Risk factors for spontaneous preterm delivery

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.

Traditional female cervical cauterization and risk of preterm birth in Somalia: a single-center prospective observational study

Numerous traditional practices are both beneficial and harmful. Traditional harmful practices, such as female genital mutilation and traditional cervical cauterization, are carried out for a number of reasons but can have negative health and social effects. In addition to deeply held beliefs, a lack of knowledge and awareness of the consequences of these practices contributes to the persistence of these issues. The objective of this study is to examine whether traditional cervical cauterizations were associated with preterm births in Somalia. This prospective cohort study was conducted at our hospital over a one-year period. Seven hundred and two patients were included in this study; these patients were divided into two groups, cauterized and non-cauterized groups, and the two groups were compared on pregnancy outcomes. We examined whether traditional cervical cauterizations were associated with adverse pregnancy outcomes, including preterm births. According to the findings of this study, traditional cervical cauterization was prevalent among patients visiting MSTREH (n = 328, 46.7%). Infections of the uterine cervix and infertility were the two main indications for cauterization, 44.8%, and 34.8%, respectively.Being older, uneducated, and poverty were significantly associated with traditional cauterization (P < 0.001). There was a significant correlation between prior traditional cervical cauterization and the risk of preterm births. Women with prior cauterization were two and half times more likely to deliver a preterm fetus (OR: 2.64, 95% CI 2.15-3.33) compared to non-cauterized mothers. Our findings show that women who have previously undergone traditional cervical cauterization have a significantly higher risk of preterm birth and negative pregnancy outcomes than non-cauterized women. Health professionals, particularly those who are close to the community, are crucial in developing and putting into practice plans to end harmful traditions in Somalia.

Risk and Protective Factors for Preterm Birth Among Racial, Ethnic, and Socioeconomic Groups in California

Importance

Preterm birth (PTB) (gestational age <37 weeks) is a major cause of infant mortality and morbidity in the US and is marked by racial and ethnic and socioeconomic inequities. Further research is needed to elucidate the association of risk and protective factors with trends in PTB rates and with related inequities.

Objective

To describe the association of PTB rates with inequities as well as related risk and protective factors over the past decade in a US population-based cohort.

Design, Setting, and Participants

This retrospective cohort study of singleton live births in California from January 1, 2011, to December 31, 2022, was conducted using vital statistics records and hospital records. The cohort included births with a gestational age of 22 to 44 weeks.

Main Outcomes and Measures

Preterm birth rates by racial and ethnic group and by public and nonpublic insurance (considered as a proxy for socioeconomic status) were studied across years. Log-linear regression (relative risks with 95% CIs) was used to evaluate risk and protective factors within groups. Associations of PTB rates with risk and protective factors were assessed.

Results

This study included 5 431 018 singleton live births to individuals who identified as American Indian or Alaska Native (0.3%), Asian (14.2%), Black (4.9%), Hispanic (47.8%), or White (27.0%). A total of 43.1% of births were to individuals with public health insurance. From 2011 to 2022, the overall PTB rate increased from 6.8% to 7.5% (change [SE], 10.6% [0.6%]; z score of 18.5; P < .001). Differences in PTB rates and associated changes were observed for racial and ethnic groups and insurance groups. For example, 2022 PTB rates ranged from 5.8% among White individuals with nonpublic insurance to 11.3% among Black individuals with public health insurance. From 2011 to 2022, PTB rates decreased from 9.1% to 8.8% (change [SE], -3.5% [4.2]; z score of -0.8; P = .42) among Black individuals with nonpublic insurance, whereas they increased from 6.4% to 9.5% (change [SE], 49.8% [16.0%]; z score of 3.1; P = .002) among American Indian or Alaska Native individuals with nonpublic insurance. Increases in some risk factors (eg, preexisting diabetes, sexually transmitted infections, mental health conditions) were observed in most groups, and decreases in some protective factors (eg, participation in the California Women, Infants, and Children program) (P for trend < .001 from 2011 to 2021) were observed mostly in low-income groups.

Conclusions and Relevance

In this cohort study of singleton live births in California, PTB rates increased in many groups. Persistent racial and ethnic and socioeconomic inequities were also observed. Changes in risk and protective factors provided clues to patterns of PTB. These data point to an urgent need to address factors associated with PTB at both the individual and population levels.

Indirect Effects of Neighbourhood Socioeconomic Status on Preterm Birth Risk in an Argentine Population

BACKGROUND

Preterm birth (PTB) is the main condition related to perinatal morbimortality worldwide. The aim of this study was to determine the indirect effects of neighbourhood socioeconomic status (NSES) on the risk of spontaneous PTB.

METHODS

We carried out a retrospective case-control study including sociodemographic and obstetric data of multigravid women who gave birth at a maternity hospital in Tucumán, Argentina, between 2005 and 2010: 949 women without previous PTB nor pregnancy loss who delivered at term and 552 who had spontaneous PTB. NSES was estimated from the Unsatisfied Basic Needs index of census data. Variables selected through penalised regressions were used to create a data-driven Bayesian network; then, pathways were identified and mediation analyses performed.

RESULTS

Maternal age less than 20 years mediated part of the protective effect of high NSES on spontaneous PTB [natural indirect effect (NIE) -0.0125, 95% confidence interval (CI) (-0.0208, -0.0041)] and on few prenatal visits (< 5) [NIE - 0.0095, 95% CI (-0.0166, -0.0025)]. These pathways showed greater sensitivity to unobserved confounders that affect the variables mediator-outcome in the same direction, and exposure-mediator in the opposite direction. They did not show sensitivity to observed potential confounders, nor to the parameterization used to define NSES. Meanwhile, urinary tract infections showed a trend in mediating the effect of low NSES on spontaneous PTB [NIE 0.0044, 95% CI (-0.0006, 0.0093), P 0.0834].

CONCLUSIONS

High NSES has protective indirect effects on spontaneous PTB risk, mainly associated with a lower frequency of teenage pregnancy.

An updated study of the relationship between bacterial infections and women's immune system, focusing on bacterial compositions with successful pregnancy

Genital tract infections can cause a variety of harmful health outcomes, including endometritis, bacterial vaginosis, and pelvic inflammatory disease, in addition to infertility. Anaerobic bacteria, such as Gardnerella vaginalis, Megasphaera spp., and Atopobium vaginae, are more commonly identified in cases of bacterial vaginosis than lactobacilli. It is unknown how the microorganisms that cause pelvic inflammatory diseases and endometritis enter the uterus. Both prospective and retrospective research have connected pelvic inflammatory disorders, chronic endometritis, and bacterial vaginosis to infertility. Similar to bacterial vaginosis, endometritis-related infertility is probably caused by a variety of factors, such as inflammation, immune system recognition of sperm antigens, bacterial toxins, and a higher risk of STDs. Preconception care for symptomatic women may include diagnosing and treating pelvic inflammatory disease, chronic endometritis, and bacterial vaginosis before conception to optimize the results of both natural and assisted reproduction.

