Impact of Simulation Exercises on Total Laparoscopic Hysterectomy Surgical Outcomes: A Systematic Review and Meta-Analysis.

BACKGROUND: As resources into gynecological surgical simulation training increase, research showing an association with improved clinical outcomes is needed. OBJECTIVE: To evaluate the association between surgical simulation training for total laparoscopic hysterectomy (TLH) and rates of intraoperative vascular/visceral injury (primary outcome) and operative time. SEARCH STRATEGY: We searched Medline OVID, Embase, Web of Science, Cochrane, and CINAHL databases from the inception of each database to April 5, 2022. Selection Critera: Randomized controlled trials (RCTs) or cohort studies of any size published in English prior to April 4, 2022. DATA COLLECTION AND ANALYSIS: The summary measures were reported as relative risks (RR) or as mean differences (MD) with 95% confidence intervals using the random effects model of DerSimonian and Laird. A Higgins I2 >0% was used to identify heterogeneity. We assessed risk of bias using the Cochrane Risk of Bias tool 2.0 (for RCTs) and the Newcastle Ottawa Scale (for cohort studies). MAIN RESULTS: The primary outcome of this systematic review and meta-analysis was to evaluate the impact of simulation training on the rates of vessel/visceral injury in patients undergoing TLH. Of 989 studies screened 3 (2 cohort studies, 1 randomized controlled trial) met the eligibility criteria for analysis. There was no difference in vessel/visceral injury (OR 1.73, 95% CI 0.53-5.69, p=0.36) and operative time (MD 13.28, 95% CI -6.26 to 32.82, p=0.18) when comparing before and after simulation training. CONCLUSION: There is limited evidence that simulation improves clinical outcomes for patients undergoing TLH.

Unpublished completed obstetric randomized clinical trials registered at ClinicalTrials.gov: how big is this issue?

BACKGROUND: A portion of obstetrical randomized clinical trials registered on ClinicalTrials.gov are not published in peer-reviewed journals. OBJECTIVE: This study aimed to compare the characteristics of completed published vs unpublished randomized clinical trials in obstetrics registered on ClinicalTrials.gov and to identify barriers to publication. STUDY DESIGN: This cross-sectional study queried ClinicalTrials.gov for all completed obstetrical randomized clinical trials registered between January 1, 2009, and December 31, 2018. For each completed obstetrical randomized clinical trial, we abstracted the following registration fields from ClinicalTrials.gov: ClinicalTrials.gov identifier, recruitment status, trial start and completion dates, study results, type of intervention, study phase, enrollment size, funder type, location, and facilities. Calculated variables included time to completion. In May 2021, we used PubMed and Google Scholar to identify the publication status of completed trials, and we compared the characteristics of published vs unpublished randomized clinical trials. The corresponding authors' e-mail addresses for the unpublished studies were collected from ClinicalTrials.gov and departmental websites. Between September 2021 and March 2022, the authors of these completed but unpublished obstetrical randomized clinical trials were contacted and invited to respond to a survey examining perceptions of barriers to publication, responses of which were collected and presented as counts and percentages. RESULTS: Of the 647 obstetrical randomized clinical trials marked as completed on ClinicalTrials.gov, 378 (58%) were published, and 269 (42%) were unpublished. Unpublished trials were more likely to have an enrollment size of <50 participants (14.5% published vs 25.3% unpublished; P<.001) and less likely to be conducted at multiple sites (25.4% published vs 17.5% unpublished; P<.02). The main barriers to publication reported in the survey by authors whose trials were not published included lack of time (30%), change in employment or completion of training (25%), and results that were not of statistical significance (15%). CONCLUSION: Among the obstetrical randomized clinical trials registered and marked as completed on ClinicalTrials.gov, more than 40% were unpublished. Unpublished trials were more likely to be smaller studies, conducted by researchers who reported experiencing a lack of time as the most common barrier to study publication.

Sickle Cell Crises in Pregnancy: Fetal and Neonatal Implications.

Sickle cell disease (SCD) is the most common inherited condition worldwide. In the United States, SCD affects 100,000 births every year, mostly persons of African descent. In SCD, red blood cells assume a sickle shape when deoxygenated. This leads to the occlusion of small blood vessels and decreased oxygenated blood flow, resulting in ischemic and thrombotic injury to various organs, which further leads to organ dysfunction. In pregnancy, patients with SCD are at an increased risk of vaso-occlusive crises, which further increases the risks of maternal, fetal, and neonatal morbidity and mortality.

