Shoshana Haberman

Cesarean Scar Ectopic Pregnancies: Etiology, Diagnosis, and Management

OBJECTIVE: To clarify the appropriate way to diagnose and treat an ectopic pregnancy in the uterine scar of a prior cesarean delivery. DATA SOURCES: Articles written in English that were published from January 1966 to August 2005 and quoted in the computerized database MEDLINE/PubMed retrieved by using the words “cesarean section,” “cesarean delivery,” “cesarean section scar pregnancy,” and “ectopic pregnancy.” Additional articles were obtained from reference lists of pertinent case reports and reviews. METHODS OF STUDY SELECTION: Fifty-nine articles that met the inclusion criteria provided data on the clinical presentation, diagnosis, and treatment modalities of 112 cases of cesarean delivery scar pregnancies. TABULATION, INTEGRATION, AND RESULTS: Review of the 112 cases revealed a considerable increase in the incidence of this condition over the last decade, with a current range of 1:1,800 to 1:2,216 normal pregnancies. More than half (52%) of the reported cases had only one prior cesarean delivery. The mean gestational age was 7.5 ± 2.5 weeks, and the most frequent symptom was painless vaginal bleeding. Endovaginal ultrasonography was the diagnostic method in most cases, with a sensitivity of 84.6% (95% confidence interval 0.763–0.905). Expectant management of 6 patients resulted in uterine rupture that required hysterectomy in 3 patients. Dilation and curettage was associated with severe maternal morbidity. Wedge resection and repair of the implantation site via laparotomy or laparoscopy were successful in 11 of 12 patients. Simultaneous administration of systemic and intragestational methotrexate to 5 women, all with β-hCG exceeding 10,000 milli-International Units/mL required no further treatment. CONCLUSION: Surgical treatment or combined systemic and intragestational methotrexate were both successful in the management of cesarean delivery scar pregnancy. Because subsequent pregnancies may be complicated by uterine rupture, the uterine scar should be evaluated before, as well as during, these pregnancies.

Contemporary cesarean delivery practice in the United States

OBJECTIVE To describe contemporary cesarean delivery practice in the United States. STUDY DESIGN Consortium on Safe Labor collected detailed labor and delivery information from 228,668 electronic medical records from 19 hospitals across the United States, 2002-2008. RESULTS The overall cesarean delivery rate was 30.5%. The 31.2% of nulliparous women were delivered by cesarean section. Prelabor repeat cesarean delivery due to a previous uterine scar contributed 30.9% of all cesarean sections. The 28.8% of women with a uterine scar had a trial of labor and the success rate was 57.1%. The 43.8% women attempting vaginal delivery had induction. Half of cesarean for dystocia in induced labor were performed before 6 cm of cervical dilation. CONCLUSION To decrease cesarean delivery rate in the United States, reducing primary cesarean delivery is the key. Increasing vaginal birth after previous cesarean rate is urgently needed. Cesarean section for dystocia should be avoided before the active phase is established, particularly in nulliparous women and in induced labor.

Contemporary Patterns of Spontaneous Labor With Normal Neonatal Outcomes

OBJECTIVE: To use contemporary labor data to examine the labor patterns in a large, modern obstetric population in the United States. METHODS: Data were from the Consortium on Safe Labor, a multicenter retrospective study that abstracted detailed labor and delivery information from electronic medical records in 19 hospitals across the United States. A total of 62,415 parturients were selected who had a singleton term gestation, spontaneous onset of labor, vertex presentation, vaginal delivery, and a normal perinatal outcome. A repeated-measures analysis was used to construct average labor curves by parity. An interval-censored regression was used to estimate duration of labor, stratified by cervical dilation at admission and centimeter by centimeter. RESULTS: Labor may take more than 6 hours to progress from 4 to 5 cm and more than 3 hours to progress from 5 to 6 cm of dilation. Nulliparous and multiparous women appeared to progress at a similar pace before 6 cm. However, after 6 cm, labor accelerated much faster in multiparous than in nulliparous women. The 95th percentiles of the second stage of labor in nulliparous women with and without epidural analgesia were 3.6 and 2.8 hours, respectively. A partogram for nulliparous women is proposed. CONCLUSION: In a large, contemporary population, the rate of cervical dilation accelerated after 6 cm, and progress from 4 cm to 6 cm was far slower than previously described. Allowing labor to continue for a longer period before 6 cm of cervical dilation may reduce the rate of intrapartum and subsequent repeat cesarean deliveries in the United States. LEVEL OF EVIDENCE: III

