American College of Obstetricians and Gynecologists' Committee on Practice Bulletins—Obstetrics. Prediction and Prevention of Spontaneous Preterm Birth: ACOG Practice Bulletin, Number 234

NuMoM2b Study Insights: Primary Exposures, Outcomes, and Directions for Future Research

OBJECTIVE

 To summarize the publications to date from a large obstetric cohort of nulliparous individuals.

STUDY DESIGN

 We summarized all of the publications from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be (nuMoM2b). We descriptively summarized the most common outcomes and exposures reported in current publications.

RESULTS

 Fifty-six publications to date are discussed. The most common primary exposures reported are participant baseline characteristics such as body mass index (24%), sociodemographic characteristics (22%), and sleep factors (16%). These exposures were most commonly measured in the first trimester (77%). The most commonly reported primary outcomes were related to adverse pregnancy outcomes (APOs, 51.6%), with 25% using a composite of multiple APOs as the primary outcome. At least 8,000 participants were used in the analyses of over half of the publications.

CONCLUSION

 The nuMoM2b study has generated a diverse array of publications and conclusions on factors associated with APOs. The publicly available data set from the nuMoM2b study continues to hold potential for considerable advances, new insights, and future research opportunities to optimize pregnancy and pregnancy-related health.

KEY POINTS

· The nuMoM2b pregnancy cohort has generated 56 publications thus far.. · The main findings of these publications are summarized and categorized in this work.. · The data and specimens from this cohort are available and can answer many clinical questions..

Reevaluating Associations between Prenatal Care Utilization and Current Trends in Preterm Birth

OBJECTIVE

 Studies have suggested an association between prenatal care (PNC) and preterm birth (PTB). We evaluated trends in PTB and association of PNC and PTB.

STUDY DESIGN

 This was a retrospective cohort study of singleton, viable nonanomalous deliveries from 1991 to 2018. PNC utilization was defined by World Health Organization using number of visits: adequate (≥8), suboptimal (5-7), and inadequate (<5). Primary outcome was PTB. Tests of trend were used to assess changes in PTB over time. Baseline characteristics and outcomes were compared. Logistic regression estimated the association of PNC and PTB. We evaluated for effect modification by year of birth.

RESULTS

 Of 92,294 patients, 14,057 (15%) had PTB. Inadequate and suboptimal PNC were associated with higher odds of PTB compared to adequate PNC (adjusted odds ratios = [aOR 6.21], 95% confidence interval [CI]: 5.84-6.60; aOR = 3.57, 95% CI: 3.36-3.79). Inadequate PNC was associated with higher odds of PTB over time (effect modification p < 0.0001). Inadequate PNC was associated with 5.4 times higher odds of PTB in 1998, 7.0 times in 2008, and 9.1 times in 2018.

CONCLUSION

 Despite an increase in adequate PNC, there was a rise in PTB associated with inadequate and suboptimal PNC. PNC utilization was a stronger risk factor in recent years with higher PTB in patients who attended more than five PNC visits.

KEY POINTS

· PNC utilization is associated with the risk of PTB.. · Despite an increase in PNC utilization, PTB rates have increased.. · There is an even stronger association between PNC utilization and PTB over time..

Hepatitis C Virus Infection in Pregnant Individuals with Opioid Use Disorder and Its Association with Preterm Birth

OBJECTIVE

 Both hepatitis C virus (HCV) and opioid use disorder (OUD) have been associated with higher rates of preterm birth (PTB). It is unknown whether the higher prevalence of HCV in individuals with OUD may contribute to this association. The objective of this study is to evaluate the association between HCV and PTB in pregnant individuals with OUD.

STUDY DESIGN

 We conducted a retrospective cohort of pregnant individuals with OUD who participated in more than three visits in a co-located multidisciplinary program. Inclusion criteria were a diagnosis of OUD, participation in treatment/prenatal care program, and laboratory evaluation of HCV status. The primary exposure was the presence of HCV antibodies, and secondarily, a detectable viral load (viremia). The primary outcome was PTB, which was further classified as spontaneous or iatrogenic. Multivariable logistic regression was used to detect associations while adjusting for race, history of prior PTB, and tobacco use.

RESULTS

 A total of 941 individuals were included in the study, 404 with HCV and 537 without. Rates of PTB did not differ between those with compared to those without HCV (20.3 vs. 23.8%, adjusted odds ratio [aOR] = 0.75 [95% confidence interval (CI): 0.53-1.07]). There were similar rates of spontaneous PTB (13.1 vs. 16.2%, aOR = 0.79 [95% CI: 0.43-1.45]) and iatrogenic PTB (7.2 vs. 7.6%, aOR = 1.26 [95% CI: 0.69-2.30]). Comparing those with viremia to those without, there were also similar rates of overall PTB (21.6 vs. 17.9%, aOR = 0.86 [95% CI: 0.52-1.44]), spontaneous PTB (13.3 vs. 12.9%, aOR = 0.97 [95% CI: 0.52-1.87]), and iatrogenic PTB (8.3 vs. 5.0%, aOR = 1.83 [95% CI: 0.76-4.94]).

CONCLUSION

 HCV does not appear to be associated with spontaneous or iatrogenic PTB in pregnant persons with OUD who are engaged in treatment and prenatal care. The role of co-located multidisciplinary prenatal and addiction programs in the association between HCV and PTB warrants further investigation.

KEY POINTS

· Hepatitis C antibodies are not associated with PTB in those with OUD.. · Hepatitis C viremia is not associated with PTB.. · Multidisciplinary treatment programs may contribute to these findings..

Establishment and validation of a predictive model for spontaneous preterm birth in singleton pregnant women

INTRODUCTION

In the current study, we screened for highly sensitive and specific predictors of premature birth, with the aim to establish an sPTB prediction model that is suitable for women in China and easy to operate and popularize, as well as to establish a sPTB prediction scoring system for early, intuitive, and effective assessment of premature birth risk.

METHODS

A total of 685 pregnant women with a single pregnancy during the second trimester (16-26 weeks) were divided into premature and non-premature delivery groups based on their delivery outcomes. Clinical and ultrasound information were collected for both groups, and risk factors that could lead to sPTB in pregnant women were screened and analyzed using a cut-off value. A nomogram was developed to establish a prediction model and scoring system for sPTB. In addition, 119 pregnant women who met the inclusion criteria for the modeling cohort were included in the external validation of the model. The accuracy and consistency of the model were evaluated using the area under the receiver operating characteristic (ROC) and C-calibration curves.

RESULTS

Multivariate logistic regression analysis showed a significant correlation (P < 0.05) between the number of miscarriages in pregnant women, history of miscarriages in the first week of pregnancy, history of preterm birth, CL of pregnant women, open and continuous cervical opening, and the occurrence of sPTB in pregnant women. We drew a nomogram column chart based on the six risk factors mentioned above, obtained a predictive model for sPTB, and established a scoring system to divide premature birth into three risk groups: low, medium, and high. After validating the model, the Hosmer Lemeshow test indicated a good fit (p = 0.997). The modeling queue C calibration curve was close to diagonal (C index = 0.856), confirming that the queue C calibration curve was also close to diagonal (C index = 0.854). The AUCs of the modeling and validation queues were 0.850 and 0.881, respectively.

CONCLUSION

Our predictive model is consistent with China's national conditions, as well as being intuitive and easy to operate, with wide applicability, thus representing a helpful tool to assist with early detection of sPTB in clinical practice, as well as for clinical management in assessing low, medium, and high risks of sPTB.

Uterocervical angle and cervical length measurements for spontaneous preterm birth prediction in low-risk singleton pregnant women: a prospective cohort study

PURPOSE

Preterm birth is the leading cause of early neonatal morbidity and mortality. Strategies to predict preterm birth risk can help improve pregnancy outcomes. Even pregnant women without known risk factors for preterm birth can also experience it. This study aimed to evaluate the ability of the uterocervical angle and cervical length to predict spontaneous preterm birth in low-risk singleton pregnant women.

METHODS

A prospective study on 1107 singleton pregnant women between 16+0 and 23+6 weeks gestation at low risk for spontaneous preterm birth who were treated at the Haiphong Hospital of Obstetrics and Gynecology, Vietnam, between September 2020 and September 2021 was conducted. A single sonographer assessed the cervical length and the uterocervical angle using transvaginal ultrasonography. The patients were followed up until delivery to determine the main pregnancy outcome (spontaneous preterm birth before 37 weeks gestation). The cut-off points for the uterocervical angle and cervical length were established by analyzing the receiver operating characteristic curve. The sensitivity, specificity, likelihood ratio, positive and negative predictive values, and accuracy of the uterocervical angle and cervical length for predicting spontaneous preterm birth were determined.

RESULTS

A uterocervical angle ≥ 99° predicted spontaneous preterm birth at < 37 weeks, with a sensitivity and specificity of 91% and 76%, respectively. A cervical length ≤ 33.8 mm predicted preterm birth at < 37 weeks with a sensitivity and specificity of 25% and 66%, respectively. A uterocervical angle ≥ 99° combined with a cervical length ≤ 33.8 mm yielded the sensitivity, specificity, positive predictive value, likelihood ratio, and accuracy of spontaneous preterm birth prediction of 66%, 93%, 36%, 9, and 91%, respectively; thus provided a significant increase of specificity with an acceptable reduction of sensitivity as compared to cervical length alone.

CONCLUSION

Besides the cervical length, the uterocervical angle can be considered a valuable ultrasound parameter for predicting spontaneous preterm birth in low-risk singleton pregnant women. Combining the uterocervical angle and cervical length yielded stronger spontaneous preterm birth prediction values.

Cerclage Plus Adjuvant Vaginal Progesterone for Preterm Birth Prevention in Patients with a Short or Dilated Cervix without Prior Preterm Birth

OBJECTIVE

 The primary objective was to determine if vaginal progesterone following cerclage for cervical length <10 mm or cervical dilation in patients without a history of spontaneous preterm birth (sPTB) decreased the risk of preterm birth at <34 weeks' gestation compared with cerclage alone. Secondary objectives were to determine if vaginal progesterone following cerclage (1) decreased the risk of preterm birth at <24, <28, and <37 weeks' gestation and (2) increased the latency period from cerclage placement to delivery compared with treatment with cerclage alone.

STUDY DESIGN

 Multicenter retrospective cohort study from 2015 to 2020 of singleton pregnancies, without prior sPTB, who had cerclage placement <24 weeks' gestation for cervical length <10 mm or cervical dilation. Exposure defined as cerclage plus vaginal progesterone postoperatively (dual therapy) and unexposed as cerclage alone (monotherapy), based on surgeon preference.

RESULTS

 We included 122 patients, 78 (64%) treated with dual therapy and 44 (36%) treated with monotherapy. In the crude analysis, dual therapy was associated with a lower risk of delivery at <28 weeks' gestation (13%) compared with monotherapy (34%; crude risk ratio: 0.38 [95% confidence interval (CI): 0.19-0.75]). When adjusted for preoperative vaginal progesterone, results were attenuated (adjusted risk ratio: 0.45 [95% CI: 0.20-1.01]). In both the crude and adjusted analyses, the risk of sPTB was not statistically different at <24, <34 or <37 weeks' gestation. Dual therapy was associated with a greater pregnancy latency from cerclage to delivery (16.3 vs. 14.4 weeks; p = 0.04), and greater gestational age at delivery (37.3 vs. 35.8 weeks' gestation; p = 0.02) compared with monotherapy.