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.

The association between maternal prenatal hair cortisol concentration and preterm birth: A systematic review and meta-analysis

BACKGROUND

The risk of preterm birth (PTB) increases when experiencing stress during pregnancy. Chronic stress has been associated with a dysregulation of the hypothalamic-pituitary-adrenal axis, for which hair cortisol concentration (HCC) is a promising biomarker. However, previous studies on the association between HCC and PTB yielded inconsistent results. This systematic review and meta-analysis synthesized previous studies on the association between maternal HCC before and during pregnancy and spontaneous PTB.

METHODS

Data was extracted from N = 11 studies with k = 19 effect sizes retrieved from PubMed, Embase, Web of Science, CINAHL and citation searching by hand in June 2023 and updated in October 2023. Standardized mean differences were calculated, and a random-effects three-level meta-analysis was conducted. Effect heterogeneity was assessed using Q and I2.

RESULTS

HCC during pregnancy was higher among PTB than term groups, but effects were not statistically significant (z = 0.11, 95% CI: - 0.28, 0.51, p = .54) and total heterogeneity was high (Q16 = 60.01, p < .001, I2Total = 92.30%). After leaving out two possible outlier studies in sensitivity analyses, HCC was lower among preterm compared to term delivering groups, although not statistically significant (z = - 0.06, 95% CI: - 0.20, 0.08, p = .39) but with a substantially reduced total heterogeneity (Q12 = 16.45, p = .17, I2Total = 42.15%). No moderators affected the estimates significantly, but an effect of trimester and gestational age at delivery is likely.

CONCLUSION

There is currently no evidence of prenatal HCC differences between PTB and term groups as effects were small, imprecise, and not significant. Low statistical power and methodological weaknesses of the small-scale studies challenge possible biological inferences from the small effects, but further research on HCC during pregnancy is highly encouraged.

Delivery Mode and Neurological Complications in Very Low Birth Weight Infants

OBJECTIVE

The risk of intraventricular hemorrhage (IVH) and periventricular leukomalacia is associated with low birth weight and gestational age. Caesarean section (CS) may reduce the risk of IVH, although it has been a matter of debate. The aim of this study was to evaluate the influence of the mode of delivery (MOD) on the development of IVH and cystic periventricular leukomalacia (cPVL).

STUDY DESIGN

We analyzed an initial cohort of 11,023 very low birth weight (VLBW) infants born between January 2010 and December 2019. Infants with major malformations and gestational age <23 weeks and ≥32 weeks were excluded. A final cohort of 8,251 newborns was analyzed. Data was collected from Portuguese National very low birth weight registry. Cases were classified as vaginal delivery (VD) or CS. Outcome was assessed in univariate and logistic regression analyses.

RESULTS

The median gestational age was 29 weeks (IQR 3.3) and the median weight was 1,100 g (IQR 555). The prevalence of IVH was significantly higher in the VD group versus the CS group, across all grading levels:1,144 newborns had grade I IVH (16% VD vs. 14% CS, p <0.01), 706 had grade II IVH (12% VD vs. 7.6% CS, p <0.01), and 777 had grade III IVH (14% VD vs. 7.9% CS, p <0.01). Post-hemorrhagic ventricular dilatation occurred in 457 newborns (8.3% VD vs. 4.6% CS, p <0.01) and 456 newborns had periventricular hemorrhagic infarction (8.4% VD vs. 4.5% CS, p <0.01). There was no association between MOD and cPVL. After applying a logistic regression analysis, including known risk factors for IVH and cPVL, VD was independently associated with an increased risk of IVH (odds ratio [OR] 1.600[1.423-1.799], p <0.001) and its complications (OR 1.440[1.195-1.735], p <0.001). MOD was not associated with an increased risk of cPVL.

CONCLUSION

Our study suggests that CS is associated with a reduced risk of IVH and its complications in preterm VLBW infants < 32 weeks of gestational age. A CS should be considered in this group of infants to prevent the development of IVH and its complications.

KEY POINTS

· IVH and cPVL are risk factors for neurological disabilities.. · CS may decrease the risk of IVH in preterms <32 weeks GA.. · There is no association between the MOD and cPVL..

Impacts of heat and wildfire on preterm birth

BACKGROUND

Climate change continues to increase the frequency, intensity, and duration of heat events and wildfires, both of which are associated with adverse pregnancy outcomes. Few studies simultaneously evaluated exposures to these increasingly common exposures.

OBJECTIVES

We investigated the relationship between exposure to heat and wildfire smoke and preterm birth (PTB).

METHODS

In this time-stratified case-crossover study, participants consisted of 85,806 California singleton PTBs (20-36 gestational weeks) from May through October of 2015-2019. Birthing parent ZIP codes were linked to high-resolution daily weather, PM2.5 from wildfire smoke, and ambient air pollution data. Heat day was defined as a day with apparent temperature >98th percentile within each ZIP code and heat wave was defined as ≥2 consecutive heat days. Wildfire-smoke day was defined as a day with any exposure to wildfire-smoke PM2.5. Conditional logistic regression was used to calculate the odds ratio (OR) and 95% confidence intervals (CI) comparing exposures during a hazard period (lags 0-6) compared to control periods. Analyses were adjusted for relative humidity, fine particles, and ozone.

RESULTS

Wildfire-smoke days were associated with 3.0% increased odds of PTB (ORlag0: 1.03, CI: 1.00-1.05). Compared with white participants, associations appeared stronger among Black, Hispanic, Asian, and American Indians/Alaskan Native participants. Heatwave days (ORlag2: 1.07, CI: 1.02-1.13) were positively associated with PTB, with stronger associations among those simultaneously exposed to wildfire smoke days (ORlag2: 1.19, CI: 1.11-1.27). Similar findings were observed for heat days and when other temperature metrics (e.g., maximum, minimum) were used.

DISCUSSION

Heat and wildfire increased PTB risk with evidence of synergism. As the occurrence and co-occurrence of these events increase, exposure reduction among pregnant people is critical, especially among racial/ethnic minorities.

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.

The role of bacterial genital infections in spontaneous preterm delivery: a case-control study

Background

Spontaneous preterm delivery is defined as the beginning of the birth process before the 37th week of pregnancy. The presence of microorganisms in the fetal membranes is accompanied by an increase in the production of prostaglandin, one of the important factors associated with the prevalence of preterm birth. The invasion of microorganisms leads to the production of protease, coagulase, and elastase, which directly stimulate the onset of childbirth. We investigated the role of genital infections in women with preterm birth.

