Nonclinical parameters affecting primary cesarean rates in the United States.

OBJECTIVE: Cesarean is the single most common operation in United States and has reached epidemic proportions in recent decades. Our objective was to study the effect of nonclinical parameters on primary cesarean rates in a large contemporary population. STUDY DESIGN: We designed a retrospective multicenter study using data obtained from electronic medical records from 19 U.S. hospitals between 2005 and 2007 (Consortium on Safe Labor Database), which included 145,764 term, singleton, nonanomalous, vertex, live births that included labor. The impact of nonclinical parameters (patient and provider characteristics, time of delivery, institutional policies, and insurance type) was investigated using modified Poisson regression methodology and classification and regression tree analysis. RESULTS: There were 125,517 vaginal and 20,247 cesarean deliveries. Using the multivariable model, the nonclinical parameters with statistical significance for primary cesarean were delivery during evening hours, a male provider, public insurance, and nonwhite race (p < 0.001). CONCLUSIONS: Cesarean rates are associated with several nonclinical factors. Further investigation into these factors might help to develop strategies to reduce their influence and hence the rates of cesarean.

Maternal death in the emergency department from trauma.

PURPOSE: Trauma during pregnancy is among leading causes of non-pregnancy-related maternal death (MD). This study describes risk factors for MD from trauma during pregnancy in a large urban population. METHODS: We queried an urban Level One Trauma Center registry for the medical records of pregnant women suffering trauma from 1990 to 2007. Associations were examined between maternal demographics, injury mode details, injury characteristics, and risk of maternal death upon arrival to the emergency room. RESULTS: Overall, 351 patients were identified. Most traumas was caused by motor vehicle collision (71.8 %), accounting for 78.9 % of MD, followed by gun shot wound (10.3 %), stabbing (8.5 %), falls (4.3 %), and assaults (4 %). Abdominal and head injuries were more frequent in cases of MD compared with patients admitted to the hospital (33.3 vs. 25.1 % abdominal, 55.6 vs. 29.4 % head; p < 0.001). A greater proportion of MDs were characterized by lack of restraint use (66.7 %) compared to women admitted to the hospital (47.7 %) and women discharged after observation (43.1 %); p = 0.014. ER deaths had more negative base excess scores than women who were admitted or discharged (-14 vs. -3 vs. -2; p < 0.001), lower blood pH values (6.96 vs. 7.40 vs. 7.44; p < 0.001), greater Injury Severity Scores (ISS) (44.4 vs. 11.49 vs. 2.66; p < 0.001), and lower Revised Trauma Scores (RTS) (0.5 vs. 7.49 vs. 7.83; p < 0.001). CONCLUSIONS: Lack of restraint use in the pregnant population is associated with increased MD. Although not validated in the pregnant population, the ISS and RTS were associated with maternal mortality outcomes.

Duration of membrane rupture and risk of perinatal transmission of HIV-1 in the era of combination antiretroviral therapy.

OBJECTIVE: The objective of the study was to determine whether the duration of membrane rupture of 4 or more hours is a significant risk factor for perinatal transmission of human immunodeficiency virus (HIV) in the era of combination antiretroviral therapy (ART). STUDY DESIGN: This was a prospective cohort study of 717 HIV-infected pregnant women-infant pairs with a delivery viral load available who received prenatal care and delivered at our institution during the interval 1996-2008. RESULTS: The cohort comprised 707 women receiving ART who delivered during this interval. The perinatal transmission rate was 1% in women with membranes ruptured for less than 4 hours and 1.9% when ruptured for 4 or more hours. For 493 women with a delivery viral load less than 1000 copies/mL receiving combination ART in pregnancy, there were no cases of perinatal transmission identified up to 25 hours of membrane rupture. Logistic regression demonstrated only a viral load above 10,000 copies/mL as an independent risk factor for perinatal transmission. CONCLUSION: Duration of membrane rupture of 4 or more hours is not a risk factor for perinatal transmission of HIV in women with a viral load less than 1000 copies/mL receiving combination ART.

The association of gestational weight gain per institute of medicine guidelines and prepregnancy body mass index on outcomes of twin pregnancies.

