Postpartum pharmacologic thromboprophylaxis and complications in a US cohort

BACKGROUND

Venous thromboembolism accounts for approximately 9% of pregnancy-related deaths in the United States. National guidelines recommend postpartum risk stratification and pharmacologic prophylaxis in at-risk individuals. Knowledge on modern rates of postpartum pharmacologic thromboprophylaxis and its associated risks is limited.

OBJECTIVE

This study aimed to describe the rate of, and factors associated with, initiation of postpartum pharmacologic prophylaxis for venous thromboembolism, and to assess associated adverse outcomes.

STUDY DESIGN

This was a secondary analysis of a multicenter cohort of individuals delivering on randomly selected days at 17 US hospitals (2019-2020). Medical records were reviewed by trained and certified personnel. Those with an antepartum diagnosis of venous thromboembolism, receiving antepartum anticoagulation, or known SARS-CoV-2 infection were excluded. The primary outcome was use of postpartum pharmacologic thromboprophylaxis. Secondary outcomes included bleeding complications, surgical site infection, hospital readmission, and venous thromboembolism through 6 weeks postpartum. The rate of thromboprophylaxis administration was assessed by mode of delivery, institution, and continuance to the outpatient setting. Multivariable regression models were developed using k-fold cross-validation with stepwise backward elimination to evaluate factors associated with thromboprophylaxis administration. Univariable and multivariable logistic models with propensity score covariate adjustment were performed to assess the association between thromboprophylaxis administration and adverse outcomes.

RESULTS

Of 21,114 individuals in the analytical cohort, 11.9% (95% confidence interval, 11.4%-12.3%) received postpartum pharmacologic thromboprophylaxis; the frequency of receipt was 29.8% (95% confidence interval, 28.7%-30.9%) following cesarean and 3.5% (95% confidence interval, 3.2%-3.8%) following vaginal delivery. Institutional rates of prophylaxis varied from 0.21% to 34.8%. Most individuals (83.3%) received thromboprophylaxis only as inpatients. In adjusted analysis, cesarean delivery (adjusted odds ratio, 19.17; 95% confidence interval, 16.70-22.00), hysterectomy (adjusted odds ratio, 15.70; 95% confidence interval, 4.35-56.65), and obesity (adjusted odds ratio, 3.45; 95% confidence interval, 3.02-3.95) were the strongest factors associated with thromboprophylaxis administration. Thromboprophylaxis administration was not associated with surgical site infection (0.9% vs 0.6%; odds ratio, 1.48; 95% confidence interval, 0.80-2.74), bleeding complications (0.2% vs 0.1%; odds ratio, 2.60; 95% confidence interval, 0.99-6.80), or postpartum readmission (0.9% vs 0.3%; adjusted odds ratio, 1.38; 95% confidence interval, 0.68-2.81). The overall rate of venous thromboembolism was 0.06% (95% confidence interval, 0.03%-0.10%) and was higher in those receiving prophylaxis (0.2%) compared with those not receiving prophylaxis (0.04%).

CONCLUSION

Approximately 1 in 10 patients received postpartum pharmacologic thromboprophylaxis in this US cohort. Rates of prophylaxis varied widely by institution. Cesarean delivery, hysterectomy, and obesity were predominant factors associated with postpartum thromboprophylaxis administration.

The association between parental age differences and perinatal outcomes

STUDY QUESTION

Are there significant associations existing between parental age differences and adverse perinatal outcomes?

SUMMARY ANSWER

Large differences in parental age are associated with adverse perinatal outcomes, particularly with older mothers paired with younger fathers.

WHAT IS KNOWN ALREADY

The association between advanced maternal age and perinatal outcomes is well-documented with women over 35 years showing an increased risk of several adverse outcomes. Other studies have identified potential associations between advanced paternal age and adverse perinatal outcomes.

STUDY DESIGN, SIZE, DURATION

A historical (retrospective) cohort analysis was performed utilizing a multivariable logistic regression model to evaluate the association between varying differences in parental age and adverse perinatal outcomes while controlling for demographic and health-related covariates. Data were compiled from the National Vital Statistics System for 20 613 704 births between 2012 and 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Parental age differences, categorized into eleven 4-year intervals, were stratified by seven maternal age categories and evaluated for their associations with adverse perinatal outcomes. Main outcome measures included low birth weight, very low birth weight, preterm birth, very preterm birth, small size for gestational age, low 5-min appearance, pulse, grimace, activity, and respiration score, congenital defects, and chromosomal anomalies.

MAIN RESULTS AND THE ROLE OF CHANCE

Increased parental age differences, in either direction, were associated with significant risks for all adverse outcomes, aside from congenital defects, even when controlling for maternal age. Restricting maternal age to the reference range of 25-29 years, infants born to fathers aged 9-12 years younger (n = 3773) had 27% (odds ratio (OR) 1.27, 95% CI, 1.17-1.37) higher odds of having any adverse perinatal outcome. Infants born to fathers aged >16 years older (n = 98 555) had 14% (OR 1.14, 95% CI, 1.12-1.16) higher odds of having any adverse perinatal outcome.

LIMITATIONS, REASONS FOR CAUTION

Data extracted from US birth certificates may be compromised by errors in reporting or documentation. Information regarding the mother's socioeconomic status was estimated using proxy variables and may be susceptible to uncontrolled factors. Use of a pre-compiled dataset may potentially exclude additional maternal comorbidities that could impact perinatal outcomes.

WIDER IMPLICATIONS OF FINDINGS

Older mothers paired with younger fathers demonstrated the highest risk, even when maternal age was below the threshold of 35 years. For the clinical setting, parental age differences should be considered alongside maternal and paternal age when assessing risks of adverse perinatal outcomes for potential parents. This is particularly relevant for older women with younger male partners as this may exacerbate the impact of advanced maternal age.

STUDY FUNDING/COMPETING INTEREST(S)

This research was funded by the NIH Research Fellowship T35 Training Grant. There are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Validation of Three Models for Prediction of Blood Transfusion during Cesarean Delivery Admission

OBJECTIVE

 Prediction of blood transfusion during delivery admission allows for clinical preparedness and risk mitigation. Although prediction models have been developed and adopted into practice, their external validation is limited. We aimed to evaluate the performance of three blood transfusion prediction models in a U.S. cohort of individuals undergoing cesarean delivery.