Utilizing International Classification of Diseases Codes to Identify Shoulder Dystocia and Neonatal Brachial Plexus Injury.

BACKGROUND: The utilization of International Classification of Diseases, Ninth or Tenth Revision, (ICD-9/10) coding to identify the incidence of disease is frequently performed in medical research. This study attempts to assess the validity of using ICD-9/10 codes to identify patients with shoulder dystocia (SD) with concurrent neonatal brachial plexus palsy (NBPP). METHODS: This retrospective cohort study examined patients evaluated at the University of Michigan Brachial Plexus and Peripheral Nerve Program (UM-BP/PN) from 2004 to 2018. We reported the percentage of patients with reported NBPP ICD-9/10 and SD ICD-9/10 discharged at birth who were later diagnosed with NBPP by a specialty clinic by interdisciplinary faculty and staff utilizing physical evaluations and ancillary testing such as such as electrodiagnostics and imaging. The relationship of reported NBPP ICD-9/10, SD ICD-9/10, extent of NBPP nerve involvement, and NBPP persistence at age two years were examined via chi-square or Fischer exact test. RESULTS: Of the 51 mother-infant dyads with complete birth discharge records evaluated at the UM-BP/PN, 26 (51%) were discharged without an ICD-9/10 code documenting NBPP; of these 26 patients, only four had ICD-9/10 documentation of SD at discharge, which left 22 patients with no ICD-9/10 code documentation of either SD or NBPP (43%). Patients with pan-plexopathy were more likely to be discharged with an NBBP ICD-9/10 code than those infants with upper nerve involvement (77% vs 39%, P < 0.02). CONCLUSION: Use of ICD-9/10 codes for the identification of NBPP appears to undercount the true incidence. This underestimation is more pronounced for milder forms of NBPP.

Effect of a Multimedia Educational Tool on Contraception Use 1 Year Postpartum.

FUNDING SOURCE: Supported in part by a research grant from Investigator-Initiated Studies program of Organon. The opinions expressed in this paper are those of the authors and do not necessarily represent Organon. CLINICAL TRIAL REGISTRAION: ClinicalTrials.gov , NCT04291040.

Factors associated with exclusive formula feeding among individuals with low-risk pregnancies in the United States.

BACKGROUND: Better understanding of the factors associated with formula feeding during the hospital stay can help in identifying potential lactation problems and promote early intervention. Our aim was to ascertain factors associated with exclusive formula feeding in newborns of low-risk pregnancies. METHODS: A population-based, retrospective study using the United States vital statistics datasets (2014-2018) evaluating low-risk pregnancies with a nonanomalous singleton delivery from 37 to 41 weeks. People with hypertensive disorders, or diabetes, were excluded. Primary outcome was newborn feeding (breast vs exclusive formula feeding) during hospital stay. Adjusted relative risks (aRRs) with 95% confidence intervals (CI) were calculated. RESULTS: Of the 19 623 195 live births during the study period, 11 605 242 (59.1%) met inclusion criteria and among them, 1 929 526 (16.6%) were formula fed. Factors associated with formula feeding included: age < 20 years (aRR 1.31 [95% CI 1.31-1.32]), non-Hispanic Black (1.42, 1.41-1.42), high school education (1.69, 1.69-1.70) or less than high school education (1.94, 1.93, 1.95), Medicaid insurance (1.52, 1.51, 1.52), body mass index (BMI) < 18.5 (1.10, 1.09-1.10), BMI 25-29.9 (1.09, 1.09-1.09), BMI 30-34.9 (1.19, 1.19-1.20), BMI 35-39.9 (1.31, 1.30-1.31), BMI ≥ 40 (1.43, 1.42-1.44), multiparity (1.29, 1.29-1.30), lack of prenatal care (1.49, 1.48-1.50), smoking (1.75, 1.74-1.75), and gestational age (ranged from 37 weeks [1.44, 1.43-1.45] to 40 weeks [1.11, 1.11-1.12]). CONCLUSIONS: Using a large cohort of low-risk pregnancies, we identified several modifiable factors associated with newborn feeding (eg, prepregnancy BMI, access to prenatal care, and smoking cessation). Improving the breast feeding initiation rate should be a priority in our current practice to ensure equitable care for all neonates.

Racial and Ethnic Disparities among Pregnancies with Chronic Hypertension and Adverse Outcomes.