Maternal and neonatal outcomes by labor onset type and gestational age

OBJECTIVE We sought to determine maternal and neonatal outcomes by labor onset type and gestational age. STUDY DESIGN We used electronic medical records data from 10 US institutions in the Consortium on Safe Labor on 115,528 deliveries from 2002 through 2008. Deliveries were divided by labor onset type (spontaneous, elective induction, indicated induction, unlabored cesarean). Neonatal and maternal outcomes were calculated by labor onset type and gestational age. RESULTS Neonatal intensive care unit admissions and sepsis improved with each week of gestational age until 39 weeks (P < .001). After adjusting for complications, elective induction of labor was associated with a lower risk of ventilator use (odds ratio [OR], 0.38; 95% confidence interval [CI], 0.28-0.53), sepsis (OR, 0.36; 95% CI, 0.26-0.49), and neonatal intensive care unit admissions (OR, 0.52; 95% CI, 0.48-0.57) compared to spontaneous labor. The relative risk of hysterectomy at term was 3.21 (95% CI, 1.08-9.54) with elective induction, 1.16 (95% CI, 0.24-5.58) with indicated induction, and 6.57 (95% CI, 1.78-24.30) with cesarean without labor compared to spontaneous labor. CONCLUSION Some neonatal outcomes improved until 39 weeks. Babies born with elective induction are associated with better neonatal outcomes compared to spontaneous labor. Elective induction may be associated with an increased hysterectomy risk.

The maternal body mass index: a strong association with delivery route.

OBJECTIVE We sought to assess body mass index (BMI) effect on cesarean risk during labor. STUDY DESIGN The Consortium on Safe Labor collected electronic data from 228,668 deliveries. Women with singletons > or = 37 weeks and known BMI at labor admission were analyzed in this cohort study. Regression analysis generated relative risks for cesarean stratifying for parity and prior cesarean while controlling for covariates. RESULTS Of the 124,389 women, 14.0% had cesareans. Cesareans increased with increasing BMI for nulliparas and multiparas with and without a prior cesarean. Repeat cesareans were performed in > 50% of laboring women with a BMI > 40 kg/m(2). The risk for cesarean increased as BMI increased for all subgroups, P < .001. The risk for cesarean increased by 5%, 2%, and 5% for nulliparas and multiparas with and without a prior cesarean, respectively, for each 1-kg/m(2) increase in BMI. CONCLUSION Admission BMI is significantly associated with delivery route in term laboring women. Parity and prior cesarean are other important predictors.

Characteristics Associated With Severe Perineal and Cervical Lacerations During Vaginal Delivery

OBJECTIVE: To characterize potentially modifiable risk factors for third- or fourth-degree perineal lacerations and cervical lacerations in a contemporary U.S. obstetric practice. METHODS: The Consortium on Safe Labor collected electronic medical records from 19 hospitals within 12 institutions (228,668 deliveries from 2002 to 2008). Information on patient characteristics, prenatal complications, labor and delivery data, and maternal and neonatal outcomes were collected. Only women with successful vaginal deliveries of cephalic singletons at 34 weeks of gestation or later were included; we excluded data from sites lacking information about lacerations at delivery and deliveries complicated by shoulder dystocia; 87,267 and 71,170 women were analyzed for third- or fourth-degree and cervical lacerations, respectively. Multivariable logistic regressions were used to adjust for other factors. RESULTS: Third- or fourth-degree lacerations occurred in 2,516 women (2,223 nulliparous [5.8%], 293 [0.6%] multiparous) and cervical lacerations occurred in 536 women (324 nulliparous [1.1%], 212 multiparous [0.5%]). Risks for third- or fourth-degree lacerations included nulliparity (7.2-fold risk), being Asian or Pacific Islander, increasing birth weight, operative vaginal delivery, episiotomy, and longer second stage of labor. Increasing body mass index was associated with fewer lacerations. Risk factors for cervical lacerations included young maternal age, vacuum vaginal delivery, and oxytocin use among multiparous women, and cerclage regardless of parity. CONCLUSION: Our large cohort of women with severe obstetric lacerations reflects contemporary obstetric practices. Nulliparity and episiotomy use are important risk factors for third- or fourth-degree lacerations. Cerclage increases the risk for cervical lacerations. Many identified risk factors may not be modifiable. LEVEL OF EVIDENCE: II

Determination of fetal head station and position during labor : a new technique that combines ultrasound and a position-tracking system

OBJECTIVE The purpose of this study was to compare the ultrasound-based LaborPro (Trig Medical Ltd, Yokneam, Israel) system determination of fetal head station and position with routine vaginal examination. STUDY DESIGN This prospective study, which was conducted in 3 centers included 311 measurements that were performed in 166 singleton term pregnancies during the active phase of vertex, uncomplicated labor. Ultrasound-based position-tracking system calculations of fetal head station and position were compared with routine vaginal examination measurements. RESULTS Comparison of vaginal examination with the system head station results revealed a mean absolute difference of 5.5 +/- 6.1 mm (n = 311). Vaginal examination head-position evaluation, within a 45 degrees interval, complied with the system in 35 of 87 cases (40.2%). CONCLUSION Our data show that an ultrasound-based system can determine fetal head station and position during labor, when compared with vaginal examination, and requires minimal ultrasound skills. The limits of vaginal examination assessment of the head position are in agreement with published data.