CONCLUSION

 While not statistically significant, the risk of sPTB was lower at all gestational ages studied in patients treated with dual therapy compared with monotherapy. Dual therapy was associated with longer pregnancy latency and greater gestational age at delivery compared with monotherapy.

KEY POINTS

· Dual therapy did not decrease preterm birth risk compared with monotherapy.. · Dual therapy prolonged pregnancy compared with monotherapy.. · Dual therapy can be considered but further studies are needed..

Prediction and prevention of preterm birth: Quality assessment and systematic review of clinical practice guidelines using the AGREE II framework

BACKGROUND

Prediction of pregnancies at risk of preterm birth (PTB) may allow targeted prevention strategies.

OBJECTIVES

To assess quality of clinical practice guidelines (CPGs) and identify areas of agreement and contention in prediction and prevention of spontaneous PTB.

SEARCH STRATEGY

We searched for CPGs regarding PTB prediction and prevention in asymptomatic singleton pregnancies without language restriction in January 2024.

SELECTION CRITERIA

CPGs included were published between July 2017 and December 2023 and contained statements intended to direct clinical practice.

DATA COLLECTION AND ANALYSIS

CPG quality was assessed using the AGREE-II tool. Recommendations were extracted and grouped under domains of prediction and prevention, in general populations and high-risk groups.

MAIN RESULTS

We included 37 CPGs from 20 organizations; all were of moderate or high quality overall. There was consensus in prediction of PTB by identification of risk factors and cervical length screening in high-risk pregnancies and prevention of PTB by universal screening and treatment for asymptomatic bacteriuria, screening and treatment for BV in high-risk pregnancies, and use of preventative progesterone and cerclage. Areas of contention or limited consensus were the role of PTB clinics, universal cervical length measurement, biomarkers and cervical pessaries.

CONCLUSIONS

This review identified strengths and limitations of current PTB CPGs, and areas for future research.

Azithromycin dosing and preterm premature rupture of membranes treatment (ADAPT): a randomized controlled Phase I trial

BACKGROUND

Seven days of antibiotics are recommended in the setting of preterm premature rupture of membranes to promote latency. Azithromycin has generally replaced a 7-day course of erythromycin in current clinical practice. Azithromycin clears from plasma quickly and concentrates in local tissue, which is why daily dosing is not always needed, and local tissue, rather than plasma, concentrations are used to determine dosing. On the basis of limited pharmacokinetic studies in pregnancy, a 1-time dose of 1 g azithromycin may not maintain local (amniotic fluid) drug concentrations above minimum inhibitory concentrations for common genitourinary pathogens (50-500 ng/mL).

OBJECTIVE

We aimed to compare the pharmacokinetics of 1-time vs daily dosing of azithromycin in the setting of preterm prelabor rupture of membranes.

STUDY DESIGN

This is a randomized clinical trial of singletons with preterm prelabor rupture of membranes randomized to 1 g oral azithromycin once or 500 mg oral azithromycin daily for 7 days. The primary outcome was amniotic fluid azithromycin concentrations over 8 days. Secondary outcomes included plasma azithromycin trough concentrations. Plasma was collected at 1-4 hours and 12-24 hours after the first dose and then every 24 hours through 8 days. Amniotic fluid was collected opportunistically throughout the day noninvasively with Always Flex foam pads. We aimed to enroll 20 participants to achieve n=5 still pregnant through 8 days in each group. Continuous variables were compared using the Mann-Whitney U test, and the relationship between azithromycin concentration and time was assessed using linear regression.

RESULTS

The study was halted after 6 enrolled because of lagging enrollment, with 3 in each group. The mean gestational age of enrollment was 27.1±1.7 weeks in the 1 g group and 31.0±1.4 weeks in the 500 mg daily group. One participant in each group had latency to delivery >7 days. Regarding amniotic fluid azithromycin concentration, there was a difference in change in amniotic fluid azithromycin concentration over time between groups (P<.001). The amniotic fluid concentration of azithromycin was relatively stable in the 1 g once group (B,-0.07; 95% confidence interval, -0.44 to 0.31; P=.71), whereas amniotic fluid concentration (ng/mL) increased over time (hours) in the 500 mg daily group (B, 1.3; 95% confidence interval, 0.7-1.9; P<.001). By ≥96 hours, median amniotic fluid levels of azithromycin were lower in the 1 g once group (median, 11; interquartile, 7-56) compared with 500 mg daily (median, 46; interquartile, 23-196), with a median difference of -27 (interquartile,-154 to -1; P=.03). In plasma, there was higher azithromycin concentration during the first 24 hours with 1 g once vs 500 mg daily (median difference, 637 ng/mL; 101-1547; P=.01); however, by ≥96 hours plasma azithromycin declined and was virtually undetectable in the 1 g once group, whereas trough plasma levels in the 500 mg remained elevated (median difference -207 ng/mL; interquartile, -271 to -155; P=.03).

CONCLUSION

Approximately 500 mg daily dosing of azithromycin maintains higher amniotic fluid concentrations and more consistently greater than common minimum inhibitory concentrations over 8 days compared with 1 g once in the setting of PPROM. El resumen está disponible en Español al final del artículo.

Assessing adverse pregnancy outcomes in women with uncontrolled asthma vs. mild asthma: a retrospective comparative analysis

PURPOSE

The aim of this study was to evaluate perinatal outcomes between the uncontrolled asthma group and the mild asthma group and to reveal the relationship between disease severity and adverse maternal-fetal outcomes in this study.

METHODS

This retrospective cohort study analyzed 180 pregnant women diagnosed with asthma, hospitalized, and delivered at our center between September 1, 2019, and December 1, 2021. We compared two groups: 160 with mild asthma and 20 with uncontrolled asthma. Data encompassed maternal characteristics, obstetrical complications, medication use, emergency department admissions for exacerbations, smoking status, and neonatal outcomes.

RESULTS

In the uncontrolled asthma group, hospitalization rates, use of inhaled short-acting β-agonist (SABA), and systemic corticosteroids were significantly higher compared to the mild asthma group (p < 0.01). Maternal and fetal complications were more prevalent in the uncontrolled group, including asthma exacerbations (45% vs. 1.2%), anemia (10% vs. 4.4%), prematurity (25% vs. 9.6%), and intrauterine fetal demise (IUFD) (10% vs. 0.6%). Neonatal outcomes in the uncontrolled group showed higher rates of admission to the neonatal intensive care unit (NICU) (50% vs. 25%), respiratory distress syndrome (RDS) (30% vs. 14%), and intraventricular hemorrhage (IVH) (5% vs. 0%) compared to the mild asthma group.

CONCLUSION

Uncontrolled asthma during pregnancy is associated with higher adverse maternal-fetal and neonatal outcomes compared to mild asthma.

Asymptomatic short cervix and threatened preterm labor: A comparative study on perinatal outcomes

OBJECTIVE

To determine the rate of delivery within 15 days of admission among patients with an asymptomatic short cervix (ASC) compared to those admitted for threatened preterm labor (TPL).

MATERIAL AND METHODS

This retrospective study conducted in a tertiary maternity hospital, included patients with a singleton pregnancy admitted with a cervical length of less than 25 mm between 24 and 34 weeks. The population was divided into two groups, patients with ASC (i.e., with no contractions at admission) and patients with TPL. The primary outcome was the delivery rate within 15 days of admission. Secondary outcomes included gestational age at delivery, preterm delivery rate before 37°/7 weeks and before 34°/7 weeks, admission to delivery interval, 5 min Apgar score and transfer to neonatal intensive care unit rate. The characteristics of the two groups and the primary and secondary outcomes were compared between the two groups using univariate analysis. Two subgroup analysis were performed, one restricted to patients with a mildly modified CL (15 ≤ CL < 25 mm), and one excluding patients at high risk of preterm birth.

RESULTS

Among the 247 included patients, 136 (55.1 %) had TPL, and 111 (44.9 %) ASC. There were no significant differences in the rate of patient who delivered within 15 days of admission between the groups, 13.2 % in the TPL group vs 8.0 % in the ASC group (p = 0.22). Patients in the TPL group had a significantly higher frequency of delivery before 34 weeks compared to those in the ASC group (19.9 % versus 9.0 %, p = 0.02 This finding persisted in the subgroup analysis excluding patients at high risk of preterm birth (16.5 % in the TPL subgroup vs. 6.9 % in the ASC subgroup, p = 0.04). There were no significant differences in the rates of preterm delivery before 37 weeks, the admission-to-delivery interval, or neonatal outcomes between the two groups or within the subgroup analyses.

CONCLUSION

The frequency of delivery within 15 days of admission was not statistically different between patients with an asymptomatic short cervix and those with TPL. Nevertheless, these asymptomatic patients delivered significantly later and less frequently before 34 weeks, with only one in ten requiring corticosteroids.

Development and validation of a risk prediction model for preterm birth in women with gestational diabetes mellitus

OBJECTIVES

This study aims to develop and validate a prediction model for preterm birth in women with gestational diabetes mellitus (GDM).

DESIGN

We conducted a retrospective study on women with GDM who gave birth at the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China, between November 2017 and July 2021. We divided 1879 patients into a development set (n = 1346) and a validation set (n = 533). The development set was used to construct the prediction model for preterm birth using the stepwise logistic regression model. A nomogram and a web calculator were established based on the model. Discrimination and calibration were assessed in both sets.

PATIENTS AND MEASUREMENTS

Patients were women with GDM. Data were collected from medical records. GDM was diagnosed with 75-g oral glucose tolerance test during 24-28 gestational weeks. Preterm birth was definied as gestational age at birth <37 weeks.

RESULTS

The incidence of preterm birth was 9.4%. The predictive model included age, assisted reproductive technology, hypertensive disorders of pregnancy, reproductive system inflammation, intrahepatic cholestasis of pregnancy, high-density lipoprotein, homocysteine, and fasting blood glucose of 75-g oral glucose tolerance test. The area under the receiver operating characteristic curve for the development and validation sets was 0.722 and 0.632, respectively. The model has been adequately calibrated using a calibration curve and the Hosmer-Lemeshow test, demonstrating a correlation between the predicted and observed risk.

CONCLUSION

This study presents a novel, validated risk model for preterm birth in pregnant women with GDM, providing an individualized risk estimation using clinical risk factors in the third trimester of pregnancy.

Predictive value of short cervix in early third trimester for preterm birth in women with normal mid-trimester cervical length

BACKGROUND

Short cervical length in the mid-trimester is a powerful predictor of preterm birth (PTB). However, clinical significance of cervical length in the third trimester for predicting PTB has not been established yet.

OBJECTIVE

To examine the predictive role of a shortened cervix in the third trimester for PTB in women who had a normal cervical length in the second trimester STUDY DESIGN: This retrospective cohort study included women who underwent cervical length measured at least once in both the second trimester (16+0 weeks to 27+6weeks) and the early third trimester (28+0 weeks to 33+6 weeks). Women with short cervical length in the second trimester, those with multiple pregnancies, those who underwent cerclage operation, and those who had iatrogenic PTB were excluded. The study population was divided into two groups based on cervical length in the third trimester: a short cervix (≤25 mm) group and a control group (>25 mm). Rates of PTB (<37 weeks) were compared between two groups. Predictive performances of cervical length in the third trimester for PTB were assessed.