OBJECTIVE: We aimed to ascertain whether the risk of adverse pregnancy outcomes in the United States among individuals with chronic hypertension differed by maternal race and ethnicity and to assess the temporal trend. STUDY DESIGN: Population-based retrospective study using the U.S. Vital Statistics datasets evaluated pregnancies with chronic hypertension, singleton live births that delivered at 24 to 41 weeks. The coprimary outcomes were a composite maternal adverse outcome (preeclampsia, primary cesarean delivery, intensive care unit admission, blood transfusion, uterine rupture, or unplanned hysterectomy) and a composite neonatal adverse outcome (preterm birth, small for gestational age, Apgar's score <5 at 5 minutes, assisted ventilation> 6 hours, seizure, or death). Multivariable Poisson regression models were used to estimate adjusted relative risks (aRRs) and 95% confidence intervals (CIs). RESULTS: Between 2014 and 2019, the rate of chronic hypertension in pregnancy increased from 1.6 to 2.2%. After multivariable adjustment, an increased risk for the composite maternal adverse outcome was found in Black (aRR = 1.10, 95% CI = 1.09-1.11), Hispanic (aRR = 1.04, 95% CI = 1.02-1.05), and Asian/Pacific Islander (aRR = 1.07, 95% CI = 1.05-1.10), compared with White individuals. Compared with White individuals, the risk of the composite neonatal adverse outcome was higher in Black (aRR = 1.39, 95% CI = 1.37-1.41), Hispanic (aRR = 1.15, 95% CI = 1.13-1.16), Asian/Pacific Islander (aRR = 1.34, 95% CI = 1.31-1.37), and American Indian (aRR = 1.12, 95% CI = 1.07-1.17). The racial and ethnic disparity remained unchanged during the study period. CONCLUSION: We found a racial and ethnic disparity with maternal and neonatal adverse outcomes in pregnancies with chronic hypertension that remained unchanged throughout the study period. KEY POINTS: · Between 2014 and 2019, the rate of chronic hypertension in pregnancy increased.. · Among people with chronic hypertension, there are racial and ethnic disparities in adverse outcomes.. · Black, Hispanic, and Asian/Pacific Islander have a higher risk of the adverse neonatal outcomes..

Factors associated with long-acting reversible contraception usage: Results from the National Survey of Family Growth.

OBJECTIVE: The authors aimed to identify factors associated with long-acting reversible contraception (LARC) usage. METHODS: The current cross-sectional study used data from the National Survey of Family Growth from 2011 to 2019. Respondents aged 15 to 44 years were included. Those with previous sterilization, infertility, or pregnant were excluded. The outcome evaluated was use of a LARC. RESULTS: Of 61 543 814 women, 44 287 911 (72.0%) met inclusion criteria. The rate of LARC use was 13.4%. Factors associated with an increased likelihood of LARC usage were married/living with a partner (adjusted relative risk [aRR], 1.18 [95% CI, 1.02-1.37]), perceived good health (aRR, 1.44 [95% CI, 1.13-1.84]), year of survey 2017 to 2019 (aRR, 1.53, [95% CI, 1.28-1.83]), one or two past pregnancies (aRR, 1.62 [95% CI, 1.24-2.12]) or three or more past pregnancies (aRR, 1.67 [95% CI, 1.22-2.28]), age at first live birth <20 years (aRR, 1.58 [95% CI, 1.20-2.08]) or 20 to 24 years (aRR, 1.45 [95% CI, 1.13-1.87]), age at onset of sexual activity 13-19 years (aRR, 1.50 [95% CI, 1.26-1.78]), and a 0- to 5-month period of nonintercourse in the past year (aRR, 1.63 [95% CI, 1.40-1.90]). Factors associated with decreased LARC usage were age ≥ 35 years (aRR, 0.74 [95% CI, 0.65-0.85]), being non-Hispanic Black (aRR, 0.75 [95% CI, 0.62-0.89]) or non-Hispanic other (aRR, 0.72 [95% CI, 0.59-0.88]), intending to have children (aRR, 0.65 [95% CI, 0.57-0.74]), and never being sexually active (aRR, 0.10 [95% CI, 0.06-0.16]). CONCLUSIONS: Using a nationally representative sample of women in the United States, the authors identified modifiable factors associated with LARC use. Results may be used to plan interventional trials to increase LARC usage.

The association between gestational age and maternal adverse outcomes in patients undergoing trial of labor after cesarean.

