Influence of Estimated Fetal Weight on Labor Management.

OBJECTIVE: Prior studies suggest knowledge of estimated fetal weight (EFW), particularly by ultrasound (US), increases the risk for cesarean delivery. These same studies suggest that concern for macrosomia potentially alters labor management leading to increased rates of cesarean delivery. We aimed to assess if shortened labor management, as a result of suspected macrosomia (≥4,000 g), leads to an increased rate of cesarean delivery. STUDY DESIGN: This is a secondary analysis of a retrospective cohort study at a single tertiary center in 2015 of women with singleton pregnancies ≥36 weeks with documented EFW by US within 3 weeks or physical exam on admission. Women were excluded if an initial cervical exam was ≥6 cm or no attempt was made to labor. In addition, patients were excluded for the diagnosis of hypertension, diabetes, or prior cesarean delivery, as these comorbidities influence the use of US, labor management, and cesarean delivery independent of fetal weight. Patients were classified as EFW of ≥4,000 and <4,000 g. Secondary analysis examined the impact of US within 3 weeks of admission when compared with physical exam at the time of admission. The primary maternal outcomes were duration of labor and cesarean delivery. Duration of labor was evaluated as total time from 4 cm to delivery (with 4-cm dilation being a surrogate marker for active labor), length of time allowed from 4 cm until the first documented cervical change (or delivery), and time in second stage of labor (complete dilation to delivery). Cesarean delivery for arrest of labor was a secondary outcome. Student's t-test, Mann-Whitney U-test, chi-squared test, and Fisher's exact test were used for univariate data analysis as appropriate. RESULTS: Of 1,506 patients included, 54 (3.5%) had EFW of ≥4,000 g. Women with EFW of ≥4,000 g had a larger body mass index, higher fetal birth weight, were more likely to be undergoing induction of labor, had a more advanced gestational age, and were more likely to have had an US within 3 weeks of delivery. They were more likely to undergo cesarean delivery (29.6 vs. 9.3%, adjusted odds ratio [AOR]: 2.7, 95% confidence interval [CI]: 1.3-5.5) despite not having shortened labor times. When analyzing this population by method of obtaining EFW, those with EFW based on US rather than external palpation were more likely to undergo cesarean delivery (13.1 vs. 7.9%, AOR: 1.5, 95% CI: 1.01-2.12), again without having shortened labor times. CONCLUSION: EFW of ≥4,000 g and use of US to estimate fetal weight do not appear to shorten labor management despite being associated with an increased risk of cesarean delivery.

The Utility of Repeat Midtrimester Anatomy Ultrasound for Anomaly Detection.

INTRODUCTION: Although guidelines recommend repeat ultrasound in the setting of an incomplete fetal anatomic survey, the clinical utility of this practice has not been established. As such, we aimed to assess the yield of repeat ultrasound for anomaly detection following an incomplete survey. MATERIALS AND METHODS: This is a retrospective cohort study of all singletons who underwent a midtrimester anatomic ultrasound at University of Alabama at Birmingham (UAB) from 2006 to 2014. Patients with an incomplete ultrasound underwent repeat examinations until completion. The population was divided into cohorts FIRST, SECOND, and THIRD, corresponding to the ultrasound at which the exam was deemed complete. Each detected anomaly was tallied. The number of ultrasounds needed to detect an anomaly was then assessed per group. RESULTS: Of 15,768 ultrasounds performed on 13,740 patients, 11,828 exams were completed on first attempt; 1,796 patients required a second, while 116 patients required a third scan or more. We detected 324 anomalies; 93.8% in FIRST, 5.9% in SECOND, and 0.3% in THIRD. The number of scans needed to detect an anomaly was 39, 189, and 348 for FIRST, SECOND, and THIRD, respectively. CONCLUSION: Over 90% of anomalies are detected on the initial fetal anatomic survey. The incremental diagnostic yield then decreases, requiring appreciably more repeat scans to detect one anomaly.

Completion and Sensitivity of the Second-Trimester Fetal Anatomic Survey in Obese Gravidas.