RESULTS

Women with a short cervical length at 28+0 to 33+6 weeks accounted for 12.6% (n=717) of the total study population (n=5682). PTB rate was 9.5% in the short cervix group, which was significantly higher than that (3.2%) in the control group (P<.001). The adjusted odds ratio for short cervical length on PTB was 2.73 (95% CI: 1.96-3.79). A short cervix in the third trimester had a sensitivity of 30.1%, a specificity of 88.1%, a positive predictive value of 9.5%, and a negative predictive value (NPV) of 96.8% in predicting PTB. The addition of third-trimester cervical length to the predictive model significantly increased the area under the curve from 0.64 (95% CI: 0.60-0.68) to 0.67 (95% CI: 0.63-0.71) (P=.002), demonstrating improved predictive performance.

CONCLUSION

Approximately 13% of women with normal cervical length in the mid-trimester had a short cervical length after 28 weeks, which increased the risk of PTB. The high specificity and NPV of third-trimester cervical length measurements underscore their critical utility in identifying women at low risk for preterm delivery.

Activity restriction and risk of adverse pregnancy outcomes

BACKGROUND

Activity restriction is a common recommendation given to patients during pregnancy for various indications, despite lack of definitive data showing improvements in pregnancy outcomes.

OBJECTIVE

To determine if activity restriction (AR) in pregnancy is associated with decreased odds of adverse pregnancy outcomes (APOs).

STUDY DESIGN

Secondary analysis of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b) prospective cohort. Nulliparous singletons were followed at 8 sites from October 2010-September 2013. Demographic and clinical data were collected at 4 timepoints, and participants were surveyed about AR recommendations at 22w0d-29w6d and delivery. We excluded participants missing data on AR and age. Participants were grouped according to history of AR, and APOs included: gestational hypertension (gHTN), preeclampsia/eclampsia, preterm birth (PTB), and small for gestational age (SGA) neonate. Associations between AR and APOs were examined using uni- and multivariable logistic regression models adjusting for a priori identified APO risk factors.

RESULTS

Of 10,038 nuMoM2b participants, 9,312 met inclusion criteria and 1,386 (14.9%) were recommended AR; participants identifying as Black (aOR 0.81 [95% CI 0.68-0.98]) or Hispanic (aOR 0.73 [95% CI 0.61-0.87]) were less likely to be placed on AR when compared to those identifying as White. Overall, 3,197 (34.3%) experienced at least one APO (717 [51.7%] of participants with AR compared to 2,480 [31.3%] participants without AR). After adjustment for baseline differences, the AR group had increased odds of gHTN (aOR 1.61 [95% CI 1.35-1.92]), preeclampsia/eclampsia (aOR 2.52 [95% CI 2.06-3.09]) and iatrogenic and spontaneous PTB (aOR 2.98 [95% CI 2.41-3.69]), but not delivery of an SGA neonate.

CONCLUSION

AR in pregnancy was independently associated with increased odds of hypertensive disorders of pregnancy and PTB, but future prospective work is needed to determine potential causality. Further, participants identifying as Black or Hispanic were significantly less likely to be recommended AR compared to those identifying as White. While AR is not an evidence-based practice, these findings suggest bias may impact which patients receive advice to limit activity in pregnancy.

Serum calcium level at 32 weeks of gestation could be applied as a predictor of preterm delivery: a retrospective study

Preterm delivery (PTD) is associated with severe adverse maternal and neonatal outcomes and higher medical costs. Therefore, PTD warrants more attention. However, predicting PTD remains a challenge for researchers. This study aimed to investigate potential prenatal predictors of PTD. We retrospectively recruited pregnant women who experienced either PTD or term delivery (TD) and underwent laboratory examinations at 32 weeks of gestation. We compared the test results between the two groups and performed logistic regression analysis and receiver operating characteristic (ROC) curve analysis to identify risk factors and predictive factors for PTD. Our investigation revealed that the PTD cohort exhibited statistically significant elevations in lymphocyte count, mean corpuscular hemoglobin concentration, calcium, uric acid, alkaline phosphatase, triglycerides, and total bile acids. Conversely, the PTD group demonstrated statistically significant reductions in mean corpuscular volume, homocysteine, neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), neutrophils to (white blood cells-neutrophils) ratio (dNLR), and (neutrophils × monocytes) to lymphocyte ratio (SIRI). The ROC curve analysis revealed that calcium had an area under the curve (AUC) of 0.705, with a cut-off value of 2.215. Logistic regression analysis showed that premature rupture of membranes was an independent risk factor for PTD. Our study demonstrated that serum calcium levels, NLR, dNLR, and other laboratory tests conducted at 32 weeks of gestation can serve as predictors for PTD. Furthermore, we identified premature rupture of membranes as a risk factor for PTD.

Individual-Level and Community-Level Predictors of Healthy Pregnancy Outcomes in Multigravid Black Women

OBJECTIVE

To identify individual- and community-level factors that predict the odds of multigravid Black women having consecutive pregnancies without adverse pregnancy outcomes.

METHODS

We conducted a secondary analysis of 515 multigravid Black women from a longitudinal observational study (2017-2019). We assessed the presence of adverse pregnancy outcomes (hypertensive disorders, gestational diabetes, preterm birth, fetal growth restriction, placental abruption, and pregnancy loss) for the index and prior pregnancies. We examined U.S. Census data, medical records, and surveys across multiple socioecologic domains: personal, behavioral, socioeconomic, and policy. We estimated adjusted odds ratios (aORs) and 95% CIs for the association between individual- and community-level factors and consecutive healthy pregnancies using hierarchical logistic regression models adjusted for maternal age, body mass index (BMI), gravidity, interpregnancy interval, and median household income.

RESULTS

Among 515 multigravid Black women (age 27±5 years, BMI 31.4±8.9, gravidity 4±2), 38.4% had consecutive healthy pregnancies without adverse pregnancy outcomes. Individual-level factors associated with consecutive healthy pregnancies included normal glucose tolerance (aOR 3.9, 95% CI, 1.2-12.1); employment (aOR 1.9, 95% CI, 1.2-2.9); living in communities with favorable health indicators for diabetes, hypertension, and physical activity; and household income of $50,000 per year or more (aOR 3.5, 95% CI, 1.4-8.7). When individual and community factors were modeled together, only income and employment at the individual and community levels remained significant.

CONCLUSION

Individual and community income and employment are associated with consecutive healthy pregnancies in a cohort of Black patients, emphasizing the need for comprehensive, multilevel systems interventions to reduce adverse pregnancy outcomes for Black women.

Antenatal steroids and neonatal outcomes in late preterm births with pregestational diabetes

OBJECTIVE

To evaluate if antenatal steroid use was associated with a lower rate of respiratory complications in neonates born late preterm to patients with pregestational diabetes mellitus (PGDM).

METHODS

This was a retrospective cohort study of live, singleton, non-anomalous, late preterm births complicated by PGDM using data from the Centers for Disease Control and National Vital Statistics System from 2017 to 2021. The primary (assisted ventilation use >6 h) and secondary neonatal outcomes (immediate assisted ventilation, Apgar score, neonatal intensive care unit [NICU] admission, and surfactant use) were compared between births that received steroids and those that did not. Multivariable analyses were performed to adjust for differences in demographic and clinical characteristics.

RESULTS

There were 24 323 late preterm births with PGDM, of which 4613 received antenatal steroids and 19 710 did not receive steroids. After adjusting for the differences among the two groups, the need for assisted neonatal ventilation for more than 6 h (adjusted odds ratio [aOR] 1.69, 95% confidence interval [CI] 1.53-1.86), immediate assisted neonatal ventilation (aOR 1.67, 95% CI 1.55-1.80), NICU admission (aOR 1.95, 95% CI 1.81-2.10), and surfactant use (aOR 1.68, 95% CI 1.40-2.02) were higher in the births that received steroids compared with those that did not. These findings did not differ when examining outcomes at each gestational week of delivery between 34 weeks 0 days and 36 weeks 6 days.

CONCLUSIONS

Antenatal steroid use in late preterm births complicated with PGDM was associated with worse immediate respiratory neonatal outcomes. Our findings support current recommendations against the use of steroids in the late preterm period in pregnancies with PGDM.

The association between uterine fibroid number and size and risk of preterm birth

BACKGROUND

While the association between uterine fibroids and preterm birth is well known, data regarding whether fibroid characteristics such as number and size modify such risk are limited.

OBJECTIVE

To evaluate the association between fibroid number and size and risk of preterm birth and determine whether these characteristics impact the severity of preterm birth.

STUDY DESIGN

Multicenter retrospective cross-sectional study including all patients with singleton gestations who had at least one prenatal ultrasound at 18 0/7 weeks of gestation or later and delivered within a large university health system from January 1, 2019 to December 31, 2022. When fibroids were identified on ultrasound, their characteristics (i.e., number, size, and location) were documented. Patients with more than one delivery during the study period had only their first included for analysis. The primary outcome of preterm birth, stratified by gestational age (<37, <34, <32, and <28 weeks), was assessed based on fibroid number (1, 2, ≥3) and size (largest dimension <5 cm, 5-10 cm, >10 cm) separately in patients who had prenatally detected fibroids compared to those with no fibroids. Multivariate logistic regression was performed to adjust for potential confounders. Data were presented as adjusted odds ratios (aOR) with 95% confidence intervals (CI).

RESULTS

Among the 65,950 patients studied, 4,421 (6.7%) had at least one fibroid. The prevalence of preterm birth <37 weeks was 8.6%. The presence of any fibroid, regardless of number, was associated with an increased risk of preterm birth <37 weeks compared to no fibroids (1 fibroid: 12.8% vs. 8.2%, aOR 1.26, 95% CI 1.10-1.44; 2 fibroids: 12.7% vs. 8.2%, aOR 1.27, 95% CI 1.01-1.58; ≥3 fibroids: 18.5% vs. 8.2%, aOR 1.60, 95% CI 1.29-1.99). Patients with 2 fibroids were at increased risk of preterm birth <34, <32, and <28 weeks compared to those without fibroids, while patients with ≥3 fibroids were at increased risk of preterm birth <34 and <28 weeks compared to those without fibroids. The presence of at least one fibroid, regardless of the size of their largest dimension, was associated with an increased risk of preterm birth <37 weeks compared to no fibroids (<5 cm: 12.4% vs. 8.2%, aOR 1.19, 95% CI 1.04-1.36; 5-10 cm: 15.5% vs. 8.2%, aOR 1.47, 95% CI 1.23-1.75; >10 cm: 21.4% vs. 8.2%, aOR 2.26, 95% CI 1.55-3.28). Increasing fibroid size by largest dimension was associated with an increased risk of preterm birth <34 weeks. Patients with fibroids >10 cm by largest dimension were at increased risk of preterm birth <28 weeks compared to those without fibroids. There was no association between increasing fibroid size by largest dimension and preterm birth <32 weeks.

CONCLUSIONS

Data from this large cohort suggest that fibroid characteristics such as number and size are associated with preterm birth and impact the severity of preterm birth. Increasing fibroid number and size is associated with a higher risk of earlier preterm birth compared to those without fibroids.

Routine transabdominal cervical length screening in mid-pregnancy for the prevention of preterm birth: Is it good enough to use as a screening test?

BACKGROUND

Preterm birth (PTB) is a major pregnancy complication. There is evidence that a short cervical length in mid-pregnancy may predict women at increased risk of PTB.

AIMS

To evaluate the utility of population-based, transabdominal cervical length (TACL) measurement screening in mid-pregnancy for PTB prediction in women.