OBJECTIVE: To determine if current recommendations for weight gain in twin pregnancies according to maternal prepregnancy body mass index (PPBMI) influence perinatal outcomes. METHODS: We identified women with twins enrolled in a maternity risk screening and education program with initial screening and prenatal care initiated at <20 weeks and delivery at >23.9 weeks. Women with normal, overweight, or obese PPBMI were included (n = 5129). Pregnancy outcomes were compared between those women with weight gain meeting or exceeding 2009 Institute of Medicine recommendations and patients who did not meet weight gain guidelines. RESULTS: Rates of spontaneous preterm delivery at <35 weeks were higher in all PPBMI groups for those with weight gain below guidelines. In all PPBMI groups, numbers of pregnancies with both infants weighing >2500 g or >1500 g were significantly higher for women gaining weight at or above guidelines. Logistic regression analysis was utilized to assess multivariate impact on outcome of spontaneous preterm delivery at <35 weeks showing that regardless of PPBMI level, women who gain below recommended guidelines are 50% more likely to deliver spontaneously at <35 weeks. CONCLUSION: In twin pregnancies, weight gain below recommended guidelines determined by maternal PPBMI is associated with higher rates of spontaneous preterm delivery at <35 weeks.

The influence of maternal age on pregnancy outcome in nulliparous women with twin gestation.

We sought to determine if outcomes of nulliparous twin pregnancies differ based on maternal age. Nulliparous women with current twin pregnancies were identified from a database of women enrolled for outpatient nursing surveillance. Data were stratified into four groups by maternal age: less than 20, 20 to 34, 35 to 39, and greater than or equal to 40 years. Maternal and neonatal outcomes for women less than 20, 35 to 39, and 40 or more were compared with 20- to 34-year-old controls using Kruskal-Wallis, Mann-Whitney, and Pearson chi-square analyses. We analyzed 2144 nulliparous twin pregnancies. Patients ≥35 years (34 to 39, 78.5% or ≥40, 85.9%) were more likely to have cesarean deliveries compared with controls 20 to 34 years old (71.2%). Women aged 35 to 39 were less likely to deliver at <37 weeks, and women in the ≥40 group were less likely to deliver at <35 weeks due to spontaneous preterm labor compared with the controls. Neonates born to women aged 35 to 39 had a greater gestational age at delivery and larger average birth weight than controls. Maternal and neonatal outcomes were not adversely influenced by advanced maternal age in nulliparous women carrying twin gestations.

Vasopressin versus a combination of vasopressin and tourniquets: a comparison of blood loss in patients undergoing abdominal myomectomies.

OBJECTIVE: To compare blood loss and need for blood transfusions in women who underwent abdominal myomectomies after receiving vasopressin or combined vasopressin and tourniquet. METHODS: A retrospective chart review was performed reviewing abdominal myomectomies that took place at our institution. Subjects were divided into three groups: no intervention, vasopressin, or combined vasopressin and tourniquet. Blood loss, need for blood transfusion, and drop in hemoglobin and hematocrit were compared across all groups. RESULTS: One-hundred and thirty-two subjects were included in the study. No statistically significant difference was found between groups in blood loss, drop in hemoglobin or hematocrit, or blood transfusions. CONCLUSION: Combined vasopressin and tourniquets was not associated with a statistically significant decrease in blood loss or need for blood transfusion.

Impact of prior gestational age at preterm delivery on effectiveness of 17-alpha-hydroxyprogesterone caproate in practice.

OBJECTIVE: We sought to examine if 17-alpha-hydroxyprogesterone caproate (17OHPC) effectiveness is dependent on the earliest gestational age (GA) at prior spontaneous preterm birth (SPTB) when administered in the clinical setting. STUDY DESIGN: Women enrolled for outpatient services with current singleton gestation and > or =1 prior SPTB between 20-36.9 weeks were identified. Data were divided into 3 groups according to earliest GA of prior SPTB (20-27.9, 28-33.9, and 34-36.9 weeks). We compared GA at delivery of current pregnancy and incidence of recurrent SPTB between women enrolled in outpatient 17OHPC administration program (n = 2978) and women receiving other outpatient services without 17OHPC (n = 1260). RESULTS: Rates of recurrent SPTB for those with and without 17OHPC prophylaxis, respectively, according to GA at earliest SPTB were: 20-27.9 weeks at earliest SPTB, 32.2% vs 40.7%, P = .025; 28-33.9 weeks at earliest SPTB, 34.1% vs 45.5%, P < .001; and 34-36.9 weeks at earliest SPTB, 29.3% vs 38.8%, P < .001. CONCLUSION: 17OHPC given to prevent recurrent SPTB is effective regardless of GA at earliest SPTB.

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.

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.

Caudal dysplasia syndrome and sirenomelia: are they part of a spectrum?