Variations in compliance with documentation using computerized obstetric records.

OBJECTIVE: To explore factors that affect documentation completeness using an electronic medical record with a decision support system for obstetrics. METHODS: Two thousand eight hundred nine consecutive deliveries were analyzed and data were obtained from structured fields in the decision support system. The decision support system was customized to deactivate the systems repetitive prompts and reminders for documentation completeness for the chosen study parameters. Completion of documentation for estimated fetal weight, pelvic adequacy, and fetal position were selected as outcome variables. One point was given for each missing item. Data were analyzed using general linear univariable models. Tukeys honest difference method was used to adjust the P values for potential multiple comparison biases. RESULTS: Midwives had fewer missing items (score 1.42) than both attendings (1.87) and residents (1.74), P<.01. When comparing the following groups, the mean scores differed significantly: vaginal birth after cesarean and repeat cesarean delivery, 1.95 and 1.83 (P<.04); neonatal intensive care unit admission and regular nursery, 1.96 and 1.82 (P<.05). Patients experiencing normal and abnormal labors were similar in documentation completeness, but patients who lacked enough data to have their labors classified were significantly less likely to have complete documentation for the chosen outcome variables. CONCLUSION: Compliance with documentation in electronic medical record is very low when the reminders for documentation completeness are deactivated and varies with type of provider, as well as with some clinical aspects of the patient. LEVEL OF EVIDENCE: III

Neonatal serum magnesium concentrations are determined by total maternal dose of magnesium sulfate administered for neuroprotection.

Abstract Background: Antenatal magnesium in preterm labor for neuroprotection decreases the incidence of cerebral palsy. However, there are no guidelines on the dose and duration of magnesium infusion for neuroprotection. As increased neonatal serum magnesium concentrations may be related to higher risk of morbidity and mortality, the role of total amount of magnesium and maternal serum magnesium concentrations associated with safe neonatal serum magnesium concentrations is not known. Methods: A retrospective study was conducted on 289 mothers who received antenatal magnesium for neuroprotection as a loading dose of 4–6 g infused over 30 min, followed by a maintenance infusion of 1–2 g/h. Total magnesium dose infused to the mother and maternal serum magnesium concentrations were correlated with neonatal serum magnesium concentrations. Results: Of the 289 mothers, 192 mother/baby dyads had all three measurements (maternal total magnesium dose, and maternal and neonatal serum magnesium concentrations). Magnesium infusion was continued beyond 24 h in 60 mothers. Total maternal magnesium dose at 24 and 48 h of infusion correlated with neonatal serum magnesium concentrations (r=0.55, P<0.0001 and r=0.35, P<0.0001, respectively), but not with maternal serum magnesium concentrations (r=0.004, P=0.98 and r=0.14, P=0.21). However, there was no correlation between the maternal and neonatal serum magnesium concentrations (r=0.10, P=0.15). Conclusion: Total dose of magnesium infused to the mother correlates with neonatal serum magnesium concentrations. To keep neonatal serum magnesium concentrations within a range that is effective for neuroprotection and safe for the neonates, the total dose received by the mother needs to be monitored and limited.

How reliable is the determination of cervical dilation? Comparison of vaginal examination with spatial position-tracking ruler

OBJECTIVE The purpose of this study was to evaluate the accuracy of clinical measurement of cervical dilation with a position-tracking system during vaginal examination. STUDY DESIGN This prospective study that was conducted in Poissy, France, Brooklyn, NY, and Haifa, Israel, included 333 measurements that were performed in 188 women with term singleton vertex uncomplicated pregnancies during the active stage of labor. Ninety measurements with clinical diagnosis of full dilation were excluded from analysis. Measurements were performed with a sensor attached to the midwifes index fingertip and a position-tracking system that was based on a low magnetic field. Evaluations were done when cervical examinations were clinically indicated. RESULTS Results were similar in all centers. Mean error was 10.2 +/- 8.4 mm and ranged from 7.5 +/- 7.3 mm, when cervical dilation was > 8 cm, to 12.5 +/- 8.7 mm when cervical dilation was between 6.1 and 8 cm. CONCLUSION This first evaluation of cervical assessment accuracy during vaginal examination with a position-tracking system shows limited precision.