The Hassan Neonatal Morbidity Composite Scale and Neonatal Length of Stay-A Validation Study

OBJECTIVE

 Obstetric studies often report neonatal morbidity as a composite score. Composite scores can simplify data analysis when multiple outcomes of interest are present and allows researchers to conduct smaller, more manageable trials. The Hassan scale is a neonatal morbidity composite scale that assigns high scores to infants with multiple morbidities and low scores to infants without or with single morbidities. The objective of this study was to validate the association between scores on the Hassan scale and neonatal intensive care unit (NICU) length of stay STUDY DESIGN:  We conducted a cohort study of all infants born between 22 and 366/7 weeks' gestation and cared for within 419 neonatal units in the Pediatrix Medical Group between 1997 and 2018. Each infant was assigned a Hassan's score based on the number of neonatal morbidity events that occurred during the delivery hospitalization. The association between Hassan's scores and neonatal length of stay was evaluated using linear regression. Multivariable models were constructed to determine if the Hassan score was independently associated with neonatal length of stay.

RESULTS

 There were 760,037 infants included. The median (interquartile range [IQR]) gestational age of delivery was 34 (31, 35) weeks and the median (IQR) birth weight at delivery was 2,000 (1,503, 2,430) g. The median length of stay for infants discharged home was 17 (10-33) days. A Hassan's score was able to be assigned to 699,206 (92%) patients. Neonatal morbidities included in the Hassan scale were more common among infants born earlier in gestation. On adjusted analysis, the Hassan scale was found to be independently associated with neonatal length of stay (p < 0.001, coefficient = 10.4 days [95% confidence interval (CI): 10.3, 10.4 days]) with higher scores associated with longer lengths of stay.

CONCLUSION

 The Hassan scale, more than a binary composite score, is able to differentiate preterm infants with prolonged hospitalizations from those with short hospitalizations.

KEY POINTS

· The Hassan scale is an independent predictor of neonatal length of stay.. · Classification of infants based on number of morbidities correlates with neonatal length of stay.. · The Hassan scale provided better discrimination than binary composite morbidity scores.. · The Hassan scale may be an economic predictor of health-related costs..

Prospective Observational Study of N-terminal Pro-Brain Natriuretic Peptide Levels in Obese and Nonobese Women during Pregnancy

OBJECTIVE

N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of ventricular dysfunction, varies by body mass index (BMI) outside of pregnancy. This study aimed to determine whether obesity affects NT-proBNP levels in pregnancy.

STUDY DESIGN

This was a prospective observational study of healthy pregnant people in the third trimester (3TM) and postpartum (PP). Patients were excluded if they had significant medical comorbidities or if their fetuses had anomalies, growth restriction or aneuploidy. NT-proBNP was measured at 28 weeks (3TM), predelivery (PD), 1 to 2 days PP (immediate postpartum [IPP]), and 4 to 6 weeks PP (delayed postpartum [DPP]). LogNT-proBNP levels were analyzed using linear mixed effects models, including BMI < or ≥30, time, and time-by-BMI interactions.

RESULTS

Fifty-five people (28 [51%] with BMI ≥ 30 and 27 [49%] with BMI < 30) were enrolled. A greater proportion of obese than nonobese subjects developed hypertensive disorders of pregnancy (50 vs. 15%, p = 0.010) and obese patients had higher systolic blood pressures at all time points (p < 0.05). NT-proBNP levels (median [interquartile range] in pg/mL) were 18 (6-28) versus 26 (17-48) at 3TM, 16 (3-38) versus 43 (21-60) at PD, 58 (20-102) versus 63 (38-155) at IPP, and 33 (27-56) versus 23 (8-42) at DPP for obese compared with nonobese patients. In linear mixed effects models, logNT-proBNP was lower in obese patients at 3TM (β = -0.89 [95% confidence interval, CI: -1.51, -0.26]) and PD (β = -1.05 [95% CI: -1.72, -0.38]). The logNT-proBNP trends over time differed by BMI category, with higher values in obese patients at both PP time points compared with the 3TM (IPP β = 1.24 [95% CI: 0.75, 1.73]; DPP β = 1.08 [95% CI: 0.52, 1.63]), but only IPP for nonobese patients (β = 0.87 [95% CI: 0.36, 1.38]).

CONCLUSION

Obese patients had lower NT-proBNP levels than nonobese patients during pregnancy but not PP. The prolonged PP elevation in NT-proBNP in obese patients suggests that their PP cardiac recovery may be more prolonged.

KEY POINTS

· NT-proBNP levels are lower in obese than nonobese patients during pregnancy.. · Levels remain elevated in obese, but not nonobese, patients up to 4 to 6 weeks' postpartum.. · A lower threshold for concern regarding NT-proBNP levels may be needed in obese pregnant people..

Pregnancy-Associated Extracorporeal Membrane Oxygenation in the United States

OBJECTIVE

 The use of extracorporeal membrane oxygenation (ECMO) therapy has increased in the adult population. Studies from the H1N1 influenza pandemic suggest that ECMO deployment in pregnancy is associated with favorable outcomes. With increasing numbers of pregnant women affected by COVID-19 (coronavirus disease 2019) and potentially requiring this life-saving therapy, we sought to compare comorbidities, costs, and outcomes between pregnancy- and nonpregnancy-associated ECMO therapy among reproductive-aged female patients.

STUDY DESIGN

 We used the 2013 to 2019 National Readmissions Database. Diagnosis and procedural coding were used to identify ECMO deployment, potential indications, comorbid conditions, and pregnancy outcomes. The primary outcome was in-hospital mortality during the patient's initial ECMO stay. Secondary outcomes included length of stay and hospital charges/costs, occurrence of thromboembolic or bleeding complications during ECMO hospitalization, and mortality and readmissions up to 330 days following ECMO stay. Univariate and multivariate regression models were used to model the associations between pregnancy status and outcomes.

RESULTS

 The sample included 324 pregnancy-associated hospitalizations and 3,805 nonpregnancy-associated hospitalizations, corresponding to national estimates of 665 and 7,653 over the study period, respectively. Pregnancy-associated ECMO had lower incidence of in-hospital death (adjusted odds ratio [aOR]: 0.56, 95% confidence interval [CI]: 0.41-0.75) and bleeding complications (aOR: 0.67, 95% CI: 0.49-0.93). Length of stay was significantly shorter (adjusted rate ratio (aRR): 0.86, 95% CI: 0.77-0.96) and total hospital costs were less (aRR: 0.83, 95% CI: 0.75-0.93). Differences in the incidence of thromboembolic events (aOR: 1.04, 95% CI: 0.78-1.38) were not statistically significant.

CONCLUSION

 Pregnancy-associated ECMO therapy had lower incidence of in-hospital death, bleeding complications, total inpatient cost, and length of stay when compared with nonpregnancy-associated ECMO therapy without increased thromboembolic complications. Pregnancy-associated ECMO therapy should be offered to eligible patients.

KEY POINTS

· Pregnancy-related ECMO use was compared with nonpregnant use.. · Outcomes were equal or favored pregnancy-related deployment.. · These data may be useful when considering ECMO use in pregnancy..

Obstructive Sleep Apnea Among Gravidas With Chronic Hypertension Compared to Matched Controls: A Prospective Cohort Study

BACKGROUND

Previous studies of obstructive sleep apnea (OSA) risk in gravidas with chronic hypertension (cHTN) did not control for obesity as a risk factor for OSA. We therefore performed this study to evaluate whether OSA is more prevalent among gravidas with cHTN compared to normotensive gravidas matched for body mass index (BMI) and gestational age (primary outcome). We also assessed whether OSA is more severe when comorbid with cHTN in pregnancy (secondary outcome).

METHODS

This was a single-center, prospective cohort study. Adult gravidas at 10-20 weeks of gestation, with and without cHTN, were enrolled and BMI matched. All subjects answered OSA screening questionnaires and underwent a home sleep test when they were between 10 and 20 weeks of gestation. Pregnancy outcomes were followed for all subjects. We performed univariable and multivariable logistic regression to model the relationship between cHTN status and OSA.

RESULTS

A total of 100 pregnant subjects (50 with cHTN and 50 normotensive) completed a home sleep test of 2 hours or more. There were no differences in demographic variables between the 2 groups, except that gravidas with cHTN were significantly older than normotensive subjects (mean ± standard deviation [SD] 34 ± 4 vs 30 ± 6 years; P < .001). OSA was more prevalent (64% vs 38%; P = .009; odds ratio [95% confidence interval (CI)] 2.90 [1.30-6.65]; P = .01) and more severe in gravidas with cHTN (moderate or severe OSA 59% vs 21%; P = .009). After controlling for age, we found no overall association between cHTN on OSA risk (adjusted odds ratio [95% CI] 2.22 [0.92-5.40]; P = .076). However, among gravidas older than 25 years of age, cHTN was associated with higher odds of OSA (adjusted odds ratio [95% CI], 2.64 [1.06-6.71], P = .038).

CONCLUSIONS

cHTN and age are important risk factors for OSA in gravidas. Gravidas with cHTN should be screened for OSA in early pregnancy. Future studies may validate screening tools that include cHTN and age, and investigate the role of OSA therapy in blood pressure control.

