Number and quality of randomized controlled trials in obstetrics published in the top general medical and obstetrics and gynecology journals

BACKGROUND

There has been an increasing number of randomized controlled trials published in obstetrics and maternal-fetal medicine to reduce biases of treatment effect and to provide insights on the cause-effect of the relationship between treatment and outcomes.

OBJECTIVE

This study aimed to identify obstetrical randomized controlled trials published in top weekly general medical journals and monthly obstetrics and gynecology journals, to assess their quality in reporting and identify factors associated with publication in different journals.

STUDY DESIGN

The 4 weekly medical journals with the highest 2019 impact factor (New England Journal of Medicine, The Lancet, The Journal of the American Medical Association, and British Medical Journal), the top 4 monthly obstetrics and gynecology journals with obstetrics-related research (American Journal of Obstetrics & Gynecology, Ultrasound in Obstetrics & Gynecology, Obstetrics & Gynecology, and the British Journal of Obstetrics and Gynaecology), and the American Journal of Obstetrics & Gynecology Maternal-Fetal Medicine were searched for obstetrical randomized controlled trials in the years 2018 to 2020. The primary outcome was the number of obstetrical randomized controlled trials published in the obstetrics and gynecology journals vs the weekly medical journals and the percentage of trials published, overall and per journal. The secondary outcomes included the proportion of positive vs negative trials overall and per journal and the assessment of the study characteristics of published trials, including quality assessment criteria.

RESULTS

Of the 4024 original research articles published in the 9 journals during the 3-year study period, 1221 (30.3%) were randomized controlled trials, with 137 (11.2%) randomized controlled trials being in obstetrics (46 in 2018, 47 in 2019, and 44 studies in 2020). Furthermore, 33 (24.1%) were published in weekly medical journals, and 104 (75.9%) were published in obstetrics and gynecology journals. The percentage of obstetrical randomized controlled trials published ranged from 1.5% to 9.6% per journal. Overall, 34.3% of obstetrical trials were statistically significant or "positive" for the primary outcome. Notably, 24.8% of the trials were retrospectively registered after the enrollment of the first study patient. Trials published in the 4 weekly medical journals enrolled significantly more patients (1801 vs 180; P<.001), received more often funding from the federal government (78.8% vs 35.6%; P<.001), and were more likely to be multicenter (90.9% vs 42.3%; P<.001), non-United States based (69.7% vs 49.0%; P=.03), and double blinded (45.5% vs 18.3%; P=.003) than trials published in the obstetrics and gynecology journals. There was no difference in study type (noninferiority vs superiority) and trial quality characteristics, including pretrial registration, ethics approval statement, informed consent statement, and adherence to the Consolidated Standards of Reporting Trials guidelines statement between studies published in weekly medical journals and studies published in obstetrics and gynecology journals.

CONCLUSION

Approximately 45 trials in obstetrics are being published every year in the highest impact journals, with one-fourth being in the weekly medical journals and the remainder in the obstetrics and gynecology journals. Only about a third of published obstetrical trials are positive. Trials published in weekly medical journals are larger, more likely to be funded by the government, multicenter, international, and double blinded. Quality metrics are similar between weekly medical journals and obstetrics and gynecology journals.

Maternal Sepsis: A Review of National and International Guidelines

OBJECTIVE

 Sepsis is a life-threatening syndrome caused by the body's response to infection. The Global Maternal Sepsis Study (GLOSS) suggests sepsis plays a larger role in maternal morbidity and mortality than previously thought. We therefore sought to compare national and international guidelines for maternal sepsis to determine their consistency with each other and the Third International Consensus for Sepsis and Septic Shock (SEPSIS-3).

STUDY DESIGN

 Using Cochrane Database of Systematic Reviews, PubMed, Google Scholar, and organization Web sites, we identified seven guidelines on maternal sepsis in the English language-The American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine, Royal Australian and New Zealand College of Obstetricians and Gynaecologists, Society of Obstetric Medicine of Australia and New Zealand, Royal College of Obstetricians and Gynaecologists, Royal College of Physicians of Ireland Institute of Obstetricians and Gynaecologists, and World Health Organization. Guidelines were reviewed to ascertain the commonality and variation, if any, in definitions of maternal sepsis, tools and criteria utilized for diagnosis, obstetric warning systems used, as well as evaluation and management of maternal sepsis. These variables were also compared with SEPSIS-3.

RESULTS

 All guidelines provided definitions consistent with a version of the SEPSIS, although the specific version utilized were varied. Clinical variables and tools employed for diagnosis of maternal sepsis were also varied. Evaluation and management of maternal sepsis and septic shock were similar.

CONCLUSION

 In conclusion, national and international maternal sepsis guidelines were incongruent with each other and SEPSIS-3 in diagnostic criteria and tools but similar in evaluation and management recommendations.

KEY POINTS

· Definitions for maternal sepsis and septic shock are varied.. · Maternal sepsis guidelines differ in proposed criteria and tools.. · Maternal sepsis guidelines have similar management recommendations..

Association between time of delivery and composite adverse outcomes in pregnancies complicated by hypertensive disorders

INTRODUCTION

A potential manner to lower the morbidity with the hypertensive disoreders of pregancy is to explore the time of day of delivery.

OBJECTIVE

To compare composite neonatal adverse outcomes among term women with hypertensive disorders.

METHODS

This population-based cohort study used the U.S. vital statistics dataset from 2013 to 2017. Time of delivery was categorized into three shifts. The primary outcome was composite neonatal adverse outcome..

RESULTS

Compared to neonates delivered at the first shift, the risk of composite neonatal adverse outcome was higher at the third shift (aRR = 1.19, 95% CI = 1.13-1.25).