OBJECTIVES: To estimate the effect of maternal body mass index (BMI) on the completion of fetal anatomic surveys before 20 weeks' estimated gestational age (GA). METHODS: We conducted a retrospective cohort study of singletons undergoing standard or detailed anatomic sonographic examinations from 2006 to 2014. Patients were categorized by ranges of BMI. The primary outcomes were completion of standard and detailed anatomic surveys before 20 weeks' estimated GA. The effect of the BMI category was assessed by the χ2 test for trends and analysis of variance. RESULTS: Of 15,313 patients, 5917 (38%) were obese, and 1581 (10%) had a BMI of 40 kg/m2 or higher. Standard (P < .01) and detailed (P < .01) surveys were less likely to be completed as the BMI category increased. Suboptimal visualization of the fetal chest (P < .01), abdomen (P < .01), and extremities (P < .01) significantly contributed to the decreased standard survey completion rates. Suboptimal visualization of the fetal head (P < .01) and chest (P < .01) significantly contributed to the decreased detailed survey completion rates. There was no statistically significant difference in the sensitivity of a completed standard or detailed anatomic survey for the detection of fetal anomalies. CONCLUSIONS: An increasing BMI category was associated with decreased completion of standard and detailed anatomic surveys by 20 weeks' estimated GA. Strategies to improve early visualization of the fetal head, chest, and abdomen in obese women should be investigated to promote anomaly detection and appropriate counseling.

The Performance of First-Trimester Anatomy Scan: A Decision Analysis.

Introduction First-trimester ultrasound (US) for anatomy assessment may improve anomaly detection, but it may also increase overall US utilization. We sought to assess the utility of first-trimester US for evaluation of fetal anatomy. Materials and Methods A decision analytic model was created to compare first- plus second-trimester anatomy scans to second-trimester scan alone in four populations: general, normal weight women, obese women, and diabetics. Probability estimates were obtained from the literature. Outcomes considered were number of: major structural anomalies detected, US performed, and false-positive US. Multivariable sensitivity analyses were performed to evaluate the consistency of the model with varying assumptions. Results A strategy of first- plus second-trimester US detected the highest number of anomalies but required more US examinations per anomaly detected. The addition of a first-trimester anatomy US was associated with a small increase in the false-positive US (< 10/10,000). In populations with higher anomaly prevalence and lower second-trimester US sensitivity (i.e., diabetes, obesity), the number of additional US performed per anomaly detected with the first-trimester US was < 60. Discussion In high-risk populations, a first-trimester US in addition to a second-trimester US may be a beneficial approach to detecting anomalies.

Gestational age at delivery and perinatal outcomes of twin gestations.

OBJECTIVE: The optimal gestational duration for twin gestations is unknown. Epidemiologic studies show that the lowest perinatal mortality rate for twins is at 37-38 weeks, but these studies lack information on pregnancy complications and neonatal morbidities. This study evaluates pregnancy characteristics and perinatal outcomes of twins in order to assess the optimal gestational age for delivery. STUDY DESIGN: This is a retrospective study of twins delivered at ≥36 weeks at our institution from 1991-2009. The composite rate of perinatal morbidity and mortality (including perinatal death, respiratory distress, suspected sepsis, and need for neonatal intensive care) was determined for weekly intervals from 36-39(+) weeks. RESULTS: There were 377 twin gestations included. Of those 83% were dichorionic. Fifty-three percent had spontaneous labor and 48% were delivered by cesarean section. Perinatal outcomes improved as gestational age advanced to 38 weeks. CONCLUSION: Perinatal morbidity and mortality rates suggest that the optimal time for delivery of twins is at 38 weeks or greater.

Tocolytic therapy for acute preterm labor.