MATERIALS AND METHODS

A transabdominal approach was initially performed, with a transvaginal (TVCL) approach offered when the TACL was <35 mm, could not be accurately measured, or the pregnancy had risk factors for PTB. TACL was compared to the directly related TVCL, when both were performed at the same assessment. Women with risk factors of PTB were included when they had both TACL and TVCL measurements performed at the same visit.

RESULTS

Data were provided for 9355 singleton pregnancies from 13 participating imaging centres. A transabdominal approach was used in 9006 (96.3%), including 682 (7.3%) TVCL combined with TACL. There were 349 (3.7%) women who had TVCL only. The median TACL was longer (40 mm) than the TVCL (38 mm). In 682 paired TACL and TVCL measurements, TACL <35 mm correctly identified 96.2% of pregnancies with TVCL <25 mm, compared with 65.4% of cases when using a TACL <30 mm. A TVCL <25 mm occurred in 59 (0.6%) women. A TACL <35 mm was associated with birth <37 weeks of gestation in 12.1% of women and birth <32 weeks of gestation in 3.9%.

CONCLUSIONS

Universal TACL is a feasible option for population screening of cervical length in a low-risk population, progressing to TVCL if the TACL is <35 mm or the cervix cannot be transabdominally accurately measured.

Assessing the multifaceted cervix: examining cervical gland area at cervical length screening to predict spontaneous preterm birth

BACKGROUND

Biologically active cervical glands provide a mucous barrier while influencing the composition and biomechanical strength of the cervical extracellular matrix. Cervical remodeling during ripening may be reflected as loss of the sonographic cervical gland area. As sonographic cervical length remains suboptimal for universal screening, adjunctive evaluation of other facets of the mid-trimester cervix may impart additional screening benefit.

OBJECTIVE

To sonographically assess the cervical gland area at universal cervical length screening for preterm birth.

STUDY DESIGN

We performed a retrospective cohort study of singletons with transvaginal cervical length screening universally performed during anatomic survey between 18 0/7 and 23 6/7 weeks and subsequent live delivery at a single institution in 2018. Uterine anomalies, cerclage, suboptimal imaging, or medically indicated preterm birth were excluded. Ultrasound images were assessed for cervical length and cervical gland area (with quantitative measurements when present). The primary outcome was spontaneous preterm birth <37 weeks. Absent and present gland groups were compared using χ2, Fisher's exact, T-test, and multivariate logistic regression (adjusting for parity and progesterone use, as well as the gestational age, cervical length, and gland absence at screening ultrasound). Gland measurements were evaluated using the Mann-Whitney-U Test and Spearman's correlation.

RESULTS

Among the cohort of 772 patients, absent and present CGA groups were overall similar. Patients were on average 33 years old, ∼20 weeks gestation at screening ultrasound, and overall, 2.5% had history of prior spontaneous preterm birth. The absent gland group was more likely to have been taking progesterone (17% vs 4%, P=.04). Overall rate of preterm birth was 2.6%. However, the 2.3% of patients with absent cervical gland area were significantly more likely to deliver <37 weeks (aOR 23.9, 95% CI 6.4-89, P<.001). Multivariate logistic regression demonstrated better performance of a cervical length screening model for preterm birth prediction with the addition of qualitative gland evaluation (P<.001). Qualitative gland assessment was reproducible (PABAK 0.89), but quantitative gland measurements did not correlate with preterm birth.

CONCLUSION

Qualitative gland absence at mid-gestation cervical length screening was associated with subsequent spontaneous preterm birth, whereas quantitative gland measurements were not. Multifaceted ultrasound screening may be needed to adequately evaluate the multiple biologic functions of the cervix.

Concurrent progestogen and cerclage to reduce preterm birth: a multicenter international retrospective cohort

BACKGROUND

Both progestogens and cerclage are individually effective in preterm birth prevention in high risk pregnancies. However, national and international guidelines cite a lack of data available to comment on the potential benefit of concurrent progestogen therapy after cerclage has been placed. Studies to date have been small with mixed results regarding benefit of concurrent progestogen with cerclage leaving uncertainty regarding best clinical practice.

OBJECTIVE

This study aimed to evaluate whether cerclage with progestogen therapy was superior to cerclage alone in the prevention of spontaneous preterm birth in singleton pregnancies.

METHODS

This is an international retrospective cohort study of singleton pregnancies, without major anomaly or aneuploidy, and with cerclage placed at 10 different institutions in the United States and Colombia from June 2016 to June 2020. Exclusion criteria were lack of documentation regarding whether progestogen was prescribed, unavailable delivery outcome, and pregnancy termination (spontaneous or induced) before 16 weeks' gestation. The exposure of interest was progestogen use with cerclage placement, which included those who continued to use progestogen or who started progestogen after cerclage. The comparison group consisted of those without progestogen use after cerclage placement, which included those who had no progestogen use during the entire pregnancy or who initiated progestogen and then stopped it after cerclage placement. Progestogen type, cerclage indication, maternal baseline characteristics, and maternal/neonatal outcomes were collected. The primary outcome was spontaneous preterm birth at <37 weeks. The secondary outcomes were spontaneous preterm birth at <34 weeks, gestational age at delivery, and a composite neonatal outcome including ≥1 of the following: perinatal mortality, confirmed sepsis, grade III or IV intraventricular hemorrhage, retinopathy of prematurity, respiratory distress syndrome, and bronchopulmonary dysplasia. There were planned subgroup analyses by cerclage indication, progestogen type (vaginal progesterone vs 17-hydroxyprogesterone caproate), preterm birth history, and site. Continuous variables were compared in adjusted analyses with analysis of covariance, and categorical variables were compared with multivariable logistic regression, adjusting for potential confounders with adjusted odds ratio. A Cox regression survival curve was generated to compare latency to spontaneous delivery, censored after 37 weeks.

RESULTS

During the study period, a total of 699 singletons met the inclusion criteria: 561 in the progestogen with cerclage group and 138 with cerclage alone. Baseline characteristics were similar, except the higher likelihood of previous spontaneous preterm birth in the progestogen group (61% vs 41%; P<.001). Within the progestogen group, 52% were on 17-hydroxyprogesterone caproate weekly, 44% on vaginal progesterone daily, and 3% on oral progesterone daily. Progestogen with cerclage was associated with a significantly lower frequency of spontaneous preterm birth <37 weeks (31% vs 39%; adjusted odds ratio, 0.59 [0.39-0.89]; P=.01) and <34 weeks (19% vs 27%; adjusted odds ratio, 0.55 [0.35-0.87]; P=.01), increased latency to spontaneous delivery (hazard ratio for spontaneous preterm birth <37 weeks, 0.66 [0.49-0.90]; P=.009), and lower frequency of perinatal death (7% vs 16%; adjusted odds ratio, 0.37 [0.20-0.67]; P=.001). In planned subgroup analyses, association with reduced odds of preterm birth <37 weeks persisted in those on vaginal progesterone, those without a previous preterm birth, those with ultrasound- or examination-indicated cerclage, those who started progestogen therapy before cerclage, and in sites restricted to the United States.

CONCLUSION

Use of progestogen with cerclage was associated with reduced rates of spontaneous preterm birth and early spontaneous preterm birth compared with cerclage alone. Although this study was not sufficiently powered for subgroup analysis, the strength of evidence for benefit appeared greatest for those with ultrasound- or examination-indicated cerclage, and with vaginal progesterone. El resumen está disponible en Español al final del artículo.

The utility of combined utero-cervical ındex in predicting preterm delivery in pregnant women with preterm uterine contractions

PURPOSE

To evaluate the utility of a novel ultrasound index "combined utero-cervical index (CUCI)" in the prediction of preterm delivery.

METHODS

The present prospective cohort study was conducted in Ankara Bilkent City Hospital Perinatology Clinic between January 1, 2023, and March 31, 2023. Pregnant women with uterine contractions between 24 and 36th gestational weeks but did not have dilatation or effacement were included. CUCI was calculated as: (utero-cervical angle)/(anterior cervical lip thickness + fundal thickness + lower uterine segment thickness + cervical length). In the presence of cervical funneling, one point was added to the final result. A ROC analysis was conducted to determine the potential of CUCI in predicting delivery <37 weeks of gestation, <34 weeks of gestation, and <4 weeks after the first admission to the hospital for uterine contractions, respectively.

RESULTS

Optimal cut-off values of CUCI were found to be 1.4 (67.1% sensitivity, 67.2% specificity) for predicting delivery at <37th weeks, 1.7 (72.7% sensitivity, 65.7% specificity) for predicting delivery at <34th weeks, and 1.4 (62.5% sensitivity, 61.7% specificity) for predicting delivery at <4 weeks.

CONCLUSION

CUCI may be used in the prediction of preterm delivery for pregnant women admitted to hospital with preterm uterine contractions.

Racial and Ethnic Disparities in Cervical Insufficiency, Cervical Cerclage, and Preterm Birth

Background: The frequency of cervical insufficiency differs among the major racial and ethnic groups, with limited data specific to Asian American and Native Hawaiian/Pacific Islander (AANHPI) subpopulations. We assessed cervical insufficiency diagnoses and related outcomes across 10 racial and ethnic groups, including disaggregated AANHPI subgroups, in a large population-based cohort. Study Design: We performed a retrospective cohort study of all singleton births between 20-42 weeks' gestation in California from 2007 to 2018. Logistic regression models were performed to estimate the odds of cervical insufficiency and, among people with cervical insufficiency, the odds of cerclage and preterm birth according to self-reported race and ethnicity. Results: Among 5,114,470 births, 38,605 (0.8%) had a diagnosis code for cervical insufficiency. Compared with non-Hispanic White people, non-Hispanic Black people had the highest odds of cervical insufficiency (adjusted odds ratio [aOR] 3.07; 95% confidence interval [CI], 2.97, 3.18), for cerclage placement and higher odds for preterm birth. Disaggregating AANHPI subgroups showed that Indian people had the highest odds (aOR 1.94; 95% CI, 1.82, 2.07) of cervical insufficiency and had significantly higher odds of cerclage without increased odds of preterm birth; Southeast Asian people had the highest odds of preterm birth. Conclusion: Within a large, diverse population-based cohort, non-Hispanic Black people experienced the highest rates of cervical insufficiency, and among those with cervical insufficiency, had among the highest rates of cerclage and preterm birth. Among AANHPI subgroups specifically, Indian people had the highest rates of cervical insufficiency and cerclage placement, without increased rates of preterm birth; Southeast Asian people had the highest rates of preterm birth, without increased rates of cerclage. Disaggregating AANHPI subgroups identifies important differences in obstetric risk factors and outcomes.

The vaginal immunoproteome for the prediction of spontaneous preterm birth: A retrospective longitudinal study

Background

Preterm birth is the leading cause of neonatal morbidity and mortality worldwide. Most cases of preterm birth occur spontaneously and result from preterm labor with intact (spontaneous preterm labor [sPTL]) or ruptured (preterm prelabor rupture of membranes [PPROM]) membranes. The prediction of spontaneous preterm birth (sPTB) remains underpowered due to its syndromic nature and the dearth of independent analyses of the vaginal host immune response. Thus, we conducted the largest longitudinal investigation targeting vaginal immune mediators, referred to herein as the immunoproteome, in a population at high risk for sPTB.

Methods

Vaginal swabs were collected across gestation from pregnant women who ultimately underwent term birth, sPTL, or PPROM. Cytokines, chemokines, growth factors, and antimicrobial peptides in the samples were quantified via specific and sensitive immunoassays. Predictive models were constructed from immune mediator concentrations.