Methods

The present case-control study was conducted in the west of Iran on 100 women with spontaneous preterm delivery (following 24 weeks of gestation and before 36 weeks and 6 days) as the case group and 100 women with normal delivery as controls. A questionnaire was applied to collect the data. Polymerase chain reaction and pathological examination of the placenta were performed.

Results

The average age in women with normal delivery (30.92 ± 5.10) in women with spontaneous preterm delivery (30.27 ± 4.93). The prevalence of Chlamydia trachomatis, Neisseria gonorrhea, Listeria monocytogenes, and Mycoplasma genitalium infections was zero in both groups. The highest prevalence of Gardnerella vaginalis was 19 (19%) in the case group and Ureaplasma parvum 15 (15%) in the control group. Also, Placental inflammation was zero in controls and 7(7%) in the patient group. There was a significant relationship between Gardnerella vaginalis bacteria and spontaneous preterm delivery.

Conclusion

The results of our study showed that except for Gardnerella vaginalis bacteria, there is no significant relationship between the above bacterial infections and spontaneous preterm birth. Moreover, despite the significant reduction in the prevalence of many sexually transmitted infections in this research, it is still suggested to increase the awareness of people, including pregnant women, about the ways it can be transmitted by gynecologists and health and treatment centers.

Risk factors of early spontaneous preterm birth despite carrying a cervical pessary in singleton pregnancies with a short cervix: Development of a risk prediction model

Introduction

We aimed to identify the incidence and risk factors of spontaneous preterm birth in pessary carriers with singleton pregnancies and a short cervix in the mid-trimester of pregnancy.

Material and Methods

Patient data were obtained from the PECEP Trial. We analyzed singleton pregnancies in pessary carriers with a short cervix (≤25 mm) between 18 and 22 gestational weeks. Demographics and obstetric history were compared to identify risk factors for spontaneous preterm birth < 34 gestational weeks. Each demographic and obstetric variable was compared between spontaneous preterm birth < 34 and ≥ 34 weeks of gestation.Regression analysis was used to identify risk factors. A risk score model was generated using the odds ratio for significant factors. The risk score model and spontaneous preterm birth risk were assessed using the receiver operating characteristic curve. Perinatal outcomes were compared by risk score.

Results

Among 190 pregnant individuals, 12 (6.3%) had spontaneous preterm birth < 34 gestational weeks. In the bivariate analysis, statistically significant differences between those with and without spontaneous preterm birth were only observed for mean cervical length at diagnosis and mean cervical length after pessary placement. By multiple logistic regression analysis, maternal age (OR 0.818; 95% CI 0.69-0.97; P 0.020), cervical length at diagnosis (OR 0.560; 95% CI 0.43-0.73; P < 0.001) and smoking status (OR 7.276; 95% CI 1.02-51.80; P 0.048) remained significantly associated with spontaneous preterm birth.The ROC curve from the multiple logistic regression analysis, including cervical length, maternal age and smoking status, had an area under the curve (AUC) of 0.952 (P < 0.001). The ROC curve for the risk score model incorporating all three variables had an AUC of 0.864 (95% CI 0.77-0.96; P < 0.001). A high-risk score was predictive of spontaneous preterm birth with a sensitivity of 75%, specificity of 84%, positive predictive value of 24%, and negative predictive value of 98%.Women with a high-risk score had a significantly reduced latency to delivery and poorer neonatal outcomes than those with a low-risk score.

Conclusions

Patients at a high risk for spontaneous preterm birth despite pessary therapy may be identified using cervical length at diagnosis added to maternal age and smoking status.

Preterm delivery and maternal obesity remain common complications in pregnancies with type 1 diabetes-A nationwide study in Sweden

AIM

A primary goal of obstetric care of women with type 1 diabetes (T1D) is to reduce the risks of preterm birth (PTB). Besides hyperglycaemia, maternal obesity is an important risk factor for PTB in T1D. However, it's unclear if public health efforts decreased risks of maternal obesity and PTB in pregnancies with T1D. We examined time-trends over the last 20 years in the distribution of gestational ages at birth (GA) in offspring of women with T1D in Sweden, and in maternal BMI in the same mothers.

METHODS

Population-based cohort study, using data from national registries in Sweden. To capture differences not only in the median values, we used quantile regression models to compare the whole distributions of GA's and early pregnancy BMI between deliveries in 1998-2007 (P1) and 2008-2016 (P2). Multivariable models were adjusted for differences in maternal age, smoking and education between periods 1 and 2.

RESULTS

The study included 7639 offspring of women with T1D between 1998 and 2016. The 10% percentile GA, increased with 0.09 days (95% CI: -0.11 to 0.35) between P1 and P2. The 90% percentile for BMI was 1.20 kg/m2 higher (95% CI: 0.57 to 1.83) in P2. Risks of PTB remained stable over time also when adjusting for maternal BMI.

CONCLUSION

Despite modern diabetes management, the distribution of GA, and consequently the risk of PTB in T1D, remained unchanged from 1998 to 2016. During the same time, maternal BMI increased, particularly in the already obese.

Cervical length screening among low-risk women; relationship of body mass index on cervical length and risk of preterm birth

BACKGROUND

Preterm birth (PTB) contributes to nearly 11% of all deliveries in the world. The majority of spontaneous preterm birth (sPTB) remains unexplained. Risk factors include abnormal body mass index (BMI), short cervical length, comorbidities and many more. However, there is limited study on the association between body mass index, cervical length and preterm birth in Malaysia among low-risk women. Hence, we aim to examine the relationship between body mass index, cervical length and the risk of spontaneous preterm birth.

METHOD

In this prospective cohort study, pregnant women between 16 and 24 weeks who fulfilled the criteria were recruited. Women with history of preterm birth were excluded. Demographic and clinical data (age, BMI, ethnicity, education level and parity) were obtained. Cervical length was measured using transvaginal scan. Patients were then followed up till delivery to determine their delivery gestation and outcome of delivery.

RESULTS

Out of 153 women who participated in this study, 146 women had cervical length of more than 30 mm, six had cervical length between 25 mm and 30 mm and one had cervical length of 24 mm. There were nine (9) cases of sPTB, with all of them being late preterm with normal midtrimester cervical length. Almost half of them (44%) were overweight/obese. A significant association was found between age, cervical length, and parity compared to BMI. Nevertheless, no significant association was seen between the BMI and risk of sPTB.

CONCLUSION

This study demonstrates a higher BMI is associated with longer cervical length, but it is not necessarily protective against sPTB. Hence, we concluded there is a limited role in cervical length screening among low-risk women regardless of their BMI in predicting sPTB.

