Tranexamic Acid to Prevent Obstetrical Hemorrhage after Cesarean Delivery.

BACKGROUND: Prophylactic use of tranexamic acid at the time of cesarean delivery has been shown to decrease the calculated blood loss, but the effect on the need for blood transfusions is unclear. METHODS: We randomly assigned patients undergoing cesarean delivery at 31 U.S. hospitals to receive either tranexamic acid or placebo after umbilical-cord clamping. The primary outcome was a composite of maternal death or blood transfusion by hospital discharge or 7 days post partum, whichever came first. Key secondary outcomes were estimated intraoperative blood loss of more than 1 liter (prespecified as a major secondary outcome), interventions for bleeding and related complications, the preoperative-to-postoperative change in the hemoglobin level, and postpartum infectious complications. Adverse events were assessed. RESULTS: A total of 11,000 participants underwent randomization (5529 to the tranexamic acid group and 5471 to the placebo group); scheduled cesarean delivery accounted for 50.1% and 49.2% of the deliveries in the respective groups. A primary-outcome event occurred in 201 of 5525 participants (3.6%) in the tranexamic acid group and in 233 of 5470 (4.3%) in the placebo group (adjusted relative risk, 0.89; 95.26% confidence interval [CI], 0.74 to 1.07; P = 0.19). Estimated intraoperative blood loss of more than 1 liter occurred in 7.3% of the participants in the tranexamic acid group and in 8.0% of those in the placebo group (relative risk, 0.91; 95% CI, 0.79 to 1.05). Interventions for bleeding complications occurred in 16.1% of the participants in the tranexamic acid group and in 18.0% of those in the placebo group (relative risk, 0.90; 95% CI, 0.82 to 0.97); the change in the hemoglobin level was -1.8 g per deciliter and -1.9 g per deciliter, respectively (mean difference, -0.1 g per deciliter; 95% CI, -0.2 to -0.1); and postpartum infectious complications occurred in 3.2% and 2.5% of the participants, respectively (relative risk, 1.28; 95% CI, 1.02 to 1.61). The frequencies of thromboembolic events and other adverse events were similar in the two groups. CONCLUSIONS: Prophylactic use of tranexamic acid during cesarean delivery did not lead to a significantly lower risk of a composite outcome of maternal death or blood transfusion than placebo. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT03364491.).

Treatment for Mild Chronic Hypertension during Pregnancy.

BACKGROUND: The benefits and safety of the treatment of mild chronic hypertension (blood pressure, <160/100 mm Hg) during pregnancy are uncertain. Data are needed on whether a strategy of targeting a blood pressure of less than 140/90 mm Hg reduces the incidence of adverse pregnancy outcomes without compromising fetal growth. METHODS: In this open-label, multicenter, randomized trial, we assigned pregnant women with mild chronic hypertension and singleton fetuses at a gestational age of less than 23 weeks to receive antihypertensive medications recommended for use in pregnancy (active-treatment group) or to receive no such treatment unless severe hypertension (systolic pressure, ≥160 mm Hg; or diastolic pressure, ≥105 mm Hg) developed (control group). The primary outcome was a composite of preeclampsia with severe features, medically indicated preterm birth at less than 35 weeks' gestation, placental abruption, or fetal or neonatal death. The safety outcome was small-for-gestational-age birth weight below the 10th percentile for gestational age. Secondary outcomes included composites of serious neonatal or maternal complications, preeclampsia, and preterm birth. RESULTS: A total of 2408 women were enrolled in the trial. The incidence of a primary-outcome event was lower in the active-treatment group than in the control group (30.2% vs. 37.0%), for an adjusted risk ratio of 0.82 (95% confidence interval [CI], 0.74 to 0.92; P<0.001). The percentage of small-for-gestational-age birth weights below the 10th percentile was 11.2% in the active-treatment group and 10.4% in the control group (adjusted risk ratio, 1.04; 95% CI, 0.82 to 1.31; P = 0.76). The incidence of serious maternal complications was 2.1% and 2.8%, respectively (risk ratio, 0.75; 95% CI, 0.45 to 1.26), and the incidence of severe neonatal complications was 2.0% and 2.6% (risk ratio, 0.77; 95% CI, 0.45 to 1.30). The incidence of any preeclampsia in the two groups was 24.4% and 31.1%, respectively (risk ratio, 0.79; 95% CI, 0.69 to 0.89), and the incidence of preterm birth was 27.5% and 31.4% (risk ratio, 0.87; 95% CI, 0.77 to 0.99). CONCLUSIONS: In pregnant women with mild chronic hypertension, a strategy of targeting a blood pressure of less than 140/90 mm Hg was associated with better pregnancy outcomes than a strategy of reserving treatment only for severe hypertension, with no increase in the risk of small-for-gestational-age birth weight. (Funded by the National Heart, Lung, and Blood Institute; CHAP ClinicalTrials.gov number, NCT02299414.).

Body Mass Index, Adverse Pregnancy Outcomes, and Cardiovascular Disease Risk.