Results

Throughout uncomplicated gestation, the vaginal immunoproteome harbors a cytokine network with a homeostatic profile. Yet, the vaginal immunoproteome is skewed toward a pro-inflammatory state in pregnant women who ultimately experience sPTL and PPROM. Such an inflammatory profile includes increased monocyte chemoattractants, cytokines indicative of macrophage and T-cell activation, and reduced antimicrobial proteins/peptides. The vaginal immunoproteome has improved predictive value over maternal characteristics alone for identifying women at risk for early (<34 weeks) sPTB.

Conclusions

The vaginal immunoproteome undergoes homeostatic changes throughout gestation and deviations from this shift are associated with sPTB. Furthermore, the vaginal immunoproteome can be leveraged as a potential biomarker for early sPTB, a subset of sPTB associated with extremely adverse neonatal outcomes.

Funding

This research was conducted by the Perinatology Research Branch, Division of Obstetrics and Maternal-Fetal Medicine, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, U.S. Department of Health and Human Services (NICHD/NIH/DHHS) under contract HHSN275201300006C. ALT, KRT, and NGL were supported by the Wayne State University Perinatal Initiative in Maternal, Perinatal and Child Health.

Perinatal Outcomes Associated With the Modified Shirodkar Cervical Cerclage Technique

OBJECTIVE

The objective of this study was to describe demographic and clinical characteristics and surgical and neonatal results related to the modified Shirodkar cervical cerclage technique.

MATERIALS AND METHODS

This was an observational descriptive and retrospective study. Data was called from anonymized medical records of women who were pregnant and diagnosed with cervical incompetence and who had also undergone cervical cerclage procedures using the modified Shirodkar technique. The variables recorded included demographics such as the maternal age of patients, clinical features like obstetric history, physical examination, and ultrasound findings, and surgical and neonatal outcomes. The qualitative variables were processed using frequencies and percentages, and the quantitative variables were obtained through median, interquartile range, mean, and standard deviation.

RESULTS

Our study included 39 anonymized medical records. The main indication for cervical cerclage placement was prophylactic (56%). The median gestational age at cerclage placement was 16 weeks, with a median gestational age at birth of 38 weeks; only 13% had complications related to prematurity, and 5% were admitted to the neonatal intensive care unit.

CONCLUSION

The modified Shirodkar technique is associated with favorable surgical, maternal, and neonatal outcomes.

Predicting Preterm Birth Using Cell-Free Ribonucleic Acid

Spontaneous preterm birth (sPTB) is a complex and clinically heterogeneous condition that remains incompletely understood, leading to insufficient interventions to effectively prevent it from occurring. Cell-free ribonucleic acid signatures in the maternal circulation have the potential to identify biologically relevant subtypes of sPTB. These could one day be used to predict and prevent sPTB in asymptomatic individuals, and to aid in prognosis and management for individuals presenting with threatened preterm labor and preterm prelabor rupture of membranes.

Use and Impact of Pessary, Cerclage, and Progesterone for the Secondary Prevention of Preterm Birth: Data from the German Neonatal Network

BACKGROUND

To evaluate the use and effect of cervical stitch cerclage, pessary, and progesterone on pregnancy outcome in mothers of very low birth weight infants (VLBWI) born<32 weeks of gestation in the German Neonatal Network (GNN).

METHODS

The GNN is a population-based cohort study enrolling VLBWI since 2009. We included 575 neonates from 424 mothers into our analysis, who were born between 2015 and 2019, after prenatal intervention with cerclage, pessary, progesterone or a combination between 20/0 to 25/0 weeks of gestation to prevent preterm birth. Median intervention-to-birth interval was the primary endpoint.

RESULTS

231 of 424 pregnant women had a cerclage only (54.5%), 76 women a pessary only (17.9%), and 27 were prescribed progesterone only (15.3%). The most common combination treatment (>1 intervention group) was cerclage plus progesterone (n=27), followed by cerclage plus pessary (n=13). The median intervention-to-birth interval for the whole cohort was 24 days (IQR 19.0 days). The earlier the intervention was started, the longer the intervention-to-birth interval lasted: When started at 20 weeks, the interval was 34 days in contrast to 11.5 days, when started at 25 weeks. The >1 group was born at a significantly higher median GA with 27.0 weeks (IQR 2.9 weeks) and a higher median birth weight of 980 g (IQR 394 g) accordingly.

CONCLUSION

We propose that the earliest possible start of intervention leads to the most efficient pregnancy prolongation.

CX3CL1/Fractalkine as a biomarker for early pregnancy prediction of preterm premature rupture of membranes

OBJECTIVES

The objective of our study was to evaluate serum CX3CL1/Fractalkine, a monocyte/macrophage chemoattractant expressed in cytotrophoblasts and decidual cells, as a predictive biomarker for the occurrence of preterm premature rupture of membranes (PPROM).

METHODS

A case-control study of 438 pregnancies including 82 PPROM cases and 64 preterm labor with intact membranes cases with blood samples collected at first trimester, second trimester and delivery was conducted. The predictive ability of CX3CL1 and maternal risk factors for the occurrence of PPROM was assessed by receiver operating characteristic curve analysis. A second, independent cohort was prospectively constituted to confirm the case-control study results.

RESULTS

First trimester CX3CL1 was significantly increased in PPROM cases when compared to matched controls. Multivariate regression analysis highlighted a significant difference for CX3CL1 measured during the first trimester (p<0.001). Alone, CX3CL1 predicts PPROM with a 90 % sensitivity and a specificity around 40 %. The area under the receiver operating characteristic curve for PPROM prediction were 0.64 (95% confidence interval: 0.57-0.71) for first trimester CX3CL1, and 0.61 (95% confidence interval: 0.54-0.68) for maternal risk factors (body mass index<18.5 kg/m2, nulliparity, tobacco use and the absence of high school diploma). The combination of CX3CL1 and maternal risk factors significantly improved the area under the curve: 0.72 (95% confidence interval: 0.66-0.79) (p<0.001). The results were confirmed on a second independent cohort.

CONCLUSIONS

CX3CL1 is a promising blood biomarker in the early (first trimester) prediction of PPROM.

Predictive Factors for the Common Adverse Maternal and Fetal Outcomes in Pregnancies Complicated by Systemic Lupus Erythematosus

Objectives

This study aimed to evaluate the outcomes of pregnancy in patients with systemic lupus erythematosus (SLE). It focused on identifying clinical and laboratory markers that could predict the common adverse pregnancy outcomes (APOs) after 20 weeks of gestation, namely preeclampsia (PE) and preterm birth (PTB) in them.

Methods

Pregnant SLE women who delivered at the study center from 2010 to 2023 were retrospectively analyzed. Categorical variables were evaluated using the chi-square test or Fisher's exact test, while continuous variables underwent Mann-Whitney U testing. Stepwise regression was used to assess the predictors of pregnancy outcomes.

Results

The study enrolled 445 pregnancies in 408 women diagnosed with SLE. Of these, 202 pregnancies (45.4%) resulted in at least one APO. Disease flare-ups, hypertension, and proteinuria during the first trimester were primary predictors of at least one APO and PTB. The most frequently recorded maternal adverse outcome was PE (14.6%), while PTB accounted for 32.6% of fetal adverse outcomes. Multivariate regression analysis identified hypertension, history of PE, associated antiphospholipid syndrome (APS), proteinuria, and low serum C4 in the first trimester as independent risk factors for PE. Regular follow-ups at our center correlated with lower risks of APOs, PE, and PTB. APS also emerged as a risk factor for PTB, whereas the use of hydroxychloroquine (HCQ) during pregnancy seemed to protect against PTB.

Conclusion

For pregnancies complicated by SLE, we recommend early pregnancy screening for proteinuria-even in the absence of lupus nephritis-as well as continued use of HCQ and routine prenatal care throughout pregnancy.

The frequency-following response in late preterm neonates: a pilot study

Introduction

Infants born very early preterm are at high risk of language delays. However, less is known about the consequences of late prematurity. Hence, the aim of the present study is to characterize the neural encoding of speech sounds in late preterm neonates in comparison with those born at term.

Methods

The speech-evoked frequency-following response (FFR) was recorded to a consonant-vowel stimulus /da/ in 36 neonates in three different groups: 12 preterm neonates [mean gestational age (GA) 36.05 weeks], 12 "early term neonates" (mean GA 38.3 weeks), and "late term neonates" (mean GA 41.01 weeks).

Results

From the FFR recordings, a delayed neural response and a weaker stimulus F0 encoding in premature neonates compared to neonates born at term was observed. No differences in the response time onset nor in stimulus F0 encoding were observed between the two groups of neonates born at term. No differences between the three groups were observed in the neural encoding of the stimulus temporal fine structure.

Discussion

These results highlight alterations in the neural encoding of speech sounds related to prematurity, which were present for the stimulus F0 but not for its temporal fine structure.

Is the Risk of Intrahepatic Cholestasis Increased with Supplemental Progesterone?

OBJECTIVE

 This study aimed to evaluate the relationship between supplemental progesterone use during pregnancy and the development of intrahepatic cholestasis of pregnancy (ICP).

STUDY DESIGN

 A retrospective, matched case-control study was conducted among a population of women who delivered at George Washington University Hospital (GW) between 2012 and 2022. Women diagnosed with ICP (cases) were identified using International Statistical Classification of Diseases (ICD) codes, and data were collected via chart abstraction. Descriptive data included patient demographics, pregnancy characteristics, and medical history. Laboratory values related to ICP were collected. Cases were matched on a 1:3 ratio by maternal age, body mass index, and gravidarum to women who delivered at GW during the same month and did not carry a diagnosis of ICP (controls). A univariate logistic regression model was created to assess the use of supplemental progesterone between groups, adjusting for the use of assisted reproductive technology in the current pregnancy, and a history of liver disease.

RESULTS

 One hundred and twenty women who delivered during the study period were confirmed to have a diagnosis of ICP. Cases were matched with 360 controls and measures compared between the two groups. Cases were significantly more likely to have a history of liver disease (5.9 vs. 1.7%, p = 0.0021), multiple gestation (10.0 vs. 3.3%, p < 0.0001), a history of ICP in a previous pregnancy (10.0 vs. 0%, p < 0.0001), and to have delivered at an earlier gestational age (mean 37.1 vs. 38.6 weeks, p < 0.0001) as compared with controls. No differences were seen in the odds of supplemental progesterone use in both unadjusted and adjusted models (OR 1.14, 95% CI 0.30-4.34; adjusted Odds Ratio [aOR] 0.98 0.24-3.94).

CONCLUSION

 Contrary to recent evidence, no association was seen with the use of supplemental progesterone. It is possible that the associated risk with supplemental progesterone is dependent on medication formulation or route of administration.

KEY POINTS

· Supplemental progesterone use in pregnancy may increase the risk of developing ICP.. · Previous investigations of progesterone and ICP have demonstrated mixed results.. · The association may be dependent on the route of administration and formulation of progesterone..

Universal cervical length screening and risk of spontaneous preterm birth: a systematic review and meta-analysis

OBJECTIVE

To evaluate the risk of spontaneous preterm birth with or without universal transvaginal ultrasound cervical length screening at the time of midtrimester scan.