STUDY DESIGN

 This was a secondary analysis of a multicenter randomized trial of tranexamic acid for prevention of hemorrhage at time of cesarean delivery. Three models were considered: a categorical risk tool (California Maternal Quality Care Collaborative [CMQCC]) and two regression models (Ahmadzia et al and Albright et al). The primary outcome was intrapartum or postpartum red blood cell transfusion. The CMQCC algorithm was applied to the cohort with frequency of risk category (low, medium, high) and associated transfusion rates reported. For the regression models, the area under the receiver-operating curve (AUC) was calculated and a calibration curve plotted to evaluate each model's capacity to predict receipt of transfusion. The regression model outputs were statistically compared.

RESULTS

 Of 10,785 analyzed individuals, 3.9% received a red blood cell transfusion during delivery admission. The CMQCC risk tool categorized 1,970 (18.3%) individuals as low risk, 5,259 (48.8%) as medium risk, and 3,556 (33.0%) as high risk with corresponding transfusion rates of 2.1% (95% confidence interval [CI]: 1.5-2.9%), 2.2% (95% CI: 1.8-2.6%), and 7.5% (95% CI: 6.6-8.4%), respectively. The AUC for prediction of blood transfusion using the Ahmadzia and Albright models was 0.78 (95% CI: 0.76-0.81) and 0.79 (95% CI: 0.77-0.82), respectively (p = 0.38 for difference). Calibration curves demonstrated overall agreement between the predicted probability and observed likelihood of blood transfusion.

CONCLUSION

 Three models were externally validated for prediction of blood transfusion during cesarean delivery admission in this U.S.

COHORT

Overall, performance was moderate; model selection should be based on ease of application until a specific model with superior predictive ability is developed.

KEY POINTS

· A total of 3.9% of individuals received a blood transfusion during cesarean delivery admission.. · Three models used in clinical practice are externally valid for blood transfusion prediction.. · Institutional model selection should be based on ease of application until further research identifies the optimal approach..

Coronavirus Disease 2019 (COVID-19) and Venous Thromboembolism During Pregnancy and Postpartum

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with increased risk for macro- and micro-thrombi. Consensus guidelines recommend use of thromboprophylaxis in nonobstetric patients with SARS-CoV-2 infection admitted to the hospital. National-level studies evaluating venous thromboembolism (VTE) among pregnant and postpartum individuals with and without SARS-CoV-2 infection have not been completed. We performed a retrospective cohort study of individuals aged 18 years or older delivering at more than 20 weeks of gestation with data in the MarketScan Commercial Insurance Database from 2016 through 2020. Of 811,008 deliveries, SARS-CoV-2 infection during pregnancy or through 6 weeks postpartum was associated with increased risk for VTE compared with no infection (1.0% vs 0.5%, adjusted hazard ratio 2.62, 95% CI 1.60-4.29). Findings support further consideration of thromboprophylaxis in the obstetric population with SARS-CoV-2 infection.

Thrombotic Markers in Pregnant Patients with and without SARS-CoV-2 Infection

BACKGROUND

 Coronavirus disease 2019 (COVID-19) is associated with coagulation abnormalities and increased risk for venous and arterial thrombi. This study aimed to evaluate D-dimer levels and lupus anticoagulant (LAC) positivity in pregnant individuals with and without Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

STUDY DESIGN

 This was a prospective cohort study of pregnant individuals delivering at a single academic institution from April 2020 to March 2022. Individuals with a positive SARS-CoV-2 result during pregnancy were compared with a convenience sample of those without a positive SARS-CoV-2 result. For individuals with SARS-CoV-2 infection, severity was assessed based on the National Institutes of Health classification system. The primary outcome was D-dimer level measured during delivery admission. The secondary outcomes were LAC positivity and thromboembolic events. Outcomes were compared between individuals with and without a positive SARS-CoV-2 result, and further by disease severity.

RESULTS

 Of 98 participants, 77 (78.6%) were SARS-CoV-2 positive during pregnancy. Among individuals with SARS-CoV-2 infection, severity was asymptomatic in 20 (26.0%), mild in 13 (16.9%), moderate in 4 (5.2%), severe in 38 (49.4%), and critical in 2 (2.6%). The D-dimer concentration at delivery did not significantly differ between those with a SARS-CoV-2 positive result compared with those without (mean 2.03 µg/mL [95% confidence interval {CI} 1.72-2.40] vs. 2.37 µg/mL [95% CI 1.65-3.40]; p = 0.43). Three individuals (4%) with SARS-CoV-2 infection and none (0%) without infection were LAC positive (p = 0.59). There were no clinically apparent thromboses in either group. D-dimer concentrations and LAC positive results did not differ by COVID-19 severity.

CONCLUSION

 Thrombotic markers did not differ in pregnant individuals by SARS-CoV-2 infection; however, high rates of LAC positivity were detected.

KEY POINTS

· Thrombotic markers did not differ in pregnant individuals by SARS-CoV-2 infection.. · Higher than expected rates of LAC positivity were detected.. · There were no clinically apparent thromboses..

Hypertensive disorders of pregnancy pre- and postaspirin guideline publication in individuals with pregestational diabetes mellitus

BACKGROUND

The US Preventive Services Taskforce published guidelines in 2014 recommending that low-dose aspirin be initiated between 12 and 28 weeks of gestation among high-risk patients for preeclampsia prophylaxis. Moreover, low-dose aspirin is recommended by some clinicians for the prevention of preterm birth.

OBJECTIVE

This study aimed to evaluate whether there is an association between the US Preventive Services Taskforce aspirin guideline hypertensive disorders of pregnancy and the rates of hypertensive disorders of pregnancy and preterm birth in individuals with pregestational diabetes mellitus.

STUDY DESIGN

This was a repeated cross-sectional analysis of individuals with pregestational diabetes mellitus and at least 1 singleton delivery at >20 weeks of gestation with records available in the National Vital Statistics System between 2010 and 2018. The primary outcome was hypertensive disorders of pregnancy, and the secondary outcome was preterm birth. Demographics and clinical characteristics among individuals in the pre-US Preventive Services Taskforce guideline cohort (2010-2013) were compared with that of individuals in the post-US Preventive Services Taskforce guideline cohort (2015-2018). Multivariable regression estimated the odds ratios and 95% confidence intervals for the association between guideline publication and the selected endpoints. Effect modification was assessed for access to prenatal care using the Kotelchuck Index (<80% vs ≥80%). Furthermore, a sensitivity analysis limited to nulliparas was performed.