Utility of cervical pessary in the prevention of preterm birth in triplet pregnancies: A single-center observational retrospective study of 165 triplet pregnancies

OBJECTIVE

Premature births are a health problem arising in triplet pregnancies, resulting in high levels of morbidity and mortality. The objective of this study is to evaluate the utility of cervical pessaries in reducing prematurity (<34 weeks) in triplet pregnancies.

METHODS

This is a single-center, retrospective case-control study regarding triplet pregnancies with follow-up at the La Paz University Hospital between 2000 and 2023. Maternal characteristics, obstetric and perinatal outcomes, and the use of cervical pessaries were examined.

RESULTS

165 triplet pregnancies were analyzed: 87 (52.7 %) in the case group (premature triplet pregnancies) and 78 in the control group (non-premature triplet pregnancies). A cervical pessary was inserted in 15 (17.2 %) triplet pregnancies in the case group and in 12 (16.7 %) triplet pregnancies in the control group (p = 0.92; OR = 1.04 (0.46-2.35)). A pessary was later inserted in the non-premature group (p = 0.01). The risk of preterm labor and the use of tocolytics ± glucocorticoids were found to be significantly more frequent in the premature group, with p = 0.01; OR = 2.30 (1.21-4.36) and p < 0.01; OR = 2.36 (1.23-4.44), respectively. Protocol-based cesarean sections were more frequent in the non-premature group (p < 0.01), while cesarean sections due to maternal complications (p < 0.01) and premature membrane rupture (p < 0.01) were more frequent in the premature group.

CONCLUSION

The cervical pessary is not useful in preventing preterm births (< 34 weeks) in triplet pregnancies. It is likely that being pregnant with triplets is a powerful independent factor associated with prematurity, despite other pregnancy conditions. Women who are pregnant with triplets and at risk of preterm labor and those taking tocolytics ± glucocorticoids may benefit from pessary insertion.

Molybdenum Concentration and the Risk of Spontaneous Preterm Birth: A Nested Case-Control Study - Beijing Municipality, China, 2018-2020

What is already known about this topic?

The level of molybdenum (Mo) in a mother's urine has been linked to the growth rate of the fetus and the blood pressure levels in children.

What is added by this report?

We evaluated the variations in maternal plasma Mo concentrations throughout pregnancy and their potential association with the risk of spontaneous preterm birth (SPB).

What are the implications for public health practice?

Future research must determine the Mo levels in pregnant women across various regions in China. Moreover, particular attention needs to be given to the potential increase in Mo concentration throughout pregnancy and its possible adverse impacts on the health of both the mother and the fetus.

Risk of Hypertensive Disorders and Preterm Birth in Pregnant Women With Systemic Vasculitides: A Nationwide Population-Based Cohort Study

OBJECTIVE

Even though systemic vasculitides (SVs) affect primarily patients over 50 years of age, they can occur among women of childbearing age. Preterm birth (PTB) and hypertensive disorders are frequent complications of pregnancy in SVs. This study aims to evaluate the risk of hypertensive disorders and PTB among pregnant women with SVs, and to identify associated risk factors.

METHOD

Using the French health insurance data warehouse, we conducted a nationwide cohort study including all pregnancies between 2013 and 2018 in women with SVs. Theses pregnancies were matched to pregnancies among women without SVs. We estimated risk of hypertensive disorders and PTB risk during pregnancy among women with SVs and investigated associated risk factors using a nested case-control design.

RESULTS

Among 3,155,723 pregnancies, we identified 646 pregnancies in women with SVs, matched to 3,230 controls. SVs were significantly associated with hypertensive disorders (odds ratio [OR] 1.7, 95% confidence interval [95% CI] 1.3-2.2) and PTB (OR 1.8, 95% CI 1.4-2.3). Chronic renal failure before pregnancy, history of or treated arterial hypertension, the occurrence of vasculitides flare during pregnancy, and the subgroup of SVs were independently associated with the occurrence of hypertensive disorders. Maternal age at delivery, chronic renal failure before conception, and the occurrence of vasculitides flare during pregnancy were independently associated with the occurrence of PTB.

CONCLUSION

About one of seven pregnancies in women with SVs is associated with hypertensive disorders or preterm birth. The occurrence of vasculitides flare was associated with these complications. Our findings support the importance of prepregnancy counseling to ensure disease stability.

Strategies for Safeguarding High-Risk Pregnancies From Preterm Birth: A Narrative Review

Preterm birth is the delivery of a live fetus before the 37th week of gestation. Preterm birth may stem from various factors, including premature rupture of membranes, spontaneous preterm labor, or medically induced circumstances. Premature delivery can result in serious and long-lasting difficulties even for infants who survive, as it is the leading cause of death for infants under five years old. Numerous nations have implemented initiatives to detect and track pregnant women who may give birth before their due date. Numerous therapies are available to protect these at-risk groups from the devastating effects of premature delivery, given the complex nature of preterm birth risk factors. Among the preventive measures, prophylactic progesterone appears to hold significant promise, while cervical cerclage proves effective in cases of cervical insufficiency. Conversely, pessaries show no discernible beneficial effects in reducing the risk of preterm birth. Regular antenatal visits are imperative for frequent patient evaluation and screening for potential risk factors. Adopting a healthy lifestyle can influence the risk of developing preeclampsia, with regular physical activity, a fiber-rich diet, and smoking cessation serving to mitigate the risk of preterm birth. The efficacy of bed rest in preventing preterm birth remains inconclusive due to insufficient evidence. This study aims to explore various preventive strategies for averting premature birth in high-risk women.

Recent Advances and Challenges in the Early Diagnosis and Treatment of Preterm Labor

Preterm birth (PTB) is the primary cause of neonatal mortality and long-term disabilities. The unknown mechanism behind PTB makes diagnosis difficult, yet early detection is necessary for controlling and averting related consequences. The primary focus of this work is to provide an overview of the known risk factors associated with preterm labor and the conventional and advanced procedures for early detection of PTB, including multi-omics and artificial intelligence/machine learning (AI/ML)- based approaches. It also discusses the principles of detecting various proteomic biomarkers based on lateral flow immunoassay and microfluidic chips, along with the commercially available point-of-care testing (POCT) devices and associated challenges. After briefing the therapeutic and preventive measures of PTB, this review summarizes with an outlook.

Impact of corticosteroid exposure on preterm labor in neonates eventually born at term

OBJECTIVE

To evaluate the impact of antenatal corticosteroid therapy (ACS) on birth outcomes in term infants exposed during pregnancy.

STUDY DESIGN

Exposed newborns were compared with non-exposed controls in a 1 to 2 design. Multivariate analysis was used to assess the effect of ACS exposure on neonatal outcomes.

