Harold E. Fox

Intrapartum electronic fetal heart rate monitoring and the prevention of perinatal brain injury

OBJECTIVE: Electronic fetal heart rate monitoring (EFM) is the most widely used method of intrapartum surveillance, and our objective is to review its ability to prevent perinatal brain injury and death. DATA SOURCES: Studies that quantified intrapartum EFM and its relation to specific neurologic outcomes (seizures, periventricular leukomalacia, cerebral palsy, death) were eligible for inclusion. MEDLINE was searched from 1966 to 2006 for studies that examined the relationship between intrapartum EFM and perinatal brain injury using these MeSH and text words: “cardiotocography,” “electronic fetal monitoring,” “intrapartum fetal heart rate monitoring,” “intrapartum fetal monitoring,” and “fetal heart rate monitoring.” METHODS OF STUDY SELECTION: This search strategy identified 1,628 articles, and 41 were selected for further review. Articles were excluded for the following reasons: in case reports, letters, commentaries, and review articles, intrapartum EFM was not quantified, or specific perinatal neurologic morbidity was not measured. Three observational studies and a 2001 meta-analysis of 13 randomized controlled trials were selected for determination of the effect of intrapartum EFM on perinatal brain injury. TABULATION, INTEGRATION, AND RESULTS: Electronic fetal monitoring was introduced into widespread clinical practice in the late 1960s based on retrospective studies comparing its use to historical controls where auscultation was performed in a nonstandardized manner. Case-control studies have shown correlation of EFM abnormalities with umbilical artery base excess, but EFM was not able to identify cerebral white matter injury or cerebral palsy. Of 13 randomized controlled trials, one showed a significant decrease in perinatal mortality with EFM compared with auscultation. Meta-analysis of the randomized controlled trials comparing EFM with auscultation have found an increased incidence of cesarean delivery and decreased neonatal seizures but no effect on the incidence of cerebral palsy or perinatal death. CONCLUSION: Although intrapartum EFM abnormalities correlate with umbilical cord base excess and its use is associated with decreased neonatal seizures, it has no effect on perinatal mortality or pediatric neurologic morbidity.

Transvaginal ultrasonographic evaluation of the cervix before labor: Presence of cervical wedging is associated with shorter duration of induced labor

OBJECTIVE Our purpose was to test the hypothesis that transvaginal ultrasonographically determined characteristics of the cervix are associated with duration of induced labor. STUDY DESIGN Fifty-three patients scheduled for induction of labor underwent transvaginal ultrasonography and digital cervical examinations before labor induction. Cox proportional-hazards multiple regression analysis was performed to determine the variables that made a significant contribution to the prediction of latent-phase and total labor duration. In the analysis the possible confounding effects of exogenous prostaglandin, previous vaginal delivery, and previous termination of pregnancy were controlled. RESULTS Latent-phase and total labor duration were significantly associated with the presence of cervical wedging noted on transvaginal ultrasonography and administration of prostaglandin but not with the result of digital examination of cervical effacement or dilatation. Latent-phase duration was also associated with cervical length measured by transvaginal ultrasonography. The presence of wedging was significantly associated with shorter latent (15.9 +/- 1.7 vs 34.1 +/- 3.8 hours, p = 0.0001) and total (22.0 +/- 1.8 vs 38.3 +/- 3.6 hours, p = 0.0001) labor length. CONCLUSION The presence of wedging and decreased cervical length observed by transvaginal ultrasonography is associated with a shorter duration of induced labor and may be useful in the evaluation of induction candidates.

Vaginal ultrasound for diagnosis of placenta previa.

Transvaginal sonography was compared with transabdominal sonography in 35 women with suspected placenta previa. The transvaginal sonographic technique did not result in vaginal bleeding in any of the patients. The internal os and its relationship to the location of the placenta were visualized by transvaginal sonography in all patients, but only in 24 patients (69%) by transabdominal sonography. Transvaginal sonography ruled out placenta previa in 13 cases thought to be placenta previa by abdominal sonography. The transvaginal diagnosis in these 13 patients was confirmed at delivery. Thirty-four of the 35 women have been delivered. The diagnosis at delivery confirmed the transvaginal sonographic diagnosis in 29/34 cases and the transabdominal diagnosis in 16/34. Transvaginal sonography did not predict the delivery diagnosis in five patients who were erroneously believed to have placenta previa by both sonographic techniques.

Coordinated interpersonal timing in adult-infant vocal interactions: A cross-site replication**

Coordinated interpersonal tinning exists when the temporal pattern of each partner in a dialogue is predictable from that of the other. Using a completely automated microanalytic technique to time the sequence of vocal sounds and silences in an interaction, we studied 28 four-month-old infants in face-to-face play with mother and a female stranger. Fifteen infants were recorded on one site and 13 at another. Time-series regression was used to evaluate the direction and magnitude of interpersonal prediction. Results indicated that (a) significant coordination (or its absence) occurred at both sites for 90% of the comparisons, and (b) the lag that best predicted the partner was 20 to 30 s at both sites. Unlike the labor-intensive microanalytic coding techniques that have dominated mother-infant interaction research, this work has the following advantages: (a) the automated instrumentation times behavior with a precision unobtainable by the unaided human observer; (b) the sound-silence variables are unambiguously defined for computer processing; and (c) the microanalytic method is applicable to large-sample studies. This automated method has shown its clinical utility in its power to predict 1-year developmental outcomes from 4-month coordinated interpersonal timing.