Impact of Pre-Existing Ischemic Heart Disease on Severe Maternal Morbidity and Mortality During Delivery Hospitalizations

BACKGROUND

The impact of pre-existing ischemic heart disease (IHD) on pregnancy is incompletely described.

OBJECTIVES

The purpose of this study was to compare adverse pregnancy outcomes between those with IHD and those with a cardiac diagnosis categorized by the modified World Health Organization classification and those without a cardiac diagnosis.

METHODS

This retrospective study used the 2015 to 2018 Nationwide Readmissions Database. Delivery hospitalizations, comorbidities, and outcomes were identified using diagnosis and procedure codes. The exposure was isolated IHD. The primary outcome was severe maternal morbidity (SMM) or death during the delivery hospitalization, analyzed using adjusted relative risk (aRR) regression and weighted to account for the Nationwide Readmissions Database's complex survey methods.

RESULTS

Of 11,556,136 delivery hospitalizations, 65,331 had another cardiac diagnosis, and 3,009 had IHD alone. Patients with IHD were older and had higher rates of diabetes and hypertension. In unadjusted analyses, adverse outcomes were more common among patients with IHD alone than among patients with no cardiac disease and modified World Health Organization class I-II disease. After adjustment, patients with IHD alone were associated with a higher risk of SMM or death (aRR: 1.51; 95% CI: 1.19-1.92) than those without a cardiac disease. In comparison, the aRR was 1.90 (95% CI: 1.76-2.06) for WHO class I-II diseases and 5.87 (95% CI: 5.49-6.27) for WHO II/III-IV diseases. Nontransfusion SMM or death (aRR: 1.60; 95% CI: 1.11-2.30) and cardiac SMM or death (aRR: 2.98; 95% CI: 1.75-5.08) were also higher for those with IHD.

CONCLUSIONS

Isolated IHD in pregnancy is associated with worse outcomes than no cardiac disease during delivery hospitalization and approximates the risk associated with WHO I-II diagnoses.

Transfusion Requirements with Hybrid Management of Placenta Accreta Spectrum Incorporating Targeted Embolization and a Selective Use of Delayed Hysterectomy

OBJECTIVE

This study compares the number of units of red blood cells (RBCs) transfused in patients with placenta accreta spectrum (PAS) treated with or without a multidisciplinary algorithm that includes placental uterine arterial embolization (P-UAE) and selective use of either immediate or delayed hysterectomy.

STUDY DESIGN

This is a retrospective study of deliveries conducted at a tertiary care hospital from 2001 to 2018 with pathology-confirmed PAS. Those with previable pregnancies or microinvasive histology were excluded. To improve the equity of comparison, analyses were made separately among scheduled and unscheduled cases, therefore patients were assigned to one of four cohorts as follows: (1) scheduled/per-algorithm, (2) scheduled/off-algorithm, (3) unscheduled/per-algorithm, or (4) unscheduled/off-algorithm. Primary outcomes included RBCs transfused and estimated blood loss (EBL). Secondary outcomes included perioperative complications and disposition.

RESULTS

Overall, 95 patients were identified, with 87 patients meeting inclusion criteria: 36 treated per-algorithm (30 scheduled and 6 unscheduled) and 51 off-algorithm patients (24 scheduled and 27 unscheduled). Among scheduled deliveries, 9 (30.0%) patients treated per-algorithm received RBCs compared with 20 (83.3%) patients treated off-algorithm (p < 0.01), with a median (interquartile range [IQR]) of 3.0 (2.0, 4.0) and 6.0 (2.5, 7.5) units transfused (p = 0.13), respectively. Among unscheduled deliveries, 5 (83.3%) per-algorithm patients were transfused RBCs compared with 25 (92.6%) off-algorithm patients (p = 0.47) with a median (IQR) of 4.0 (2.0, 6.0) and 8.0 (3.0, 10.0) units transfused (p = 0.47), respectively. Perioperative complications were similar between cohorts.

CONCLUSION

A multidisciplinary algorithm including P-UAE and selective use of delayed hysterectomy is associated with a lower rate of blood transfusion in scheduled but not unscheduled cases.

KEY POINTS

· An algorithm with delayed hysterectomy had less transfusion in scheduled, but not unscheduled, cases.. · Over time, more cases were managed per algorithm; among scheduled cases, the transfusion rate and volume transfused decreased.. · There were similar transfusion outcomes among off-algorithm cases, regardless if delivery was scheduled..

Universal Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Testing for Obstetric Inpatient Units Across the United States

BACKGROUND

The purpose of this study was to estimate prevalence of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among patients admitted to obstetric inpatient units throughout the United States as detected by universal screening. We sought to describe the relationship between obstetric inpatient asymptomatic infection rates and publicly available surrounding community infection rates.

METHODS

A cross-sectional study in which medical centers reported rates of positive SARS-CoV-2 testing in asymptomatic pregnant and immediate postpartum patients over a 1-3-month time span in 2020. Publicly reported SARS-CoV-2 case rates from the relevant county and state for each center were collected from the COVID Act Now dashboard and the COVID Tracking Project for correlation analysis.

RESULTS

Data were collected from 9 health centers, encompassing 18 hospitals. Participating health centers were located in Alabama, California, Illinois, Louisiana, New Jersey, North Carolina, Pennsylvania, Rhode Island, Utah, and Washington State. Each hospital had an active policy for universal SARS-CoV-2 testing on obstetric inpatient units. A total of 10 147 SARS-CoV-2 tests were administered, of which 124 were positive (1.2%). Positivity rates varied by site, ranging from 0-3.2%. While SARS-CoV-2 infection rates were lower in asymptomatic obstetric inpatient groups than the surrounding communities, there was a positive correlation between positivity rates in obstetric inpatient units and their surrounding county (P=.003, r=.782) and state (P=.007, r=.708).

CONCLUSIONS

Given the correlation between community and obstetric inpatient rates, the necessity of SARS-CoV-2-related healthcare resource utilization in obstetric inpatient units may be best informed by surrounding community infection rates.

Comparison of severe maternal morbidity in pregnancy by modified World Health Organization Classification of maternal cardiovascular risk

BACKGROUND

To compare rates of severe maternal morbidity (SMM) for pregnant patients with a cardiac diagnosis classified by the modified World Health Organization (mWHO) classification to those without a cardiac diagnosis.

METHODS

This retrospective study using the 2015-2019 Nationwide Readmissions Database identified hospitalizations, comorbidities, and outcomes using diagnosis and procedure codes. The primary exposure was cardiac diagnosis, classified into low-risk (mWHO class I and II) and moderate-to-high-risk (mWHO class II/III, III, or IV). The primary outcome was SMM or death during the delivery hospitalization; secondary outcomes included cardiac-specific SMM during delivery hospitalizations and readmissions after the delivery hospitalization.

RESULTS

A weighted national estimate of 14,995,122 delivery admissions was identified, including 46,541 (0.31%) with mWHO I-II diagnoses and 37,330 (0.25%) with mWHO II/III-IV diagnoses. Patients with mWHO II/III-IV diagnoses experienced SMM at the highest rates (22.8% vs 1.6% for no diagnosis; with adjusted relative risk (aRR) of 5.67 [95% CI: 5.36-6.00]). The risk of death was also highest for patients with mWHO II/III-IV diagnoses (0.3% vs <0.1% for no diagnosis; aRR 18.07 [95% CI: 12.25-26.66]). Elevated risk of SMM and death persisted to 11 months postpartum for those patients with mWHO II/III-IV diagnoses.

CONCLUSIONS

In this nationwide database, SMM is highest among individuals with moderate-to-severe cardiac disease based on mWHO classification. This risk persists in the year postpartum. These results can be used to enhance pregnancy counseling.

Severe Congenital Syphilis in the Neonatal Intensive Care Unit: A Retrospective Case Series

BACKGROUND

There has been a 291% relative increase in congenital syphilis (CS) cases in the United States from 2015 to 2019. Although the majority of affected fetuses/infants are stillborn or are asymptomatic, a subset is born with severe clinical illness. We describe a series of severe CS cases in the neonatal intensive care unit.

METHODS

Retrospective review of infants with CS, admitted to the Duke Intensive Care Nursery from June 2016 to February 2020. We recorded birthweight, gestational age, medications, procedures, diagnoses, laboratory data and outcomes. Severe symptoms included: birth depression, hypoxic ischemic encephalopathy (HIE), disseminated intravascular coagulopathy and/or persistent pulmonary hypertension (PPHN).

RESULTS

Seven infants with CS were identified and 5 with severe presentations were included. Median gestational age was 35.1 weeks (range: 29-37 weeks, median: 35 weeks). All infants required intubation at birth, 2 required chest compressions and epinephrine in the delivery room. One had hydrops fetalis and died in the delivery room. All 4 surviving infants had HIE, severe PPHN, hepatitis and seizures. All infants had a positive rapid plasma reagin, and were treated with penicillin G. Maternal rapid plasma reagin was pending for 3 of 5 infants at delivery, and later returned positive; 2 were positive during pregnancy but not treated. Other infectious work-up was negative. Three infants survived to discharge.