BACKGROUND: Obesity is a well-established risk factor for both adverse pregnancy outcomes (APOs) and cardiovascular disease (CVD). However, it is not known whether APOs are mediators or markers of the obesity-CVD relationship. This study examined the association between body mass index, APOs, and postpartum CVD risk factors. METHODS: The sample included adults from the nuMoM2b (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be) Heart Health Study who were enrolled in their first trimester (6 weeks-13 weeks 6 days gestation) from 8 United States sites. Participants had a follow-up visit at 3.7 years postpartum. APOs, which included hypertensive disorders of pregnancy, preterm birth, small-for-gestational-age birth, and gestational diabetes, were centrally adjudicated. Mediation analyses estimated the association between early pregnancy body mass index and postpartum CVD risk factors (hypertension, hyperlipidemia, and diabetes) and the proportion mediated by each APO adjusted for demographics and baseline health behaviors, psychosocial stressors, and CVD risk factor levels. RESULTS: Among 4216 participants enrolled, mean±SD maternal age was 27±6 years. Early pregnancy prevalence of overweight was 25%, and obesity was 22%. Hypertensive disorders of pregnancy occurred in 15%, preterm birth in 8%, small-for-gestational-age birth in 11%, and gestational diabetes in 4%. Early pregnancy obesity, compared with normal body mass index, was associated with significantly higher incidence of postpartum hypertension (adjusted odds ratio, 1.14 [95% CI, 1.10-1.18]), hyperlipidemia (1.11 [95% CI, 1.08-1.14]), and diabetes (1.03 [95% CI, 1.01-1.04]) even after adjustment for baseline CVD risk factor levels. APOs were associated with higher incidence of postpartum hypertension (1.97 [95% CI, 1.61-2.40]) and hyperlipidemia (1.31 [95% CI, 1.03-1.67]). Hypertensive disorders of pregnancy mediated a small proportion of the association between obesity and incident hypertension (13% [11%-15%]) and did not mediate associations with incident hyperlipidemia or diabetes. There was no significant mediation by preterm birth or small-for-gestational-age birth. CONCLUSIONS: There was heterogeneity across APO subtypes in their association with postpartum CVD risk factors and mediation of the association between early pregnancy obesity and postpartum CVD risk factors. However, only a small or nonsignificant proportion of the association between obesity and CVD risk factors was mediated by any of the APOs, suggesting APOs are a marker of prepregnancy CVD risk and not a predominant cause of postpartum CVD risk.

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.).

Association between stillbirth and severe maternal morbidity.

BACKGROUND: Severe maternal morbidity has been increasing in the past few decades. Few studies have examined the risk of severe maternal morbidity among individuals with stillbirths vs individuals with live-birth deliveries. OBJECTIVE: This study aimed to examine the prevalence and risk of severe maternal morbidity among individuals with stillbirths vs individuals with live-birth deliveries during delivery hospitalization as a primary outcome and during the postpartum period as a secondary outcome. STUDY DESIGN: This was a retrospective cohort study using birth and fetal death certificate data linked to hospital discharge records from California (2008-2018), Michigan (2008-2020), Missouri (2008-2014), Pennsylvania (2008-2014), and South Carolina (2008-2020). Relative risk regression analysis was used to examine the crude and adjusted relative risks of severe maternal morbidity along with 95% confidence intervals among individuals with stillbirths vs individuals with live-birth deliveries, adjusting for birth year, state of residence, maternal sociodemographic characteristics, and the obstetric comorbidity index. RESULTS: Of the 8,694,912 deliveries, 35,012 (0.40%) were stillbirths. Compared with individuals with live-birth deliveries, those with stillbirths were more likely to be non-Hispanic Black (10.8% vs 20.5%); have Medicaid (46.5% vs 52.0%); have pregnancy complications, including preexisting diabetes mellitus (1.1% vs 4.3%), preexisting hypertension (2.3% vs 6.2%), and preeclampsia (4.4% vs 8.4%); have multiple pregnancies (1.6% vs 6.2%); and reside in South Carolina (7.4% vs 11.6%). During delivery hospitalization, the prevalence rates of severe maternal morbidity were 791 cases per 10,000 deliveries for stillbirths and 154 cases per 10,000 deliveries for live-birth deliveries, whereas the prevalence rates for nontransfusion severe maternal morbidity were 502 cases per 10,000 deliveries for stillbirths and 68 cases per 10,000 deliveries for live-birth deliveries. The crude relative risk for severe maternal morbidity was 5.1 (95% confidence interval, 4.9-5.3), whereas the adjusted relative risk was 1.6 (95% confidence interval, 1.5-1.8). For nontransfusion severe maternal morbidity among stillbirths vs live-birth deliveries, the crude relative risk was 7.4 (95% confidence interval, 7.0-7.7), whereas the adjusted relative risk was 2.0 (95% confidence interval, 1.8-2.3). This risk was not only elevated among individuals with stillbirth during the delivery hospitalization but also through 1 year after delivery (severe maternal morbidity adjusted relative risk, 1.3; 95% confidence interval, 1.1-1.4; nontransfusion severe maternal morbidity adjusted relative risk, 1.2; 95% confidence interval, 1.1-1.3). CONCLUSION: Stillbirth was found to be an important contributor to severe maternal morbidity.