RESULTS

Overall, 224,065 individuals were included. Individuals in the post-US Preventive Services Taskforce guideline cohort were more likely to be older, be obese, and have a history of preterm birth. In unadjusted and adjusted modeling, delivery in the post-US Preventive Services Taskforce guideline cohort was associated with hypertensive disorders of pregnancy (adjusted odds ratio, 1.25; 95% confidence interval, 1.22-1.28) and preterm birth (adjusted odds ratio, 1.10; 95% confidence interval, 1.08-1.12). The adjusted odds ratios for hypertensive disorders of pregnancy and preterm birth were more pronounced among those with less than adequate access to care. The findings were similar in the sensitivity analysis of only nulliparas.

CONCLUSION

Delivery after US Preventive Services Taskforce aspirin guideline publication was associated with higher rates of hypertensive disorders of pregnancy and preterm birth in a population of individuals with diabetes mellitus. It is unknown whether patient or practitioner factors, or other changes in obstetrical care, contributed to these findings.

Association Between Periviable Delivery and New Onset of or Exacerbation of Existing Mental Health Disorders

OBJECTIVE

To evaluate whether there is an association between periviable delivery and new onset of or exacerbation of existing mental health disorders within 12 months postpartum.

METHODS

We conducted a retrospective cohort study of individuals with liveborn singleton neonates delivered at 22 or more weeks of gestation from 2008 to 2017 in the MarketScan Commercial Research Database. The exposure was periviable delivery , defined as delivery from 22 0/7 through 25 6/7 weeks of gestation. The primary outcome was a mental health morbidity composite of one or more of the following: emergency department encounter associated with depression, anxiety, psychosis, posttraumatic stress disorder, adjustment disorder, self-harm, or suicide; new psychotropic medication prescription; new behavioral therapy visit; and inpatient psychiatry admission in the 12 months postdelivery. Secondary outcomes included components of the primary composite. Those with and without periviable delivery were compared using multivariable logistic regression adjusted for clinically relevant covariates, with results reported as adjusted incident rate ratios (aIRRs). Effect modification by history of mental health diagnoses was assessed. Incidence of the primary outcome by 90-day intervals postdelivery was assessed.

RESULTS

Of 2,300,244 included deliveries, 16,275 (0.7%) were periviable. Individuals with periviable delivery were more likely to have a chronic health condition, to have undergone cesarean delivery, and to have experienced severe maternal morbidity. Periviable delivery was associated with a modestly increased risk of the primary composite outcome, occurring in 13.8% of individuals with periviable delivery and 11.0% of individuals without periviable delivery (aIRR 1.18, 95% CI 1.12-1.24). The highest-risk period for the composite primary outcome was the first 90 days in those with periviable delivery compared with those without periviable delivery (51.6% vs 42.4%; incident rate ratio 1.56, 95% CI 1.47-1.66).

CONCLUSION

Periviable delivery was associated with a modestly increased risk of mental health morbidity in the 12 months postpartum.

Trends in Attempted and Successful Trial of Labor After Cesarean Delivery in the United States From 2010 to 2020

The vaginal birth after cesarean (VBAC) delivery rate was last reported as 13.8% in 2019. However, contemporary trends in attempted and successful trial of labor after cesarean (TOLAC) delivery among individuals with prior cesarean delivery have not been evaluated. We performed a repeated cross-sectional analysis of singleton, cephalic, term deliveries in individuals with a history of one or two cesarean deliveries in the National Vital Statistics System from 2010 to 2020. Temporal trends in attempted and successful TOLAC, as well as VBAC, were characterized using joinpoint regression. Overall, 4,277,800 deliveries were included. Attempted TOLAC increased from 15.3% in 2010 to 21.7% in 2020, with an annual percent increase (relative) of 4.25% (95% CI 2.9-5.6%). Successful TOLAC increased from 69.8% to 74.7%, with an annual percent change (relative) of 0.91% (95% CI 0.7-1.2%). The VBAC rate similarly increased such that, by 2020, it was 16.2%.

Adjunct Therapy at Time of Examination-Indicated Cervical Cerclage in Singleton Pregnancies: A Systematic Review and Meta-analysis

OBJECTIVE

Physical examination-indicated cerclage for cervical insufficiency prolongs gestation, but evidence on the addition of adjuncts to further prolong latency is limited. The aim of this systematic review and meta-analysis was to compare gestational latency between those who did and did not receive adjunct antibiotic or tocolytic therapy at the time of examination-indicated cerclage.

STUDY DESIGN

Electronic databases (1966-2020) were searched for randomized controlled trials (RCTs) and cohort studies comparing adjunct antibiotic or tocolytic use versus nonuse at time of examination-indicated cerclage, defined as placement for cervical dilation ≥1 cm, in a current singleton pregnancy. Studies including individuals with intra-amniotic infection, cerclage in place, nonviable gestation, or ruptured membranes were excluded. The primary outcome was latency from cerclage placement to delivery. Secondary outcomes included preterm birth, preterm premature rupture of membranes, birth weight, and neonatal survival. Risk of bias was assessed using standardized tools. Heterogeneity was assessed using χ 2 and I 2 tests. Results were pooled and analyzed using a random-effects model. This study is registered with The International Prospective Register of Systematic Reviews (PROSPERO) with registration no.: CRD42021216370.

RESULTS

Of 923 unique records, 163 were reviewed in full. Three met inclusion criteria: one RCT and two retrospective cohorts. The included RCT (n = 50) and one cohort (n = 142) compared outcomes with and without adjunct use of antibiotic and tocolytic, while the second cohort (n = 150) compared outcomes with and without adjunct tocolytic, with a subpopulation also receiving antibiotics. The RCT was nested within one of the cohorts, and therefore only one of these two studies was utilized for any given outcome to eliminate counting individuals twice. Risk of bias was "critical" for one cohort study, "moderate" for the other cohort study, and "some concerns" for the RCT. Gestational latency could not be pooled and meta-analyzed. Adjunct tocolytic-antibiotic therapy was not associated with a decrease in risk of preterm delivery <28 weeks (relative risk [RR] = 0.90, 95% confidence interval [CI]: 0.65-1.26; χ 2 = 0.0, I 2 = 0.0%) or neonatal survival to discharge (RR = 1.11, 95% CI: 0.91-1.35; χ 2 = 0.05, I 2 = 0.0%).