CONCLUSION

the risk of composite neonatal adverse outcome is higher if the delivery occurs at the third (23:00-7:00) shift.

Amniotic Fluid Volume Assessment: Eight Lessons Learned

Actual AFV can be determined by a dye-dilution technique or be directly measured at cesarean. This allows investigators to correlate estimated and actual AFVs. Lessons learned by assessing the relationship of estimated to actual AFVs. 1) Ultrasound estimates normal actual AFVs well, but abnormal AFVs poorly. 2) Quantile regression is a better statistical methodology to create a normal AFV curve across pregnancy. 3) There is no difference in the accuracy of the subjective (visualization without measurements) compared with the objective (visualization with measurements) technique in identifying normal and abnormal AFVs. 4) Color Doppler use leads to the over-diagnosis of oligohydramnios. 5) Intravenous hydration increases actual AFVs. 6) The estimation of AFV can be done with the transducer held perpendicular to the floor or perpendicular to the uterine contour. 7) The single deepest pocket should be used for identifying low AFVs. 8) The AFI should be used for identifying high AFVs.

Maternal and Neonatal Outcomes in Nulliparous Participants Undergoing Labor Induction by Cervical Ripening Method

OBJECTIVE

 This study aimed to evaluate maternal and neonatal outcomes by method of cervical ripening for labor induction among low-risk nulliparous individuals.

STUDY DESIGN

 This is a secondary analysis of a multicenter randomized trial of labor induction at 39 weeks versus expectant management in low-risk nulliparous participants. Participants undergoing cervical ripening for labor induction in either group were included. Participants were excluded for preripening membrane rupture, abruption, chorioamnionitis, fetal demise, or cervical dilation ≥3.5 cm. Cervical ripening was defined by the initial method used: prostaglandin only (PGE; referent), Foley with concurrent prostaglandin (Foley-PGE), Foley only (Foley), and Foley with concurrent oxytocin (Foley-oxytocin). Coprimary outcomes were adverse maternal and neonatal composites. Secondary outcomes included cesarean delivery and length of labor and delivery (L&D) stay. Multivariable analysis was used to adjust for patient characteristics.

RESULTS

 Of 6,106 participants included in the trial, 2,376 (38.9%) met criteria for this analysis. Of these, 1,247 (52.4%) had cervical ripening with PGE, 290 (12.2%) had Foley-PGE, 385 (16.2%) had Foley, and 454 (19.1%) had Foley-oxytocin. The maternal composite outcome was similar among participants who received Foley-PGE (24.1%, adjusted relative risk [aRR] = 1.21, 95% confidence interval [CI]: 0.96-1.52), Foley (21.3%, aRR = 1.16, 95% CI: 0.92-1.45), or Foley-oxytocin (19.4%, aRR = 1.04, 95% CI: 0.83-1.29), compared with PGE (19.7%). The neonatal composite outcome was less frequent in participants who received the Foley-PGE (2.4%, aRR = 0.35, 95% CI: 0.16-0.75) or Foley (3.6%, aRR = 0.51, 95% CI: 0.29-0.89) but did not reach statistical significance for participants who received Foley-oxytocin (4.6%, aRR = 0.63, 95% CI: 0.40-1.01) compared with PGE only (6.8%). Participants who received Foley-PGE or Foley-oxytocin had a shorter L&D stay (adjusted mean difference = -1.97 hours, 95% CI: -3.45 to -0.49 and -5.92 hours, 95% CI: -7.07 to -4.77, respectively), compared with PGE.

CONCLUSION

 In term low-risk nulliparous participants, Foley alone or concurrent with PGE is associated with a lower risk of adverse neonatal outcomes than with PGE alone. Length of L&D stay was the shortest with concurrent Foley-oxytocin.

KEY POINTS

· Adverse maternal outcomes are similar among different methods of cervical ripening in low-risk women.. · Adverse neonatal outcomes are less frequent with use of Foley alone or in combination with PGE.. · The use of Foley alone, or in combination with other agents, appears to be beneficial..

Type 2 diabetes and neonatal hypoglycemia: role of route of delivery and insulin infusion

OBJECTIVE

To compare the rate of neonatal hypoglycemia among newborns delivered by individuals with Type 2 diabetes mellitus (T2DM) in two clinical scenarios: who attempted vaginal delivery vs. had a planned cesarean delivery (CD); who had intrapartum insulin infusion vs. who did not.

METHODS

This was a retrospective cohort study of individuals with insulin-treated T2DM who had non-anomalous singleton pregnancy and delivered at a single tertiary center (March 2012 and May 2018). Individuals with chronic renal failure, proliferative retinopathy, or major congenital anomalies were excluded. The primary outcome was neonatal hypoglycemia (blood glucose < 40 mg/dl <24 h of age or < 50 mg/dl >24 h of age). Secondary outcomes included neonatal outcomes. Multivariable Poisson regression models with robust error variance were used to examine the association between groups and the primary outcome. Adjusted relative risk (aRR) and 95% confidence intervals (CI) were calculated.

RESULTS

Of 233 individuals with T2DM, 215 (92.2%) met the inclusion criteria, of whom 95 (44%) attempted vaginal delivery and 120 (56%) had a planned CD. Individuals who labored had a higher gestational age at delivery (36.6 vs. 35.8 weeks, p = .005), and higher blood glucose levels upon admission (125 vs 103, p < .001) compared to those with a planned CD. After adjustment for potential confounders, there was no difference in risk of neonatal hypoglycemia between the groups (41.2 vs 44.1%, aRR 1.05, 95% CI = 0.75-1.45). Among those who attempted vaginal delivery, 34 (35.8%) required insulin infusion. There was no difference in the risk of neonatal hypoglycemia (aRR = 0.79, 95% CI = 0.45-1.37) between newborns delivered by individuals who required insulin infusion and those who did not.