RESULT

408 newborns were included (136 exposed to ACS, 272 non-exposed). Mean ± SD head circumference (HC) was 33.7 ± 1.4 vs 34.3 ± 1.6 cm, p = 0.001 in exposed vs controls; birth weight was 3.1 ± 0.4 vs 3.3 ± 0.4 kg, p = 0.0001; and birth height was 47.9 ± 2.1 vs. 49.1 ± 2.0 cm, p < 0.0001. Hypocalcemia (4.4 vs 0.7%, p = 0.019) and feeding difficulties (5.1 vs 1.5%, p = 0.047) were significantly more common in exposed newborns. Multivariate analysis for HC showed a significant independent association with ACS exposure (β = -0.5, p = 0.009).

CONCLUSION

Term newborns exposed to ACS have lower birth HC and higher risk of neonatal complications.

CLINICAL TRIAL REGISTRATION

NCT05640596.

Gene-environment interactions and preterm birth predictors: A Bayesian network approach

Preterm birth (PTB) is the main condition related to perinatal morbimortality worldwide. The aim of this study was to identify gene-environment interactions associated with spontaneous PTB or its predictors. We carried out a retrospective case-control study including parental sociodemographic and obstetric data as well as newborn genetic variants of 69 preterm and 61 at term newborns born at a maternity hospital from Tucumán, Argentina, between 2005 and 2010. A data-driven Bayesian network including the main PTB predictors was created where we identified gene-environment interactions. We used logistic regressions to calculate the odds ratios and confidence intervals of the interactions. From the main PTB predictors (nine exposures and six genetic variants) we identified an interaction between low neighbourhood socioeconomic status and rs2074351 (PON1, genotype GG) variant that was associated with an increased risk of toxoplasmosis (odds ratio 12.51, confidence interval 95%: 1.71 - 91.36). The results of this exploratory study suggest that structural social disparities could influence the PTB risk by increasing the frequency of exposures that potentiate the risk associated with individual characteristics such as genetic traits. Future studies with larger sample sizes are necessary to confirm these findings.

Is Parity a Risk Factor for Late Preterm Birth? Results from a Large Cohort Study

Most preterm births occur in the late preterm period. While prematurity-related adverse outcomes are significantly diminished when birth occurs during this period, these infants are still at increased risk of complications. Parity affects the incidence of obstetric complications. The purpose of this study was to determine whether parity impacts the risk of spontaneous late preterm birth (SLPTB) and associated complications. A retrospective observational cohort study was conducted. Patients were divided into three study groups according to parity. The primary outcome was the rate of SLPTB in each group. Secondary outcomes were unplanned cesarean delivery (UCD), prolonged third stage of labor respiratory distress syndrome (RDS), transient tachypnea of the newborn (TTN), intraventricular hemorrhage (IVH), neonatal hypoglycemia, duration of NICU admission, neonatal death, and composite adverse neonatal outcome (CANO). Primiparas were more likely to have SLPTB, UCD, and CANO compared to multiparas (2.6% vs. 1.9% OR 1.5 [1.3-1.7] p < 0.01) (4.1% vs. 1.3% OR 2.7 [1.2, 5.9] p < 0.01) (8.5% vs. 4.2 OR 2.1 [1.3-3.5] p = 0.002) and grandmultiparas (2.6% vs. 1.7% OR 1.4 [1.2-1.5] p < 0.001) 8.5% vs. 4.4% OR 2.0 [1.1, 3.8], p = 0.01) but no difference in UCD compared to grandmultiparas (4.1% vs. 3.3% OR 1.2 [0.6-2.7] p = 0.28). Primiparas are at increased risk of SLPTB and UCD, and this is accompanied by an increased risk of adverse neonatal outcomes.

Workplace Productivity Loss and Indirect Costs Associated With Preterm Birth in the United States

OBJECTIVE

To estimate workplace productivity loss and indirect costs in the year after birth among individuals who deliver preterm in the United States.

METHODS

This retrospective, observational cohort study estimated workplace productivity loss and indirect costs for individuals aged 18-55 years with an inpatient delivery between January 1, 2016, and September 30, 2021, using data from the Merative MarketScan Commercial Claims and Encounters database and the Health and Productivity Management database. Workdays lost and costs attributable to medical-related absenteeism, workplace absenteeism (defined as sick leave, leave, recreational leave, Family Medical Leave Act); disability (defined as short-term and long-term disability), and aggregate workplace productivity loss, a combined outcome measure, were compared between propensity-score-matched birth cohorts: preterm birth (before 37 weeks of gestation) and full-term birth (at or after 37 weeks of gestation). Outcomes were also compared between the full-term birth cohort and preterm birth subgroups (before 32 weeks of gestation and before 34 weeks of gestation). Estimations of indirect costs assumed an 8-hour workday. Costs were inflated to December 2021 U.S. dollars.

RESULTS

In total, 37,522 individuals were eligible for medical-related absenteeism, 1,028 for workplace absenteeism, 7,880 for disability, and 396 for aggregate workplace productivity loss after propensity score matching. Compared with full-term birth, preterm birth was associated with more workdays lost and costs in the year after childbirth attributable to medical-related absenteeism (differences of 4.2 days and $1,045, P <.001) and disability (differences of 2.8 days and $422, P <.001). Preterm birth was not associated with workplace absenteeism (differences of 1.4 days and $347, P =.787) and aggregate workplace productivity loss (differences of 5.2 days [ P =.080] and $1,021 [ P =.093]). Numerical differences were greater in magnitude and inversely related to gestational age at birth across outcomes.

CONCLUSION

Preterm birth was associated with medical-related absenteeism, disability claims, and indirect costs in the year after birth compared with full-term birth.

Pregnant Populations which Benefit from Vaginal Progesterone for Preventing Preterm Birth at <34 Weeks and Neonatal Morbidities: A Systematic Review and Meta-analysis

This study aimed to assess vaginal progesterone's effect on different populations and performed comparation between women with varied risk factors. Embase, PubMed, Cochrane library (CENTRAL) were searched without restriction to language up to February 25, 2021. Randomized controlled trials (RCTs) assessing vaginal progesterone administered to women at risk of preterm birth at <37 weeks. Two reviewers independently extracted data, and pooled relative risk (RR) with 95% confidence intervals (CIs) was calculated as well. Women with short cervix have a significantly lower risk of preterm birth at <34 weeks (pooled RR = 0.65; 95% CI: 0.55-0.77; I 2 = 0; p < 0.001; nine studies) and some neonatal morbidities; interaction tests showed that effect of vaginal progesterone differs significantly between women with short cervix and those with other risk factors (history of preterm birth, exclusive twin gestation, and vaginal bleeding). Evidences of this study showed that singleton gestations, as well as women with short cervix, benefit from vaginal progesterone in preventing preterm birth at <34 weeks and some neonatal morbidities. Women with short cervix are populations who benefit the most among other risk populations. KEY POINTS: · Vaginal progesterone reduces preterm birth and neonatal morbidities.. · Vaginal progesterone effects on some specific populations.. · Women with short cervix benefit the most..