CONCLUSION

There is not enough evidence to robustly evaluate the use of adjunct tocolytics or antibiotics at time of examination-indicated cerclage to prolong latency.

KEY POINTS

· Limited data on adjunct antibiotic tocolytics at cerclage.. · Widely variable practices at time of cerclage identified.. · Role of adjunct therapies at time of examination-indicated cerclage remains unclear..

Agreement Between Pregnant Individuals' Self-Report of Coronavirus Disease 2019 (COVID-19) Vaccination and Medical Record Documentation

For public health research such as vaccine uptake or effectiveness assessments, self-reported coronavirus disease 2019 (COVID-19) vaccination status may be a more efficient measure than verifying vaccination status from medical records if agreement between sources is high. We assessed agreement between self-reported and medical record-documented COVID-19 vaccination status among pregnant individuals followed in a cohort during August 2020-October 2021. At end of pregnancy, participants completed questionnaires about COVID-19 vaccine receipt during pregnancy; staff verified vaccination status using medical records. Agreement was assessed between self-reported and medical record vaccination status using Cohen's kappa. There was high agreement between self-reported and medical record vaccination status (Kappa coefficient=0.94, 95% CI 0.91-0.98), suggesting that self-report may be acceptable for ascertaining COVID-19 vaccination status during pregnancy.

Marijuana use, fetal growth, and uterine artery Dopplers

OBJECTIVE

Marijuana (MJ) use is associated with adverse effects on fetal growth. We aimed to investigate the timing of suboptimal fetal growth onset in MJ-exposed pregnancies. In addition, we aimed to explore the relationship between MJ-exposure and both abnormal uterine artery (UtA) Doppler parameters and small for gestational age (SGA).

STUDY DESIGN

This was a secondary analysis of a prospective multicenter cohort that enrolled nulliparous individuals delivering non-anomalous fetuses beyond 20 weeks' gestation. Marijuana exposure was ascertained by self-report or clinical urine toxicology testing. Ultrasound estimated fetal weights (EFWs) were assessed in participants at both 16w0d-21w6d and 22w0d-29w6d. EFWs and birth weight (BW) were converted to weight percentiles (wPCT). EFW and BW wPCTs were calculated using population-based standards. Additionally, a customized standard designed to be applicable to both EFWs and BWs within the same model was also used to allow for EFW to BW percentile trajectories. The primary outcome, longitudinal wPCT, was compared between individuals with and without MJ use in a linear mixed-effects regression model adjusting for tobacco. For modeling, wPCT was smoothed across gestational age; MJ was estimated as an intercept and linear difference in the slope of gestational age. UtA Doppler notching, resistance index (RI), and pulsatility index (PI) at 16w0d-21w6d were compared using t-test and χ2. SGA at delivery was also compared.

RESULTS

Nine thousand one hundred and sixty-three individuals met inclusion criteria; 136 (1.5%) used MJ during pregnancy. Individuals who used MJ were more likely to be younger, identify as non-Hispanic Black, and have had less education. Fetuses exposed to MJ had lower wPCT beginning at 28 weeks using population-based and customized standards, when compared to those without exposure. UtA notching, PI, and RI were similar between groups. SGA was more frequent in neonates exposed to MJ using both population-based (22 vs. 9%, p<.001) and customized (25 vs. 14%, p<.001) curves.

CONCLUSIONS

MJ-exposed fetuses were estimated to be smaller than unexposed fetuses starting at 28 weeks' gestation across both growth standards without a difference in UtA Doppler parameters.

Prophylactic Ureteral Stent Placement and Urinary Injury During Hysterectomy for Placenta Accreta Spectrum

OBJECTIVE

To evaluate the association between prophylactic ureteral stent placement at the time of hysterectomy for placenta accreta spectrum and genitourinary injury.

METHODS

We conducted a retrospective cohort study of patients with placenta accreta spectrum who underwent hysterectomy at two referral centers from 2001 to 2021. The exposure was prophylactic ureteral stent placement. The primary outcome, genitourinary injury, was a composite of bladder injury, ureteral injury, or vesicovaginal fistula. Secondary outcomes included components of the primary outcome. We evaluated differences between groups using χ 2 and t test. To evaluate differences in the primary outcome, we reported odds ratios (ORs) and adjusted odds ratios (aORs) using multivariable logistic regression analyses to control for potential confounding variables. We used a Cochran-Armitage χ 2 trend test to evaluate difference in stent use and injury over time.

RESULTS

In total, 236 patients were included. Prophylactic ureteral stents were used in 156 surgeries (66%). Overall, genitourinary injury occurred less frequently in the stent group compared with the no stent group (28% vs 51%, OR 0.37, 95% CI 0.21-0.65). This association persisted after controlling for urgency of delivery, three or more prior cesarean deliveries, and whether a gynecologic oncologist was present (aOR 0.27, 95% CI 0.14-0.52). Unintentional bladder injury occurred less frequently in the stent group compared with the no stent group (13% vs 25%, P =.018), as did ureteral injury (2% vs 9%, P =.019).

CONCLUSION

Prophylactic ureteral stent placement was associated with a decreased risk of genitourinary injury during hysterectomy for placenta accreta spectrum.

Weight-Based Compared With Fixed-Dose Enoxaparin Prophylaxis After Cesarean Delivery: A Randomized Controlled Trial

OBJECTIVE

To evaluate fixed compared with weight-based enoxaparin dosing to achieve prophylactic anti-Xa levels after cesarean delivery.

METHODS

Individuals meeting institutional criteria for enoxaparin thromboprophylaxis after cesarean delivery were randomly allocated to fixed (40 mg daily for body mass index [BMI, calculated as weight in kilograms divided by height in meters squared] lower than 40; 40 mg every 12 hours for BMI 40 or higher) or weight-based (0.5 mg/kg every 12 hours) enoxaparin dosing. Enoxaparin was initiated during inpatient hospitalization and continued at discharge for 14 days. Those with contraindication to anticoagulation, plan for therapeutic anticoagulation, or known renal impairment were excluded. The trial was unmasked. The primary outcome was prophylactic (0.2-0.6 international units/mL) peak anti-Xa level 4-6 hours after at least the third enoxaparin dose (at steady state). Secondary outcomes included subprophylactic and supraprophylactic peaks, outpatient peak, and venous thromboembolism (VTE) and wound complications in the first 6 weeks postpartum. Sample size of 121 per group was planned. At interim analysis with 50% enrollment, the trial was stopped early for efficacy. Primary analyses followed intention-to-treat principle with worst-case imputation for missing outcomes. Secondary analyses were complete case.