Prediction of metabolic syndrome following a first pregnancy.

BACKGROUND: The prevalence of metabolic syndrome is rapidly increasing in the United States. We hypothesized that prediction models using data obtained during pregnancy can accurately predict the future development of metabolic syndrome. OBJECTIVE: This study aimed to develop machine learning models to predict the development of metabolic syndrome using factors ascertained in nulliparous pregnant individuals. STUDY DESIGN: This was a secondary analysis of a prospective cohort study (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be Heart Health Study [nuMoM2b-HHS]). Data were collected from October 2010 to October 2020, and analyzed from July 2023 to October 2023. Participants had in-person visits 2 to 7 years after their first delivery. The primary outcome was metabolic syndrome, defined by the National Cholesterol Education Program Adult Treatment Panel III criteria, which was measured within 2 to 7 years after delivery. A total of 127 variables that were obtained during pregnancy were evaluated. The data set was randomly split into a training set (70%) and a test set (30%). We developed a random forest model and a lasso regression model using variables obtained during pregnancy. We compared the area under the receiver operating characteristic curve for both models. Using the model with the better area under the receiver operating characteristic curve, we developed models that included fewer variables based on SHAP (SHapley Additive exPlanations) values and compared them with the original model. The final model chosen would have fewer variables and noninferior areas under the receiver operating characteristic curve. RESULTS: A total of 4225 individuals met the inclusion criteria; the mean (standard deviation) age was 27.0 (5.6) years. Of these, 754 (17.8%) developed metabolic syndrome. The area under the receiver operating characteristic curve of the random forest model was 0.878 (95% confidence interval, 0.846-0.909), which was higher than the 0.850 of the lasso model (95% confidence interval, 0.811-0.888; P<.001). Therefore, random forest models using fewer variables were developed. The random forest model with the top 3 variables (high-density lipoprotein, insulin, and high-sensitivity C-reactive protein) was chosen as the final model because it had the area under the receiver operating characteristic curve of 0.867 (95% confidence interval, 0.839-0.895), which was not inferior to the original model (P=.08). The area under the receiver operating characteristic curve of the final model in the test set was 0.847 (95% confidence interval, 0.821-0.873). An online application of the final model was developed (https://kawakita.shinyapps.io/metabolic/). CONCLUSION: We developed a model that can accurately predict the development of metabolic syndrome in 2 to 7 years after delivery.

Early vs delayed amniotomy following transcervical Foley balloon in the induction of labor: a randomized clinical trial.

BACKGROUND: The optimal timing of amniotomy during labor induction is a topic of ongoing debate due to the potential risks associated with both amniotomy and prolonged labor. As such, individuals in the field of obstetrics and gynecology must carefully evaluate the associated benefits and drawbacks of this procedure. While amniotomy can expedite the labor process, it may also lead to complications such as umbilical cord prolapse, fetal distress, and infection. Therefore, a careful and thorough examination of the risks and benefits of amniotomy during labor induction is essential in making an informed decision regarding the optimal timing of this procedure. OBJECTIVE: This study aimed to determine if an amniotomy within 2 hours after Foley balloon removal reduced the duration of active labor and time taken to achieve vaginal delivery when compared with an amniotomy ≥4 hours after balloon removal among term pregnant women who underwent labor induction. STUDY DESIGN: This was an open-label, randomized controlled trial that was conducted at a single academic center from October 2020 to March 2023. Term participants who were eligible for preinduction cervical ripening with a Foley balloon were randomized into 2 groups, namely the early amniotomy (rupture of membranes within 2 hours after Foley balloon removal) and delayed amniotomy (rupture of membranes performed more than 4 hours after Foley balloon removal) groups. Randomization was stratified by parity. The primary outcome was time from Foley balloon insertion to active phase of labor. Secondary outcomes, including time to delivery, cesarean delivery rates, and maternal and neonatal complications, were analyzed using intention-to-treat and per-protocol analyses. RESULTS: Of the 150 participants who consented and were enrolled, 149 were included in the analysis. In the intention-to-treat population, an early amniotomy did not significantly shorten the time between Foley balloon insertion and active labor when compared with a delayed amniotomy (885 vs 975 minutes; P=.08). An early amniotomy was associated with a significantly shorter time from Foley balloon placement to active labor in nulliparous individuals (1211; 584-2340 vs 1585; 683-2760; P=.02). When evaluating the secondary outcomes, an early amniotomy was associated with a significantly shorter time to active labor onset (312.5 vs 442.5 minutes; P=.02) and delivery (484 vs 587 minutes; P=.03) from Foley balloon removal with a higher rate of delivery within 36 hours (96% vs 85%; P=.03). Individuals in the early amniotomy group reached active labor 1.5 times faster after Foley balloon insertion than those in the delayed group (hazard ratio, 1.5; 95% confidence interval, 1.1-2.2; P=.02). Those with an early amniotomy also reached vaginal delivery 1.5 times faster after Foley balloon removal than those in the delayed group (hazard ratio, 1.5; 95% confidence interval, 1-2.2; P=.03). A delayed amniotomy was associated with a higher rate of postpartum hemorrhage (0% vs 9.5%; P=.01). No significant differences were observed in the cesarean delivery rates, length of hospital stay, maternal infection, or neonatal outcomes. CONCLUSION: Although an early amniotomy does not shorten the time from Foley balloon insertion to active labor, it shortens time from Foley balloon removal to active labor and delivery without increasing complications. The increased postpartum hemorrhage rate in the delayed amniotomy group suggests increased risks with delayed amniotomy.