CONCLUSION

Over 40% of newborns delivered by individuals with insulin-dependent T2DM had hypoglycemia; however, there was no significant difference in the risk of hypoglycemia, irrespective of the route of delivery and the use of insulin infusion.

Maternal and Neonatal Outcomes Associated with Amniotomy among Nulliparous Women Undergoing Labor Induction at Term

OBJECTIVE

The aim of the study is to evaluate the association between amniotomy at various time points during labor induction and maternal and neonatal outcomes among term, nulliparous women.

STUDY DESIGN

Secondary analysis of a randomized trial of term labor induction versus expectant management in low-risk, nulliparous women (2014-2017) was conducted. Women met inclusion criteria if they underwent induction ≥38 weeks' gestation using oxytocin with documented time and type of membrane rupture. Women with antepartum stillbirth or fetal anomaly were excluded. The primary outcome was cesarean delivery. Secondary outcomes included maternal and neonatal complications. Maternal and neonatal outcomes were compared among women with amniotomy versus women with intact membranes and no amniotomy at six 2-hour time intervals: before oxytocin initiation, 0 to <2 hours after oxytocin, 2 to <4 hours after, 4 to <6 hours after, 6 to <8 hours after, and 8 to <10 hours after. Multivariable logistic regression adjusted for maternal age, body mass index, race/ethnicity, modified Bishop score on admission, treatment group, and hospital (as a random effect).

RESULTS

Of 6,106 women in the parent trial, 2,854 (46.7%) women met inclusion criteria. Of these 2,340 (82.0%) underwent amniotomy, and majority of the women had amniotomy performed between 2 and <6 hours after oxytocin. Cesarean delivery was less frequent among women with amniotomy 6 to <8 hours after oxytocin compared with women without amniotomy (21.9 vs. 29.7%; adjusted odds ratio 0.61, 95% confidence interval 0.42-0.89). Amniotomy at time intervals ≥4 hours after oxytocin was associated with lower odds of labor duration >24 hours. Amniotomy at time intervals ≥2 hours and <8 hours after oxytocin was associated with lower odds of maternal hospitalization >3 days. Amniotomy was not associated with postpartum or neonatal complications.

CONCLUSION

Among a contemporary cohort of nulliparous women undergoing term labor induction, amniotomy was associated with either lower or similar odds of cesarean delivery and other adverse outcomes, compared with no amniotomy.

Transcervical Foley Balloon Plus Vaginal Misoprostol versus Vaginal Misoprostol Alone for Cervical Ripening in Nulliparous Obese Women: A Multicenter, Randomized, Comparative-Effectiveness Trial

OBJECTIVE

Nulliparous obese women are at increased risk of labor induction and cesarean delivery (CD). We sought to determine whether the combination of a transvaginal Foley balloon plus misoprostol prostaglandin E1 (PGE1) is superior to misoprostol alone in reducing the risk for CD.

STUDY DESIGN

We undertook a multicenter, open-label, comparative-effectiveness randomized clinical trial of nulliparous obese women with unfavorable cervix (Bishop's score ≤ 6) undergoing labor induction from January 2016 to June 2018 at three tertiary centers. Those at <32 weeks' gestation, premature rupture of membranes, stillbirth, and major fetal anomalies were excluded. Women were randomized 1:1 to either a combination of Foley balloon and misoprostol or misoprostol alone. Once Bishop's score was >6, further management was deferred to treating physicians. Primary outcome was the rate of CD. Secondary maternal outcomes included duration of induction-to-delivery interval, occurrence of tachysystole, clinical chorioamnionitis, need for operative vaginal delivery, as well as a composite of maternal morbidity (postpartum endometritis, surgical-site infection, venous thromboembolism, need for transfusion, intensive care unit admission, and maternal death). Secondary neonatal outcomes included need for neonatal intensive care unit admission, transient tachypnea of the newborn, respiratory distress syndrome, meconium aspiration syndrome, culture-proven sepsis, neonatal seizures, and a composite of neonatal morbidity (Apgar's score ≤7 at 5 minutes, umbilical artery cord pH ≤7.10, birth injury, perinatal death). With the rate of CD rate being 53% at Children's Memorial Herman Hospital among nulliparous obese women who underwent induction of labor at ≥32 weeks and met our inclusion criteria; 250 women (125 women per group) were required to answer the study question. All analyses were by intention to treat.

RESULTS

Of the 236 women randomized, 113 (48%) were allocated to group 1 (combined Foley and PGE1) and 123 (52%) to group 2 (PGE1 alone). The rate of CD was similar between the groups (45 vs. 43%, p = 0.84, relative risk [RR]: 1.03, 95% CI: 0.75-1.42). There was no difference in the occurrence of tachysystole that resulted in fetal heart rate abnormalities between the groups (8.8 vs. 16.2%, p = 0.09, RR: 0.54, 95% CI: 0.27-1.11). The total duration of the induction-to-delivery interval was also similar between the groups (24.8 ± 13.8 vs. 24.5 ± 14.0 hours, p = 0.87) regardless of the mode of delivery. No differences were seen in the indications for CD and secondary maternal or neonatal outcomes.

CONCLUSION

In this trial of nulliparous obese women undergoing labor induction, cervical ripening with combined Foley balloon and PGE1 resulted in similar CD rates than ripening with vaginal PGE1 alone.