CONCLUSION

CS can be associated with HIE, PPHN and disseminated intravascular coagulopathy in affected infants. Clinicians should have a high index of suspicion and include CS in their differential diagnoses. This study also highlights the importance of adequate treatment of identified cases and screening during the third trimester and at delivery.

Anesthetic management of placenta accreta spectrum at an academic center and a comparison of the combined spinal epidural with the double catheter technique: A retrospective study

STUDY OBJECTIVES

To describe the anesthetic management and outcomes of placenta accreta spectrum (PAS) cases at our institution over a 19 year period and to compare outcomes associated with the lumbar combined spinal epidural (CSE) technique versus the double catheter technique (lumbar CSE with thoracic epidural catheter).

DESIGN

Retrospective cohort study.

SETTING

Labor and delivery unit at a tertiary care center.

PATIENTS

113 female patients who had histologically confirmed PAS on the final pathology report after cesarean delivery or cesarean hysterectomy.

INTERVENTION

Neuraxial anesthesia, including CSE and the double catheter technique, and general anesthesia for PAS cases (including scheduled and unscheduled cases and those known or unknown as PAS preoperatively).

MEASUREMENTS

The medical records were reviewed for demographic information, intraoperative management, anesthetic technique, and outcomes. We describe anesthetic management and outcomes of cases classified as scheduled vs. unscheduled and known vs. unknown PAS. We also compare the CSE and double catheter techniques with the primary outcome being conversion to general anesthesia (GA).

MAIN RESULTS

We included 113 cases: 60 (53.1%) scheduled/known cases, 12 (10.6%), scheduled/unknown cases, 22 (19.5%) unscheduled/known, and 19 (16.8%) unscheduled/unknown cases. All scheduled cases except two were started with a neuraxial technique. General anesthesia (GA) was used to start 18/41 (44%) of unscheduled cases. The double catheter technique (n = 35) was associated with a lower GA conversion rate (5.7% vs. 29.7%, P = 0.036) compared to the CSE technique (n = 37).

CONCLUSIONS

Neuraxial anesthesia is the most commonly used technique for PAS cases in our practice. The double catheter technique was associated with lower GA conversion rates compared to the CSE technique in our cohort.

Placental uterine artery embolization followed by delayed hysterectomy for placenta percreta: A case series

•

Approximately 23% of women intending delayed hysterectomy for placenta accreta spectrum will have an unscheduled surgery.

•

Targeted embolization for placenta accreta spectrum appears to be a safe and feasible adjunct to surgical management.

•

Placental regression may contribute to discrepancy between intraoperative and pathology diagnoses in delayed hysterectomy.

•

A multidisciplinary approach to placenta accreta spectrum is associated with a lower blood loss.

We describe outcomes of patients with suspected placenta percreta treated with placental uterine artery embolization (P-UAE) followed by delayed hysterectomy. This is a prospective case series of subjects from 2005 to 2018 with suspected placenta percreta who underwent P-UAE at the time of cesarean delivery followed by delayed hysterectomy. Both scheduled and unscheduled surgical cases were included. Maternal characteristics, surgical approaches, intra- and postoperative outcomes were abstracted from medical records. In total, twenty-two subjects were included. Median (interquartile range, IQR) delivery gestational age was 34.6 (31.9, 35.7) weeks, occurring as scheduled in 17 (77.3%) subjects and unscheduled in 5 (22.7%). Delayed hysterectomy was performed as scheduled in 17 (77.3%) subjects at a median (IQR) 40.5 (38.0, 44.0) days after delivery, and 5 (22.7%) subjects had a hysterectomy prior to scheduled date, median (IQR) 27.0 (17.0, 35.0) days after delivery. Indications for the 5 unscheduled hysterectomies included bleeding (n = 3) and suspected endometritis (n = 2). Three subjects (13.6%) received a blood transfusion (1, 3, 3 units) during delivery, and 7 (31.8%) were transfused during delayed hysterectomy (median [IQR] 2 [1,3] units). Three (13.6%) subjects had bladder resection at the time of hysterectomy; 1 (4.5%) had an unintentional cystotomy and 1 (4.5%) had a ureteral injury. P-UAE followed by delayed hysterectomy appears to be a safe and feasible, although appropriate patient selection and close surveillance are imperative, as 22.7% of patients underwent unscheduled hysterectomy.

Endocannabinoid System in Pregnancy Maintenance and Labor: A Mini-Review

The endocannabinoid system (ECS) is a cell-signaling system present in multiple organ systems and is an integral part of sustaining the microenvironment necessary for early pregnancy success and maintenance. It plays a significant role in embryo development, transport and implantation as well as placentation. The current theory behind the initiation of term labor is that it is a complex, multifactorial process involving sex steroid hormones, prostaglandin production and interplay at the maternal-fetal interface resulting in increased expression of receptors and gap junctions that promote uterine activation. There is increasing evidence that, in addition to early pregnancy events, the ECS plays a regulatory role in pregnancy maintenance and the timing of labor. This review presents an overview of the ECS in pregnancy that focuses on late gestation and parturition.

Identified themes of interactive visualizations overlayed onto EHR data: an example of improving birth center operating room efficiency

OBJECTIVE

While electronic health record (EHR) systems store copious amounts of patient data, aggregating those data across patients can be challenging. Visual analytic tools that integrate with EHR systems allow clinicians to gain better insight and understanding into clinical care and management. We report on our experience building Tableau-based visualizations and integrating them into our EHR system.

MATERIALS AND METHODS

Visual analytic tools were created as part of 12 clinician-initiated quality improvement projects. We built the visual analytic tools in Tableau and linked it within our EPIC environment. We identified 5 visual themes that spanned the various projects. To illustrate these themes, we choose 1 exemplary project which aimed to improve obstetric operating room efficiency.

RESULTS

Across our 12 projects, we identified 5 visual themes that are integral to project success: scheduling & optimization (in 11/12 projects); provider assessment (10/12); executive assessment (8/12); patient outcomes (7/12); and control and goal charts (2/12).

DISCUSSION

Many visualizations share common themes. Identification of these themes has allowed our internal team to be more efficient and directed in developing visualizations for future projects.

CONCLUSION

Organizing visual analytics into themes can allow informatics teams to more efficiently provide visual products to clinical collaborators.

Prediction of neonatal morbidity and very preterm delivery using maternal steroid biomarkers in early gestation

Background

Preterm delivery is a common pregnancy complication that can result in significant neonatal morbidity and mortality. Limited tools exist to predict preterm birth, and none to predict neonatal morbidity, from early in pregnancy. The objective of this study was to determine if the progesterone metabolites 11-deoxycorticosterone (DOC) and 16-alpha hydroxyprogesterone (16α-OHP), when combined with patient demographic and obstetric history known during the pregnancy, are predictive of preterm delivery-associated neonatal morbidity, neonatal length of stay, and risk for spontaneous preterm delivery prior to 32 weeks’ gestation.

Methods and findings

We conducted a cohort study of pregnant women with plasma samples collected as part of Building Blocks of Pregnancy Biobank at the Indiana University School of Medicine. The progesterone metabolites, DOC and 16α-OHP, were quantified by mass spectroscopy from the plasma of 58 pregnant women collected in the late first trimester/early second trimester. Steroid levels were combined with patient demographic and obstetric history data in multivariable logistic regression models. The primary outcome was composite neonatal morbidity as measured by the Hassan scale. Secondary outcomes included neonatal length of stay and spontaneous preterm delivery prior to 32 weeks’ gestation. The final neonatal morbidity model, which incorporated antenatal corticosteroid exposure and fetal sex, was able to predict high morbidity (Hassan score ≥ 2) with an area under the ROC curve (AUROC) of 0.975 (95% CI 0.932, 1.00), while the model without corticosteroid and fetal sex predictors demonstrated an AUROC of 0.927 (95% CI 0.824, 1.00). The Hassan score was highly correlated with neonatal length of stay (p<0.001), allowing the neonatal morbidity model to also predict increased neonatal length of stay (53 [IQR 22, 76] days vs. 4.5 [2, 31] days, above and below the model cut point, respectively; p = 0.0017). Spontaneous preterm delivery prior to 32 weeks’ gestation was also predicted with an AUROC of 0.94 (95% CI 0.869, 1.00).

Conclusions

Plasma levels of DOC and 16α-OHP in early gestation can be combined with patient demographic and clinical data to predict significant neonatal morbidity, neonatal length of stay, and risk for very preterm delivery, though validation studies are needed to verify these findings. Early identification of pregnancies at risk for preterm delivery and neonatal morbidity allows for timely implementation of multidisciplinary care to improve perinatal outcomes.

Prospective, randomized, double-blind, placebo-controlled evaluation of the Pharmacokinetics, Safety and Efficacy of Recombinant Antithrombin Versus Placebo in Preterm Preeclampsia

BACKGROUND

Despite expectant management, preeclampsia remote from term usually results in preterm delivery. Antithrombin, which displays antiinflammatory and anticoagulant properties, may have a therapeutic role in treating preterm preeclampsia, a disorder characterized by endothelial dysfunction, inflammation, and activation of the coagulation system.

OBJECTIVE

This randomized, placebo-controlled clinical trial aimed to evaluate whether intravenous recombinant human antithrombin could prolong gestation and therefore improve maternal and fetal outcomes.