Desirability of outcome ranking for obstetrical trials: illustration and application to the ARRIVE trial.

BACKGROUND: In randomized trials, 1 primary outcome is typically chosen to evaluate the consequences of an intervention, whereas other important outcomes are relegated to secondary outcomes. This issue is amplified for many obstetrical trials in which an intervention may have consequences for both the pregnant person and the child. In contrast, desirability of outcome ranking, a paradigm shift for the design and analysis of clinical trials based on patient-centric evaluation, allows multiple outcomes-including from >1 individual-to be considered concurrently. OBJECTIVE: This study aimed to describe desirability of outcome ranking methodology tailored to obstetrical trials and to apply the methodology to maternal-perinatal paired (dyadic) outcomes in which both individuals may be affected by an intervention but may experience discordant outcomes (eg, an obstetrical intervention may improve perinatal but worsen maternal outcomes). STUDY DESIGN: This secondary analysis applies the desirability of outcome ranking methodology to data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network ARRIVE trial. The original analysis found no substantial difference in the primary (perinatal composite) outcome, but a decreased risk of the secondary outcome of cesarean delivery with elective induction at 39 weeks. In the present desirability-of-outcome-ranking analysis, dyadic outcomes ranging from spontaneous vaginal delivery without severe neonatal complication (most desirable) to cesarean delivery with perinatal death (least desirable) were classified into 8 categories ranked by overall desirability by experienced investigators. Distributions of the desirability of outcome ranking were compared by estimating the probability of having a more desirable dyadic outcome with elective induction at 39 weeks of gestation than with expectant management. To account for various perspectives on these outcomes, a complementary analysis, called the partial credit strategy, was used to grade outcomes on a 100-point scale and estimate the difference in overall treatment scores between groups using a t test. RESULTS: All 6096 participants from the trial were included. The probability of a better dyadic outcome for a randomly selected patient who was randomized to elective induction was 53% (95% confidence interval, 51-54), implying that elective induction led to a better overall outcome for the dyad when taking multiple outcomes into account concurrently. Furthermore, the desirability-of-outcome-ranking probability of averting cesarean delivery with elective induction was 52% (95% confidence interval, 51-53), which was not at the expense of an operative vaginal delivery or a poorer outcome for the perinate (ie, survival with a severe neonatal complication or perinatal death). Randomization to elective induction was also advantageous in most of the partial credit score scenarios. CONCLUSION: Desirability-of-outcome-ranking methodology is a useful tool for obstetrical trials because it provides a concurrent view of the effect of an intervention on multiple dyadic outcomes, potentially allowing for better translation of data for decision-making and person-centered care.

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.

Blood pressure control in pregnant patients with chronic hypertension and diabetes: should <130/80 be the target?

BACKGROUND: The Chronic Hypertension and Pregnancy Study demonstrated that a target blood pressure of <140/90 mm Hg during pregnancy is associated with improved perinatal outcomes. Outside of pregnancy, pharmacologic therapy for patients with diabetes and hypertension is adjusted to a target blood pressure of <130/80 mm Hg. During pregnancy, patients with both diabetes and chronic hypertension may also benefit from tighter control with a target blood pressure <130/80 mm Hg. OBJECTIVE: We compared perinatal outcomes in patients with hypertension and diabetes who achieved blood pressure <130/80 vs 130 to 139/80 to 89 mm Hg. STUDY DESIGN: This was a secondary analysis of a multcenter randomized controlled trial. Participants were included in this secondary analysis if they had diabetes diagnosed prior to pregnancy or at <20 weeks of gestation and at least 2 recorded blood pressure measurements prior to delivery. Average systolic and diastolic blood pressure were calculated using ambulatory antenatal blood pressures. The primary composite outcome was preeclampsia with severe features, indicated preterm birth <35 weeks, or placental abruption. Secondary outcomes were components of the primary outcome, cesarean delivery, fetal or neonatal death, neonatal intensive care unit admission, and small for gestational age. Comparisons were made between those with an average systolic blood pressure <130 mm Hg and average diastolic blood pressure <80 mm Hg and those with an average systolic blood pressure 130 to 139 mm Hg or diastolic blood pressure 80 to 89 mm Hg using Student's t test and chi-squared tests. Multivariable log-binomial regression models were used to evaluate risk ratios between blood pressure groups for dichotomous outcomes while accounting for baseline covariates. RESULTS: Of 434 participants included, 150 (34.6%) had an average blood pressure less than 130/80 mm Hg. Participants with an average blood pressure less than 130/80 were more likely to be on antihypertensive medications at the start of pregnancy and more likely to have newly diagnosed diabetes mellitus prior to 20 weeks. Participants with an average blood pressure less than 130/80 mm Hg were less likely to have the primary adverse perinatal outcome (19.3% vs 46.5%, adjusted relative risk 0.43, 95% confidence interval 0.30-0.61, P<.01), with decreased risks specifically of preeclampsia with severe features (adjusted relative risk 0.35, 95% confidence interval 0.23-0.54) and indicated preterm birth prior to 35 weeks (adjusted relative risk 0.44, 95% confidence interval 0.24-0.79). The risk of neonatal intensive care unit admission was lower in the lower blood pressure group (adjusted relative risk 0.74, 95% confidence interval 0.59-0.94). No differences were noted in cesarean delivery (adjusted relative risk 1.04, 95% confidence interval 0.90-1.20), fetal or neonatal death (adjusted relative risk 0.59, 95% confidence interval 0.12-2.92). Small for gestational age less than the 10th percentile was lower in the lower blood pressure group (adjusted relative risk 0.37, 95% confidence interval 0.14-0.96). CONCLUSION: In those with chronic hypertension and diabetes prior to 20 weeks, achieving an average goal blood pressure of <130/80 mm Hg may be associated with improved perinatal outcomes.

