Jennifer L. Bailit

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.

Outcomes of women presenting in active versus latent phase of spontaneous labor.

OBJECTIVE: To evaluate outcome differences between women presenting in latent and active labor. METHODS: We evaluated all low-risk women with term, singleton, vertex gestations who presented in active phase or latent phase labor at MetroHealth Medical Center from January 1993 to June 2001. Baseline characteristics were compared. Labor outcomes were assessed by logistic regression, controlling for parity. RESULTS: A total of 6,121 active phase and 2,697 latent phase women met the study criteria. More latent phase women were nulliparous (51 compared with 28%). Latent phase women had more cesarean deliveries (nulliparas 14.2% compared with 6.7%, multiparas 3.1% compared with 1.4%). Controlling for parity, latent phase women had more active phase arrest (odds ratio [OR] 2.2), oxytocin use (OR 2.3), scalp pH performed (OR 2.2), intrauterine pressure catheter placed (OR = 2.2), fetal scalp electrocardiogram monitoring (OR = 1.7), and amnionitis (OR 2.7) (P < .001 for each). CONCLUSION: It is uncertain whether inherent labor abnormalities resulted in latent phase presentation and subsequent physician intervention or early presentation and subsequent physician intervention are the cause of labor abnormalities. LEVEL OF EVIDENCE: III

A statewide initiative to reduce inappropriate scheduled births at 36(0/7)-38(6/7) weeks' gestation.

OBJECTIVE We sought to reduce scheduled births between 36(0/7)-38(6/7) weeks that lack appropriate medical indication. STUDY DESIGN Twenty Ohio maternity hospitals collected baseline data for 60 days and then selected locally appropriate Institute for Healthcare Improvement Breakthrough Series interventions to reduce the incidence of scheduled births. Deidentified birth data were analyzed centrally. Rates of scheduled births without a documented indication, birth certificate data, and implementation issues were shared regularly among sites. RESULTS The rate of scheduled births between 36(0/7)-38(6/7) weeks without a documented medical indication declined from 25% to <5% (P < .05) in participating hospitals. Birth certificate data showed inductions without an indication declined from a mean of 13% to 8% (P < .0027). Dating criteria were documented in 99% of charts. CONCLUSION A statewide quality collaborative was associated with fewer scheduled births lacking a documented medical indication.

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

The effect of house staff working hours on the quality of obstetric and gynecologic care

OBJECTIVE: To measure the effect of house staff working hours reforms on the quality of obstetric and gynecologic care. METHODS: Sentinel events, medication errors, maternal and neonatal outcomes, and decision making were measured before and after the Accreditation Council of Graduate Medical Education work-hour reforms. Data sources consisted of the perinatal database at MetroHealth Medical Center (Case Western Reserve University, Cleveland, OH), incident reports filed in the hospital department of risk management, the patient-satisfaction database at MetroHealth Medical Center, and the pharmacy medication error database. Two reviewers examined all incident reports separately, and discrepancies were resolved by mutual agreement. RESULTS: Patient demographics did not change across the 2 time periods. Obstetric outcomes were the same for third- and fourth-degree lacerations, umbilical arterial pH less than 7, fever, and the need for general anesthesia. Postpartum hemorrhage and neonatal resuscitations were significantly decreased over time (2% before versus 1% after work-hour restrictions [P = .008], and 30% before versus 26% after work-hour restrictions [P < .001], respectively). The rate of primary cesarean delivery rose from 14% to 16%, a nonsignificant difference (P < .06). There were no differences in rates of cesarean delivery for nonreassuring fetal status, failed induction, labor abnormality, or repeat cesarean delivery. Reported medication errors associated with resident performance were too rare for comparison across time periods. The number of incident reports directly involving residents before and after work-hour restrictions were 3 and 10, respectively—too few to reach statistical significance. CONCLUSIONS: Although problems in physician performance may be underreported, resident work-hour restrictions show minimal evidence of improvement in quality of care. LEVEL OF EVIDENCE: II-3

Frequency of and factors associated with severe maternal morbidity

OBJECTIVE: To estimate the frequency of severe maternal morbidity, assess its underlying etiologies, and develop a scoring system to predict its occurrence. Supplemental Digital Content is Available in the Text. METHODS: This was a secondary analysis of a Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network cohort of 115,502 women and their neonates born in 25 hospitals across the United States over a 3-year period. Women were classified as having severe maternal morbidity according to a scoring system that takes into account the occurrence of red blood cell transfusion (more than three units), intubation, unanticipated surgical intervention, organ failure, and intensive care unit admission. The frequency of severe maternal morbidity was calculated and the underlying etiologies determined. Multivariable analysis identified patient factors present on admission that were independently associated with severe maternal morbidity; these were used to develop a prediction model for severe maternal morbidity. RESULTS: Among 115,502 women who delivered during the study period, 332 (2.9/1,000 births, 95% confidence interval 2.6–3.2) experienced severe maternal morbidity. Postpartum hemorrhage was responsible for approximately half of severe maternal morbidity. Multiple patient factors were found to be independently associated with severe maternal morbidity and were used to develop a predictive model with an area under the receiver operating characteristic curve of 0.80. CONCLUSION: Severe maternal morbidity occurs in approximately 2.9 per 1,000 births, is most commonly the result of postpartum hemorrhage, and occurs more commonly in association with several identifiable patient characteristics. LEVEL OF EVIDENCE: II

Risk adjustment for interhospital comparison of primary cesarean rates

OBJECTIVE To create a method of controlling for case mix so that inferences could be made about variation in cesarean rates among hospitals. METHODS A total of 160,753 births from 1991 Illinois birth certificate data were analyzed. A multivariate model of characteristics independently associated with cesarean delivery was developed from a random 25% sample, validated on the other 75%, and used to create a probability of cesarean delivery for each woman. The validated model was used to calculate a predicted primary cesarean delivery rate for the 154 hospitals in Illinois that did at least 100 deliveries per year. RESULTS The final model included both medical and sociodemographic risk factors and predicted primary cesarean rates accurately over a full range of rates. Thirty-five hospitals (23%) had actual rates that were higher than their individual predicted 95% confidence interval (CI). Eighty-nine hospitals (58%) had actual rates within predicted CIs. Thirty hospitals (20%) had actual rates that were lower than the predicted 95% CI. Twenty-three percent of hospitals with actual rates greater than predicted rates were not in the top quartile of actual rates. Twenty-seven percent of hospitals with actual rates in the top quartile were doing cesarean deliveries appropriate for the risk status of the population served. CONCLUSION Risk adjusting for hospital case mix more accurately identifies outlier hospitals than raw, unadjusted primary cesarean delivery rates. We believe that risk adjusting should be the first step in understanding variations in primary cesarean delivery rates.