STUDY DESIGN

We performed a double-blind, placebo-controlled trial at 23 hospitals. Women were eligible if they had a singleton pregnancy, early-onset or superimposed preeclampsia at 23 0/7 to 30 0/7 weeks' gestation, and planned expectant management. In addition to standard therapy, patients were randomized to receive either recombinant human antithrombin 250 mg loading dose followed by a continuous infusion of 2000 mg per 24 hours or an identical saline infusion until delivery. The primary outcome was days gained from randomization until delivery. The secondary outcome was composite neonatal morbidity score. A total of 120 women were randomized.

RESULTS

There was no difference in median gestational age at enrollment (27.3 weeks' gestation for the recombinant human antithrombin group [range, 23.1-30.0] and 27.6 weeks' gestation for the placebo group [range, 23.0-30.0]; P=.67). There were no differences in median increase in days gained (5.0 in the recombinant human antithrombin group [range, 0-75] and 6.0 for the placebo group [range, 0-85]; P=.95). There were no differences between groups in composite neonatal morbidity scores or in maternal complications. No safety issues related to recombinant human antithrombin were noted in this study, despite the achievement of supraphysiological antithrombin concentrations.

CONCLUSION

The administration of recombinant human antithrombin in preterm preeclampsia neither prolonged pregnancy nor improved neonatal or maternal outcomes.

A national update on rates of postpartum haemorrhage and related interventions

BACKGROUND

Postpartum haemorrhage (PPH) is still a leading cause of maternal morbidity in the US. We aimed to reassess national trends in severe and non-severe PPH using recent data.

MATERIAL AND METHODS

We performed a cross-sectional study using the 2001-2012 Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project. Delivery-related hospitalisations with PPH were identified using the International Classification of Diseases (9th revision). Rates were calculated per 1,000 delivery hospitalisations. All statistical analyses accounted for the complex sampling design of the data source.

RESULTS

Rates of non-severe PPH did not change significantly from 2001-2002 to 2011-2012 (25.5 and 24.2 per 1,000; p=0.058). The rates of PPH requiring blood transfusions for caesarean deliveries more than doubled in this time period from 2.0 to 4.8 (p<0.001). The overall rate of PPH with a procedure other than blood transfusion has risen from 0.9 to 1.9. Specifically, rates of hysterectomy (0.5 to 0.7; p<0.001), embolisation (0.3 to 0.5; p<0.001), and uterine tamponade use (0.09 to 0.69; p<0.001) increased over the time period.

DISCUSSION

Population-based surveillance data show an increasing rate of only severe PPH in the US. Rates of medical/surgical intervention including hysterectomy, embolisation and uterine tamponade use are also rising.

Alterations in endogenous progesterone metabolism associated with spontaneous very preterm delivery

STUDY QUESTION

Do maternal serum levels of progesterone metabolites early in pregnancy correspond to an increased risk for very preterm delivery prior to 32 weeks?

SUMMARY ANSWER

Maternal serum levels of 11-deoxycorticosterone (DOC) measured during the late first trimester or early second trimester correlate with an increased risk for preterm delivery prior to 32 weeks, and the correlation becomes stronger when the ratio of DOC to 16-alpha-hydroxyprogesterone was measured.

WHAT IS KNOWN ALREADY

Progesterone is a pro-gestational steroid hormone that has been shown to decrease the risk of preterm birth in some pregnant women. Progesterone is metabolized by the body into various metabolites including members of the mineralocorticoid and glucocorticoid families. Our group has previously demonstrated that some progesterone metabolites enhance myometrial contractility in an ex vivo system, while others result in myometrial relaxation. The current exploratory study was designed to determine if pre-specified metabolites of progesterone measured early in pregnancy were associated with a woman's risk for delivery prior to 32 weeks, which is referred to as a very preterm delivery.

STUDY DESIGN SIZE DURATION

The Building Blocks of Pregnancy Biobank (BBPB) is a biorepository at Indiana University (IU) that follows women prospectively through their pregnancy. A variety of biospecimens are collected at various time points during a woman's pregnancy. Women participating in the IU BBPB who were enrolled after 8 weeks' gestation with pregnancy outcome data were eligible for participation.

PARTICIPANTS/MATERIALS SETTING METHODS

Women delivering prior to 37 weeks (preterm) and at or after 37 weeks (term) who had blood samples collected during the late first trimester/early second trimester and/or during the early third trimester were identified. These samples were then processed for mass spectroscopy, and the amount of progesterone and progesterone metabolites in the samples were measured. Mean values of each measured steroid metabolite were calculated and compared among women delivering at less than 32 weeks, less than 37 weeks and greater than or equal to 37 weeks. Receiver operating characteristic (ROC) curves were constructed and threshold levels determined for each compound to identify a level above or below which best predicted a woman's risk for delivery prior to 32 and prior to 37 weeks. Mann-Whitney U nonparametric testing with Holm-Bonferroni correction for multiple comparisons was utilized to identify steroid ratios that could differentiate women delivering spontaneously at less than 32 weeks from all other pregnancies.

MAIN RESULTS AND THE ROLE OF CHANCE

Steroid hormone levels and pregnancy outcome data were available for 93 women; 28 delivering prior to 32 weeks, 40 delivering between 32 0/7 and 36 6/7 weeks and 25 delivering at or greater than 37 weeks: the mean gestational age at delivery within the three groups was 27.0, 34.4 and 38.8 weeks, respectively. Among women delivering spontaneously at less than 37 weeks, maternal 11-deoxycorticosterone (DOC) levels drawn in the late first trimester/early second trimester were significantly associated with spontaneous preterm delivery prior to 32 weeks; a threshold level of 47.5 pg/ml had 78% sensitivity, 73% specificity and an AUC of 0.77 (P = 0.044). When DOC levels were analyzed as a ratio with other measured steroid hormones, the ratio of DOC to 16-alpha-hydroxyprogesterone among women delivering spontaneously prior to 37 weeks was able to significantly discriminate women delivering prior to 32 weeks from those delivering at or greater than 32 weeks, with a threshold value of 0.2 with 89% sensitivity, 91% specificity and an AUC of 0.92 (P = 0.002). When the entire study cohort population was considered, including women delivering at term and women having an iatrogenic preterm delivery, the ratio of DOC to 16-alpha-hydroxyprogesterone was able to discriminate women delivering spontaneously prior to 32 weeks from the rest of the population at a threshold of 0.18 and 89% sensitivity, 59% specificity and an AUC of 0.81 (P = 0.003).

LIMITATIONS REASONS FOR CAUTION

This is a discovery study, and the findings have not been validated on an independent cohort. To mitigate issues with multiple comparisons, we limited our study to pre-specified metabolites that are most representative of the major metabolic pathways for progesterone, and adjustments for multiple comparisons were made.

WIDER IMPLICATIONS OF THE FINDINGS

Spontaneous preterm birth is increasingly being recognized to represent a common end pathway for a number of different disease phenotypes that include infection, inflammation, premature rupture of the membranes, uterine over distension, cervical insufficiency, placental dysfunction and genetic predisposition. In addition to these phenotypes, longitudinal changes in the maternal-fetal hypothalamic-pituitary-adrenal (HPA) axis also likely contribute to a significant proportion of the disease burden of spontaneous preterm birth. Here, we demonstrate that differential production of steroid metabolites is associated with very early preterm birth. The identified biomarkers may hint at a pathophysiologic mechanism and changes in the maternal-fetal dyad that result in preterm delivery. The early identification of abnormal changes in HPA axis metabolites may allow for targeted interventions that reverse the aberrant steroid metabolic profile to a more favorable one, thereby decreasing the risk for early delivery. Further research is therefore required to validate and extend the results presented here.

STUDY FUNDING/COMPETING INTERESTS

Funding for this study was provided from the Office of the Vice Chancellor for Research at IUPUI, 'Funding Opportunities for Research Commercialization and Economic Success (FORCES) grant'.Both A.S.P. and C.A.G. are affiliated with Nixxi, a biotech startup. The remaining authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

Not applicable.

Are prediction models for vaginal birth after cesarean accurate?

BACKGROUND

The use of trial of labor after cesarean delivery calculators in the prediction of successful vaginal birth after cesarean delivery gives physicians an evidence-based tool to assist with patient counseling and risk stratification. Before deployment of prediction models for routine care at an institutional level, it is recommended to test their performance initially in the institution's target population. This allows the institution to understand not only the overall accuracy of the model for the intended population but also to comprehend where the accuracy of the model is most limited when predicting across the range of predictions (calibration).

OBJECTIVE

The purpose of this study was to compare 3 models that predict successful vaginal birth after cesarean delivery with the use of a single tertiary referral cohort before continuous model deployment in the electronic medical record.

STUDY DESIGN

All cesarean births for failed trial of labor after cesarean delivery and successful vaginal birth after cesarean delivery at an academic health system between May 2013 and March 2016 were reviewed. Women with a history of 1 previous cesarean birth who underwent a trial of labor with a term (≥37 weeks gestation), cephalic, and singleton gestation were included. Women with antepartum intrauterine fetal death or fetal anomalies were excluded. The probability of successful vaginal birth after cesarean delivery was calculated with the use of 3 prediction models: Grobman 2007, Grobman 2009, and Metz 2013 and compared with actual vaginal birth after cesarean delivery success. Each model's performance was measured with the use of concordance indices, Brier scores, and calibration plots. Decision curve analysis identified the range of threshold probabilities for which the best prediction model would be of clinical value.