KEY POINTS

· Nulliparous obese women are at increased risk for cesarean delivery.. · Combined intravaginal misoprostol-Foley balloon versus misoprostol alone resulted in similar rates of cesarean delivery.. · Further research is warranted to determine the optimal cervical ripening strategy in this population..

Adverse Outcomes among Low-Risk Pregnancies at 39 to 41 Weeks: Stratified by Birth Weight Percentile

OBJECTIVE

This study aimed to assess the risk of adverse outcomes among low-risk pregnancies at 39 to 41 weeks, stratified by birth weight percentile.

STUDY DESIGN

This retrospective cohort study utilized the U.S. vital statistics datasets (2013-2017) and evaluated low-risk women with nonanomalous cephalic singleton gestations who labored and delivered at 39 to 41 weeks, regardless of ultimate mode of delivery. Newborns were categorized as small (<10th percentile), large (>90th percentile), or appropriate (10-90th percentile) for gestational ages (SGA, LGA, and AGA, respectively). The primary outcome, composite neonatal adverse outcome (CNAO), included Apgar's score <5 at 5 minutes, assisted ventilation >6 hours, seizure, or neonatal death. The secondary outcome, composite maternal adverse outcome (CMAO), included intensive care unit admission, blood transfusion, uterine rupture, or unplanned hysterectomy. Multivariable Poisson's regression was used to estimate the association (using adjusted relative risk [aRR] and 95% confidence interval [CI]).

RESULTS

Of 19.8 million live births during the study interval, approximately 8.9 million (44.9%) met the inclusion criteria, with 9.9% being SGA, 9.2% being LGA, and 80.9% being AGA. SGA newborns delivered at 40 (aRR = 1.17; 95% CI: 1.12-1.23) and at 41 weeks (aRR = 1.55; 95% CI: 1.45-1.66) had a higher risk of CNAO than at 39 weeks. Similarly, LGA newborns delivered at 40 (aRR = 1.13; 95% CI: 1.07-1.19) and 41 weeks (aRR = 1.44; 95% CI: 1.35-1.54) and AGA newborns delivered at 40 (aRR = 1.24; 95% CI: 1.21-1.26) and 41 weeks (aRR = 1.57; 95% CI: 1.53-1.61) also had a higher risk of CNAO than at 39 weeks. CMAO was also significantly higher at 40 and 41 weeks than at 39 weeks, regardless of whether the mothers delivered SGA, LGA, or AGA newborns.

CONCLUSION

Among low-risk pregnancies, the risks of composite neonatal and maternal adverse outcomes increase from 39 through 41 weeks' gestation, irrespective of whether newborns are SGA, LGA, or AGA.

A Trial of Hyperimmune Globulin to Prevent Congenital Cytomegalovirus Infection

BACKGROUND

Primary cytomegalovirus (CMV) infection during pregnancy carries a risk of congenital infection and possible severe sequelae. There is no established intervention for preventing congenital CMV infection.

METHODS

In this multicenter, double-blind trial, pregnant women with primary CMV infection diagnosed before 24 weeks' gestation were randomly assigned to receive a monthly infusion of CMV hyperimmune globulin (at a dose of 100 mg per kilogram of body weight) or matching placebo until delivery. The primary outcome was a composite of congenital CMV infection or fetal or neonatal death if CMV testing of the fetus or neonate was not performed.

RESULTS

From 2012 to 2018, a total of 206,082 pregnant women were screened for primary CMV infection before 23 weeks of gestation; of the 712 participants (0.35%) who tested positive, 399 (56%) underwent randomization. The trial was stopped early for futility. Data on the primary outcome were available for 394 participants; a primary outcome event occurred in the fetus or neonate of 46 of 203 women (22.7%) in the group that received hyperimmune globulin and of 37 of 191 women (19.4%) in the placebo group (relative risk, 1.17; 95% confidence interval [CI] 0.80 to 1.72; P = 0.42). Death occurred in 4.9% of fetuses or neonates in the hyperimmune globulin group and in 2.6% in the placebo group (relative risk, 1.88; 95% CI, 0.66 to 5.41), preterm birth occurred in 12.2% and 8.3%, respectively (relative risk, 1.47; 95% CI, 0.81 to 2.67), and birth weight below the 5th percentile occurred in 10.3% and 5.4% (relative risk, 1.92; 95% CI, 0.92 to 3.99). One participant in the hyperimmune globulin group had a severe allergic reaction to the first infusion. Participants who received hyperimmune globulin had a higher incidence of headaches and shaking chills while receiving infusions than participants who received placebo.

CONCLUSIONS

Among pregnant women, administration of CMV hyperimmune globulin starting before 24 weeks' gestation did not result in a lower incidence of a composite of congenital CMV infection or perinatal death than placebo. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Center for Advancing Translational Sciences; ClinicalTrials.gov number, NCT01376778.).

Detemir vs neutral protamine Hagedorn insulin for diabetes mellitus in pregnancy: a comparative effectiveness, randomized controlled trial

BACKGROUND

Insulin detemir, being used increasingly during pregnancy, may have pharmacologic benefits compared with neutral protamine Hagedorn.

OBJECTIVE

We evaluated the probability that compared with treatment with neutral protamine Hagedorn, treatment with insulin detemir reduces the risk for adverse neonatal outcome among individuals with type 2 or overt type 2 diabetes mellitus (gestational diabetes mellitus diagnosed at <20 weeks' gestation).