Caudal dysplasia syndrome (CDS) is associated with hypoplastic lower extremities, caudal vertebrae, sacrum, neural tube, and urogenital organs. Sirenomelia is characterized by a single lower extremity, absent sacrum, urogenital anomalies, and imperforate anus. There is controversy in the medical literature about whether sirenomelia and CDS are part of the spectrum of the same malformation. Patients with CDS and sirenomelia were identified from our pathology files from 1991 to 2006. Maternal history, pathologic examination, and radiographs were collected and tabulated. We found 9 cases with CDS and 6 with sirenomelia. Fully 7 of 9 patients with CDS (77.7%) versus none of sirenomelic babies were infants of diabetic mothers. Congenital heart disease was present in 5 patients with CDS (55.5%) and none of the infants with sirenomelia. Of 9 children with CDS 2 (22.2%) had bilateral renal agenesis versus 66% of sirenomelics. Single umbilical artery was found in 33% of cases with CDS and 100% of children with sirenomelia. External genitalia were ambiguous in 2 of 9 patients (22.2%) with CDS and in all patients with sirenomelia. Imperforate anus was found in 10 cases (66.6%) divided as 4 of 9 babies with CDS (44.4%) and all patients with sirenomelia. Three patients with CDS had concomitant maternal diabetes mellitus and chronic hypertension. These babies also had cleft lip and palate. Congenital heart disease was found in 55.5% of cases with CDS and none of the children with sirenomelia. We conclude that although CDS and sirenomelia share many similar features, they are two different entities.

Fetal growth rates and the very preterm delivery of twins.

OBJECTIVE: Our objective was to determine whether slow fetal growth rates and twin growth patterns from 20 weeks' gestation to delivery are associated with very preterm delivery. STUDY DESIGN: Available charts were reviewed for twin pregnancies, delivered between 1979 and 2002, at 4 U.S. medical centers. The sample of 1612 pregnancies delivered at 28 week's gestation or greater and had at least 2 ultrasound evaluations of fetal size from 20 to 28 weeks or from 28 weeks to delivery for estimation of fetal growth rates (grams per week). Slow fetal growth (below the 10th percentile) was defined as less than 90 grams per week at 20-28 weeks and 168 g/week from 28 weeks to delivery. The main outcome measure was the timing of delivery. RESULTS: Of the women delivering twins, 5.3% delivered extremely preterm (28-30 weeks), 8.5% very preterm (31-32 weeks), and 40.1% preterm (33-36 weeks). Patterns of growth for the pair were highly associated with very preterm delivery. Compared with neither growing slowly (1.7%), 4.9% delivered very preterm if only 1 twin grew slowly. Very preterm was 14.6% (adjusted odds ratio 9.81; 95% confidence interval, 3.50-27.48) with both growing slowly from 28 weeks on and 20.0% (adjusted odds ratio 15.04; 95% confidence interval 5.13-44.11) with both growing slowly over both intervals. Survival analyses indicated that twins with normal growth in both intervals remained undelivered for a significantly longer number of days (P < .0001) than pairs in which one or both twins were growing slowly. CONCLUSION: Very preterm delivery of twins seems to be preceded by slowed or compromised fetal growth for the pair.

The Hispanic paradox in twin pregnancies.

The objective of this study was to compare length of gestation, fetal growth, and birthweight by race/ethnicity and pregravid weight groups in twin pregnancies. Three thousand and thirty-six twin pregnancies of 28 weeks or more gestation were divided by race/ethnicity (White, Black and Hispanic), and pregravid body mass index (BMI) groups (less than 25.0 vs. 25.0 or more). Outcomes were modeled using multiple regression, controlling for confounders, with White non-Hispanic women as the reference group. Hispanic women had the highest average birthweight and the longest gestation, as well as the lowest proportions of low birthweight, very low birthweight, preterm and early preterm births of the 3 race/ethnicity groups. In the multivariate analyses, Hispanic women had significantly longer gestations (by 7.8 days) and faster rates of fetal growth midgestation (20 to 28 weeks, by 17.4 g/week) and late gestation (after 28 weeks, by 5.3 g/week), whereas Black women had significantly slower rates of fetal growth (by 5.7 g/week and by 4.5 g/week, respectively). These findings in twins reflect the racial and ethnic disparities previously shown in singletons, including the Hispanic paradox of longer gestations and higher rates of fetal growth.

Elevated maternal glucose concentrations and placental infection in twin pregnancies.

OBJECTIVE: To evaluate the association between maternal screening glucose concentration and placental infection in nondiabetic twin pregnancies. STUDY DESIGN: One thousand sixty-one nondiabetic twin pregnancies at > or =28 weeks' gestation were divided into 3 groups based on the screening 50-g fasting glucose concentration at 24-28 weeks: lowest quartile (< 96 mg/dL), middle 2 quartiles (96-128 mg/dL) and upper quartile (> 128 mg/dL). Outcomes were modeled using general linear and multinomial logistic regression, controlling for confounding factors. RESULTS: The middle and highest glucose groups were associated with increased risks for clinical chorioamnionitis (adjusted OR [AOR] 3.18, 95% CI 1.34, 7.54; AOR 6.80, CI 1.89, 24.53, respectively). Birth at <32 weeks and histologic diagnosis of placental infection (chorioamnionitis, funisitis, necrosis, vasculitis or villitis) were significantly associated only with the highest glucose group (AOR 1.79, CI 1.02, 3.13; AOR 6.95, CI 1.10, 8.68, respectively). CONCLUSION: Elevated screening glucose in nondiabetic twin pregnancies may be a marker of placental inflammation and infection.

