,623). Smoking was associated with a 90% increase in the risk of placental abruption (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.8, 2.0). This pattern was consistent by study design (case-control compared with cohort studies) and smoking prevalence (low compared with high prevalence, defined as less than 30% compared with 30% or more, respectively). However, the association was significantly (p < .001) stronger among the seven studies conducted outside the United States (OR 2.1, 95% CI 2.0, 2.2), compared with the six studies conducted in the United States (OR 1.6, 95% CI 1.5, 1.8). Pooled population attributable risk percentage for each stratum ranged between 15% and 25%, implying that 15-25% of placental abruption episodes are attributable to cigarette smoking. Data on the dose-response relationship between number of cigarettes smoked per day and the risk of abruption indicate that the OR increased with increasing number of cigarettes smoked. Furthermore, a meta-analysis of the joint effects of smoking and hypertension during pregnancy on the development of abruption identified two published studies, including 102,609 pregnancies. In the presence of smoking, the risk of abruption was further increased due to chronic hypertension, mild or severe preeclampsia, or chronic hypertension with superimposed preeclampsia. CONCLUSION/CONCLUSIONS:Our meta-analyses showed an increased risk for placental abruption in relation to both cigarette smoking and hypertensive disorders during pregnancy. Because cigarette smoking is a modifiable risk factor, and hypertensive disorders are potentially treatable if diagnosed early in pregnancy, patient education, smoking cessation programs, and early prenatal care may be important factors in the prevention of placental abruption.

OBJECTIVE: The object of this study was to determine whether there are any clinically significant indication-specific variations in the accuracy of second-trimester genetic ultrasonography and to provide a risk adjustment for fetal trisomy 21 according to the results of genetic ultrasonography. STUDY DESIGN: From November 1, 1992, to September 30, 1998, a second-trimester genetic sonogram was offered to all pregnant women who were at an increased risk for fetal trisomy 21 (>/=1:274) because of either advanced maternal age (>/=35 years) or abnormal serum biochemical profile or both of these. Outcome information included the results of genetic amniocentesis if performed and the results of pediatric assessment and follow-up after birth. In determining diagnostic accuracy of the genetic sonogram the presence of >/=1 abnormal ultrasonographic marker was considered an abnormal test result. RESULTS: A total of 1835 fetuses with known outcomes underwent genetic ultrasonography between 15 and 24 weeks' gestation; of these 1792 had normal results, 34 had trisomy 21, and 9 had other chromosomal abnormalities. The likelihood of fetal trisomy 21 was reduced by 80% after a normal result of genetic ultrasonography. The overall sensitivity, specificity, and positive and negative predictive values of genetic ultrasonography for the detection of trisomy 21 were 82%, 91%, 15%, and 99.6%, respectively. There were no significant indication-specific variations in the accuracy of second-trimester ultrasonography. The sensitivity for the detection of fetal trisomy 21 ranged from 80% among women with advanced maternal age to 100% among women with both an abnormal biochemical profile and advanced maternal age. CONCLUSIONS: The likelihood of fetal trisomy 21 risk was reduced 80% after a normal result of genetic ultrasonography. In addition there were no significant indication-specific variations in the detection rate of genetic ultrasonography

OBJECTIVE: To determine sonographic findings in Down syndrome fetuses in the third trimester. METHODS: Down syndrome fetuses who had third-trimester ultrasound examinations between 25 and 41 weeks' gestation were matched for gestational age with three controls each. Fetal structural anomalies, Down syndrome dysmorphology markers (abnormal facial profile, sandal gap, tongue thrusting, clinodactyly, or hypoplastic middle phalanx of the fifth finger), and abnormal long-bone biometry (femur, humerus, tibia, and fibula; femur length to biparietal diameter ratio; and femur length to abdominal circumference ratio were abstracted from the ultrasound reports. The fetal face, hands, feet, profile, and cardiac outflow tracts are routinely evaluated in our center. RESULTS: Seventeen fetuses with Down syndrome who had third-trimester ultrasound evaluations were identified. Anomalies included cardiac defects (five), tongue thrusting (three), clinodactyly (three), abnormal profile (three), sandal gap (two), and duodenal atresia (two). Of the 17 fetuses, at least one long-bone abnormality was found in 13, at least one structural or biometric anomaly was found in 15, and at least two abnormal findings existed in 11. Abnormal ultrasound findings, including structural anomalies, short bones, and Down syndrome dysmorphology markers, were more common in cases than in matched controls. CONCLUSION: At least one abnormal ultrasound finding was present in 15 of 17 fetuses, and abnormal bone measurements or ratios were discovered in 13 of 17. Abnormal long-bone biometry at third-trimester ultrasound should raise the suspicion of fetal Down syndrome