Overview of progress in patient safety

In the 11 years since the Institute of Medicine reported ubiquitous problems with the quality and safety of patient care in the United States, efforts been made to improve health care. Obstetrics and gynecology has made some improvements; however, similar to other areas of health care, progress has been slow. The major deterrents are complexities in our health care system and culture and an immature science of safety and quality that makes measurement and evaluation of progress difficult. This article describes the efforts that have been made in obstetrics and gynecology to identify causes or factors that contribute to adverse outcomes, to develop measures of quality and safety, and to make improvements. It also offers a framework to help organize patient safety research and improvement. Finally, this article offers ways the American Congress of Obstetricians and Gynecologists can organize and support future work.

False-negative syphilis screening: The prozone phenomenon, nonimmune hydrops, and diagnosis of syphilis during pregnancy

The prevalence of congenital syphilis is rapidly rising in several areas of the United States. Efforts to control the disease depend on the effectiveness of established screening strategies and treatment of infected pregnant women. False-negative test results hinder these efforts and leave the fetus at risk for acquiring congenital syphilis. Recently we encountered four cases of false-negative syphilis serologic results in women who gave birth to infants with congenital syphilis. The false-negative results were caused by the prozone phenomenon. The prozone phenomenon, seen during primary and secondary syphilis, occurs because a higher than optimal amount of antibody in the tested sera prevents the flocculation reaction typifying a positive result in reagin tests. Serum dilution is necessary to make the correct diagnosis. We recommend that for any pregnant woman with apparently negative syphilis serologic results in whom fetal compromise of unknown etiology exists, particularly nonimmune hydrops, nontreponemal testing should be repeated using serum dilutions to prevent a missed diagnosis of syphilis. We further recommend serum dilution as a routine procedure for all pregnant women in areas of high syphilis prevalence.

Fetal evaluation by real-time imaging.

The application of real-time imaging to the study of fetal morphology and function is an exciting advance. Rapid accurate study of fetal dynamics is possible with this apparently safe, noninvasive technique. Animal studies have revealed the general physiology of fetal breathing movements, which are now under extensive investigation with real-time imaging in the human. There is evidence for circadian rhythm of human fetal breathing movements as well as a relationship to maternal substrate loading. The presence of fetal breathing movements of the rapid irregular type may be a reassuring sign in the presence of other indicators of fetal compromise. Using real-time B-scan imaging, we have found long periods of apnea in pregnancies with normal perinatal outcome. As suggested in the animal studies, changes in fetal breathing patterns prior to fetal death may be more complex than originally thought. The techique of real-time B-scan imaging with precise definition of apnea, general movements, and fetal breathing will provide valuable information on which to base our evaluation of the clinical usefulness of fetal breathing movement studies in the management of pregnancy.

Cervical vascular malformation as a cause of antepartum and intrapartum bleeding in three diethylstilbestrol-exposed progeny

Adverse pregnancy outcome in diethylstilbestrol-exposed progeny has been described by many authors. These three cases demonstrate many of the features discussed in the literature as well as a previously unreported cause of antepartum and intrapartum bleeding: a cervical vascular malformation.

Antepartum fetal heart rate and uterine activity studies: I. Preliminary report of accelerations and the oxytocin challenge test

A series of 344 antepartum fetal heart rate studies in 209 high-risk patients is described. The importance of evaluation of accelerations of the fetal heart rate as well as periodic decelerations associated with uterine activity is demonstrated. Our data suggest that the absence of accelerations of the fetal heart rate during the recording period may be associated with increased perinatal morbidity. Late decelerations may occur in the same recording session as accelerations of the fetal heart rate. The association of late decelerations of the fetal heart rate with no accelerations during the recording session is highly suggestive of increased perinatal morbidity. In high-risk patients, accelerations of the fetal heart rate and no late decelerations with uterine activity are a reassuring finding, with 91 per cent of patients showing no increased perinatal morbidity.

Maternal race, procedures, and infant birth weight in type 2 and gestational diabetes.

OBJECTIVE: To examine the relation between race and cesarean delivery, episiotomy, and low birth weight infants in pregnancies with type 2 and gestational diabetes mellitus and to identify factors that might explain racial differences. METHODS: Population-based, cross-sectional study of 1999–2004 Maryland hospital discharge data. Hospitalizations for delivery of pregnancies with type 2 and gestational diabetes mellitus were identified and matched to infants. The independent variable was maternal race. Dependent variables were cesarean delivery, episiotomy, and low infant birth weight. Stepwise logistic regression models were developed to estimate the independent effect of race on use of each procedure and infant birth weight, after adjusting for sociodemographic, hospital, and clinical factors. RESULTS: We examined 6,310 deliveries for pregnancies with type 2 (15%) and gestational (85%) diabetes. Before adjustment, black race was associated with a higher odds of cesarean delivery (odds ratio [OR] 1.40, 95% confidence interval [CI] 1.24–1.58) and low birth weight infants (OR 1.94, 95% CI 1.57–2.40) compared with white race. Adjustment for racial differences in preeclampsia and fetal heart rate abnormalities accounted for a modest degree of the racial variation in outcomes. With full adjustment, black race was still associated with a higher odds of cesarean delivery (OR 1.38, 95% CI 1.20–1.60) and low birth weight (OR 1.81, 95% CI 1.41–2.34) and a lower odds of episiotomy (OR 0.45, 95% CI 0.36–0.57). CONCLUSION: In pregnancies with diabetes, adjustment for sociodemographic, hospital, and clinical factors only partially explains racial differences in procedure use and infant low birth weight. LEVEL OF EVIDENCE: II-2