Giant cell bone tumor of the thoracic spine presenting in late pregnancy.

BACKGROUND: We report a case of a large giant cell tumor of the thoracic spine presenting with spinal cord compression during pregnancy. CASE: A 24-year-old woman presented at term with lower back pain, bilateral lower extremity weakness, numbness, and bowel and bladder incontinence. Magnetic resonance imaging revealed a spinal soft tissue mass compressing the spinal cord. The patient delivered a healthy girl by cesarean then underwent a T8-T9 laminectomy, posterior spinal decompression, and instrument fusion. Two days later, she had a thoracotomy, corpectomy of the vertebral body, and anterior tumor debulking. Ultimately, the patient was discharged to inpatient rehabilitation with improved lower extremity strength and returned bowel and bladder function. CONCLUSION: Obstetricians should be vigilant regarding progressive neurologic symptoms during pregnancy.

A comparison of obstetric maneuvers for the acute management of shoulder dystocia.

OBJECTIVE: To assess the efficacy of obstetric maneuvers for resolving shoulder dystocia and the effect that these maneuvers have on neonatal injury when shoulder dystocia occurs. METHODS: Using an electronic database encompassing 206,969 deliveries, we identified all women with a vertex fetus beyond 34 0/7 weeks of gestation who incurred a shoulder dystocia during the process of delivery. Women whose fetuses had a congenital anomaly and women with an antepartum stillbirth were excluded. Medical records of all cases were reviewed by trained abstractors. Cases involving neonatal injury (defined as brachial plexus injury, clavicular or humerus fracture, or hypoxic-ischemic encephalopathy or intrapartum neonatal death attributed to the shoulder dystocia) were compared with those without injury. RESULTS: Among 132,098 women who delivered a term cephalic liveborn fetus vaginally, 2,018 incurred a shoulder dystocia (1.5%), and 101 (5.2%) of these incurred a neonatal injury. Delivery of the posterior shoulder was associated with the highest rate of delivery when compared with other maneuvers (84.4% compared with 24.3-72.0% for other maneuvers; P<.005 to P<.001) and similar rates of neonatal injury (8.4% compared with 6.1-14.0%; P=.23 to P=.7). The total number of maneuvers performed significantly correlated with the rate of neonatal injury (P<.001). CONCLUSION: Delivery of the posterior shoulder should be considered following the McRoberts maneuver and suprapubic pressure in the management of shoulder dystocia. The need for additional maneuvers was associated with higher rates of neonatal injury.

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 95 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.

Elevated plasma endothelial microparticles: preeclampsia versus gestational hypertension.

OBJECTIVE: Elevated plasma endothelial microparticle levels have been found to be elevated in women with preeclampsia. However, their role in distinguishing preeclampsia from gestational hypertension remains to be elucidated. The objectives of this study were to compare endothelial microparticle levels among patients with preeclampsia, gestational hypertension, and healthy pregnant control subjects and to evaluate the effect of plasma from women with preeclampsia and gestational hypertension on the release of endothelial microparticles by renal microvascular endothelial cells. STUDY DESIGN: A prospective study was conducted on 52 women with preeclampsia, 20 women with gestational hypertension, and 38 healthy pregnant control subjects. Endothelial microparticles were measured by flow cytometry with fluorescent monoclonal mouse anti-human antibodies against CD31, CD42b, and CD62E. RESULTS: CD31 + /42b - endothelial microparticle levels were 10497 +/- 5145 counts/microL in women with preeclampsia versus 6768 +/- 1810 counts/microL in women with gestational hypertension ( P < .01). In control subjects, CD31 + /42b - endothelial microparticle levels were 6119 +/- 3592 counts/microL. CD62E + endothelial microparticle levels were 1930 +/- 966 counts/microL in women with preeclampsia versus 822 +/- 150 counts/microL in women with gestational hypertension ( P <.01). In control subjects, CD62E + endothelial microparticle levels were 712 +/- 160 counts/microL. Incubation of renal microvascular endothelial cells with plasma from women with preeclampsia resulted in a rise in CD31 + and CD62E + endothelial microparticle levels as compared with women with gestational hypertension and control subjects. CONCLUSION: Endothelial microparticle levels are higher in women with preeclampsia than in women with gestational hypertension and control subjects. The measurement of endothelial microparticles may be useful as a diagnostic tool for preeclampsia in pregnant women.