Peripheral Use of Vasopressors in Shock: Clinical Considerations and Recommendations for Use in Obstetrics.

OBJECTIVE: This study aimed to evaluate the safety of peripheral administration of vasopressor agents among patients with circulatory shock. STUDY DESIGN: We reviewed the published literature evaluating the use of peripheral norepinephrine in patients with shock and proposed a protocol for use in labor and delivery units. RESULTS: Peripheral administration of norepinephrine is a safe and potentially lifesaving intervention for patients in labor and delivery with extremely low complication rates. CONCLUSION: Adoption of a protocol for peripheral administration of vasopressors in labor and delivery is safe and may prevent life threatening delays in hemodynamic resuscitation. KEY POINTS: · Administering vasopressors through a peripheral line is safe and helps avoid delays in care.. · An established protocol is essential for the safe peripheral administration of vasopressors.. · Understanding continuous blood pressure monitoring is crucial for managing critically ill patients..

Prediction of COVID-19 Severity at Delivery after Asymptomatic or Mild COVID-19 during Pregnancy.

OBJECTIVE: This study aimed to develop a prediction model that estimates the probability that a pregnant person who has had asymptomatic or mild coronavirus disease 2019 (COVID-19) prior to delivery admission will progress in severity to moderate, severe, or critical COVID-19. STUDY DESIGN: This was a secondary analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients who delivered from March through December 2020 at hospitals across the United States. Those eligible for this analysis presented for delivery with a current or previous asymptomatic or mild SARS-CoV-2 infection. The primary outcome was moderate, severe, or critical COVID-19 during the delivery admission through 42 days postpartum. The prediction model was developed and internally validated using stratified cross-validation with stepwise backward elimination, incorporating only variables that were known on the day of hospital admission. RESULTS: Of the 2,818 patients included, 26 (0.9%; 95% confidence interval [CI], 0.6-1.3%) developed moderate-severe-critical COVID-19 during the study period. Variables in the prediction model were gestational age at delivery admission (adjusted odds ratio [aOR], 1.15; 95% CI, 1.08-1.22 per 1-week decrease), a hypertensive disorder in a prior pregnancy (aOR 3.05; 95% CI, 1.25-7.46), and systolic blood pressure at admission (aOR, 1.04; 95% CI, 1.02-1.05 per mm Hg increase). This model yielded an area under the receiver operating characteristic curve of 0.82 (95% CI, 0.72-0.91). CONCLUSION: Among individuals presenting for delivery who had asymptomatic-mild COVID-19, gestational age at delivery admission, a hypertensive disorder in a prior pregnancy, and systolic blood pressure at admission were predictive of delivering with moderate, severe, or critical COVID-19. This prediction model may be a useful tool to optimize resources for SARS-CoV-2-infected pregnant individuals admitted for delivery. KEY POINTS: · Three factors were associated with delivery with more severe COVID-19.. · The developed model yielded an area under the receiver operating characteristic curve of 0.82 and model fit was good.. · The model may be useful tool for SARS-CoV-2 infected pregnancies admitted for delivery..

Gestational Weight Gain and Neonatal Biometry during the COVID-19 Pandemic: A Multicenter Observational Cohort.