RESULTS

Four hundred four women met the eligibility criteria. The observed rate of successful vaginal birth after cesarean delivery was 75% (305/404). Concordance indices were 0.717 (95% confidence interval, 0.659-0.778), 0.703 (95% confidence interval, 0.647-0.758), and 0.727 (95% confidence interval, 0.669-0.779), respectively. Brier scores were 0.172, 0.205, and 0.179, respectively. Calibration demonstrated that Grobman 2007 and Metz vaginal birth after cesarean delivery models were most accurate when predicted probabilities were >60% and were beneficial for counseling women who did not desire to have vaginal birth after cesarean delivery but had a predicted success rates of 60-90%. The models underpredicted actual probabilities when predicting success at <60%. The Grobman 2007 and Metz vaginal birth after cesarean delivery models provided greatest net benefit between threshold probabilities of 60-90% but did not provide a net benefit with lower predicted probabilities of success compared with a strategy of recommending vaginal birth after cesarean delivery for all women .

CONCLUSION

When 3 commonly used vaginal birth after cesarean delivery prediction models are compared in the same population, there are differences in performance that may affect an institution's choice of which model to use.

Efficacy of Non-Beta-lactam Antibiotics for Prevention of Cesarean Delivery Surgical Site Infections

Objective  To examine the association between perioperative Beta ( β ))-lactam versus non- β -lactam antibiotics and cesarean delivery surgical site infection (SSI). Study Design  Retrospective cohort of women undergoing cesarean delivery from January 1 to December 31, 2014. All women undergoing cesarean after 34 weeks with a postpartum visit were included. Prevalence of SSI was compared between women receiving β -lactam versus non- β -lactam antibiotics. Bivariate analyses were performed using Pearson's Chi-square, Fisher's exact, or Wilcoxon's rank-sum tests. Logistic regression models were fit controlling for possible confounders. Results  Of the 929 women included, 826 (89%) received β -lactam prophylaxis and 103 (11%) received a non- β -lactam. Among the 893 women who reported a non-type I (low risk) allergy, 819 (92%) received β -lactam prophylaxis. SSI occurred in 7% of women who received β -lactam antibiotics versus 15% of women who received a non- β -lactam ( p  = 0.004). β -Lactam prophylaxis was associated with lower odds of SSI compared with non- β -lactam antibiotics (odds ratio [OR] = 0.43; 95% confidence interval [CI] = 0.22-0.83; p  = 0.01) after controlling for chorioamnionitis in labor, postlabor cesarean, endometritis, tobacco use, and body mass index (BMI). Conclusion   β -Lactam perioperative prophylaxis is associated with lower odds of a cesarean delivery surgical site infection compared with non- β -lactam antibiotics.

Induction of Labor versus Scheduled Cesarean in Morbidly Obese Women: A Cost-Effectiveness Analysis

OBJECTIVE

To assess the costs, complication rates, and harm-benefit tradeoffs of induction of labor (IOL) compared to scheduled cesarean delivery (CD) in women with class III obesity.

STUDY DESIGN

We conducted a cost analysis of IOL versus scheduled CD in nulliparous morbidly obese women. Primary outcomes were surgical site infection (SSI), chorioamnionitis, venous thromboembolism, blood transfusion, and readmission. Model outcomes were mean cost of each strategy, cost per complication avoided, and complication tradeoffs. We assessed the costs, complication rates, and harm-benefit tradeoffs of IOL compared with scheduled CD in women with class III obesity.

RESULTS

A total of 110 patients underwent scheduled CD and 114 underwent IOL, of whom 61 (54%) delivered via cesarean. The group delivering vaginally experienced fewer complications. SSI occurred in 0% in the vaginal delivery group, 13% following scheduled cesarean, and 16% following induction then cesarean. In the decision model, the mean cost of induction was $13,349 compared with $14,575 for scheduled CD. Scheduled CD costs $9,699 per case of chorioamnionitis avoided, resulted in 18 cases of chorioamnionitis avoided per additional SSI and 3 cases of chorioamnionitis avoided per additional hospital readmission. In sensitivity analysis, IOL is cost saving compared with scheduled CD unless the cesarean rate following induction exceeds 70%.

CONCLUSION

In morbidly obese women, induction of labor remains cost-saving until the rate of cesarean following induction exceeds 70%.

Effect of Cord Blood Magnesium Level at Birth on Non-neurologic Neonatal Outcomes

OBJECTIVE

We examined the effects of magnesium sulfate on non-neurologic neonatal outcomes with respect to cord blood magnesium level.

STUDY DESIGN

We conducted a secondary analysis of the Maternal-Fetal Medicine Units Beneficial Effects of Antenatal Magnesium (MFMU BEAM) trial comparing the upper and lower quintiles of cord blood magnesium level. Outcomes included cerebral palsy (CP), necrotizing enterocolitis (NEC), retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), and assessments of mental and motor disability. Logistic regression was used to estimate adjusted odds ratios (aORs) of each outcome, controlling for gestational age (GA), birth weight, and treatment group (TG).

RESULTS

A total of 1,254 women of the 2,444 included in the BEAM trial had cord blood magnesium levels recorded. GA and birth weight were lower and TG was more common in the upper quintile cohort (p < 0.001). Neonates in the upper quintile were more likely to have severe NEC (OR, 2.41, 95% confidence interval [CI]: 1.11-5.24), ROP (OR, 1.65, 95% CI: 1.05-2.59), and BPD (OR, 1.70, 95% CI: 1.04-2.73). Adjustment for covariates demonstrated no difference in the NEC, ROP, and BPD rates, although there was a decrease in rates of mental disability index < 70 which was not seen in the unadjusted analysis (aOR, 0.49, 95% CI: 0.25-0.99).

CONCLUSION

Higher cord blood magnesium levels do not appear to have adverse non-neurologic effects on the neonate and may demonstrate improvement in neurologic outcomes.

β-arrestin 1 regulates β2-adrenergic receptor-mediated skeletal muscle hypertrophy and contractility

BACKGROUND

β₂-adrenergic receptors (β₂ARs) are the target of catecholamines and play fundamental roles in cardiovascular, pulmonary, and skeletal muscle physiology. An important action of β₂AR stimulation on skeletal muscle is anabolic growth, which has led to the use of agonists such as clenbuterol by athletes to enhance muscle performance. While previous work has demonstrated that β₂ARs can engage distinct signaling and functional cascades mediated by either G proteins or the multifunctional adaptor protein, β-arrestin, the precise role of β-arrestin in skeletal muscle physiology is not known. Here, we tested the hypothesis that agonist activation of the β₂AR by clenbuterol would engage β-arrestin as a key transducer of anabolic skeletal muscle growth.

METHODS

The contractile force of isolated extensor digitorum longus muscle (EDL) and calcium signaling in isolated flexor digitorum brevis (FDB) fibers were examined from the wild-type (WT) and β-arrestin 1 knockout mice (βarr1KO) followed by chronic administration of clenbuterol (1 mg/kg/d). Hypertrophic responses including fiber composition and fiber size were examined by immunohistochemical imaging. We performed a targeted phosphoproteomic analysis on clenbuterol stimulated primary cultured myoblasts from WT and βarr1KO mice. Statistical significance was determined by using a two-way analysis with Sidak's or Tukey's multiple comparison test and the Student's t test.

RESULTS

Chronic administration of clenbuterol to WT mice enhanced the contractile force of EDL muscle and calcium signaling in isolated FDB fibers. In contrast, when administered to βarr1KO mice, the effect of clenbuterol on contractile force and calcium influx was blunted. While clenbuterol-induced hypertrophic responses were observed in WT mice, this response was abrogated in mice lacking β-arrestin 1. In primary cultured myoblasts, clenbuterol-stimulated phosphorylation of multiple pro-hypertrophy proteins required the presence of β-arrestin 1.

CONCLUSIONS

We have identified a previously unappreciated role for β-arrestin 1 in mediating β₂AR-stimulated skeletal muscle growth and strength. We propose these findings could have important implications in the design of future pharmacologic agents aimed at reversing pathological conditions associated with skeletal muscle wasting.

Neonatal Outcomes Associated with Noncephalic Presentation at Delivery in Preterm Birth

OBJECTIVE

The objective of this study is to evaluate the effect of noncephalic presentation on neonatal outcomes in preterm delivery.

STUDY DESIGN

In this study a secondary analysis of the BEAM trial was performed. It included women with singleton, liveborn, and nonanomalous fetuses. Neonatal outcomes were compared in noncephalic versus cephalic presentation. Adjusted odds ratios and 95% confidence intervals were calculated for each outcome with logistic regression while controlling for possible confounders. A stratified analysis by mode of delivery was also performed in this study.