STUDY DESIGN

We performed a multiclinic randomized controlled trial (September 2018 to January 2020), which included women with singleton gestation with type 2 or overt type 2 diabetes mellitus who sought obstetrical care at ≤21 weeks' gestation. Participants were randomized to receive either insulin detemir or neutral protamine Hagedorn by a clinic-stratified scheme. The primary outcome was a composite of adverse neonatal outcomes, including shoulder dystocia, large for gestational age, neonatal intensive care unit admission, respiratory distress (defined as the need of at least 4 hours of respiratory support with supplemental oxygen, continuous positive airway pressure or ventilation at the first 24 hours of life), or hypoglycemia. The secondary neonatal outcomes included gestational age at delivery, small for gestational age, 5-minute Apgar score of <7, lowest glucose level, need for intravenous glucose, respiratory distress syndrome, need for mechanical ventilation or continuous positive airway pressure, neonatal jaundice requiring therapy, brachial plexus injury, and hospital length of stay. The secondary maternal outcomes included hypoglycemic events, hospital admission for glucose control, hypertensive disorder of pregnancy, maternal weight gain, cesarean delivery, and postpartum complications. We used the Bayesian statistics to estimate a sample size of 108 to have >75% probability of any reduction in the primary outcome, assuming 80% power and a hypothesized effect of 33% reduction with insulin detemir. All analyses were intent to treat under a Bayesian framework with neutral priors (a priori assumed a 50:50 likelihood of either intervention being better; National Clinical Trial identifier 03620890).

RESULTS

There were 108 women randomized in this trial (57 in insulin detemir and 51 in neutral protamine Hagedorn), and 103 women were available for analysis of the primary outcome (n=5 for pregnancy loss before 24 weeks' gestation). Bayesian analysis indicated an 87% posterior probability of reduced primary outcome with insulin detemir compared with neutral protamine Hagedorn (posterior adjusted relative risk, 0.88; 95% credible interval, 0.61-1.12). Bayesian analyses for secondary outcomes showed consistent findings of lower adverse maternal outcomes with the use of insulin detemir vs neutral protamine Hagedorn: for example, maternal hypoglycemic events (97% probability of benefit; posterior adjusted relative risk, 0.59; 95% credible interval, 0.29-1.08) and hypertensive disorders (88% probability of benefit; posterior adjusted relative risk, 0.81; 95% credible interval, 0.54-1.16).

CONCLUSION

In our comparative effectiveness trial involving individuals with type 2 or overt type 2 diabetes mellitus, use of insulin detemir resulted in lower rates of adverse neonatal and maternal outcomes compared with neutral protamine Hagedorn.

Apgar score at 10 minutes and adverse outcomes among low-risk pregnancies

OBJECTIVE

Among low-risk pregnancies, we ascertained the association between 10-minute Apgar score and adverse outcomes of newborn infants.

METHOD

We conducted a retrospective cohort study using the U.S. vital statistics datasets (2011-2018), which included live births from low-risk women with non-anomalous singleton gestations who delivered at 37-41 weeks. When a newborn infant had an abnormal 5-minute Apgar score (0-5), a 10-minute Apgar score was documented in the birth certificate. Apgar score at 10 min was categorized as low (0-3), moderate (4-6), and normal (7-10). The primary outcome was composite neonatal adverse outcome. The secondary outcomes were individual neonatal adverse outcomes and infant mortality. Multivariable Poisson regression analyses were used to estimate the association between 10-minute Apgar score and adverse outcomes (using adjusted relative risk [aRR] and 95% confidence intervals [CI]).

RESULTS

Of 31.5 million live births delivered (2011-2018), 111,163 (0.4%) met inclusion criteria; of them, 74.2%, 20.7%, and 5.1% had normal, moderate, and low 10-minute Apgar scores, respectively. The overall composite neonatal adverse outcome was 100.6 per 1,000 live births and the risk was significantly higher among those with a moderate (aRR 3.19; 95% CI 3.06-3.31) or low 10-minute Apgar score (aRR 6.62; 95% CI 6.34-6.91) than with a normal 10-minute Apgar score. Infant mortality also showed a similar pattern. Newborn infants with improved Apgar scores from 5 to 10 min were associated with lower risks of the composite neonatal adverse outcome, as well as infant mortality, than those with scores that remained stable.

CONCLUSION

Among low-risk pregnancies, newborn infants with a lower 10-minute Apgar score were associated with a higher risk of adverse outcomes.

Body mass index and adverse outcomes among singletons with cerclage

OBJECTIVE

To compare the neonatal and maternal adverse outcomes among women with cerclage and prepregnancy body mass index (BMI) < versus > 30 kg/m² STUDY DESIGN: This retrospective cohort study utilized the U.S. Vital Statistics Datasets from 2011-2013. Inclusion criteria were women with non-anomalous singletons, with cerclage placement, without diabetes or hypertensive disorders, and who delivered at 20-41 weeks. The primary outcome was the composite neonatal adverse outcome (Apgar score below 5 at 5 min, birth injury, assisted ventilation for more than 6 h, neonatal seizure, or neonatal death). The secondary outcomes included the composite maternal adverse outcome (admission to intensive care unit, maternal transfusion, ruptured uterus, unplanned hysterectomy, or unplanned operating room procedure), chorioamnionitis, and cesarean delivery. Multivariable Poisson regression models with robust error variance were used, while adjusting for confounders. Adjusted relative risk with 95 % confidence intervals were calculated.