BACKGROUND: Although successful trial of labor after cesarean (TOLAC) resulting in vaginal birth after cesarean (VBAC) can lead to improved maternal and neonatal outcomes, an unsuccessful TOLAC is associated with increased risk of uterine rupture, higher blood loss, and increased risk of infection. Data remain limited in terms of whether differences in gestational age of patients who attempt TOLAC affect maternal morbidity. Out objective was to examine the association between gestational age and maternal adverse outcomes in women undergoing trial of labor after cesarean. METHODS: This population-based cross-sectional study used birth data from the U.S. National Vital Statistics from 2014 to 2018. Women with liveborn singleton gestation who underwent TOLAC at 23 - 41 weeks' gestation were included in the analytic population. The primary outcome was a composite of maternal adverse outcomes: admission to the intensive care unit, blood transfusion, uterine rupture, or unplanned hysterectomy. Secondary outcomes were individual measures within the primary composite outcome. Outcomes were compared between patients who underwent TOLAC at term (37-41 weeks gestational age) and those who underwent TOLAC at preterm (23-36 weeks gestational age). Multivariable analyses adjusted for demographic and obstetric differences between the two groups. RESULTS: 455,284 patients met inclusion criteria for the study; 39,589 (8.7%) were at a preterm gestational age (GA) and 415,695 (91.3%) were at a term GA. The overall composite maternal adverse outcome was significantly higher for patients undergoing TOLAC at preterm GA (12.0 per 1,000 live births) compared to term GA (8.0 per 1,000 live births; aRR1.42; 95% CI 1.29-1.56). Among individual conditions within the primary composite outcome, preterm gestational age was associated with increased risk of admission to the intensive care unit, blood transfusion, and unplanned hysterectomy. CONCLUSIONS: In patients who underwent TOLAC, preterm gestational age was associated with increased risk of adverse maternal outcomes.

Temporal Changes in Counseling for and Use of Emergency Contraception.

Our objective was to evaluate changes in the prevalence of emergency contraception counseling and use after policy changes in the United States between 2011 and 2019. This was a serial cross-sectional study using the National Survey of Family Growth data set from two survey windows: 2011-2013 (4,177 women) and 2017-2019 (4,477 women). The incidence of emergency contraception counseling in the prior year did not differ between the 2011-2013 and 2017-2019 survey windows (3.3% vs 2.5%; adjusted odds ratio [aOR] 0.73, 95% CI 0.51-1.05). There was a significant increase in ever use of emergency contraception between the 2011-2013 and 2017-2019 survey windows (19.0% vs 26.1%; aOR 1.44, 95% CI 1.22-1.72). This suggests that changes facilitating access to care may have a larger effect on emergency contraception access and uptake than health care professional counseling.

Racial and Ethnic Disparities in Primary Cesarean Birth and Adverse Outcomes Among Low-Risk Nulliparous People.

OBJECTIVE: To compare trend of primary cesarean delivery rate and composite neonatal and maternal adverse outcomes in low-risk pregnancies among racial and ethnic groups: non-Hispanic White, non-Hispanic Black, and Hispanic. METHODS: This population-based cohort study used U.S. vital statistics data (2015-2019) to evaluate low-risk, nulliparous patients with nonanomalous singletons who labored and delivered at 37-41 weeks of gestation. The primary outcome was the primary cesarean delivery rate. Secondary outcomes included composite neonatal adverse outcome (Apgar score less than 5 at 5 minutes, assisted ventilation for more than 6 hours, seizure, or death), and composite maternal adverse outcome (intensive care unit admission, blood transfusion, uterine rupture, or unplanned hysterectomy), as well as infant death. Multivariable Poisson regression models were used to estimate adjusted relative risks (aRR) and 95% CIs. RESULTS: Among 4.3 million births, 60.6% identified as non-Hispanic White, 14.6% identified as non-Hispanic Black, and 24.8% identified as Hispanic. The rate of primary cesarean delivery was 18.5% (n=804,155). An increased risk for cesarean delivery was found in non-Hispanic Black (21.7%, aRR 1.24, 95% CI 1.23-1.25) and Hispanic (17.3%, aRR 1.09, 95% CI 1.09-1.10) individuals, compared with non-Hispanic White individuals (18.1%) after multivariable adjustment. There was an upward trend in the rate of primary cesarean delivery in all racial and ethnic groups ( P for linear trend<0.001 for all groups). However, the racial and ethnic disparity in the rate of primary cesarean delivery remained stable during the study period. The composite neonatal adverse outcome was lower in Hispanic individuals in all newborns (10.7 vs 8.3 per 1,000 live births, aRR 0.74, 95% CI 0.72-0.75), and in newborns delivered by primary cesarean delivery (18.5 vs 15.0 per 1,000 live births, aRR 0.73, 95% CI 0.70-0.76), compared with non-Hispanic White individuals. CONCLUSION: Using a nationally representative sample in the United States, we found racial and ethnic disparities in the primary cesarean delivery rate in low-risk nulliparous patients, which persisted throughout the study period.