RESULTS

A total of 458 noncephalic deliveries were compared with 1,485 cephalic deliveries. In multivariate analysis, noncephalic presentation was associated with increased risk of death in the neonatal intensive care unit (NICU) or death at <15 months corrected gestational age (cGA), and a decreased risk of IVH. The risk of death persisted in stratified analysis, with increased risk of death at <15 months cGA in noncephalic neonates born via cesarean delivery. In the vaginal delivery group, there was an increased risk of death at <15 months cGA and NICU death.

CONCLUSION

After controlling for possible confounders, neonates who are noncephalic at delivery have higher risk for death <15 months cGA and death in the NICU while their risk of IVH is reduced. The risk of death persisted in stratified analyses by mode of delivery.

Can we improve the gestation-adjusted projection (GAP) method for prediction of birth weight in morbidly obese women?. J Matern Fetal Neonatal Med 2018;32:3600-3605. [PMID: 29681190 DOI: 10.1080/14767058.2018.1468882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Objective: The gestation-adjusted projection (GAP) is a method to predict birthweight using population birth data and third trimester ultrasound fetal weight. This method usually utilizes population birth weight data from almost 40 years ago. In 2011, a large cohort of racially diverse infants across the US was included to validate updated birth curves. Our objective was to determine if the updated data would improve the accuracy of the GAP method during the third trimester among obese women. Methods: This secondary analysis of a cohort study included singleton pregnancies of obese women who had fetal growth assessment(s) in the third trimester. The first subgroup (N = 235) included women with a BMI >40 kg/m² who had ultrasounds during 30 + 0-35 + 0 weeks (EARLY) and greater than 35 + 0 weeks (LATE). The second subgroup (N = 431) included women with a BMI 30-35, 40-50, or >50 kg/m² who had an ultrasound during 34 + 0-36 + 6 weeks. Mean absolute percent error was calculated for all GAP methods and compared using paired t-tests. Sensitivity, specificity, and area under the curve for diagnosis of birth weight >4000 grams were also estimated for each GAP method. Results: The mean absolute percent error for the first subgroup (N = 235) using historical population birth weights was 7.4-7.9%. After using updated population birth weight curves using all neonates, the mean absolute percent error for the first subgroup ranged between 7.6 and 9.4%. GAP predictions using all neonates, as well as male and female-specific birth data compared to the historical population data during both the EARLY and LATE periods were significantly worse (p < .01). The mean absolute percent error for the second subgroup (N = 431) using historical population birth weights ranged from 7.2 to 7.9%. The absolute percent error using gender-specific compared to historical data was significant in the BMI 30-35 group (male 8.1% versus historical 7.6%, p < .01, female 8.1% versus historical 7.6%, p < .01). The differences in absolute percent error between historical and updated population data became less evident in the BMI 40-50 and >50-kg/m² groups (p = .05 and p = .15, respectively) though still overall performed worse with the updated data. Conclusions: Prediction of birth weight using the GAP method does not seem to be improved among obese women after using updated population data. Alternatively, modeling techniques may need to be applied to improve the accuracy of the GAP method.

The Oxytocin Product Correlates with Total Oxytocin Received during Labor: A Research Methods Study

OBJECTIVE

Total dose of oxytocin received during labor is an important variable in studies of human labor but is difficult to calculate. We sought to identify a surrogate measure for total dose of oxytocin received.

STUDY DESIGN

For each subject receiving oxytocin during labor, the oxytocin total dose received in labor was calculated as the area under the curve. Maximal oxytocin infusion rate, total duration of oxytocin infusion, and the product of both, defined as the oxytocin product, were then each correlated with the total dose of oxytocin received using the Pearson's correlation coefficient.

RESULTS

Oxytocin dosing data were available from 402 women at Duke and 6,907 women from Pithagore6. The two variables alone, or combined as the oxytocin product, demonstrated a high correlation with the oxytocin total dose (r > 0.7), with the oxytocin product demonstrating the highest (r > 0.9). This was true whether labor was induced or augmented and whether delivery was vaginal or cesarean.

CONCLUSION

The oxytocin product, composed of two easily obtained variables, demonstrated a very high correlation with total oxytocin dose received in labor and represents a simple and accurate surrogate for total dose of oxytocin received during labor. The oxytocin product can be used in clinical studies in which oxytocin dose is an important variable.

The association of single-nucleotide polymorphisms in the oxytocin receptor and G protein-coupled receptor kinase 6 (GRK6) genes with oxytocin dosing requirements and labor outcomes

BACKGROUND

Oxytocin is a potent uterotonic agent that is widely used for induction and augmentation of labor. Oxytocin has a narrow therapeutic index and the optimal dosing for any individual woman varies widely.

OBJECTIVE

The objective of this study was to determine whether genetic variation in the oxytocin receptor (OXTR) or in the gene encoding G protein-coupled receptor kinase 6 (GRK6), which regulates desensitization of the oxytocin receptor, could explain variation in oxytocin dosing and labor outcomes among women being induced near term.

STUDY DESIGN

Pregnant women with a singleton gestation residing in Durham County, NC, were prospectively enrolled as part of the Healthy Pregnancy, Healthy Baby cohort study. Those women undergoing an induction of labor at 36 weeks or greater were genotyped for 18 haplotype-tagging single-nucleotide polymorphisms in OXTR and 7 haplotype-tagging single-nucleotide polymorphisms in GRK6 using TaqMan assays. Linear regression was used to examine the relationship between maternal genotype and maximal oxytocin infusion rate, total oxytocin dose received, and duration of labor. Logistic regression was used to test for the association of maternal genotype with mode of delivery. For each outcome, backward selection techniques were utilized to control for important confounding variables and additive genetic models were used. Race/ethnicity was included in all models because of differences in allele frequencies across populations, and Bonferroni correction for multiple testing was used.

RESULTS

DNA was available from 482 women undergoing induction of labor at 36 weeks or greater. Eighteen haplotype-tagging single-nucleotide polymorphisms within OXTR and 7 haplotype-tagging single-nucleotide polymorphisms within GRK6 were examined. Five single-nucleotide polymorphisms in OXTR showed nominal significance with maximal infusion rate of oxytocin, and two single-nucleotide polymorphisms in OXTR were associated with total oxytocin dose received. One single-nucleotide polymorphism in OXTR and two single-nucleotide polymorphisms in GRK6 were associated with duration of labor, one of which met the multiple testing threshold (P = .0014, rs2731664 [GRK6], mean duration of labor, 17.7 hours vs 20.2 hours vs 23.5 hours for AA, AC, and CC genotypes, respectively). Three single-nucleotide polymorphisms, two in OXTR and one in GRK6, showed nominal significance with mode of delivery.

CONCLUSION

Genetic variation in OXTR and GRK6 is associated with the amount of oxytocin required as well as the duration of labor and risk for cesarean delivery among women undergoing induction of labor near term. With further research, pharmacogenomic approaches may potentially be utilized to develop personalized treatment to improve safety and efficacy outcomes among women undergoing induction of labor.

Using antifibrinolytics in the peripartum period - concern for a hypercoagulable effect?

INTRODUCTION

Although antifibrinolytic agents are used to prevent and treat hemorrhage, there are concerns about a potential increased risk for peripartum venous thromboembolism. We sought to determine the impact of tranexamic acid and ɛ-aminocaproic acid on in vitro clotting properties in pregnancy.

METHODS

Blood samples were obtained from healthy pregnant, obese, and preeclamptic pregnant women (n = 10 in each group) prior to delivery as well as from healthy non-pregnant controls (n = 10). Maximum clot firmness (MCF) and clotting time (CT) were measured using rotation thromboelastometry in the presence of tranexamic acid (3, 30, or 300 μg/mL) or ɛ-aminocaproic acid (30, 300, or 3000 μg/mL). ANOVA and regression analyses were performed.

RESULTS

Mean whole blood MCF was significantly higher in healthy pregnant vs. non-pregnant women (66.5 vs. 57.5 mm, p < 0.001). Among healthy pregnant women, there was no significant difference between mean MCF (whole blood alone, and with increasing tranexamic acid doses = 66.5, 66.1, 66.4, 66.3 mm, respectively; p = 0.25) or mean CT (409, 412, 420, 424 sec; p = 0.30) after addition of tranexamic acid. Similar results were found using ɛ-aminocaproic acid. Preeclamptic women had a higher mean MCF after the addition of ɛ-aminocaproic acid and tranexamic acid (p = 0.05 and p = 0.04, respectively) compared to whole blood alone.

CONCLUSIONS

Pregnancy is a hypercoagulable state, as reflected by an increased MCF compared to non-pregnant women. Addition of antifibrinolytic therapy in vitro does not appear to increase MCF or CT for non-pregnant, pregnant, and obese women. Whether antifibrinolytics are safe in preeclampsia may require further study.

Prevention of preeclampsia

Preeclampsia is a common complication of pregnancy that is associated with an increased risk of maternal and neonatal morbidity and mortality. Currently, delivery is the only cure for preeclampsia; therefore, effective prevention and treatment options for this condition are sorely needed. In the current issue of the JCI, Mirzakhani et al. report the findings of the Vitamin D Antenatal Asthma Reduction Trial (VDAART), a well-conducted large, randomized, double-blind, placebo-controlled trial of vitamin D supplementation for the prevention of preeclampsia. Though vitamin D supplementation had no effect on the risk of preeclampsia, reduced maternal serum vitamin D levels did correlate with preeclampsia risk. Mirzakhani and colleagues identified a number of gene pathways that are differentially regulated among women with low serum vitamin D levels who develop preeclampsia. These results indicate that further research on the role of vitamin D in preeclampsia is warranted.