DATA SOURCES

Medline, Embase, ClinicalTrials.gov, and Web of Science were systematically searched from the inception of the databases to November 12, 2023, using combinations of the relevant medical subject heading terms, key words, and word variants that were considered suitable for the topic.

STUDY ELIGIBILITY CRITERIA

Studies including individuals with singleton gestations at 16-25 weeks of gestation screened or not screened with universal transvaginal ultrasound cervical length screening were considered eligible. Primary outcome was spontaneous preterm birth <37 weeks; secondary outcomes were spontaneous preterm birth <34 and <32 weeks.

METHODS

Random effect head-to-head analyses were used to directly compare each outcome, expressing the results as summary odds ratio and relative 95% confidence interval. The quality of the included studies was independently assessed by 2 reviewers, using the Newcastle-Ottawa scale for cohort studies and the Cochrane risk-of-bias tool for randomized controlled studies. The study was registered on the prospective register of systematic reviews database (PROSPERO) (registration number: CRD42022385325).

RESULTS

Eight studies, including 447,864 pregnancies, were included in the meta-analysis (213,064 screened with transvaginal ultrasound cervical length and 234,800 unscreened). In the overall analysis, universal transvaginal ultrasound cervical length did not significantly decrease the spontaneous preterm birth rates <37 weeks (odds ratio, 0.92 [95% confidence interval, 0.84-1.01], P=.07) and <34 weeks (odds ratio, 0.87 [95% confidence interval, 0.73-1.04], P=.12), but was significantly associated with a lower risk of spontaneous preterm birth <32 weeks (odds ratio, 0.84 [95% confidence interval, 0.76-0.94], P=.002). Individuals without a prior spontaneous preterm birth had a significantly lower risk of spontaneous preterm birth <37 weeks (odds ratio, 0.88 [95% confidence interval, 0.79-0.97], P=.01) and a lower trend of spontaneous preterm birth <32 weeks (odds ratio, 0.82 [95% confidence interval, 0.66-1.01], P=.06) when screened with transvaginal ultrasound cervical length, compared with no screening.

CONCLUSION

Universal transvaginal ultrasound cervical length screening usually <24 weeks in singletons without a prior spontaneous preterm birth, is associated with a significant reduction in spontaneous preterm birth <37 weeks, compared with no screening.

Evaluating the Efficacy of Cervical Tactile Ultrasound Technique as a Predictive Tool for Spontaneous Preterm Birth

Background

Premature cervical softening and shortening may be considered an early mechanical failure that predispose to preterm birth.

Purpose

This study aims to explore the applicability of an innovative cervical tactile ultrasound approach for predicting spontaneous preterm birth (sPTB).

Materials and Methods

Eligible participants were women with low-risk singleton pregnancies in their second trimester, enrolled in this prospective observational study. A Cervix Monitor (CM) device was designed with a vaginal probe comprising four tactile sensors and a single ultrasound transducer operating at 5 MHz. The probe enabled the application of controllable pressure to the external cervical surface, facilitating the acquisition of stress-strain data from both anterior and posterior cervical sectors. Gestational age at delivery was recorded and compared against cervical elasticity.

Results

CM examination data were analyzed for 127 women at 240/7 - 286/7 gestational weeks. sPTB was observed in 6.3% of the cases. The preterm group exhibited a lower average cervical stress-to-strain ratio (elasticity) of 0.70 ± 0.26 kPa/mm compared to the term group's 1.63 ± 0.65 kPa/mm with a p-value of 1.1 × 10-4. Diagnostic accuracy for predicting spontaneous preterm birth based solely on cervical elasticity data was found to be 95.0% (95% CI, 88.5 - 100.0).

Conclusion

These findings suggest that measuring cervical elasticity with the designed tactile ultrasound probe has the potential to predict spontaneous preterm birth in a cost-effective manner.

Successful multidisciplinary team management of placenta accreta spectrum disorder: A referral center model in a middle-income country

OBJECTIVE

The aim of the study was to evaluate the outcomes of placenta accreta spectrum (PAS) disorder managed by a multidisciplinary care team (MCT) compared with a conventional care team (CCT) in a PAS referral center in Thailand.

METHODS

This retrospective single-center cohort study analyzed PAS management outcomes in the PSU PAS Center between January 2010 and December 2022. The incidence of hemorrhage ≥3500 mL and the composite maternal and neonatal outcomes of PAS were compared before and after the introduction of an MCT in 2016.

RESULTS

Of 227 PAS cases, 219 (96.5%) had pathological confirmation. There were 52 (22.9%) cases of placenta accreta, 119 (52.4%) cases of placenta increta, and 56 (24.7%) cases of placenta percreta. The incidence of estimated blood loss (EBL) ≥3500 mL decreased from 61.8% to 34.3% (P < 0.001) after the establishment of the MCT. The median EBL decreased from 4000 (IQR: 2600,7250) mL to 2250 (1300, 4750) mL (P < 0.001). EBL reduction was statistically significant in the accreta and increta groups (P < 0.001). Red blood cell transfusions decreased from five (3, 9) to two (1, 6) units (P < 0.001) per patient. The length of maternal hospital stays and ICU admissions were statistically shorter when PAS was managed by an MCT (P < 0.001). The length of newborn hospital and ICU stays decreased significantly (P < 0.001).

CONCLUSION

The incidence of massive postpartum hemorrhage and a composite of maternal and neonatal morbidities in pregnant women with PAS disorder improved significantly after the establishment of an MCT to manage PAS in a middle-income country setting.

Predictors of Breastfeeding among Patients Admitted with Preterm Prelabor Rupture of Membranes

OBJECTIVE

 We sought to describe rates of breastmilk feeding (BF) at hospital discharge and 6 weeks postpartum and to identify risk factors for noninitiation or cessation among pregnancies complicated by preterm prelabor rupture of membranes (PPROM).

STUDY DESIGN

 Retrospective cohort study of pregnant persons with PPROM admitted to a single tertiary center (2013-2019). Patients with deliveries complicated by intrauterine or neonatal demise or with incomplete BF data were excluded. Demographic, antepartum, and delivery characteristics were evaluated. Primary analysis identified rate of BF initiation at maternal discharge and factors associated with noninitiation. Secondary analysis evaluated BF continuation and factors associated with cessation at 6 weeks postpartum. Bivariate statistics were used to compare characteristics and logistic regression was used to estimate adjusted odds ratios (aOR).

RESULTS

 Of 397 patients with PPROM, 342(86%) initiated BF prior to discharge. Those reporting tobacco use in pregnancy were less likely to initiate BF (aOR: 0.32; 95% confidence interval [CI]: 0.16, 0.64). In contrast, private insurance (aOR: 2.53; 95% CI: 1.19, 5.37) and pregnancy latency ≥ 14 days (aOR: 3.02; 95% CI: 1.09, 8.38) were associated with BF initiation at hospital discharge. Of the 293 patients with postpartum follow-up, only 214 (73%) had BF continuation at 6 weeks postpartum. Maternal age <20 years (aOR: 0.07; 95% CI: 0.01, 0.68) and multiparity (aOR: 0.54; 95% CI: 0.29, 0.99) were associated with BF cessation. Patients with private insurance were observed to have increased odds of BF continuation (aOR: 2.10; 95% CI: 1.07, 4.12).

CONCLUSION

 Among patients with PPROM, tobacco use may be associated with noninitiation of BF prior to discharge, whereas age < 20 years and multiparity were associated with cessation by 6 weeks postpartum. Longer pregnancy latency ≥ 14 days was associated with BF initiation prior to discharge. Private insurance was associated with increased rates of BF initiation and continuation postpartum. BF education and support should be offered to all patients admitted for PPROM.

KEY POINTS

· Tobacco use may be associated with BF noninitiation.. · Young age and multiparity are linked with BF cessation.. · Private insurance resulted in BF initiation and continuation..

Nationwide status of progestogen treatment to prevent spontaneous preterm birth: A questionnaire survey for childbirth healthcare facilities in Japan

AIM

This study aimed to investigate the current status of progestogen treatment for pregnant women at a high risk for preterm birth (PTB) in childbirth healthcare facilities in Japan.

METHODS

A web-based nationwide questionnaire survey regarding progestogen use for prevention of PTB was conducted among childbirth healthcare facilities from 2019 to 2021.

RESULTS

Valid responses were obtained from 528 facilities (25.2% of those surveyed), including 155 tertiary perinatal facilities (making up 92.3% of all tertiary perinatal care facilities). In the survey period, progestogen treatment was implemented in 207 facilities (39.2%) for PTB prevention. Regarding types of progestogens, 17α-hydroxyprogesterone caproate was used in 170 facilities (82.1%), with a low dose (125 mg/week) administered in 62.9% of the facilities to comply with the regulations of the national health insurance system, although 250 mg/week is considered the best dose. Vaginal progesterone was used in 36 facilities (17.4%), although the cost of vaginal progesterone was not covered by health insurance. Of the facilities not administering progestogen treatment, approximately 40% expressed that vaginal progesterone would be their first choice for PTB prevention in daily practice if it would be covered by health insurance in the future.

CONCLUSIONS

Due to the current regulations of the Japanese health insurance system, 17α-hydroxyprogesterone caproate, rather than vaginal progesterone, was mainly used for PTB prevention. Despite global evidence supporting vaginal progesterone as the approach with the highest efficacy, only a limited number of facilities have utilized it due to the current drug use regulations in Japan.

The Role of Cerclage in Subsequent Pregnancy following Previable Prelabor Rupture of Membranes

OBJECTIVE

This study aimed to ascertain the outcomes associated with a cervical cerclage among individuals with a history of previable prelabor rupture of membranes (PROM).

STUDY DESIGN

This study was a retrospective cohort study conducted at a single tertiary center between 2011 and 2021. We included individuals with a history of previable (before 24 weeks) PROM and the subsequent viable pregnancy. Women with multifetal gestation, preterm birth (PTB) or cerclage in previous gestation, or abdominal cerclage after trachelectomy were excluded. Primary outcome was PTB rate (delivery <37 weeks). Recurrence of preterm PROM and adverse composite maternal and neonatal outcomes (CMO and CNO) were evaluated as secondary outcomes. CMO included any of the following: suspected chorioamnionitis, endometritis, red blood cell transfusion, uterine rupture, unplanned hysterectomy, or death. CNO included any of the following: previable PTB (<24 weeks of gestation), bronchopulmonary dysplasia, grade 3 or 4 intraventricular hemorrhage, necrotizing enterocolitis, mechanical ventilation, seizures, hypoxic ischemic encephalopathy, or death.

RESULTS

During the study period, 118 individuals had a history of previable PROM and a documented subsequent pregnancy, out of which 74 (62.7%) met inclusion criteria. Nineteen (25.7%) of eligible individuals underwent a cerclage for prior previable PROM and were compared with controls (n = 55, 74.3%). Women who underwent a cerclage had higher rates of PTB < 37 weeks (63.2 vs. 10.9%, p < 0.001; odds ratio [OR]: 14.00, 95% confidence interval [CI]: 3.97-49.35) and < 34 weeks (21.1 vs. 3.6%, p = 0.03; OR: 7.07, 95% CI: 1.18-42.39) compared with those without cerclage. Furthermore, recurrent preterm PROM and previable PTB rates were higher among patients who underwent cerclage. The survival curve further indicated that individuals with cerclage delivered earlier. CMO and CNO rates were similar in those with and without cerclage.

CONCLUSION

Cerclage placement in individuals with prior previable PROM was associated with higher rates of recurrent preterm PROM and PTB.