Preterm cesarean delivery for nonreassuring fetal heart rate tracing: Risk factors and predictability of adverse outcomes.

OBJECTIVE: To compare adverse outcomes among preterm births that underwent cesarean delivery (CD) for non-reassuring fetal heart rate tracing (NRFHT) versus those that did not. STUDY DESIGN: Consortium on Safe Labor Database was utilized for this secondary analysis. Inclusion criteria were non-anomalous, singleton at 23.0 to 36.6 weeks who labored for at least 2 h. Composite adverse neonatal outcomes included any of the following intraventricular hemorrhage grade III or IV, seizures, mechanical ventilation, sepsis, necrotizing enterocolitis 2 or 3, or neonatal death. Composite adverse maternal outcomes included any of the following postpartum hemorrhage, endometritis, blood transfusion, chorioamnionitis, admission to intensive care unit, thromboembolism, or death. RESULTS: Of 228,438 births, 29,592 (13.0%) delivered preterm, and 16,679 (56.4%) labored for at least 2 hrs. CD for NR FHRT was done in 1,220 (7.3%). The rate of composite adverse neonatal outcome was different among those that had CD for NR FHRT (26.7%) versus those that did not (16.6%; aRR 1.59, 95% CI 1.43-1.76). Composite adverse maternal outcomes did not differ between the groups. The area under the curve for risk factors to identify composite adverse neonatal outcome was 0.81, and for composite adverse maternal outcomes, 0.64. CONCLUSIONS: Subsequent to CD for NR FHRT, composite adverse neonatal outcome is 59% higher among preterm births when compared to delivery with reassuring tracing; composite adverse maternal outcomes did not differ between the groups.

Maternal Education Level Among People with Diabetes and Associated Adverse Outcomes.

OBJECTIVE: The aim of the study is to determine the relation between education and adverse outcomes in individuals with pregestational or gestational diabetes. STUDY DESIGN: This population-based cohort study, using the U.S. vital statistics datasets, evaluated individuals with pregestational or gestational diabetes who delivered between 2016 and 2019. The primary outcome was composite neonatal adverse outcome including any of the following: large for gestational age (LGA), Apgar's score 6 hours, neonatal seizure, or neonatal death. The secondary outcome was composite maternal adverse outcomes including any of the following: admission to intensive care unit, transfusion, uterine rupture, or unplanned hysterectomy. Multivariable analysis was used to estimate adjusted relative risks (aRR) and 95% confidence intervals (CIs). RESULTS: Of 15,390,962 live births in the United States, 858,934 (5.6%) were eligible for this analysis. Compared with individuals with a college education and above, the risk of composite neonatal adverse outcome was higher in individuals with some college (aRR = 1.08, 95% CI = 1.07-1.09), high school (aRR = 1.06, 95% CI = 1.04-1.07), and less than high school (aRR = 1.05, 95% CI = 1.03-1.07) education. The components of composite neonatal adverse outcome that differed significantly between the groups were LGA, Apgar's score 6 hours. Infant death differed when stratified by education level. An increased risk of composite maternal adverse outcome was also found with a lower level of education. CONCLUSION: Among individuals with diabetes, lower education was associated with a modestly higher risk of adverse neonatal and maternal outcomes. KEY POINTS: · Education levels were associated with adverse outcomes among individuals with diabetes.. · Lower education is associated with multiple neonatal complications, including infant death.. · Individuals with varying levels of education are at higher risk for adverse maternal outcomes..