OBJECTIVE: This study aimed to test the hypothesis that being pregnant and delivering during the coronavirus disease 2019 (COVID-19) pandemic was associated with changes in gestational weight gain (GWG) or frequency of small- (SGA) or large-for-gestational-age (LGA) neonates. STUDY DESIGN: Secondary analysis of a multicenter observational cohort comparing pregnant people who delivered during the COVID-19 pandemic (June-December 2020) to people who delivered prior to the pandemic (March-December 2019). Those with multiple gestations, fetuses with major congenital anomalies, implausible GWG values, unavailable body mass index (BMI), or who were severe acute respiratory syndrome coronavirus-2-positive were excluded. The primary outcome was frequency of optimal recommended GWG based on prepregnancy BMI. Neonatal outcomes included birth weight, ponderal index, and frequency of SGA, LGA, and small head circumference for live births. Multivariable regression analysis was used to assess associations between exposure to the pandemic and outcomes. RESULTS: A total of 10,717 pregnant people were included in our analysis. A total of 4,225 pregnant people were exposed to the pandemic and 6,492 pregnant people delivered prior to the COVID-19 pandemic. Pregnant people exposed to the pandemic were older and more likely to have gestational diabetes. The frequency of appropriate GWG was 28.0% during the pandemic and 27.6% before the pandemic (adjusted odds ratio [aOR]: 1.02, 95% confidence interval [CI]: 0.93-1.11). Excessive GWG was more likely (54.9 vs. 53.1%; aOR: 1.08, 95% CI: 1.001-1.17), and inadequate GWG was less likely during the pandemic (17.0 vs. 19.3%; aOR: 0.86, 95% CI: 0.77-0.95). The frequency of SGA was 5.4% during the pandemic and 6.1% before the pandemic (aOR: 0.90, 95% CI: 0.76-1.06), and the frequency of LGA was 16.0% during the pandemic versus 15.0% before the pandemic (aOR: 1.06, 95% CI: 0.95-1.18). Other neonatal outcomes including birth weight percentile (62.1 [35.8-83.2] vs. 60.2 [34.4-82.2]; adjusted mean difference (aMD) = 1.50, 95% CI: -0.28 to 3.29), ponderal index (2.6 g/cm3 [2.4-2.8] in both groups; aMD = 0.01, 95% CI: 0.00-0.02), and small head circumference for livebirths (<10th percentile [8.2 vs. 8.1%; aOR: 1.03, 95% CI: 0.89-1.19], <3rd percentile [3.5 vs. 3.1%; aOR: 1.16, 95% CI: 0.93-1.44]) were similar between groups as well. CONCLUSION: Being pregnant and delivering during the COVID-19 pandemic was associated with a higher likelihood of excessive GWG and a lower likelihood of inadequate GWG. KEY POINTS: · Delivering during the COVID-19 pandemic was associated with higher likelihood of excessive GWG.. · Delivering during the COVID-19 pandemic was associated with lower likelihood of inadequate GWG.. · COVID-19 pandemic was not associated with changes in frequency of SGA or LGA..

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..

Association of Mild Iodine Insufficiency during Pregnancy with Child Neurodevelopment in Patients with Subclinical Hypothyroidism or Hypothyroxinemia.

OBJECTIVE: Our objective was to evaluate whether iodine status in pregnant patients with either subclinical hypothyroidism or hypothyroxinemia in the first half of pregnancy is associated with measures of behavior and neurodevelopment in children through the age of 5 years. STUDY DESIGN: This is a secondary analysis of a multicenter study consisting of two randomized, double-masked, placebo-controlled treatment trials conducted in parallel. Patients with a singleton gestation before 20 weeks' gestation underwent thyroid screening using serum thyrotropin and free thyroxine. Participants with subclinical hypothyroidism or hypothyroxinemia were randomized to levothyroxine replacement or an identical placebo. At randomization, maternal urine was collected and stored for subsequent urinary iodine excretion analysis. Urinary iodine concentrations greater than 150 µg/L were considered iodine sufficient, and concentrations of 150 µg/L or less were considered iodine insufficient. The primary outcome was a full-scale intelligence quotient (IQ) score at the age of 5 years, the general conceptual ability score from the Differential Ability Scales-II at the age of 3 if IQ was not available, or death before 3 years. RESULTS: A total of 677 pregnant participants with subclinical hypothyroidism and 526 with hypothyroxinemia were randomized. The primary outcome was available in 1,133 (94%) of children. Overall, 684 (60%) of mothers were found to have urinary iodine concentrations >150 µg/L. Children of iodine-sufficient participants with subclinical hypothyroidism had similar primary outcome scores when compared to children of iodine-insufficient participants (95 [84-105] vs. 96 [87-109], P adj = 0.73). After adjustment, there was also no difference in IQ scores among children of participants with hypothyroxinemia at 5 to 7 years of age (94 [85 - 102] and 91 [81 - 100], Padj 1/4 0.11). Treatment with levothyroxine was not associated with neurodevelopmental or behavioral outcomes regardless of maternal iodine status (p > 0.05). CONCLUSION: Maternal urinary iodine concentrations ≤150 µg/L were not associated with abnormal cognitive or behavioral outcomes in offspring of participants with either subclinical hypothyroidism or hypothyroxinemia. KEY POINTS: · Most pregnant patients with subclinical thyroid disease are iodine sufficient.. · Mild maternal iodine insufficiency is not associated with lower offspring IQ at 5 years.. · Iodine supplementation in subclinical thyroid disease is unlikely to improve IQ..

Neurodevelopmental Outcomes After Late Preterm Antenatal Corticosteroids: The ALPS Follow-Up Study.