KEY POINTS

· The management of individuals in a subsequent pregnancy following previable PROM is a conundrum.. · Cerclage following previable PROM is associated with higher rates of recurrent preterm PROM and PTB.. · Composite maternal and neonatal outcome rates were similar in those with and without cerclage..

Contractions of the lower uterine segment during transvaginal ultrasound cervical length: incidence, significance, proper measurement, and management

An accurate transvaginal ultrasound cervical length is paramount to obtain the best prediction for preterm birth. Transvaginal ultrasound cervical length should be optimally obtained when a lower uterine segment contraction is not seen. For universal transvaginal ultrasound cervical length screening at approximately 20 weeks of gestation, the options are to do the transvaginal ultrasound soon after bladder void (lower uterine segment contractions present in 16%-43% of this approach) or to wait until the end of the anatomy scan (ideally within 30 minutes after bladder voiding) to decrease the chance of a lower uterine segment contraction. If the lower uterine segment contraction persists even after waiting up to 20 minutes or more, only the true transvaginal ultrasound cervical length should be reported. In particular, in patients with a previous spontaneous preterm birth, if the lower uterine segment contraction persists, the transvaginal ultrasound cervical length can be repeated in ≤7 days even in the presence of a normal (>25 mm) cervical length. Similar to a blood pressure cuff that must be of the right size for proper blood pressure measurement and a glucometer that must be properly calibrated, screening with transvaginal ultrasound cervical length should only be performed following a proper and standardized technique, including avoiding as much as feasible the presence of lower uterine segment contractions.

Ureaplasma and Mycoplasma Screening for Pregnant Individuals Who Are at High Risk for Preterm Birth

OBJECTIVE

This study aimed to examine gestational age at delivery according to Ureaplasma/Mycoplasma cervical culture results and whether pregnant individuals received antibiotics.

STUDY DESIGN

A retrospective cohort study at a single academic institution where all pregnant individuals with risk factors for preterm birth including those with a history of preterm birth, recurrent pregnancy loss, or pregnancy requiring cervical cerclage were included. We plotted Kaplan-Meier curves to investigate the association between the gestational age at delivery and Ureaplasma culture results (negative; positive and treated; or positive but did not receive the treatment). A Cox proportional regression model was used to calculate hazard ratio (HR) with 95% confidence intervals (95% CI), controlling for confounders. The main outcome was age at delivery. Analyses were repeated for Mycoplasma culture.

RESULTS

Of 607 individuals, 258 (42.5%) had a negative Ureaplasma culture, 308 (50.7%) had a positive Ureaplasma culture and received treatment, and 41 (6.8%) had a positive Ureaplasma culture and did not receive treatment. Compared with those who had a positive Ureaplasma culture but did not receive treatment, those who had a negative Ureaplasma culture did not have a decreased risk (HR: 1.03; 95% CI: 0.74-1.44). Compared with those who had a positive Ureaplasma culture but did not receive treatment, those who had a positive Ureaplasma culture and received treatment did not have a decreased risk (HR: 0.91; 95% CI: 0.66-1.27). The treatment failure rate of Ureaplasma after treatment was 78.6% (95% CI: 72.8-83.7%). Overall, the findings of Mycoplasma were similar.

CONCLUSION

Routine ureaplasma/mycoplasma cervical culture is not recommended for pregnant individuals who are at high risk for preterm birth.

KEY POINTS

· Ureaplasma/mycoplasma species are isolated in patients with preterm birth.. · High ureaplasma/mycoplasma recurrence rate despite treatment with antibiotics.. · Treatment of patient and partner did not improve gestational age at delivery..

High rates of placental inflammation among samples collected by the Multi-Omics for Mothers and Infants consortium

BACKGROUND

The Multi-Omics for Mothers and Infants consortium aims to improve birth outcomes. Preterm birth is a major obstetrical complication globally and causes significant infant and childhood morbidity and mortality.

OBJECTIVE

We analyzed placental samples (basal plate, placenta or chorionic villi, and the chorionic plate) collected by the 5 Multi-Omics for Mothers and Infants sites, namely The Alliance for Maternal and Newborn Health Improvement Bangladesh, The Alliance for Maternal and Newborn Health Improvement Pakistan, The Alliance for Maternal and Newborn Health Improvement Tanzania, The Global Alliance to Prevent Prematurity and Stillbirth Bangladesh, and The Global Alliance to Prevent Prematurity and Stillbirth Zambia. The goal was to analyze the morphology and gene expression of samples collected from preterm and uncomplicated term births.

STUDY DESIGN

The teams provided biopsies from 166 singleton preterm (<37 weeks' gestation) and 175 term (≥37 weeks' gestation) deliveries. The samples were fixed in formalin and paraffin embedded. Tissue sections from these samples were stained with hematoxylin and eosin and subjected to morphologic analyses. Other placental biopsies (n=35 preterm, 21 term) were flash frozen, which enabled RNA purification for bulk transcriptomics.

RESULTS

The morphologic analyses revealed a surprisingly high rate of inflammation that involved the basal plate, placenta or chorionic villi, and the chorionic plate. The rate of inflammation in chorionic villus samples, likely attributable to chronic villitis, ranged from 25% (Pakistan site) to 60% (Zambia site) of cases. Leukocyte infiltration in this location vs in the basal plate or chorionic plate correlated with preterm birth. Our transcriptomic analyses identified 267 genes that were differentially expressed between placentas from preterm vs those from term births (123 upregulated, 144 downregulated). Mapping the differentially expressed genes onto single-cell RNA sequencing data from human placentas suggested that all the component cell types, either singly or in subsets, contributed to the observed dysregulation. Consistent with the histopathologic findings, gene ontology analyses highlighted the presence of leukocyte infiltration or activation and inflammatory responses in both the fetal and maternal compartments.

CONCLUSION

The relationship between placental inflammation and preterm birth is appreciated in developed countries. In this study, we showed that this link also exists in developing geographies. In addition, among the participating sites, we found geographic- and population-based differences in placental inflammation and preterm birth, suggesting the importance of local factors.

Preterm birth, a consequence of immune deviation mediated hyperinflammation

Preterm birth represents a multifaceted syndrome with intricacies still present in our comprehension of its etiology. In the context of a semi-allograft, the prosperity from implantation to pregnancy to delivery hinges on the establishment of a favorable maternal-fetal immune microenvironment and a successful trilogy of immune activation, immune tolerance and then immune activation transitions. The occurrence of spontaneous preterm birth could be related to abnormalities within the immune trilogy, stemming from deviation in maternal and fetal immunity. These immune deviations, characterized by insufficient immune tolerance and early immune activation, ultimately culminated in an unsustainable pregnancy. In this review, we accentuated the role of both innate and adaptive immune reason in promoting spontaneous preterm birth, reviewed the risk of preterm birth from vaginal microbiome mediated by immune changes and the potential of vaginal microbiomes and metabolites as a new predictive marker, and discuss the changes in the role of progesterone and its interaction with immune cells in a preterm birth population. Our objective was to contribute to the growing body of knowledge in the field, shedding light on the immunologic reason of spontaneous preterm birth and effective biomarkers for early prediction, providing a roadmap for forthcoming investigations.

Hepatitis C Prevalence and Birth Outcomes among Pregnant Women in the United States: A 2010-2020 Population Study

BACKGROUND

The rates of hepatitis C virus (HCV) infection have increased in the pregnant population. We aim to describe the age-stratified clinical outcomes and trends for inpatient pregnant women with HCV in the U.S.

METHODS

We utilized hospitalization data from the 2010-2020 National Inpatient Sample. Pregnancy and HCV were identified according to their ICD-9/ICD-10 codes. Demographic and clinical data including cirrhosis, mortality, preterm birth, and stillbirth were extracted. The age groups were defined as ≤18, 19-25, 26-34, and ≥35 years.

RESULTS

We identified 195,852 inpatient pregnant women with HCV, among whom 0.7% were ≤18, 26.7% were 19-25, 57.9% were 26-34, and 14.8% were ≥35 years of age. The hospitalization rates of pregnant women with HCV increased overall between 2010 and 2020, with the highest velocity in the 26-34 age group. The 26-34 age group had the highest HCV burden, with an age-standardized hospitalization rate of 660 per 100,000 in 2020. The rates of mortality and cirrhosis were significantly higher in the HCV cohort and increased further with age (p < 0.05). Among the HCV pregnant cohort, 151,017 (77.1%) delivered during hospitalization. Preterm births and stillbirths were significantly higher in the HCV pregnant cohort compared to the controls across multiple age groups (p < 0.05). Minority race/ethnicity was associated with increased mortality, cirrhosis, preterm birth, and stillbirth (p < 0.001). HIV co-infection, hepatitis B co-infection, and diabetes increased the odds of cirrhosis (p < 0.001).

CONCLUSIONS

Hospitalizations of pregnant women with HCV are escalating, and these women are at increased risk of mortality, cirrhosis, preterm birth, and stillbirth with modifying factors, exacerbating risks further.

Progesterone therapy for prevention of recurrent spontaneous preterm birth in a minority patient population: a retrospective study

BACKGROUND

Preterm birth is a leading cause of infant morbidity and mortality worldwide. The burden of prematurity underscores the need for effective risk reduction strategies. The purpose of this study is to evaluate the efficacy of progesterone therapy, both intramuscular 17-α-hydroxyprogesterone caproate (IM 17-OHPC) and vaginal progesterone, in the prevention of recurrent spontaneous preterm birth (sPTB). The co-primary outcomes included: recurrent spontaneous PTB < 37 and < 34 weeks' gestation.

METHODS

This retrospective cohort study included 637 pregnant patients that delivered at any of the three hospitals within the Los Angeles County healthcare system between October 2015 and June 2021. We compared frequencies of measured variables between each of the progesterone treated groups to no treatment using Pearson chi-squared tests and independent t-tests for categorical and continuous variables, respectively. We estimated crude and adjusted associations between each specific treatment (versus no treatment) and primary outcomes using logistic regression.

RESULTS

Recurrent sPTB < 37 weeks' gestation occurred in 22.3% (n = 64) of those in the no treatment group, 29.1% (n = 86, p = .077) in the 17-OHPC group, and 14.3% (n = 6, p = 0.325) in the vaginal progesterone group. Recurrent sPTB < 34 weeks' gestation was 6.6% (n = 19) in the no treatment group, 11.8% (n = 35, p = .043) in the 17-OHPC group, and 7.1% (n = 3, p = 1) in the vaginal progesterone group. Among all participants, neither 17-OHPC nor vaginal progesterone was significantly associated with a reduction in recurrent sPTB at any time point. Among those with a short cervix, IM 17-OHPC was positively associated with recurrent sPTB < 37 weeks' gestation (aOR 5.61; 95% CI 1.16, 42.9).

CONCLUSIONS

Progesterone therapy of any type did not reduce the risk of recurrent sPTB < 34 or < 37 weeks' gestation compared to no progesterone therapy.

Equivalence of single and standard doses of antenatal corticosteroids for late preterm neonatal outcomes: insights from a secondary analysis

BACKGROUND

The recent paradigm shift of treating individuals at risk of late preterm birth with antenatal corticosteroids warrants an assessment of the effect of single dosage.

OBJECTIVE

To compare outcomes of neonates born in the late preterm period (34.0-36.6 weeks) after a single dose of antenatal corticosteroids vs placebo.