RESULTS

From June 2020 to November 2021, 74 individuals were randomized to weight-based enoxaparin and 72 to fixed-dose enoxaparin. Those who received weight-based dosing were more likely to achieve prophylactic anti-Xa levels than those who received fixed dosing in primary analysis (49/74 [66%] vs 32/72 [44%], relative risk [RR] 1.49, 95% CI 1.10-2.02) and secondary analysis (49/60 [82%] vs 32/57 [56%], RR 1.45, 95% CI 1.12-1.88). Subprophylactic levels occurred more frequently with fixed dosing; supraprophylactic levels did not differ significantly by dosing. At the outpatient postoperative visit, 52% of participants (15/29) with weight-based dosing compared with 15% (5/33) with fixed dosing achieved prophylactic peak anti-Xa level (RR 3.41, 95% CI 1.42-8.24). There were no VTEs in either group. Wound complications occurred in five individuals (7%) with weight-based enoxaparin dosing compared with one individual (1%) with fixed enoxaparin dosing (RR 4.86, 95% 0.58-40.63).

CONCLUSION

Weight-based dosing was more effective than fixed enoxaparin dosing in achieving prophylactic peak anti-Xa levels after cesarean delivery.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT04305756.

Trends in Hypertensive Disorders of Pregnancy in the United States From 1989 to 2020

Hypertensive disorders of pregnancy affect up to 8% of pregnancies, but updated national trends are lacking. We performed a repeated cross-sectional analysis of individuals with singleton pregnancies who delivered at greater than 20 weeks of gestation, with data in the U.S. National Vital Statistics System from 1989 to 2020. Temporal trends in hypertensive disorders of pregnancy, chronic hypertension, and eclampsia were characterized using joinpoint regression. Overall, 122,329,914 deliveries were included. Hypertensive disorders of pregnancy increased from 2.79% in 1989 to 8.22% in 2020, representing an average annual percentage change (AAPC) of 3.6% (95% CI 3.0-4.1%). Chronic hypertension increased (AAPC 4.1%, 95% CI 3.3-4.9%), whereas eclampsia decreased (AAPC -2.5%, 95% CI -4.0% to -1.0%). Hypertensive disorders of pregnancy are associated with significant morbidity and mortality; the rising incidence is concerning.

Challenges in Interpreting Obstetrics and Gynecology Literature

The field of obstetrics and gynecology is constantly replenished with the newest research findings. In an era of rapidly available study publications, there are a number of challenges to interpreting the obstetrics and gynecology literature. Common pitfalls include the over reliance on the dichotomized P-value, lack of transparency, bias in study reporting, limitations of resources, absence of standardized practices and outcomes in study design, and the rare concerns for data integrity. We review these predominant challenges and their potential solutions, in interpreting the obstetrics and gynecology literature.

Impact of the p-Value Threshold on Interpretation of Trial Outcomes in Obstetrics and Gynecology

OBJECTIVE

Randomized controlled trials (RCTs) are considered the highest level of evidence to inform clinical practice. However, the reproducibility crisis has raised concerns about the scientific rigor of published RCT findings. Some advocate for a lower p-value threshold. We aimed to review published OB/Gyn topical RCTs in three representative OB/Gyn journals and three high impact non-OB/Gyn journals to determine if their interpretations would change with adoption of a p-value threshold for significance of 0.005. Secondarily, we evaluated if there were differences in methodologic characteristics between those that did and did not lose significance.

STUDY DESIGN

A manual search was performed to identify all OB/Gyn RCTs published in the selected journals between July 2017 and June 2019. Data were collected on primary outcome(s), methodology, and p-values. We determined the proportion of primary outcomes that would remain statistically significant with adoption of a p-value significance threshold of 0.005 versus be reinterpreted as "suggestive" (defined as p-value between 0.005 and 0.05). Chi-square or Fisher's exact test were used to compare study characteristics.

RESULTS

Overall, 202 RCTs met inclusion criteria; 52% in obstetrics and 48% in gynecology. Of 90 studies considered significant with p <0.05 at the time of publication, 54.4% (n = 49) would maintain significant (p < 0.005), while 45.6% (n = 41) would become suggestive using the lower threshold. Most RCTs utilized a single (90.1%) versus composite (8.9%) primary outcome type, used an intent-to-treat analysis (73.3%), and studied a drug intervention (46.5%). Methodologically, 23.7% did not prespecify analysis type, 28.2% did not meet the pre-determined sample size, and 9.4% did not report an a priori sample size calculation. Studies maintaining significance were more likely to be international and report a funding source.

CONCLUSION

Adopting a p-value significance threshold of 0.005 would require reinterpretation of almost half of RCT results in the OB/Gyn literature. Highly variable methodological quality was identified.

KEY POINTS

· New p-value threshold results in reinterpretation of nearly half of RCT results in OB/Gyn literature.. · Highly variable methodological quality was identified.. · Reduced use of binary interpretations of significance is necessary..

Performance of middle cerebral artery doppler for prediction of recurrent fetal anemia

OBJECTIVE

To assess the predictive value of middle cerebral artery Doppler peak systolic velocity (MCA-PSV) for moderate-severe fetal anemia following one intrauterine transfusion (IUT) and test the performance of alternate cutoffs to the recommended threshold ≥1.69 multiples of the median (MoM).

METHODS

This was a retrospective cohort study of patients with pregnancies affected by alloimmunization who underwent percutaneous umbilical blood sampling (PUBS) procedures from 2000 to 2020. An MCA-PSV ≥1.69 MoM was the indication for the second IUT. The primary outcome was recurrent moderate-severe fetal anemia. Receiver-operating characteristic (ROC) curves assessed the predictive ability of MCA-PSV for the primary outcome and the Youden index identified the "optimal" cutoff value. Predictive characteristics of MCA-PSV ≥1.69 MoM and the "optimal" cutoff were compared.