Association Between Low-Dose Aspirin and Development of Gestational Diabetes: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the association between the use of low-dose aspirin for preeclampsia prophylaxis and risks of gestational diabetes (primary outcome), neonatal hypoglycemia, macrosomia, large for gestational age, birth trauma, and shoulder dystocia (secondary outcomes). DATA SOURCES: We searched Ovid MEDLINE, Embase, CINAHL, and Cochrane/CENTRAL for studies published between January 1, 1989, and April 24, 2021. STUDY SELECTION: Randomized controlled trials (RCTs) or cohort studies of any size conducted in any setting were included. DATA EXTRACTION AND SYNTHESIS: We assessed risk of bias using the Cochrane Risk of Bias tool 2.0 (for RCTs) and the Newcastle-Ottawa Scale (for cohort studies). We meta-analyzed relative risks (RRs) using random-effects models. CONCLUSIONS: Our search retrieved 4441 records, of which 9 studies (6 RCTs with 1932 patients and 3 cohort studies with 313 837 patients) met inclusion criteria. We rated only 4 of the 6 RCTs and 1 of the 3 cohort studies at low risk of bias. Low-dose aspirin in pregnancy for preeclampsia prophylaxis was not associated with a greater risk of gestational diabetes (RR 1.18; 95% confidence interval 0.80-1.74). No studies reported data for the secondary outcomes. In summary, the use of low-dose aspirin does not appear associated with risk of gestational diabetes. The poor quality and small number of studies limit the interpretation of these results.

Educational Multimedia Tool Compared With Routine Care for the Uptake of Postpartum Long-Acting Reversible Contraception in Individuals With High-Risk Pregnancies: A Randomized Controlled Trial.

OBJECTIVE: To assess whether an intervention with a multimedia educational tool, compared with routine care, would increase the use of long-acting reversible contraceptives (LARC) at 12 weeks postpartum in individuals with high-risk pregnancies. METHODS: In this single-center randomized trial, we assigned individuals aged 13-50 years with high-risk pregnancies to either a multimedia educational tool or routine care. Participants were included during pregnancy through postpartum day 1. Those randomized to the multimedia educational tool (MET) group were provided a tablet with the preloaded 3-5-minute multimedia presentation (https://prezi.com/view/jpFrXaPnnxuqRkcI3A4a/), which was viewed without the presence of research staff and resent by secure email every 4 weeks if undelivered. The primary outcome was uptake of LARC (implant or intrauterine device) within 12 weeks of delivery. The secondary outcomes included overall use of any method of contraception and composite maternal and neonatal adverse outcomes. A priori estimates indicated that 380 participants were needed to detect a 40% difference in use of LARC (baseline 40%; alpha=0.05, power=0.8, assumed loss to follow-up 20%). Relative risk (RR) and number needed to treat (NNT), along with 95% CIs, were calculated. RESULTS: From July 2020 through December 2020, 536 persons were screened and 380 randomized as follows: 190 for the multimedia educational tool and 190 for routine care. Demographic characteristics were similar between groups. The primary outcome-available for more than 90% of participants-was higher in the MET group (32.4%) than in the routine care (RC) group (20.9%) (RR 1.55; 95% CI 1.09-2.21; NNT nine, with 95% CI 5-42). Overall use of contraception was also higher in the MET group than in the RC group (RR 1.16; 95% CI 1.03-1.32). CONCLUSION: Among individuals with high-risk pregnancies, compared with routine care, use of a multimedia-based educational tool increased the uptake of postpartum LARC by 55%. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT04291040. FUNDING SOURCE: Funded in part by Investigator-Initiated studies of Organon.

Association between route of delivery and maternal adverse outcomes in pregnancies complicated by preterm birth.

INTRODUCTION: To determine the impact of route of delivery on maternal outcomes among individuals who deliver preterm (before 37 weeks). MATERIALS AND METHODS: This was a population-based retrospective cohort study using the U.S. vital statistics datasets on Period Linked Birth-Infant Death Data from 2014 to 2018. The study population was restricted to live births from women with non-anomalous singletons who delivered at 24-36 weeks of gestation. The main explanatory variable for this study was route of delivery, which was categorized as: (i) vaginal delivery, (ii) cesarean delivery with labor, and (iii) cesarean delivery without labor. The primary outcome was composite maternal adverse outcome, which encompassed any of the following: admission to the intensive care unit, maternal blood transfusion, uterine rupture, or unplanned hysterectomy. The results were presented as adjusted relative risk (aRR) with 95% confidence interval (CI). RESULTS: Over the study period 1,440,510 live births met the inclusion criteria, and the overall composite maternal adverse outcome was 14.38 per 1,000 live births. After multivariable adjustment, compared to women who underwent a vaginal delivery, the risk of composite maternal adverse outcome was higher in women who had a cesarean delivery with labor (aRR 3.70; 95% CI 3.52-3.90) and those who had a cesarean delivery without labor (aRR 4.79; 95% CI 4.59-4.98). CONCLUSION: With preterm birth, cesarean delivery without labor has higher rate of composite maternal morbidity than cesarean during labor or vaginal delivery.