STUDY DESIGN

We performed a secondary analysis of the Antenatal Late Preterm Steroids trial. All individuals enrolled in the parent trial who received only a single dose of either antenatal corticosteroids or placebo and delivered within 24 hours were included. Primary outcome was a composite of respiratory support at 72 hours, including continuous positive airway pressure or high-flow nasal cannula ≥2 hours, oxygen with an inspired fraction of ≥30% for ≥4 hours, or mechanical ventilation.

RESULTS

Of the 2831 individuals in the parent trial, 1083 (38.3%) met inclusion criteria; of them, 539 (49.8%) received a single dose of antenatal corticosteroids and 544 (50.2%) a single placebo dose. The placebo and antenatal corticosteroids groups had similar demographic and clinical characteristics. There was no difference in the rate of the primary respiratory outcome (adjusted risk ratio, 1.12; 95% confidence interval, 0.85-1.47) or in the rate of respiratory distress syndrome (adjusted risk ratio, 1.47; 95% confidence interval, 0.95-2.26) between those who received a single antenatal corticosteroids dose and placebo. An exploratory stratification by randomization-to-delivery intervals of 12-hour increments also showed no association with lower primary respiratory outcome rates.

CONCLUSION

In individuals with late preterm birth pregnancies who received antenatal corticosteroids and delivered before a second dose, there were no differences in neonatal respiratory morbidities compared with placebo. However, this study is not powered to detect treatment efficacy.

Prenatal Vaccination Patterns among Birthing Individuals with History of Preterm Birth in the Pre- and Post-COVID Era

OBJECTIVE

This study aims to explore vaccination acceptance among individuals with a history of preterm birth between March and June during the pre-COVID (2019), early-COVID (2020), and late-COVID (2021) periods.

STUDY DESIGN

This is a cross-sectional, retrospective cohort study of pregnant individuals with a history of preterm birth (<37 weeks' gestation) who initiated care of a subsequent pregnancy during pre-COVID (March-June 2019), early-COVID (March-June 2020), or late-COVID (March-June 2021). The primary outcome of interest was vaccination status for influenza, Tdap, and COVID-19 vaccines. Fisher's exact and chi-square tests were used to investigate association between vaccination status and time periods, race/ethnicity, and insurance.

RESULTS

Among 293 pregnancies, influenza vaccination rate was highest in early-COVID (p < 0.05). There was no statistically significant difference in Tdap or COVID-19 vaccination between time periods. COVID-19 vaccination was highest in individuals with private insurance (p < 0.05). There was no statistically significant difference in vaccination status by race/ethnicity.

CONCLUSION

In this study on high-risk pregnant individuals, the majority of our cohort remained unvaccinated against COVID-19 into the late-COVID period. Additionally, their influenza vaccination rates were greater than the national average in early-COVID and substantially lower than the national average in late-COVID. This shift in influenza vaccination acceptance may have been sparked by COVID-19 vaccine distribution beginning in January 2021 leading to overall vaccination hesitancy. Standardized guidelines and counseling concerning prenatal safety in recommended immunizations may serve as important tools of reassurance and health promotion.

KEY POINTS

· Maternal infections during pregnancy are a risk factor for preterm birth.. · High-risk cohort had low influenza vaccination post-COVID possibly due to COVID-19 vaccine hesitancy.. · Vaccination education may be a uniquely important tool among high-risk pregnant patients..

Ambient temperature and preterm birth: A case-crossover study

OBJECTIVE

To investigate the association between ambient temperature and preterm birth (PTB) and to estimate the population attributable fraction (PAF) of PTBs due to low and high temperatures.

DESIGN

Time-stratified case-crossover design.

SETTING

Japan (46 prefectures, excluding Okinawa), 2011-2020.

SAMPLE

214 050 PTBs registered in the Japan Perinatal Registry Network database among 1 908 168 singleton live births.

METHODS

A quasi-Poisson regression model with a distributed lag nonlinear model was employed to assess the associations between daily mean temperature and PTBs for a lag of 0-27 days in each prefecture. A random effects meta-analysis was conducted by combining effect estimates from the 46 prefectures to estimate pooled relative risks (RRs). The PAFs of the PTBs due to below or above the mean of the 46 median temperatures (16.0°C) were calculated.

MAIN OUTCOME MEASURES

Preterm singleton live births.

RESULTS

The association between daily mean temperature and PTB risk exhibited a U-shaped curve. The adjusted RRs were 1.15 (95% confidence interval [CI] 1.05-1.25) at the mean of the 1st percentiles (0.8°C) and 1.08 (95% CI 1.00-1.17) at the mean of the 99th percentiles (30.2°C) of 46 prefectures, with 16.0°C as the reference temperature. Approximately 2.3% (95% CI 0.6-4.0) of PTBs were attributable to low temperatures.

CONCLUSIONS

Both low and possibly high temperatures were associated with an increased risk of PTBs. These findings may help to inform preventive measures for pregnant women.

Effect of low-molecular-weight heparin on placenta-mediated fetal growth restriction in a tertiary referral hospital: A 7-year retrospective cohort study

OBJECTIVE

To investigate the effect of low-molecular-weight heparin (LMWH) on placenta-mediated fetal growth restriction (FGR).

METHODS

A cohort of 570 pregnant women diagnosed with placenta-mediated FGR were enrolled from January 1, 2015 through to December 31, 2021. A birth database, including demographic data, antenatal complications, and detailed delivery and newborn data, was created to collect variables from the Hospital Information System (HIS) Database. The unique personal registration number, assigned to each patient on first registration with HIS in the West China Second University Hospital, was used to link these patients. LMWH use was defined as at least 1-week prescription from diagnosis of placenta-mediated FGR. Pregnant women received LMWH (Enoxaparin 4000 IU/day) by self-administered subcutaneous injection only when they agreed and signed informed consent. Primary outcome was intrauterine fetal death after 20 weeks of pregnancy. Secondary outcomes included preterm birth (PB), Apgar score less than 7 at 1 min, admission to neonatal intensive care unit (NICU), and birth weight. Logistic regression analysis was conducted to compute adjusted odds ratio (aOR) with 95% confidence intervals (CI) for outcomes.

RESULTS

After controlling for confounders, LMWH use was associated with a decreased risk of intrauterine fetal death (aOR 2.49, 95% CI 1.35-4.57, P = 0.003), PB before 37 weeks of pregnancy (aOR 3.35, 95% CI 2.14-5.23, P < 0.001), PB before 34 weeks of pregnancy (aOR 2.25, 95% CI 1.36-3.74, P = 0.002), Apgar score less than 7 at 1 min (aOR 2.25, 95% CI 1.36-3.74, P = 0.002), NICU admission (aOR 2.29, 95% CI 1.48-3.55, P < 0.001). Using LMWH increased the mean birth weight in PB before 32 weeks of pregnancy (mean ± standard deviation [SD] 1126.4 ± 520.0 g, P = 0.020), PB before 37 weeks of pregnancy (mean ± SD 1563.9 ± 502.7 g, P = 0.019), early-onset FGR (mean ± SD 2125.2 ± 665.7 g, P < 0.001), late-onset FGR (mean ± SD 2343.4 ± 507.9, P < 0.001), and non-severe FGR (mean ± SD 2231.1 ± 607.2 g, P < 0.001).

CONCLUSION

Use of LMWH can significantly improve the fetal and neonatal outcomes among pregnant women with placenta-mediated FGR, particularly reducing the risk of intrauterine fetal death.

Perinatal outcomes following abdominoplasty: a retrospective study and review of current literature

BACKGROUND

Abdominoplasty surgery is a common body contouring surgery to remove excess fat and skin and restore weakened or separated abdominal muscles caused by aging, pregnancy, or weight fluctuations. There is limited literature regarding patient and pregnancy outcomes after abdominoplasty.

OBJECTIVE

This study aimed to determine whether there was a correlation between adverse pregnancy outcomes and history of abdominoplasty.

STUDY DESIGN

Our study used a large federated deidentified national health research network with data sourced from 68 healthcare organizations within the United States (TriNetX; data accessed on August 19, 2022). All patients with a record of pregnancy were identified using the International Classification of Diseases, Ninth Revision and Tenth Revision, codes and were grouped into those with a history of abdominoplasty and those without. This study evaluated the perinatal outcomes of fetal growth restriction, abnormal umbilical artery Dopplers, gestational hypertension, preeclampsia, preterm delivery, preterm premature rupture of membranes, gestational diabetes mellitus, macrosomia, stillbirth, abnormal placentation, and wound disruption or infection occurring during a patient's pregnancy after abdominoplasty. Propensity matching was performed to account for potential confounders. An alpha level of <.05 was considered statistically significant.

RESULTS

Of the 44,737 patients meeting our criteria, 304 had a history of abdominoplasty, whereas 44,433 did not (control). Our study found that patients with a history of abdominoplasty had significantly higher gravidity, were largely located in the Southern and Midwest region, and had higher counts of vaginal deliveries and cesarean deliveries than the control cohort (Table 1). After propensity score matching, our study found a lower risk of preeclampsia and preterm premature rupture of membranes in patients with abdominoplasty (odds ratio, 0.46; 95% confidence interval, 0.32-0.67; P<.0001) (Table 2). Furthermore, abdominoplasty was associated with an increased risk of preterm delivery (odds ratio, 2.15; 95% confidence interval, 1.48-3.13; P=.0002) (Table 2). Lastly, this study did not find significant differences in the other perinatal outcomes (Table 2).

CONCLUSION

Our data suggest that abdominoplasty may be associated with a relative increase in the rates of preterm delivery and cesarean delivery and that other perinatal outcomes are not increased. This provides evidence that future desire for pregnancy need not be a relative contraindication to abdominoplasty.

Pregnancy outcomes in the medical management of glaucoma: An international multicenter descriptive survey

PURPOSE

To determine if glaucoma medications are associated with pregnancy and/or postnatal complications.

METHODS

Multicenter descriptive survey. Subjects were female patients 18-45 years who were previously pregnant with a diagnosis of glaucoma or ocular hypertension prior to pregnancy. Chart review queried diagnosis, glaucoma severity, and race. Survey questions were asked for each pregnancy and queried pregnancy age, medications used, and pregnancy outcomes/complications.

RESULTS

114 pregnancies of 56 patients (mean 2.0 pregnancies per patient) were included. Three pregnancies with therapeutic abortion were excluded from further analysis. Mean age during pregnancy was 29.1 ± 5.7 years. Of the 111 pregnancies, 20 (18.0%) used no medications and 91 (82.0%) used at least one medication. Medications were topical carbonic anhydrase inhibitors (n = 45), beta-blockers (n = 55), alpha-agonists (n = 56), and prostaglandin analogues (n = 28). Outcomes were: preterm contractions/labour (6.3%), miscarriage (4.5%), stillbirth (4.5%), induction of labour (11.9%), emergency/unplanned caesarean delivery (13.9%), neonatal intensive care unit (NICU) stay (15.8%), congenital anomalies (8.1%), and low birth weight (10.9%). Fisher exact test assessed outcome associations with individual agents, use of any agent, and different number of agents. Alpha-agonist use was associated with NICU stay: 25.5% rate (p = 0.012) in alpha-agonist use. Most of the alpha-agonist use NICU stays occurred in pregnancies with third trimester use. All other associations were not statistically significant.

CONCLUSIONS

The data from this survey suggest an overall favourable safety profile for topical glaucoma medications in pregnancy, but further investigation is needed. Caution should be employed regarding third trimester alpha-agonist use owing to association with NICU stay.