Are Cervical Pessaries Effective in Preventing Preterm Birth?

Preterm births are a significant concern, as they can have serious consequences for both infants and mothers. It is crucial to identify risk factors associated with preterm birth and to implement effective interventions, such as progesterone, cervical pessary, and cervical cerclage, to prevent it. This systematic review aims to evaluate the efficacy of cervical pessary in reducing spontaneous preterm delivery. However, cervical pessaries have limited research and conflicting findings when compared to other interventions for preventing preterm labor. Therefore, this review seeks to analyze various studies to evaluate their overall effectiveness and better understand their role in treating this vulnerable population. The literature search was conducted using PubMed between January and September 2023, and the systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The results of this review highlight the importance of continued research into mitigation strategies for preterm birth. There is some evidence that indicates that using cervical pessaries before 34 weeks can be effective. While some studies have reported positive outcomes when cervical pessaries are combined with other treatments like progesterone, there is no solid statistical evidence to support this claim. Furthermore, additional research is needed to comprehend the impact of singleton pregnancies and long-term outcomes for both mothers and infants.

Predicting preterm birth using explainable machine learning in a prospective cohort of nulliparous and multiparous pregnant women

Preterm birth (PTB) presents a complex challenge in pregnancy, often leading to significant perinatal and long-term morbidities. "While machine learning (ML) algorithms have shown promise in PTB prediction, the lack of interpretability in existing models hinders their clinical utility. This study aimed to predict PTB in a pregnant population using ML models, identify the key risk factors associated with PTB through the SHapley Additive exPlanations (SHAP) algorithm, and provide comprehensive explanations for these predictions to assist clinicians in providing appropriate care. This study analyzed a dataset of 3509 pregnant women in the United Arab Emirates and selected 35 risk factors associated with PTB based on the existing medical and artificial intelligence literature. Six ML algorithms were tested, wherein the XGBoost model exhibited the best performance, with an area under the operator receiving curves of 0.735 and 0.723 for parous and nulliparous women, respectively. The SHAP feature attribution framework was employed to identify the most significant risk factors linked to PTB. Additionally, individual patient analysis was performed using the SHAP and the local interpretable model-agnostic explanation algorithms (LIME). The overall incidence of PTB was 11.23% (11 and 12.1% in parous and nulliparous women, respectively). The main risk factors associated with PTB in parous women are previous PTB, previous cesarean section, preeclampsia during pregnancy, and maternal age. In nulliparous women, body mass index at delivery, maternal age, and the presence of amniotic infection were the most relevant risk factors. The trained ML prediction model developed in this study holds promise as a valuable screening tool for predicting PTB within this specific population. Furthermore, SHAP and LIME analyses can assist clinicians in understanding the individualized impact of each risk factor on their patients and provide appropriate care to reduce morbidity and mortality related to PTB.

The Role of Genetics in Preterm Birth

Preterm birth (PTB), defined as the birth of a child before 37 completed weeks gestation, affects approximately 11% of live births and is the leading cause of death in children under 5 years. PTB is a complex disease with multiple risk factors including genetic variation. Much research has aimed to establish the biological mechanisms underlying PTB often through identification of genetic markers for PTB risk. The objective of this review is to present a comprehensive and updated summary of the published data relating to the field of PTB genetics. A literature search in PubMed was conducted and English studies related to PTB genetics were included. Genetic studies have identified genes within inflammatory, immunological, tissue remodeling, endocrine, metabolic, and vascular pathways that may be involved in PTB. However, a substantial proportion of published data have been largely inconclusive and multiple studies had limited power to detect associations. On the contrary, a few large hypothesis-free approaches have identified and replicated multiple novel variants associated with PTB in different cohorts. Overall, attempts to predict PTB using single "-omics" datasets including genomic, transcriptomic, and epigenomic biomarkers have been mostly unsuccessful and have failed to translate to the clinical setting. Integration of data from multiple "-omics" datasets has yielded the most promising results.

Sleep deprivation during pregnancy leads to poor fetal outcomes in Sprague-Dawley rats

Sleep deprivation is a common problem during pregnancy, but its impact on the fetus remains unclear. We aimed to investigate the effect of sleep deprivation during pregnancy on fetal outcomes and its mechanism in Sprague-Dawley rats. Sleep deprivation was performed from gestational day(GD) 1-19 using a multiplatform method for 18 h/day. Rats were sacrificed on GD20, and their blood and placentas were collected. Fetal and placental parameters were ascertained. Melatonin, adrenocorticotropic hormone (ACTH) and corticosterone were also measured in serum. The levels of arylalkylamine N-acetyltransferase (AANAT) and two melatonin receptors MT1 and MT2, in placental tissues were detected by western blotting. The inflammatory status and oxidative stress in serum and placentas were investigated. Miscarriage and intrauterine growth restriction were observed in the sleep deprivation group. Sleep deprivation resulted in an increased fetal absorption rate, while fetal weight, crown-rump length and placental weight were reduced. Placental histopathology showed that the labyrinth ratio in the sleep deprivation group was significantly reduced, with hypoplastic villi and obviously decreased blood vessels. Sleep deprivation decreased melatonin in serum and the expression of AANAT, MT1 and MT2 in placental tissues, elevated the oxidative stress products 8-hydroxy-deoxyguanosine (8-OHdG) and malondialdehyde(MDA) in serum and 4-hydroxynonenal (4HNE) in the placenta, and decreased the antioxidants superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in serum. Serum proinflammatory cytokines including interleukin-1-beta (IL-1β), interleukin-6 (IL-6), necrotizing factor-alpha (TNF-α), and interleukin-8(IL-8), were all elevated by sleep deprivation, and the inflammatory regulatory factor nuclear factor-κB p65 (NF-κB p65) in the placenta was enhanced when examined by immunohistochemistry. Corticosterone levels were comparable between the two groups, although ACTH levels were elevated significantly in the sleep deprivation group. Our study revealed that sleep deprivation during pregnancy can adversely impact fetal outcomes. Melatonin may play an important role in this pathology through the oxido-inflammatory process.

Prediction of Preterm Delivery Using Serum Ischemia Modified Albumin, Biglycan, and Decorin Levels in Women with Threatened Preterm Labor

OBJECTIVE

 The serum ischemia modified albumin (IMA), biglycan, and decorin levels of pregnant women who were hospitalized for threatened preterm labor were measured.

METHODS

 Fifty-one consecutive pregnant women with a single pregnancy between the 24th and 36th weeks with a diagnosis of threatened preterm labor were included in the present prospective cohort study.