RESULTS

Of the 58 patients who underwent IUT during the study period, 36 (62%) did not meet inclusion criteria. Of the remaining 22 patients who underwent a second PUBS, 12 (54.6%) fetuses had moderate or severe anemia. Following one IUT, the AUC for MCA-PSV was 0.86 (95% CI 0.70-1.00) for the primary outcome. The "optimal" cutoff MCA-PSV value was 1.74 MoM, which had a greater specificity than ≥1.69 MoM (90 vs. 50%, p = .05), but was not statistically significant. The sensitivity was similar between the two cutoff values of ≥1.69 and ≥1.74 MoM (83.3 vs. 75.0%, p = .65) (Table 2).

CONCLUSION

Raising the recommended MCA-PSV cutoff to ≥1.74 MoM for recurrent moderate-severe fetal anemia after one IUT would decrease the number of unnecessary procedures without significantly changing the sensitivity of this screening test.

Neonatal outcomes after percutaneous umbilical cord blood sampling†

Objectives: While percutaneous umbilical cord blood sampling (PUBS) and intrauterine transfusion (IUT) are the standards of care for the management of significant fetal anemia, the neonatal complications resultant from these procedures remain poorly understood. Thus, we aimed to compare neonatal outcomes of the patients undergoing percutaneous umbilical cord blood sampling (PUBS) for intrauterine transfusion (IUT) to gestational age- and sex-matched controls with no indication for and not undergoing PUBS.Methods: This was a retrospective matched cohort study at a single institution from 2000 to 2017. Clinical and demographic data were abstracted from the medical record of patients undergoing PUBS. Neonatal outcomes from pregnancies undergoing PUBS for suspected fetal anemia and from randomly selected gestational age- and sex-matched controls were collected. Neonatal outcomes were compared using matched pairs analysis.Results: There were 64 patients who underwent a total of 178 PUBS with 157 IUT. The most common etiology of fetal anemia was anti-D alloimmunization. On an average, patients undergoing PUBS underwent two procedures (IQR 1,4). There were available neonatal outcomes in 40 patients. The median gestational age at delivery was 34 weeks in both neonates who underwent PUBS and controls. In matched pairs analysis, neonates who underwent PUBS were at higher risk for neonatal complications compared to control neonates (92.5 vs. 55%, OR 4.5, 95% CI 4.5, ∞) . Specifically, neonates who underwent PUBS were more likely to experience respiratory complications compared to controls despite a higher uptake of antenatal corticosteroids.Conclusions: We found that neonates who underwent PUBS experience a higher occurrence of complications which does not appear to be secondary to prematurity alone. Despite higher uptake of antenatal corticosteroids in neonates who underwent PUBS as compared to control neonates, neonates who underwent PUBS had a higher risk of respiratory complications. This study can help to inform patients undergoing PUBS/IUT on the anticipated neonatal outcomes and anticipate needed neonatology resources. While PUBS/IUT is the best treatment known to date for management of fetal anemia, our study highlights the need for further research into the subsequent neonatal complications and how to prevent them.

Acidemia Can Occur Despite Category I Tracing

OBJECTIVE

Electronic fetal monitoring (EFM) is intended to assess fetal well-being during labor. Our objective was to test the hypothesis that findings of a category I tracing at any time in the 60 minutes prior to delivery would rule out neonatal acidemia.

STUDY DESIGN

This was a planned secondary analysis of a single-center prospective cohort study of 8,580 singleton pregnancies undergoing labor with nonanomalous infants at term. Monitoring was reviewed by obstetric research nurses at 10-minute intervals in the 60 minutes prior to delivery. The primary outcome was acidemia, defined as an umbilical cord arterial pH of 7.10 or less.

RESULTS

Of the 4,274 patients included, 42 (0.98%) infants had acidemia at birth. Of the 42 infants with acidemia, 13 (31%) had category I tracings in the 30 minutes prior to delivery. Three (7%) infants had neonatal acidemia despite category I tracing for >40 minutes in the 60 minutes prior to delivery.

CONCLUSION

Even in the presence of category I tracing in the 60 minutes prior to delivery, neonatal acidemia can still occur. Periods of category I should be interpreted within the clinical context of a priori risk for acidemia, knowing that it does not completely rule out acidemia.

Fetal thrombocytopenia in pregnancies complicated by fetal anemia due to red-cell alloimmunization: cohort study and meta-analysis

OBJECTIVE

To estimate the prevalence and characteristics of fetal thrombocytopenia at the time of percutaneous umbilical cord sampling (PUBS) in pregnancies complicated by alloimmunization and to conduct a systematic review on fetal thrombocytopenia in these pregnancies.

STUDY DESIGN

Retrospective cohort study of all patients undergoing PUBS at our institution from 2000-2017. Clinical data, including fetal platelet counts, were abstracted from the medical record and analyzed with routine statistical procedures. A systematic review and meta-analysis were also conducted according to standard procedures.

RESULT

At first procedure, prior to any transfusion, 13/36 fetuses (36%) had thrombocytopenia: 11/36 (31%) had moderate thrombocytopenia and 2/36 (6%) had severe thrombocytopenia (14 patients had no platelet count at first procedure). The systematic review identified six studies, and the prevalence of fetal thrombocytopenia at the time of PUBS for alloimmunization was 18% (95% confidence interval 11%, 26%).

CONCLUSION

Thrombocytopenia is common and underappreciated in fetuses undergoing PUBS for alloimmunization.

Delayed Introduction of Parenteral Phosphorus Is Associated with Hypercalcemia in Extremely Preterm Infants

BACKGROUND

Early parenteral nutrition (PN) provides essential macro- and micronutrients for extremely low birth weight (ELBW) infants <1000 g. Frequent cases of hypercalcemia [whole blood ionized calcium (iCa) > 1.45 mmol/L] in the first week of life while receiving PN solutions at our large quaternary center prompted investigation and 2 plan-do-study-act (PDSA) cycles to reduce rates of hypercalcemia.

OBJECTIVE

We compared 2 cohorts of ELBW infants separated by PDSA cycles to evaluate and reduce the incidence of abnormal iCa concentration.

METHODS

Data were recorded for 150 premature infants with mean birth weight of 726 ± 164 g, 48% male, and mean gestational age of 26 ± 2.1 wk. This process included an internal practice analysis and PDSA cycles monitored prospectively over 3 y. From December 2011 to September 2012, 66 infants received 0-1.2 mmol parenteral phosphorus supplementation/(kg ⋅ d) beginning at 72 h of life. In the second protocol, 84 infants born September 2012 to July 2013 received earlier phosphorus supplementation within 24 h of life. The peak whole blood iCa and serum phosphorus concentrations in the first week of life were monitored.