Importance: The Antenatal Late Preterm Steroids (ALPS) trial changed clinical practice in the United States by finding that antenatal betamethasone at 34 to 36 weeks decreased short-term neonatal respiratory morbidity. However, the trial also found increased risk of neonatal hypoglycemia after betamethasone. This follow-up study focused on long-term neurodevelopmental outcomes after late preterm steroids. Objective: To evaluate whether administration of late preterm (34-36 completed weeks) corticosteroids affected childhood neurodevelopmental outcomes. Design, Setting, and Participants: Prospective follow-up study of children aged 6 years or older whose birthing parent had enrolled in the multicenter randomized clinical trial, conducted at 13 centers that participated in the Maternal-Fetal Medicine Units (MFMU) Network cycle from 2011-2016. Follow-up was from 2017-2022. Exposure: Twelve milligrams of intramuscular betamethasone administered twice 24 hours apart. Main Outcome and Measures: The primary outcome of this follow-up study was a General Conceptual Ability score less than 85 (-1 SD) on the Differential Ability Scales, 2nd Edition (DAS-II). Secondary outcomes included the Gross Motor Function Classification System level and Social Responsiveness Scale and Child Behavior Checklist scores. Multivariable analyses adjusted for prespecified variables known to be associated with the primary outcome. Sensitivity analyses used inverse probability weighting and also modeled the outcome for those lost to follow-up. Results: Of 2831 children, 1026 enrolled and 949 (479 betamethasone, 470 placebo) completed the DAS-II at a median age of 7 years (IQR, 6.6-7.6 years). Maternal, neonatal, and childhood characteristics were similar between groups except that neonatal hypoglycemia was more common in the betamethasone group. There were no differences in the primary outcome, a general conceptual ability score less than 85, which occurred in 82 (17.1%) of the betamethasone vs 87 (18.5%) of the placebo group (adjusted relative risk, 0.94; 95% CI, 0.73-1.22). No differences in secondary outcomes were observed. Sensitivity analyses using inverse probability weighting or assigning outcomes to children lost to follow-up also found no differences between groups. Conclusion and Relevance: In this follow-up study of a randomized clinical trial, administration of antenatal corticosteroids to persons at risk of late preterm delivery, originally shown to improve short-term neonatal respiratory outcomes but with an increased rate of hypoglycemia, was not associated with adverse childhood neurodevelopmental outcomes at age 6 years or older.

Causal Genetic Variants in Stillbirth.

BACKGROUND: In the majority of cases, the cause of stillbirth remains unknown despite detailed clinical and laboratory evaluation. Approximately 10 to 20% of stillbirths are attributed to chromosomal abnormalities. However, the causal nature of single-nucleotide variants and small insertions and deletions in exomes has been understudied. METHODS: We generated exome sequencing data for 246 stillborn cases and followed established guidelines to identify causal variants in disease-associated genes. These genes included those that have been associated with stillbirth and strong candidate genes. We also evaluated the contribution of 18,653 genes in case-control analyses stratified according to the degree of depletion of functional variation (described here as "intolerance" to variation). RESULTS: We identified molecular diagnoses in 15 of 246 cases of stillbirth (6.1%) involving seven genes that have been implicated in stillbirth and six disease genes that are good candidates for phenotypic expansion. Among the cases we evaluated, we also found an enrichment of loss-of-function variants in genes that are intolerant to such variation in the human population (odds ratio, 2.15; 95% confidence interval [CI], 1.46 to 3.06). Loss-of-function variants in intolerant genes were concentrated in genes that have not been associated with human disease (odds ratio, 2.22; 95% CI, 1.41 to 3.34), findings that differ from those in two postnatal clinical populations that were also evaluated in this study. CONCLUSIONS: Our findings establish the diagnostic utility of clinical exome sequencing to evaluate the role of small genomic changes in stillbirth. The strength of the novel risk signal (as generated through the stratified analysis) was similar to that in known disease genes, which indicates that the genetic cause of stillbirth remains largely unknown. (Funded by the Institute for Genomic Medicine.).

Identifying risk of stillbirth using machine learning.

BACKGROUND: Previous predictive models using logistic regression for stillbirth do not leverage the advanced and nuanced techniques involved in sophisticated machine learning methods, such as modeling nonlinear relationships between outcomes. OBJECTIVE: This study aimed to create and refine machine learning models for predicting stillbirth using data available before viability (22-24 weeks) and throughout pregnancy, as well as demographic, medical, and prenatal visit data, including ultrasound and fetal genetics. STUDY DESIGN: This is a secondary analysis of the Stillbirth Collaborative Research Network, which included data from pregnancies resulting in stillborn and live-born infants delivered at 59 hospitals in 5 diverse regions across the United States from 2006 to 2009. The primary aim was the creation of a model for predicting stillbirth using data available before viability. Secondary aims included refining models with variables available throughout pregnancy and determining variable importance. RESULTS: Among 3000 live births and 982 stillbirths, 101 variables of interest were identified. Of the models incorporating data available before viability, the random forests model had 85.1% accuracy (area under the curve) and high sensitivity (88.6%), specificity (85.3%), positive predictive value (85.3%), and negative predictive value (84.8%). A random forests model using data collected throughout pregnancy resulted in accuracy of 85.0%; this model had 92.2% sensitivity, 77.9% specificity, 84.7% positive predictive value, and 88.3% negative predictive value. Important variables in the previability model included previous stillbirth, minority race, gestational age at the earliest prenatal visit and ultrasound, and second-trimester serum screening. CONCLUSION: Applying advanced machine learning techniques to a comprehensive database of stillbirths and live births with unique and clinically relevant variables resulted in an algorithm that could accurately identify 85% of pregnancies that would result in stillbirth, before they reached viability. Once validated in representative databases reflective of the US birthing population and then prospectively, these models may provide effective risk stratification and clinical decision-making support to better identify and monitor those at risk of stillbirth.