RESULTS

Of the 22,466 live births that met the inclusion criteria during the study period, 6427 (28.6 %) had cerclage and prepregnancy BMI ≥ 30 kg/m². The composite neonatal adverse outcome was significantly increased (aRR 1.45; 95 % CI 1.33-1.60) among women with cerclage and BMI ≥ 30 kg/m² when compared to those with BMI < 30 kg/m². The composite maternal adverse outcome was similar (aRR 0.93; 95 % CI 0.72-1.20) among the two groups. Chorioamnionitis (aRR 1.46; 95 % CI 1.24-1.72) and cesarean delivery (aRR 1.24; 95 % CI 1.19-1.29) were higher in women with cerclage and BMI ≥ 30 kg/m².

CONCLUSION

Among pregnancies with cerclage and delivery at 20-41 weeks, the risk of the composite neonatal adverse outcome was modestly increased in newborns delivered by women with BMI ≥ 30 kg/m² than those delivered by women with BMI < 30 kg/m². No significant difference was found in the risk of the composite maternal adverse outcome.

Cesarean delivery at term for non-reassuring fetal heart rate tracing: risk factors and predictability

OBJECTIVE

To delineate risk factors for adverse outcomes among those who underwent cesarean delivery (CD) for non-reassuring fetal heart rate tracing (NRFHT) and ascertain whether neonatal or maternal morbidity can be predicted accurately.

METHODS

The Consortium on Safe Labor Database was utilized for this secondary analysis. Inclusion criteria were non-anomalous, singleton gestations between 37.0 and 41.6 weeks who underwent CD for NRFHT. Composite adverse neonatal outcomes (CANO) included Apgar <5 at 5 min, seizures, mechanical ventilation, sepsis, intraventricular hemorrhage, necrotizing enterocolitis or neonatal death. Composite adverse maternal outcomes (CAMO) included endometritis, blood transfusion, wound complication, admission to intensive care unit, thromboembolism, hysterectomy or death. Bivariable analysis and multivariable Poisson regression were used to identify risk factors independently associated with adverse outcomes. Receiver operating characteristic (ROC) curves were created to evaluate the predictive value of the models for adverse outcomes.

RESULTS

Of 228,438 births in the database, 7310 individuals (3.7%) met inclusion criteria. Among this cohort, CANO occurred 3.8% of the time. CANO was less common among people over 35 years (9.8% versus 18.4% p < .01) but was more common among those with at least high-school education (15.3% versus 11.2%; p < .01), varying by ethnicity (p < .01). CAMO occurred in 3.4% and was less common among those undergoing induction of labor (37.3% versus 49.4%; p < .01) and more common among those with clinical chorioamnionitis (8.4% versus 4.3%; p < .01). The area under the curve (AUC) for ROC curve to identify CANO was 0.63 implying a limited ability to predict neonatal adverse outcomes. The AUC for identifying women with maternal adverse outcomes was 0.69 also indicating a moderate prediction ability.

CONCLUSIONS

Among singletons between 37 and 41 weeks who labored, the rate of CD for NRFHT was about 3.7% and among them CANO occurred in 3.8%. While risk factors for adverse neonatal outcomes following CD for NRFHT are identifiable, they do not suffice to predict them.

Pregnancy Outcomes among Hispanics Stratified by Country of Origin

OBJECTIVE

This study aimed to compare the perinatal outcomes among U.S.-born and foreign-born Hispanics and Caucasians and ascertain if length of time in the US was associated with the rate of adverse outcomes.

STUDY DESIGN

Retrospective cohort analysis of gravidae enrolled in our institutional perinatal database. Women delivering a non-anomalous, singleton, at 24 weeks or more and self-identified as Caucasian or Hispanic were included. Women were stratified by country of birth and ethnicity into U.S.-born Caucasian, U.S.-born Hispanic, and U.S. foreign-born Hispanic. Composite maternal (CMM) and neonatal (CNM) morbidity was assessed.

RESULTS

Of 20,422 women, 21% were Caucasian, 15% were U.S.-born Hispanics, and 64% were U.S. foreign-born Hispanics. Compared to Caucasians, U.S.-born and foreign-born Hispanic were older, more likely to be a grand multiparous, obese and less likely to be married. Compared to Caucasians, foreign-born Hispanics had a 1.42-fold increased risk of CMM (95% CI 1.26-1.30). Paradoxically, the rate of CNM was 40% lower among neonates born to foreign-born Hispanics (95% CI 0.51-0.74). A significant direct relationship was noted between time in the USA and CMM but not CNM among foreign-born Hispanics.

CONCLUSION

Despite less favorable baseline characteristics, U.S. foreign-born Hispanics have 40% less CNM compared to both Caucasians and U.S.-born Hispanics.

Neonatal and maternal outcomes with trial of labor after two prior cesarean births: stratified by history of vaginal birth

INTRODUCTION

To determine the impact of prior vaginal birth on neonatal and maternal outcomes among individuals undergoing a trial of labor after two cesarean births.

MATERIALS AND METHODS

This was a cross-sectional study using the U.S. National Vital Statistics 2014-2018 period linked birth and infant death data. Inclusion criteria were term, cephalic, singleton pregnancies with two prior cesarean births. The primary exposure variable was a trial of labor after cesarean vs prelabor repeat cesarean birth. Cohorts were defined by the presence or absence of a prior vaginal birth. The primary outcome was a composite of adverse neonatal outcomes (Apgar score <5 at 5 min, assisted ventilation >6 h, neonatal seizures, or neonatal death within 27 days). Secondary outcomes included a maternal composite and the cesarean birth rate. Propensity score matching was used to account for baseline differences in treatment allocation within each cohort, and conditional logistic regression assessed the association between the exposure and outcomes.