RESULTS

 As a result of multivariate logistic regression analysis for predicting preterm delivery within 24 hours, 48 hours, 7 days, 14 days, ≤ 35 gestational weeks, and ≤ 37 gestational weeks after admission, area under the curve (AUC) (95% confidence interval [CI[) values were 0.95 (0.89-1.00), 0.93 (0.86-0.99), 0.91 (0.83-0.98), 0.92 (0.85-0.99), 0.82 (0.69-0.96), and 0.89 (0.80-0.98), respectively. In the present study, IMA and biglycan levels were found to be higher and decorin levels lower in women admitted to the hospital with threatened preterm labor and who gave preterm birth within 48 hours compared with those who gave birth after 48 hours.

CONCLUSION

 In pregnant women admitted to the hospital with threatened preterm labor, the prediction preterm delivery of the combined model created by adding IMA, decorin, and biglycan in addition to the TVS CL measurement was higher than the TVS CL measurement alone.

CLINICAL TRIAL REGISTRATION

 The present trial was registered at ClinicalTrials.gov, number NCT04451928.

Cost-effectiveness of history-indicated cerclage vs cervical length assessment for prevention of preterm birth

BACKGROUND

Preterm birth is one of the major causes of neonatal morbidity and mortality. Preterm delivery is a large burden to our health care system, and a history of preterm birth is one of the most common risk factors for subsequent preterm birth.

OBJECTIVE

We sought to examine the cost-effectiveness of the history-indicated cerclage strategy compared with the transvaginal ultrasound cervical length assessment strategy in individuals with a history of preterm birth.

STUDY DESIGN

We developed a decision analysis model to compare history-indicated cerclage and cervical length assessment. The primary outcome was the net monetary benefit from a maternal and neonatal perspective of both strategies, defined as the value of an intervention with a known willingness to pay threshold for a unit of benefit. The time horizon was set to be a lifetime. Costs (in 2022 USD) included those for the cerclage, serial transvaginal ultrasounds, maternal care for admission, neonatal care, and severe disability. Probabilities, utilities, and costs were derived from the literature. A cost-effectiveness threshold was set at $100,000 per QALY (quality-adjusted life year). We first conducted 1-way sensitivity analyses with associated variables as sensitivity analyses. We then performed a probabilistic sensitivity analysis using Monte Carlo simulation with 1000 trials to test the robustness of the results in the setting of simultaneous changes in probabilities, costs, and utilities.

RESULTS

In our base-case analysis, the history-indicated cerclage strategy compared to transvaginal ultrasound cervical length assessment was associated with more cost ($85,038 vs $70,155), with slightly less effectiveness from the maternal perspective (26.74 QALY vs 26.78 QALY) and from the neonatal perspective (28.91 QALY vs 29.06 QALY), and with less maternal and neonatal net monetary benefit. Therefore, the history-indicated cerclage strategy was dominated. With the 1000 trials of Monte Carlo simulation, transvaginal ultrasound cervical length assessment was the preferred strategy 84% and 88% of the time from the maternal and neonatal perspectives, respectively.

CONCLUSION

The history-indicated cerclage strategy was more expensive and slightly less effective than the transvaginal ultrasound cervical length assessment strategy with a lower net monetary benefit.

Trends and risk of recurrent preterm birth in pregnancy cohorts in rural Bangladesh, 1990-2019

INTRODUCTION

A history of preterm birth reportedly increases the risk of subsequent preterm birth. This association has primarily been studied in high-income countries and not in low-income settings in transition with rapidly descending preterm birth figures. We evaluated the population-based trends of preterm births and recurrent preterm births and the risk of preterm birth recurrence in the second pregnancy based on prospectively studied pregnancy cohorts over three decades in Matlab, Bangladesh.

METHODS

A population-based cohort included 72 160 live births from 1990 to 2019. We calculated preterm birth and recurrent preterm birth trends. We assessed the odds of preterm birth recurrence based on a subsample of 14 567 women with live-born singletons in their first and second pregnancies. We used logistic regression and presented the associations by OR with a 95% CI.

RESULTS

The proportion of preterm births decreased from 25% in 1990 to 13% in 2019. The recurrent preterm births had a similar, falling pattern from 7.4% to 3.1% across the same period, contributing 27% of the total number of preterm births in the population. The odds of second pregnancy preterm birth were doubled (OR 2.18; 95% CI 1.96 to 2.43) in women with preterm birth compared with the women with term birth in their first pregnancies, remaining similar over the study period. The lower the gestational age at the first birth, the higher the odds of preterm birth in the subsequent pregnancy (test for trend p<0.001).

CONCLUSION

In this rural Bangladeshi setting, recurrent preterm births contributed a sizeable proportion of the total number of preterm births at the population level. The increased risk of recurrence remained similar across three decades when the total proportion of preterm births was reduced from 25% to 13%.

Addition of cervical elastosonography to cervical length to predict preterm birth in pregnancy women with prior preterm birth: A preliminary prospective study

OBJECTIVES

To investigate the characteristics of cervical elastosonography in pregnancies and establish an ultrasound-based combing predictor for improving the prediction in pregnant women with prior-preterm birth who might ultimately undergo preterm birth (PTB).

MATERIALS AND METHODS

169 singleton pregnancies with prior-preterm birth were examined by cervical elastography from January to November of 2021. According to the ultrasound image and result of the following-up, the patients were separated into preterm groups and full-term groups with or without cerclage. There were five elastographic parameters: Elasticity Contrast Index (ECI), Cervical hard tissue Elasticity Ratio (CHR), External Cervical os Strain rate (ES), Closed Internal Cervical os Strain rate (CIS), CIS/ES ratio and CLmin. Multivariable logistic regression was used to screen out the most significant predictors. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the ability of prediction.

RESULTS

The PTB group without cerclage showed significantly softer cervix stiffness, while those with cerclage showed significantly harder. CHRmin with P < 0.05 in the univariate logistic regression analysis was screened as a more valuable cervical elastosonography parameter than other ones. The combination of CLmin and CHRmin in un-cerclage and integrating CHRmin, maternal age and pre-pregnancy BMI in cerclage presented good predictive value. The results of AUC were higher than CLmin, respectively (0.775 vs 0.734, 0.729 vs 0.548).

CONCLUSIONS

The addition of cervical elastography parameters (such as CHRmin) might improve the ability to predict preterm birth in pregnant women with previous preterm delivery, which was better than using CL alone.

Research prioritisation on prevention and management of preterm birth in low and middle-income countries (LMICs) with a special focus on Bangladesh using the Child Health and Nutrition Research Initiative (CHNRI) method

Background

Fifteen million babies are born preterm globally each year, with 81% occurring in low- and middle-income countries (LMICs). Preterm birth complications are the leading cause of newborn deaths and significantly impact health, quality of life, and costs of health services. Improving outcomes for newborns and their families requires prioritising research for developing practical, scalable solutions, especially in low-resource settings such as Bangladesh. We aimed to identify research priorities related to preventing and managing preterm birth in LMICs for 2021-2030, with a special focus on Bangladesh.