Copy number variants and fetal growth in stillbirths.

BACKGROUND: Fetal growth abnormalities are associated with a higher incidence of stillbirth, with small and large for gestational age infants incurring a 3 to 4- and 2 to 3-fold increased risk, respectively. Although clinical risk factors such as diabetes, hypertension, and placental insufficiency have been associated with fetal growth aberrations and stillbirth, the role of underlying genetic etiologies remains uncertain. OBJECTIVE: This study aimed to assess the relationship between abnormal copy number variants and fetal growth abnormalities in stillbirths using chromosomal microarray. STUDY DESIGN: A secondary analysis utilizing a cohort study design of stillbirths from the Stillbirth Collaborative Research Network was performed. Exposure was defined as abnormal copy number variants including aneuploidies, pathogenic copy number variants, and variants of unknown clinical significance. The outcomes were small for gestational age and large for gestational age stillbirths, defined as a birthweight <10th percentile and greater than the 90th percentile for gestational age, respectively. RESULTS: Among 393 stillbirths with chromosomal microarray and birthweight data, 16% had abnormal copy number variants. The small for gestational age outcome was more common among those with abnormal copy number variants than those with a normal microarray (29.5% vs 16.5%; P=.038). This finding was consistent after adjusting for clinically important variables. In the final model, only abnormal copy number variants and maternal age remained significantly associated with small for gestational age stillbirths, with an adjusted odds ratio of 2.22 (95% confidence interval, 1.12-4.18). Although large for gestational age stillbirths were more likely to have an abnormal microarray: 6.2% vs 3.3% (P=.275), with an odds ratio of 2.35 (95% confidence interval, 0.70-7.90), this finding did not reach statistical significance. CONCLUSION: Genetic abnormalities are more common in the setting of small for gestational age stillborn fetuses. Abnormal copy number variants not detectable by traditional karyotype make up approximately 50% of the genetic abnormalities in this population.

Long-term neurodevelopmental follow-up of children exposed to pravastatin in utero.

BACKGROUND: Preeclampsia, especially before term, increases the risk of child neurodevelopmental adverse outcomes. Biological plausibility, preclinical studies, and pilot clinical trials conducted by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Obstetric-Fetal Pharmacology Research Centers Network support the safety and use of pravastatin to prevent preeclampsia. OBJECTIVE: This study aimed to determine the effect of antenatal pravastatin treatment in high-risk pregnant individuals on their child's health, growth, and neurodevelopment. STUDY DESIGN: This was an ancillary follow-up cohort study of children born to mothers who participated in the Obstetric-Fetal Pharmacology Research Centers Network pilot trials of pravastatin vs placebo in individuals at high risk of preeclampsia (ClinicalTrials.gov; identifier NCT01717586). After obtaining written informed consent (and assent as appropriate), the parent was instructed to complete the Child Behavior Checklist. To assess the child's motor, cognitive, and developmental outcomes, a certified and blinded study psychologist completed child motor, cognitive, emotional, and behavioral assessments using validated tools. Given the small number of individuals in the studies, the 10- and 20-mg pravastatin groups were combined into 1 group, and the results of the pravastatin group were compared with that of the placebo group. RESULTS: Of 40 children born to mothers in the original trial, 30 (15 exposed in utero to pravastatin and 15 to placebo) were enrolled in this follow-up study. The time of follow-up, which was 4.7 years (interquartile range, 2.5-6.9), was not different between children in the pravastatin group and children in the placebo group. There was no difference in the child's body mass index percentiles per sex and corrected age, the rates of extremes of body mass index percentiles, or the report of any other medical or developmental complications between the 2 groups. No child born in the pravastatin group had any limitation in motor assessment compared with 2 children (13.3%) who walked with difficulty and 4 children (26.7%) who had reduced manual abilities in the placebo group. Moreover, children born to mothers who received pravastatin had a higher general mean conceptual ability score (98.2±16.7 vs 89.7±11.0; P=.13) and a lower frequency (15.4% vs 35.7%; P=.38) of having a score of <85 (ie, 1 standard deviation lower than the mean) compared with those in the placebo group. Finally, there was no difference in the parents' report on the Child Behavior Checklist between the 2 groups. CONCLUSION: This study reported on the long-term neuromotor, cognitive, and behavioral outcomes among children exposed to pravastatin in utero during the second and third trimesters of pregnancy. Although the data were limited by the original trial's sample size, no identifiable long-term neurodevelopmental safety signal was evident with the use of pravastatin during pregnancy. This favorable neonatal risk-benefit analysis justifies continued research using pravastatin in clinical trials.