RESULTS

Early introduction of phosphorus was significantly associated with a decreased mean peak iCa (1.64 ± 0.27 mmol/L to 1.50 ± 0.23 mmol/L, P = 0.001), and the incidence of severe hypercalcemia (iCa > 1.60 mmol/L) decreased from 50.0% to 21.4% (P = 0.002) in the first week of life. There was no difference in mortality, bronchopulmonary dysplasia, renal calcifications, seizures within 7 d of birth, brain calcifications, or intracranial hemorrhage between cohorts.

CONCLUSION

Early introduction of phosphorus in PN solutions is associated with reduced incidence of whole blood iCa abnormalities in the first week of life and should be considered for ELBW infants. Ongoing evaluation of optimal mineral provision to this population after birth should be performed.

Human membrane metallo-endopeptidase-like protein degrades both beta-amyloid 42 and beta-amyloid 40

Beta-amyloid (Abeta) degrading endopeptidases are thought to protect against Alzheimer's disease (AD) and are potentially therapeutic. Of particular interest are endopeptidases that are blocked by thiorphan and phosphoramidon (T/P), as these inhibitors rapidly induce Abeta deposition in rodents. Neprilysin (NEP) is the best known target of T/P; however neprilysin knockout results in only modest Abeta increases insufficient to induce deposition. Therefore, other endopeptidases targeted by T/P must be critical for Abeta catabolism. Another candidate is the T/P sensitive membrane metallo-endopeptidase-like protein (MMEL), a close homolog of neprilysin. The endopeptidase properties of beta and gamma splice forms of human MMEL were determined in HEK293T cells transduced with the human cDNAs for the two splice forms; this showed degradation of both Abeta(42) and Abeta(40) by hMMEL-beta but not hMMEL-gamma. hMMEL-beta activity was found at the extracellular surface with no significant secreted activity. hMMEL-gamma was not expressed at the extracellular surface. Finally, it was found that hMMEL cleaves Abeta near the alpha-secretase site (producing Abeta(1-17)>>Abeta(1-16)). These data establish hMMEL as a mediator of Abeta catabolism and raise the possibility of its involvement in the etiology of AD and as a target for intervention.

Phenazine 5,10-dioxide derivatives as hypoxic selective cytotoxins: Part II. Structure-activity relationship studies

The synthesis and evaluation as hypoxic selective cytotoxins of new derivatives of 2-amino or 2-hydroxyphenazine 5,10-dioxide are described. The compounds were developed as structural analogs of other bioreductive compounds and its in vitro cytotoxicities on V79 cells under hypoxic and aerobic conditions were determined. To gain insight into its mechanism of action electrochemical behavior, interaction with DNA experiments and QSAR studies were performed.

Monoarylhydrazones of alpha-lapachone: synthesis, chemical properties and antineoplastic activity

The biological activities of the naphthoquinones lapachol, extracted from trees of the genus Tabebuia and its cyclization products alpha and beta-lapachone, have been intensively studied. Giving continuity to the research about new derivatives obtained from the reaction of these naphthoquinones with amino-containing reagents, a series of arylhydrazones of alpha-lapachone was synthesized and their antineoplastic activity was evaluated. This new structure is based on the great electrophilicity of 1,4-quinoidal carbonyl groups towards reagents containing nitrogen as nucleophilic centers, such as arylhydrazines. The products were assayed by the National Cancer Institute (NCI, USA) and their binding to DNA, redox properties and QSAR studies were also determined.

Bis-naphthylureas and related compounds: synthesis, chemical properties, DNA affinity and antineoplastic activity

A series of bis-naphthalene derivatives in which these moieties are linked by a symmetric bis-urea functionalized chain or by an asymmetric amide and urea or amino and urea functionalized chain, were synthesized. The tentative synthesis of other types of related compounds did not give the products expected. The compounds were assayed as antineoplastics on human tumor cell lines at the National Cancer Institute (USA). Bis-urea derivatives were active on lung, colon, renal and CNS tumor cell lines. The degree of affinity of these compounds to DNA was also studied, showing low affinity.

Synthesis and biological evaluation of 1,2,5-oxadiazole N-oxide derivatives as potential hypoxic cytotoxins and DNA-binders

Several new 1,2,5-oxadiazole N-oxide derivatives were synthesized to be tested both as potential selective hypoxic cell cytotoxins and as DNA-binding agents. The compounds prepared included bis(1,2,5-oxadiazole N-oxide) derivatives and oxadiazole rings linked to naphthyl residues. The compounds were tested for their cytotoxicity in oxia and hypoxia and they proved to be non-selective and less active than the parent compounds 3-formyl-4-phenyl-1,2,5-oxadiazole N2-oxide (3) and 3-chloromethyl-4-phenyl-1,2,5-oxadiazole N2-oxide (4). The DNA-affinity assays showed that the compounds tested have poor affinity for this biomolecule.

Benzothiadiazine dioxide dibenzyl derivatives as potent human cytomegalovirus inhibitors: synthesis and comparative molecular field analysis

The benzothiadiazine dioxide (BTD) derivatives are potent nonnucleoside human cytomegalovirus (HCMV) inhibitors. As part of our comprehensive structure-activity relationship study of these compounds, we have now synthesized N,N- and N,O-dibenzyl derivatives with different para-substituents (alkyl, phenyl, electron-donating, electron-withdrawing) in the phenyl ring of the benzyl moieties. The antiviral activity against HCMV (AD-169 strain) was also experimentally measured showing IC(50) values between 2.5 and 50 microM. Comparative molecular field analysis (CoMFA) was employed to generate a model, based upon 32 diverse BTD derivatives, to delineate structural and electrostatic features important for enhanced activity against HCMV. The steric (van der Waals) interactions with the receptor majoritary describes the variation in antiviral activity among the inhibitors. Finally, the CoMFA model was used to design two sets of novel BTD derivatives. Synthesis and subsequent anti-HCMV evaluation of these compounds enabled us to maintain the activity of this new kind of HCMV inhibitors.