Thrombin-Induced Inflammation in Human Decidual Cells Is Not Affected By Heparin

OBJECTIVE

Thrombin (Thr) generation at the uteroplacental interface induces inflammation and weakens fetal membranes. Tissue factor (TF) is a powerful procoagulant that is increased by Thr in decidual cells (DCs). The TF expression may play an important role in modulating Thr-induced inflammation. The purpose of this study was to assess the effect of heparin, including nonanticoagulant (desulfated) heparins, on basal and Thr-induced expression of TF and inflammatory cytokines in DCs.

METHODS

Fetal membranes were collected from term pregnancies undergoing unlabored cesarean delivery and then DCs were isolated and cultured. Third passage DCs were conditioned in defined media for 1 week and then treated with 1 of the 4 heparins (enoxaparin, unfractionated heparin, and 2 desulfated heparins) with and without Thr (2.5 U/mL) for 24 hours. Supernatant levels of interleukin (IL) 6, IL-8, IL-10, tumor necrosis factor α, and interferon γ (IFN-γ) were determined by enzyme-linked immunosorbent assay. Western blots were performed on cell lysates to determine TF expression. A Kruskal-Wallis test was used to compare cytokine concentrations and normalized TF expression among treatments.

RESULTS

Treatment of DCs with Thr alone increased the expression of TF, IL-6, IL8, IL-10, and IFN-γ compared to basal levels ( P < .05 for each). Cotreatment of DCs with Thr and any of the tested heparins did not decrease the expression of TF or inflammatory cytokines compared to treatment with Thr alone.

DISCUSSION

Heparins do not appear to affect basal or Thr-induced expression of TF or inflammatory cytokines in human term DCs. Additional work is needed to determine whether nonanticoagulant heparins can reduce inflammation and membrane weakening due to bleeding in pregnancy.

Cesarean delivery among women with prolonged labor induction

OBJECTIVE

The objective of this study was to determine characteristics associated with cesarean delivery among women with labor induction lasting over 24 h.

STUDY DESIGN

Women with live singleton pregnancies without prior cesarean delivery undergoing a labor induction lasting >24 h between September 2006 and March 2009 at Duke University Hospital were identified. Collected variables were compared between subjects by mode of delivery. A multivariate logistic regression model for the outcome cesarean delivery was constructed separately for nulliparous and parous women.

RESULTS

There were 303 women who met inclusion criteria. The overall cesarean delivery rate was 57% (n=172) and remained constant with time (P=0.15, test-for-trend). Nulliparous women having a cesarean delivery were more likely to be obese [adjusted OR (aOR) 2.00; 95% CI 1.05, 3.80] and have a larger fetus [aOR 1.11 (aOR for every 100 g increase in birthweight), 95% CI 1.03, 1.20] compared to those having a vaginal delivery.

CONCLUSION

Increasing BMI and birthweight were independent predictors of cesarean delivery among nulliparous women with prolonged labor induction. Despite this, after 24 h of labor induction, the overall mean cesarean delivery rate remained constant at 57%, and did not change with time. Among women having a vaginal delivery following a prolonged labor induction, we saw high rates of shoulder dystocia, operative vaginal delivery and severe perineal laceration.

Comparison of the Trends in Risk Factors and Management of Severe Postpartum Hemorrhage Years 2000-2004 Versus 2005-2008

OBJECTIVE

To compare trends in the etiology and management of severe postpartum hemorrhage (PPH) during 2 time periods: 2000-2004 (Period 1) versus 2005-2008 (Period 2).

STUDY DESIGN

Medical records with a diagnosis of PPH were identified by ICD-9 codes for immediate, third-stage, delayed, and secondary. PPH and post- partum coagulation defect. Subjects having a PPH within 24 hours of delivery who also received blood component therapy (defined as severe PPH) during Period 1 were compared with those from Period 2.

RESULTS

There were 109 and 119 cases identified from Periods 1 and 2, respectively. Uterine atony was the most common cause of severe PPH during both time periods. In the second time period women with severe PPH had a lower mean hematocrit (p<0.05), a greater mean BMI (p<0.05), and more induced labor (p<0.01) as compared to the first time period. A greater proportion of the women in the second time period received misoprostol (p<0.0001) and platelets (p<0.05). The proportions of other therapies and surgical interventions remained unchanged, as did the ultimate outcomes.

CONCLUSION

At a single large institution over the course of a 9-year period the management of severe PPH changed to include a greater utilization of misoprostol and platelet therapy.

Maternal Effects of Respiratory Syncytial Virus Infection during Pregnancy

Clarifying these effects could show potential benefits of RSV vaccination of pregnant women.

Given the illness and deaths caused by respiratory syncytial virus (RSV) infection during the first year of life, preventing infant RSV infections through maternal vaccination is intriguing. However, little is known about the extent and maternal effects of RSV infection during pregnancy. We describe 3 cases of maternal RSV infection diagnosed at a US center during winter 2014. Case-patient 1 (26 years old, week 33 of gestation) received a diagnosis of RSV infection and required mechanical ventilation. Case-patient 2 (27 years old, week 34 of gestation) received a diagnosis of infection with influenza A(H1N1) virus and RSV and required mechanical ventilation. Case-patient 3 (21 years old, week 32 of gestation) received a diagnosis of group A streptococcus pharyngitis and RSV infection and was monitored as an outpatient. Clarifying the effects of maternal RSV infection could yield valuable insights into potential maternal and fetal benefits of an effective RSV vaccination program.

Enhanced Uterine Contractility and Stillbirth in Mice Lacking G Protein-Coupled Receptor Kinase 6 (GRK6): Implications for Oxytocin Receptor Desensitization

Oxytocin is a potent uterotonic agent and is used clinically for induction and augmentation of labor, as well as for prevention and treatment of postpartum hemorrhage. Oxytocin increases uterine contractility by activating the oxytocin receptor (OXTR), a member of the G protein-coupled receptor family, which is prone to molecular desensitization. After oxytocin binding, the OXTR is phosphorylated by a member of the G protein-coupled receptor kinase (GRK) family, which allows for recruitment of β-arrestin, receptor internalization, and desensitization. According to previous in vitro analyses, desensitization of calcium signaling by the OXTR is mediated by GRK6. The objective of this study was to determine the role of GRK6 in mediating uterine contractility. Here, we demonstrate that uterine GRK6 levels increase in pregnancy and using a telemetry device to measure changes in uterine contractility in live mice during labor, show that mice lacking GRK6 produce a phenotype of enhanced uterine contractility during both spontaneous and oxytocin-induced labor compared with wild-type or GRK5 knockout mice. In addition, the observed enhanced contractility was associated with high rates of term stillbirth. Lastly, using a heterologous in vitro model, we show that β-arrestin recruitment to the OXTR, which is necessary for homologous OXTR desensitization, is dependent on GRK6. Our findings suggest that GRK6-mediated OXTR desensitization in labor is necessary for normal uterine contractile patterns and optimal fetal outcome.

Increase in Cesarean Operative Time Following Institution of the 80-Hour Workweek

BACKGROUND

In 2003, the Accreditation Council for Graduate Medical Education limited resident duty hours to 80 hours per week. More than a decade later, the effect of the limits on resident clinical competence is not fully understood.

OBJECTIVE

We sought to assess the effect of duty hour restrictions on resident performance of an uncomplicated cesarean delivery.

METHODS

We reviewed unlabored primary cesarean deliveries at Duke University Hospital after 34 weeks gestation, between 2003 and 2011. Descriptive statistics and linear regression were used to compare total operative time with incision to delivery time as a function of years since institution of the 80-hour workweek. Resident training level, subject body mass index, estimated blood loss, and skin closure method were controlled for in the regression model.

RESULTS

We identified 444 deliveries that met study criteria. The mean (SD) total operative time in 2003-2004 was 43.3 (14.3) minutes and 59.6 (10.7) minutes in 2010-2011 (P < .001). Multivariable regression demonstrated an increase in total operative time of 1.9 min/y (P < .001) but no change in incision to delivery time (P = .05). The magnitude of increased operative time was seen among junior residents (2.0 min/y, P < .001) compared to that of senior residents (1.2 min/y, P = .06).

CONCLUSIONS

Since introduction of the 2003 duty hour limits, there has been an increase of nearly 20 minutes in the time required for a routine cesarean delivery. It is unclear if the findings are due to a change in residency duty hours or to another aspect of residency training.

Medical and Obstetric Outcomes Among Pregnant Women With Congenital Heart Disease

OBJECTIVE

To estimate nationwide trends in the prevalence of maternal congenital heart disease (CHD) and determine whether women with CHD are more likely than women without maternal CHD to have medical and obstetric complications.

METHODS

The 2000-2010 Nationwide Inpatient Sample was queried for International Classification of Diseases, 9th Revision, Clinical Modification codes to identify delivery hospitalizations of women with and without CHD. Trends in the prevalence of CHD were determined and then rates of complications were reported for CHD per 10,000 delivery hospitalizations. For Nationwide Inpatient Sample 2008-2010, logistic regression was used to examine associations between CHD and complications.