RESULTS

The composite neonatal adverse outcome was significantly higher in those undergoing a trial of labor after cesarean compared to prelabor repeat cesarean birth in both individuals without a prior vaginal birth (8.2 vs 11.6 per 1000 live births, OR 1.41; 95% CI 1.12-1.70) and with a prior vaginal birth (9.6 vs 12.4 per 1000 live births, OR 1.30; 95% CI 1.08-1.57). The composite maternal adverse outcome was significantly higher among individuals without a prior vaginal birth undergoing trial of labor after cesarean (6.0 vs 9.5 per 1000 live births, OR 1.59; 95% CI 1.26-2.09), but was similar in those with a prior vaginal birth (7.9 vs 9.3 per 1000 live births, OR 1.18; 95% CI 0.97-1.46).

CONCLUSION

In individuals with two prior cesarean births, trial of labor after cesarean was associated with increased neonatal adverse outcomes when compared to prelabor repeat cesarean birth, irrespective of a history of vaginal birth. In individuals with a prior vaginal birth, the composite maternal adverse outcome was not elevated in the trial of labor cohort.

Labor induction with prostaglandin E1 versus E2: a comparison of outcomes

OBJECTIVE

To compare the peripartum outcomes when labor is induced with prostaglandins E₁ versus E₂.

METHODOLOGY

The Consortium of Safe Labor database was utilized. Women with non-anomalous singletons >24 weeks gestation undergoing induction were analyzed. The primary endpoint was a composite adverse maternal outcome with a composite adverse neonatal outcome as our secondary outcome.

RESULTS

Of the 228,438 births within the database, 8229 (10.8%) met inclusion criteria with 4703 (55.7%) receiving PGE₁, and 3741 (44.3%), PGE₂. The rate of vaginal delivery was similar between both. Composite adverse maternal outcome, was more likely among the prostaglandin E₁: 7.2% vs. 1.5% (aOR 4.20; 95% CI 3.02-5.85); similar trend observed with composite adverse neonatal outcome rates: 4.6% vs. 1.4% (aOR 1.69; 95% CI 1.14-2.50).

CONCLUSION

Utilization of prostaglandin E₁, compared to E_2, was associated with an increased likelihood of adverse maternal and neonatal outcomes.

Shoulder dystocia and composite adverse outcomes for the maternal-neonatal dyad

BACKGROUND

Although the neonatal morbidity associated with shoulder dystocia are well known, the maternal morbidity caused by this obstetrical emergency is infrequently reported.

OBJECTIVE

This study aimed to assess the composite adverse maternal and neonatal outcomes among vaginal deliveries (at 34 weeks or later) with and without shoulder dystocia.

STUDY DESIGN

This is a secondary analysis of the Consortium of Safe Labor, an observational obstetrical cohort of all vaginal deliveries occurring at 19 hospitals (from 2002-2008) and for which data on the occurrence of shoulder dystocia were available. The composite adverse maternal outcome included third- or fourth-degree perineal laceration, postpartum hemorrhage (>500 cc blood loss for a vaginal delivery and >1000 cc blood loss for cesarean delivery), blood transfusion, chorioamnionitis, endometritis, thromboembolism, admission to intensive care unit, or maternal death. The composite adverse neonatal outcome included an Apgar score of <7 at 5 minutes, a birth injury, neonatal seizure, hypoxic ischemic encephalopathy, or neonatal death. A multivariable Poisson regression was used to estimate the adjusted relative risks with 95% confidence intervals. The area under the receiver operating characteristic curve was constructed to determine if clinical factors would identify shoulder dystocia.

RESULTS

Of the 228,438 women in the overall cohort, 130,008 (59.6%) met the inclusion criteria, and among them, shoulder dystocia was documented in 2159 (1.7%) cases. The rate of composite maternal morbidity was significantly higher among deliveries with shoulder dystocia (14.7%) than without (8.6%; adjusted relative risk, 1.71; 95% confidence interval, 1.64-2.01). The most common maternal morbidity with shoulder dystocia was a third- or fourth-degree laceration (adjusted relative risk, 2.82; 95% confidence interval, 2.39-3.31). The risk of composite neonatal morbidity with shoulder dystocia (12.2%) was also significantly higher than without shoulder dystocia (2.4%) (adjusted relative risk, 5.18; 95% confidence interval, 4.60-5.84). The most common neonatal morbidity was birth injury (adjusted relative risk, 5.39; 95% confidence interval, 4.71-6.17). The area under the curve for maternal characteristics to identify shoulder dystocia was 0.66 and it was 0.67 for intrapartum factors.

CONCLUSION

Although shoulder dystocia is unpredictable, the associated morbidity affects both mothers and newborns. The focus should be on concurrently averting the composite morbidity for the maternal-neonatal dyad with shoulder dystocia.

The association of adverse outcomes with pregnancy conception methods among low-risk term pregnancies

OBJECTIVE

To compare composite neonatal and maternal adverse outcomes among low-risk singleton pregnancies at 37-41 weeks among conception methods: spontaneously-conceived (SC) pregnancy; infertility medications and/or intrauterine insemination (IFM/IUI); and assisted reproductive technology (ART).

DESIGN

Population-based retrospective cohort study.

SETTING

US Vital Statistics datasets 2013-2017.

PATIENT(S)

Low-risk pregnancies (without hypertensive disorders, pregestational or gestational diabetes, or history of preterm birth) of women ≥20 years with nonanomalous singletons, who labored, delivered at 37-41 weeks, and had data on pregnancy conception method.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary outcome was the composite neonatal adverse outcome (CNAO). The secondary outcome was the composite maternal adverse outcome (CMAO).