Human DNA topoisomerase I poisoning activity of bis-1-aminomethylnaphtalenes. A correlation with their cytotoxic activity

Symmetrical bis-1-aminmoethylnaphtalenes, a group of compounds that demonstrated cytotoxicity towards human tumor cell lines, showed human topoisomerase I poisoning activity. The compounds tested were: N,N'-bis-1-naphthylmethyl-1,6-hexanediamine (1a), N,N'-bis-1-naphthylmethyl-1,8-octanediamine (1b), N,N'-bis-1-naphthylmethyl-1,12-dodecanediamine (1c), N,N'-bis-1-naphthylmethyl-4,4-bipiperidine (2) and N-(1-naphthylmethyl)-N'-dimethyl-1,3-diaminepropane dichlorhydrate (3). All showed human topoisomerase I inhibition by producing protein-linked DNA breaks. The most active were 1a, 1b, 1c with a percentage stimulation of DNA cleavage of 75, 84 and 70% at 100 micrograms/ml, respectively. Compounds 2 and 3 were moderately active as poisons of topoisomerase I activity, the former showing 58% stimulation of DNA cleavage at 100 micrograms/ml and the latter a 24% stimulation. The correlation observed between topoisomerase I poisoning and in vitro cytotoxic activity suggests that this could be a possible mechanism for the cytotoxicity observed in tumor cell lines.

Diarylsemicarbazones: synthesis, antineoplastic activity and topoisomerase I inhibition assay

A series of diarylsemicarbazones was synthesized and tested against human neoplastic cell lines. The more active members have a l-naphthyl ring at the carbamidic nitrogen, and chloro, dimethylamino or nitro group substituents at the benzylidene moiety. None of these showed affinity to DNA. One of the more active compounds was tested as a topoisomerase I inhibitor and showed a potent effect. SAR studies demonstrated linear correlation between lypophilicity and activity on the most sensitive lines and a definite conformational shape for antineoplastic action.

Synthesis, DNA interaction and antineoplastic activity of semicarbazone derivatives

A number of antineoplastic agents including procarbazine and bisantrene derive from hydrazine, but so far none have been developed from semicarbazide. In order to assay active minimal structures, thirteen new compounds were prepared by replacing hydrogen atoms in semicarbazone amine group by alkylamine moieties, employing an improved procedure. DNA binding was evaluated by treatment of a drug solution with DNA-cellulose complex and further measurement of remaining drug by UV spectroscopy and the affinity observed to range from medium to weak. On testing these compounds against human neoplastic cell lines, only a nitroderivative proved active on CNS and Breast cell lines at 10(-4) M. This member was studied by cyclic voltammetry.

DNA interaction and electrochemical properties of bis-1-aminomethylnaphthalenes and related compounds. A correlation with their antineoplastic activity

Bis-1-aminomethylnaphthalenes constitute a new type of molecule with antineoplastic activity. As a first approach to determine the action mechanism, the interaction degree of these compounds and some less active analogous, with calf thymus DNA, by UV spectrophotometry, and the redox performance by cyclic voltammetry was correlated with their activity on neoplastic cell lines. It suggests that the most active members interact closely with DNA but do not show any redox process at biological potentials.

Ampicillin plus mecillinam vs. cefotaxime/cefadroxil treatment of patients with severe pneumonia or pyelonephritis: a double-blind multicentre study evaluated by intention-to-treat analysis

In this double-blind multicentre study, using the intention-to-treat approach, a total of 293 patients with fever (> or = 38.5 degrees C), symptoms of sepsis and signs of pneumonia or pyelonephritis were randomly assigned to treatment with ampicillin and mecillinam (A+M) or cefotaxime followed by cefadroxil. In the febrile phase, treatment was given intravenously twice daily, either with 1,200 mg ampicillin together with 600 mg mecillinam or with 2 g cefotaxime alone. When the patients stayed afebrile, the intravenous administration was replaced by oral treatment twice daily for 14 days, either with 500 mg pivampicillin and 400 mg pivmecillinam or 1 g cefadroxil. In the A+M group, 33% (48/144) of the patients did not complete the full course of treatment as compared with 32% (47/149) in the cephalosporin group, the reasons being treatment failure in 27 and 29, respectively, or adverse effects (n = 16 in both groups). The median duration of fever was 47 h in the A + M group and 50 h in the cephalosporin group. Of 135 patients with pneumonia, 68% were completely cured in the A + M group, and 65% in the cephalosporin group, the main reasons for treatment failure being Mycoplasma pneumonia or ornithosis. Of 136 patients with pyelonephritis, 63% were cured in each group. The main reason for failure was bacteriological relapse. Side-effects were reported by 32 patients (22%) of the A+M group, as compared with 41 (28%) of the cephalosporin group. Epigastric complaints were equally frequent in both groups, but there was a tendency for a higher frequency of exanthema in the A+M group, and for antibiotic-associated diarrhoea and fungal superinfections in the cephalosporin group.

Chronic effects of transdermal nitroglycerin in stable angina pectoris: a within-patient, placebo-controlled study

The efficacy of transdermal nitroglycerin patches, releasing 20 mg of active substance over a period of 24 h (TDN 20), was investigated in 10 patients with stable exercise-induced angina pectoris. The study was divided into 3 periods: the first part was an acute, within-patient, crossover, double-blind, placebo-controlled study, in which patients performed a cycloergometric exercise test 4 and 24 h after the application of the patches (TDN 20 or placebo). During the 2nd period, patients were given TDN 20, in single blind conditions, for 4 weeks and another exercise test was performed, on the last day, 4 and 24 h after patch application. Finally, after a one-day placebo wash-out, a second acute study similar to the first was performed. Four h after dosing, exercise duration to 1 mm ST segment depression was 441 s and 314 s (p less than 0.01) for TDN 20 and placebo, respectively (first acute study), 394 s for TDN 20 after chronic treatment (p less than 0.001 vs acute placebo) and 472 and 354 s (p less than 0.001) for TDN 20 and placebo, respectively (second acute study). No difference in exercise duration to 1 mm ST segment depression was found between TDN 20 and placebo, 24 h after administration, in any of the periods. Blood pressure significantly decreased and heart rate significantly increased 4 h after TDN dosing (in comparison with placebo) in both the acute studies, but no difference was observed after chronic TDN treatment. In conclusion, TDN 20 increases exercise tolerance 4 h after the application of both acute and chronic treatments.(ABSTRACT TRUNCATED AT 250 WORDS)