RESULTS

From 2000 to 2010, there was a significant linear increase in the prevalence of CHD from 6.4 to 9.0 per 10,000 delivery hospitalizations (P<.001). Multivariable logistic regression demonstrated that all selected medical complications, including mortality (17.8 compared with 0.7/10,000 deliveries, adjusted odds ratio [OR] 22.10, 95% confidence interval [CI] 13.96-34.97), mechanical ventilation (91.9 compared with 6.9/10,000, adjusted OR 9.94, 95% CI 7.99-12.37), and a composite cardiovascular outcome (614 compared with 34.3/10,000, adjusted OR 10.54, 95% CI 9.55-11.64) were more likely to occur among delivery hospitalizations with maternal CHD than without. Obstetric complications were also common among women with CHD. Delivery hospitalizations with maternal CHD that also included codes for pulmonary circulatory disorders had higher rates of medical complications compared with hospitalizations with maternal CHD without pulmonary circulatory disorders.

CONCLUSION

The number of delivery hospitalizations with maternal CHD in the United States is increasing, and although we were not able to determine whether correction of the cardiac lesion affected outcomes, these hospitalizations have a high burden of medical and obstetric complications.

LEVEL OF EVIDENCE

II.

Progesterone Metabolites Produced by Cytochrome P450 3A Modulate Uterine Contractility in a Murine Model

OBJECTIVE

We seek to characterize the effect of progesterone metabolites on spontaneous and oxytocin-induced uterine contractility.

STUDY DESIGN

Spontaneous contractility was studied in mouse uterine horns after treatment with progesterone, 2α-hydroxyprogesterone, 6β-hydroxyprogesterone (6β-OHP), 16α-hydroxyprogesterone (16α-OHP), or 17-hydroxyprogesterone caproate (17-OHPC) at 10(-9) to 10(-6) mol/L. Uterine horns were exposed to progestins (10(-6) mol/L), followed by increasing concentrations of oxytocin (1-100 nmol/L) to study oxytocin-induced contractility. Contraction parameters were compared for each progestin and matched vehicle control using repeated measures 2-way analysis of variance. In vitro metabolism of progesterone by recombinant cytochrome P450 3A (CYP3A) microsomes (3A5, 3A5, and 3A7) identified major metabolites.

RESULTS

Oxytocin-induced contractile frequency was decreased by 16α-OHP (P = .03) and increased by 6β-OHP (P = .05). Progesterone and 17-OHPC decreased oxytocin-induced contractile force (P = .02 and P = .04, respectively) and frequency (P = .02 and P = .03, respectively). Only progesterone decreased spontaneous contractile force (P = .02). Production of 16α-OHP and 6β-OHP metabolites were confirmed in all CYP3A isoforms tested.

CONCLUSION

Progesterone metabolites produced by maternal or fetal CYP3A enzymes influence uterine contractility.

The Effect of Progestins on Tumor Necrosis Factor α-Induced Matrix Metalloproteinase-9 Activity and Gene Expression in Human Primary Amnion and Chorion Cells In Vitro

BACKGROUND

Current treatment modalities for preventing preterm premature rupture of membranes are limited, but progestins may play a role. Tumor necrosis factor α (TNFα) enhances matrix metalloproteinase-9 (MMP-9) gene expression and activity in fetal membranes, contributing to membrane weakening and rupture. We previously demonstrated that progestins attenuate TNFα-induced MMP-9 activity in a cytotrophoblast cell line. However, whether they have a similar effect in primary amnion and chorion cells of fetal membranes is unknown. In this study, we evaluated the effect of progestins on basal and TNFα-induced MMP-9 activity and gene expression in primary chorion and amnion cells harvested from the fetal membranes of term nonlaboring patients.

METHODS

Primary amnion and chorion cells were isolated from fetal membranes obtained from term uncomplicated nonlaboring patients following elective cesarean delivery (n = 11). Confluent primary amnion and chorion cell cultures were both pretreated with vehicle (control), progesterone (P4), 17α-hydroxyprogesterone caproate (17P), or medroxyprogesterone acetate (MPA) at 10 M concentration for 6 hours followed by stimulation with TNFα at 10 ng/mL for an additional 24 hours. Cell cultures pretreated with the vehicle only served as the unstimulated control and the vehicle stimulated with TNFα served as the stimulated control. Both controls were assigned a value of 100 units. Cell culture medium was harvested for MMP-9 enzymatic activity quantification using gelatin zymography. Total RNA was extracted for quantifying MMP-9 gene expression using real-time quantitative PCR. Basal MMP-9 activity and gene expression data were normalized to the unstimulated control. TNFα-stimulated MMP-9 activity and gene expression were normalized to the stimulated control. The primary outcome was the effect of progestins on TNFα-induced MMP-9 enzymatic activity in term human primary amnion and chorion cells in vitro. Secondary outcomes included the effect of progestin therapy on TNFα-induced MMP-9 gene expression and on basal MMP-9 activity and gene expression in primary amnion and chorion cells in vitro.

RESULTS

Primary cells were harvested from 11 patients. Compared with the unstimulated control, TNFα increased MMP-9 activity (P = 0.005 versus control in primary amnion cells and P < 0.001 versus control in primary chorion cells) and MMP-9 gene expression (P = 0.030 versus control in primary amnion cells, P < 0.001 versus control in primary chorion cells). Compared with the unstimulated controls, MPA, but not P4 or 17P, reduced basal MMP-9 activity [mean difference (95% CI) -49.6 (-81.9, -17.3) units, P = 0.001] and gene expression [mean difference (95% CI) -53.4 (-105.9, -0.9) units, P = 0.045] in primary amnion cells. Compared with the stimulated control, MPA also reduced TNFα-induced MMP-9 activity [mean difference (95% CI) -69.0 (-91.8, -46.3) units, P < 0.001] and gene expression [mean difference (95% CI) -86.0 (-120.7, -51.3) units, P < 0.001] in primary amnion cells. Progestin pretreatment had no significant effect on basal or TNFα-induced MMP-9 activity and gene expression in primary chorion cells.

CONCLUSIONS

The inhibitory effect of MPA on both basal and TNFα-induced MMP-9 activity and gene expression in primary amnion cells demonstrate a possible mechanism by which progestins may prevent fetal membrane weakening leading to preterm premature rupture of membranes.

Intrauterine telemetry to measure mouse contractile pressure in vivo

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. Despite the discovery of key regulators of uterine contractility, this process is still not fully understood. Transgenic mice provide an ideal model in which to study parturition. Previously, the only method to study uterine contractility in the mouse was ex vivo isometric tension recordings, which are suboptimal for several reasons. The uterus must be removed from its physiological environment, a limited time course of investigation is possible, and the mice must be sacrificed. The recent development of radiometric telemetry has allowed for longitudinal, real-time measurements of in vivo intrauterine pressure in mice. Here, the implantation of an intrauterine telemeter to measure pressure changes in the mouse uterus from mid-pregnancy until delivery is described. By comparing differences in pressures between wild type and transgenic mice, the physiological impact of a gene of interest can be elucidated. This technique should expedite the development of therapeutics used to treat myometrial disorders during pregnancy, including preterm labor.

Medical and obstetric complications among pregnant women with cystic fibrosis

OBJECTIVE

The objective of this study was to estimate the nationwide prevalence of cystic fibrosis (CF) in pregnancy and determine what medical complications exist at delivery among pregnant women with CF.

STUDY DESIGN

The Nationwide Inpatient Sample (NIS) was queried for all delivery-related discharges. Women with CF were identified by International Classification of Diseases, 9th revision, Clinical Modifications codes and compared with women without CF. The prevalence of selected severe medical complications was compared between the 2 groups (NIS years 2008-2010) using multivariable logistic regression and the linear change in prevalence of CF at delivery determined (NIS years 2000-2010).

RESULTS

From 2000 to 2010, there was a significant linear increase in the prevalence of CF at delivery from 3.0 to 9.8 per 100,000 deliveries, in 2000 and 2010, respectively (R(2) = 0.92, P < .0001). From 2008-2010, there were 1119 deliveries to women with CF and 12,627,627 to women without CF. Women with CF were more likely to be white (P < .0001) and have diabetes (odds ratio [OR], 14.0; 95% confidence interval [CI], 11.8-16.7) or asthma (OR, 5.1; 95% CI, 4.3-6.1). Multivariable logistic regression demonstrated that women with CF were more likely to die (adjusted OR [aOR], 76.0; 95% CI, 31.6-183), require mechanical ventilation (aOR, 18.3; 95% CI, 10.8-31.2), or have pneumonia (aOR, 56.5; 95% CI, 43.2-74.1), acute renal failure (aOR, 17.3; 95% CI, 9.1-32.6), preterm labor (aOR, 2.2; 95% CI, 1.9-2.6), or an adverse composite CF outcome (aOR, 28.1; 95% CI, 21.8-36.3).

CONCLUSION

Pregnant women with CF are more likely to die, require mechanical ventilation, and have infectious complications compared with women without CF, although the absolute risks are low and these events are relatively rare.