OBJECTIVE: Our objective was to determine whether there were any differences in the placental lesions of high-risk patients with versus without ultrasonographic evidence of cervical shortening between 15 and 24 weeks' gestation. STUDY DESIGN: Women who were at risk for pregnancy loss and spontaneous preterm birth were followed by serial transvaginal cervical ultrasonography with transfundal pressure between 15 and 24 weeks' gestation. Two groups of women were identified: those in whom progressive cervical shortening developed to below 2 cm, either spontaneously or induced by transfundal pressure, and those in whom it did not. A perinatal pathologist who was blinded to the pregnancy outcome retrospectively examined placental histologic slides. The histologic placental lesions were categorized as acute or chronic inflammatory lesions, decidual vascular lesions, and coagulation-related lesions. RESULTS: There were 278 women who were followed during the study. Placentas were submitted for histologic examination in 189 cases (125 singleton, 45 twin, and 19 triplet gestations). There were 72 pregnancies with and 117 pregnancies without an ultrasonographic diagnosis of cervical shortening, respectively. Overall, there were significantly more acute inflammatory lesions in patients in whom cervical shortening developed, as determined by ultrasonographic examination. However, there were significantly more decidual vascular lesions in women in whom cervical shortening did not develop. When we examined the distribution of the placental histologic lesions in the 64 cases of multiple gestations, the only significant finding was again a greater frequency of acute inflammatory lesions in patients in whom cervical shortening developed. There was no difference in the distribution of the placental histologic lesion categories among women treated with bed rest versus cervical cerclage because of the ultrasound diagnosis of cervical shortening. CONCLUSION: Acute inflammatory lesions of the placenta were more frequent in patients with second-trimester cervical shortening. These findings support that patients with cervical shortening in the second trimester are prone to acute placental inflammation

OBJECTIVE:To examine the cost-effectiveness of prenatal carrier screening for cystic fibrosis. METHODS:A cost-benefit equation was developed that was based on the hypothesis that the cost of prenatal diagnosis required to diagnose and prevent one case of cystic fibrosis should be equal to or less than the lifetime cost generated from the birth of a neonate with cystic fibrosis. The formula was adjusted because a woman's positive or negative carrier status remains unchanged, thus eliminating the need for testing in subsequent pregnancies. The formula was manipulated to identify the optimal cost per screening test, as well as the net cost savings per prenatally diagnosed case of cystic fibrosis for various racial or ethnic groups. Sensitivity analyses included some key assumptions regarding the cost per screening test ($50-150), patient screening acceptance rates (25-100%), and therapeutic abortion rates (50-100%). RESULTS:Assuming therapeutic abortion rates of 50-100%, the net savings per prenatally diagnosed case of cystic fibrosis are $58,369-$382,369 among whites. Given the previously reported patient screening acceptance rates of 50-78%, the overall annual cost savings in the United States for whites are $161-251 million. However, the screening program was not found to be cost-effective for blacks, Asians, or Hispanics. CONCLUSION/CONCLUSIONS:Under most assumptions and sensitivity analyses, a prenatal cystic fibrosis-carrier screening program appears to be cost-effective.

OBJECTIVE:To determine 1) the diagnostic accuracy requirements of first-trimester genetic sonography from the cost-benefit point of view and 2) the economic impact of first-trimester genetic sonography for the United States on the basis of the accuracy of previously published studies. METHODS:A cost-benefit equation was developed on the basis of the hypothesis that the cost of chorionic villus sampling (CVS) in pregnant women with advanced maternal age (at least 35 years old) should be at least equal to the cost of genetic sonography with CVS used only for those with abnormal ultrasound results. The components of the equation included the diagnostic accuracy of genetic ultrasound (sensitivity and specificity for detecting Down syndrome), the costs of the CVS package and genetic ultrasound, and the lifetime cost of Down syndrome cases. RESULTS:First-trimester genetic sonography was found to be beneficial if the overall sensitivity for detecting Down syndrome was greater than 70%, and even then, the cost-benefit ratio depended on the corresponding false-positive rate. The required minimum ultrasound sensitivity varied according to the maternal age-specific prevalence of Down syndrome and ranged between 40% (for women 35 years old) to 96% (for women 44 years old). Of eight published cohorts using nuchal translucency thickness for genetic sonography, five had accuracies of genetic ultrasound compatible with net benefits. CONCLUSION/CONCLUSIONS:The benefits of first-trimester genetic sonography depend on its diagnostic accuracy. First-trimester genetic sonography has the potential for annual savings of 22 million dollars in the United States.