RESULT(S)

Of the 19.7 million deliveries during the study period, 54.0% (N = 10,676,184) met the inclusion criteria, with 99.0% (N = 10,573,741) being conceived spontaneously, 0.4% (N = 47,227) by IFM/IUI, and 0.5% (N = 55,216) by ART. The overall rate of CNAO was 6.68 per 1,000 live births. Compared with SC, the risk of CNAO was significantly higher among IFM/IUI (adjusted relative risk [aRR], 1.29; 95% CI, 1.18-1.41) and ART (aRR, 1.29; 95% CI, 1.18-1.39). The overall rate of CMAO was 2.50 per 1,000 live births. Compared with SC, the risk of CMAO was significantly increased among IFM/IUI (aRR, 1.72; 95% CI, 1.50-1.97) and ART (aRR, 2.40; 95% CI, 2.17-2.65).

CONCLUSION(S)

Among low-risk term singleton pregnancies, IFM/IUI and ART have modestly higher rates of adverse outcomes to maternal-neonatal dyad than SC.

Neonatal brachial plexus palsy: associated birth injury outcomes, hospital length of stay and costs

OBJECTIVE

To compare the birth injury outcomes and hospital length of stay and costs among newborns delivered at 34-42 weeks with neonatal brachial plexus palsy (NBPP) versus those without.

STUDY DESIGN

We conducted a retrospective, cross-sectional study using data from the National Inpatient Sample to identify all newborns hospitalizations that occurred in the U.S. between 2016 and 2017. We included non-anomalous single liveborn delivered in-hospital at 34-42 weeks. The newborns with NBPP were identified by International Classification of Diseases, 10th Revision, Clinical Modification codes. Birth injury outcomes, and hospital length of stay and hospital costs were examined. A multivariable Poisson regression model with robust error variance was used to examine the association between NBPP and birth injury outcomes. A multivariable generalized linear regression model was used to examine the association between NBPP and hospital length of stay and hospital costs.

RESULTS

Of 7,019,722 non-anomalous single liveborn delivered at 34-42 weeks in the U.S. from 2016 to 2017, the rate of NBPP (n = 6695) was 0.95 per 1000 newborn hospitalizations. After multivariable regression adjustment, compared to newborns without NBPP, the risk of the composite birth injury outcome was 2.91 (95% CI 2.61-3.25) times higher in those with NBPP. Similar results of an increased risk among newborns with NBPP were observed in all individual birth injury outcomes. Compared to newborns without NBPP, after adjustment, the hospital length of stay was 1.48 (95% IC 1.38-1.59) times higher and the hospital costs were 2.21 (95% CI 1.97-2.48) times higher in those with NBPP.

CONCLUSIONS

Among newborns delivered at 34-42 weeks, the risk of associated birth injuries, hospital length of stay and costs, were significantly higher in newborns with NBPP than those without.

Chorioamnionitis and adverse outcomes in low-risk pregnancies: a population-based study

OBJECTIVE

To compare the composite neonatal and maternal adverse outcomes among low-risk pregnancies with versus without chorioamnionitis.

METHODS

We conducted a retrospective cohort study using U.S. Vital Statistics Data. The study population was restricted to full term, low-risk, singleton pregnancies. Pregnancies were categorized into those affected and unaffected by chorioamnionitis. The primary outcome was composite neonatal adverse outcome and the secondary outcome was composite maternal adverse outcome. Multivariable Poisson regression models with robust error variance were used to examine the factors associated with chorioamnionitis and to evaluate the association between chorioamnionitis and adverse outcomes [using adjusted relative risk (aRR) and 95% confidence interval (CI)].

RESULTS

Of 19.7 million live births, 59.4% met inclusion criteria; among them, 1.7% were complicated by chorioamnionitis. The risk of composite neonatal adverse outcome was higher in newborns delivered by women with chorioamnionitis (aRR = 3.40; 95% CI = 3.30-3.49). Compared to women without chorioamnionitis, those with chorioamnionitis had a higher risk of composite maternal adverse outcome (aRR = 2.42; 95% CI = 2.31-2.55). Infant mortality was also higher in affected pregnancies (aRR = 1.23; 95% CI = 1.09-1.38).

CONCLUSION

Among low-risk pregnancies, chorioamnionitis is associated with a higher risk of composite neonatal and maternal adverse outcomes. Infant death is also increased.

Predictors of neonatal brachial plexus palsy subsequent to resolution of shoulder dystocia

OBJECTIVE

The objective was to ascertain factors among deliveries complicated by shoulder dystocia (SD) and neonatal brachial plexus palsy (NBPP).

METHODS

At 11 hospitals, deliveries complicated by SD were identified. The inclusion criteria were vaginal delivery of non-anomalous, singleton at 34-42 weeks. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) were calculated. Receiver operating characteristic (ROC) curves were created to evaluate the predictive value of the models for NBPP.

RESULTS

Of the 62,939 individuals who delivered vaginally, 1,134 (1.8%) had SD and met other inclusion criteria. Among the analytic cohort, 74 (6.5%) had NBPP. The factor known before delivery which was associated with NBPP was diabetes (aOR = 3.87; 95% CI = 2.13-7.01). After delivery, the three factors associated with NBPP were: (1) birthweight of at least 4000 g (aOR = 1.83; 95% CI = 1.05-3.20); (2) calling for help during the SD (aOR = 4.09, 95% CI = 2.29-7.30), and (3) the duration of SD ≥120 sec (aOR = 2.47, 95% CI = 1.30-4.69). The AUC under the ROC curve for these independent factors was 0.79 (95% CI = 0.77 - 0.82).

CONCLUSIONS

Few factors were identified that were associated with NBPP after SD, but they could not reliably predict which neonates will experience the complication.