The pathophysiology leading to preterm labor is not well understood and often multifactorial; initiating factors include intrauterine infection, inflammation, ischemia, overdistension, and hemorrhage. Given these different potential causes, directing therapy for preterm labor has been difficult and suboptimal. To date, no single drug has been identified as successful in treating all of the underlying mechanisms leading to preterm labor. In addition, the methodology of many of the tocolytic studies is limited by lack of sufficient patient numbers, lack of comparison with a placebo, and inconsistent use of glucocorticoids. The limitations in these individual studies make it difficult to evaluate the efficacy of a single tocolytic by meta-analysis. Despite these limitations, the goals for tocolysis for preterm labor are clear: To complete a course of glucocorticoids and secure the appropriate level of neonatal care for the fetus in the event of preterm delivery. The literature demonstrates that many tocolytic agents inhibit uterine contractility. The decision as to which tocolytic agent should be used as first-line therapy for a patient is based on multiple factors, including gestational age, the patient's medical history, common and severe side effects, and a patient's response to therapy. In a patient at less than 32 weeks gestation, indomethacin may be a reasonable first choice based on its efficacy, ease of administration, and minimal side effects. Concurrent administration of magnesium for neuroprotection may be given. At 32 to 34 weeks, nifedipine may be a reasonable first choice because it does not carry the fetal risks of indomethacin at these later gestational ages, is easy to administer, and has limited side effects relative to beta-mimetics. In an effort to review a commonly faced obstetrical complication, this article has provided a summary of the most commonly used tocolytics, their mechanisms of action, side effects, and clinical data regarding their efficacy.

A randomized, double-blinded, controlled trial comparing parenteral normal saline with and without dextrose on the course of labor in nulliparas.

OBJECTIVE: The objective of the study was to compare intravenous normal saline with and without dextrose on the course of labor in nulliparae. STUDY DESIGN: In a double-blinded, controlled trial, term, nulliparae with singletons in active labor were randomized into 1 of 3 groups receiving either normal saline (NS), NS with 5% dextrose (D5NS), or NS with 10% dextrose (D10NS) at 125 mL/h. The primary outcome was total length of labor from onset of study fluid in vaginally delivered subjects. Maternal and neonatal outcomes were also analyzed. RESULTS: Of 300 subjects enrolled, 289 met inclusion criteria and completed the study. In vaginally delivered subjects, significant differences were noted in the second stage (P = .01) and total length of labor (P = .02). No significant differences were observed in the cesarean section rates between the groups (P = .21). No differences were noted in maternal or neonatal secondary outcomes. CONCLUSION: Administration of a dextrose solution, regardless of concentration, was associated with a shortened labor course in term vaginally delivered nulliparae subjects in active labor.

Pathologic uterine torsion associated with placental abruption, maternal shock, and intrauterine fetal demise.

Torsion of the uterus is a rare obstetric complication. This report describes a 270-degree uterine torsion associated with placental abruption, maternal shock, and fetal demise. At laparotomy, the uterus and ovaries were necrotic. This patient presented in a manner typically managed by labor induction, thus delaying her diagnosis of uterine torsion.

Severe preeclampsia at <25 weeks of gestation: maternal and neonatal outcomes.

OBJECTIVE: The purpose of this study was to determine maternal and neonatal outcomes of women who were delivered because of severe preeclampsia before 25 weeks of gestation. STUDY DESIGN: We used a computerized database to identify 3800 women with preeclampsia among 35,937 deliveries from 1991 to 1997. Of these, 39 women (1%) with severe preeclampsia were delivered before 25 weeks of gestation. We abstracted outcomes in these women and their newborns. RESULTS: All 39 women had severe preeclampsia as defined by clinical and/or laboratory criteria. Thirty-three of the 39 women had severe-range hypertension. Twenty-one women (54%) experienced morbidity that included abruptio placentae (n = 5), HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome (n = 9), renal insufficiency (n = 5), and eclampsia (n = 3). No women required dialysis or intensive care unit admission, and none of the women died. All maternal morbidities reversed after delivery. Twenty-two infants (55%) were live-born. Only 4 infants (10%) survived, all with severe handicaps. CONCLUSION: In women with severe preeclampsia before 25 weeks of gestation, delivery is associated with minimal short-term maternal morbidities, although neonatal morbidity and death are appreciable.