Methods

We adopted the Child Health and Nutrition Research Initiative (CHNRI) method to set research priorities for preventing and managing preterm birth. Seventy-six experts submitted 490 research questions online, which we collated into 95 unique questions and sent for scoring to all experts. A hundred and nine experts scored the questions using five pre-selected criteria: answerability, effectiveness, deliverability, maximum potential for burden reduction, and effect on equity. We calculated weighted and unweighted research priority scores and average expert agreement to generate a list of top-ranked research questions for LMICs and Bangladesh.

Results

Health systems and policy research dominated the top 20 identified priorities for LMICs, such as understanding and improving uptake of the facility and community-based Kangaroo Mother Care (KMC), promoting breastfeeding, improving referral and transport networks, evaluating the impact of the use of skilled attendants, quality improvement activities, and exploring barriers to antenatal steroid use. Several of the top 20 questions also focused on screening high-risk women or the general population of women, understanding the causes of preterm birth, or managing preterm babies with illnesses (jaundice, sepsis and retinopathy of prematurity). There was a high overlap between research priorities in LMICs and Bangladesh.

Conclusions

This exercise, aimed at identifying priorities for preterm birth prevention and management research in LMICs, especially in Bangladesh, found research on improving the care of preterm babies to be more important in reducing the burden of preterm birth and accelerating the attainment of Sustainable Development Goal 3 target of newborn deaths, by 2030.

Acculturation Experiences and Preterm Birth in Berlin: Does Acculturative Stress Contribute to Preterm Birth?

Acculturation and acculturative stress are potential risk factors for adverse perinatal outcomes. This study investigates whether and how acculturative stress affects preterm birth (PTB) in a sample of migrant women in Berlin. We interviewed 955 women who recently gave birth using standardized questionnaires (Frankfurt Acculturation Scale and Acculturative Stress Index). Multivariable logistic regression analyses assessed the effects of acculturation and acculturative stress on PTB. Women with migrant backgrounds did not have significantly higher PTB rates than German natives. First-generation migrants experienced higher acculturative stress levels than second-generation migrants, 38.8% vs. 13.2%. Acculturative stress could not be identified as a risk factor for PTB in our sample. These results need to be considered in the context of an international city and the wide use of antenatal care services in our population, which could be responsible for similarly good perinatal outcomes and highlights the potential of good access to perinatal care for vulnerable groups.

The association between maternal anemia during pregnancy and preterm birth

BACKGROUND & AIMS

Maternal anemia is one of the most serious health problems during pregnancy. The causes of anemia include iron deficiency, parasitic diseases, micronutrient deficiencies, and hereditary hemoglobinopathies. Because the reported association between maternal anemia and preterm labor in different studies is varied depending on the month of pregnancy this study aims to determine this relationship after adjustment for potential confounders.

METHODS

A case-control study was conducted among 801 pregnant women (267 cases and 534 controls) in Sardashat, Iran from October 2012 to October 2013. Hemoglobin (Hb) values were measured for all women participating in the study during the first and second trimesters of pregnancy, and the average Hb values were presented. Statistical analyzes were performed with logistic regression.

RESULTS

The mean age of participants was 26.4 ± 5.25 years for the case group and 27.2 ± 6.51 years for the control group. Preterm birth was associated with maternal anemia during pregnancy [aOR = 2.69 (95% CI; 1.46 to 4.95)] even after adjusting for confounding effects including maternal age, history of abortion [aOR = 2.41 (95% CI; 1.42 to 4.08)], history of preterm birth [aOR = 11.38 (95% CI; 3.48 to 37.22)], obesity (aOR: 3.441; CI95%: 1.18-10.06), parity [aOR = 0.42 (95% CI; 0.25 to 0.69)], preeclampsia/eclampsia [aOR = 6.08 (95% CI; 2.64 to 14)], and GDM [aOR = 4.80 (95% CI; 2.02 to 11.41)]).

CONCLUSION

Early detection and adequate treatment of anemia during pregnancy can help reduce the prevalence of preterm birth.

Third trimester as the susceptibility window for maternal PM2.5 exposure and preterm birth: A nationwide surveillance-based association study in China

Maternal PM_2.5 exposure has been identified as a potential risk factor for preterm birth, yet the inconsistent findings on the susceptible exposure windows may be partially due to the influence of gaseous pollutants. This study aims to examine the association between PM_2.5 exposure and preterm birth during different susceptible exposure windows after adjusting for exposure to gaseous pollutants. We collected 2,294,188 records of singleton live births from 30 provinces of China from 2013 to 2019, and the gridded daily concentrations of air pollutants (including PM_2.5, O₃, NO₂, SO₂, and CO) were derived by using machine learning models for assessing individual exposure. We employed logistic regression to develop single-pollutant models (including PM_2.5 only) and co-pollutant models (including PM_2.5 and a gaseous pollutant) to estimate the odds ratio for preterm birth and its subtypes, with adjustment for maternal age, neonatal sex, parity, meteorological conditions, and other potential confounders. In the single-pollutant models, PM_2.5 exposure in each trimester was significantly associated with preterm birth, and the third trimester exposure showed a stronger association with very preterm birth than that with moderate to late preterm birth. The co-pollutant models revealed that preterm birth might be significantly associated only with maternal exposure to PM_2.5 in the third trimester, and not with exposure in the first or second trimester. The observed significant associations between preterm birth and maternal PM_2.5 exposure in the first and second trimesters in single-pollutant models might primarily be influenced by exposure to gaseous pollutants. Our study provides evidence that the third trimester may be the susceptible window for maternal PM_2.5 exposure and preterm birth. The association between PM_2.5 exposure and preterm birth could be influenced by gaseous pollutants, which should be taken into consideration when evaluating the impact of PM_2.5 exposure on maternal and fetal health.

Risk Scoring Systems for Preterm Birth and Their Performance: A Systematic Review

Introduction: Nowadays, the risk stratification of preterm birth (PTB) and its prediction remain a challenge. Many risk factors associated with PTB have been identified, and risk scoring systems (RSSs) have been developed to face this challenge. The objectives of this systematic review were to identify RSSs for PTB, the variables they consist of, and their performance. Materials and methods: Two databases were searched, and two authors independently performed the screening and eligibility phases. Records studying an RSS, based on specified variables, with an evaluation of the predictive value for PTB, were considered eligible. Reference lists of eligible studies and review articles were also searched. Data from the included studies were extracted. Results: A total of 56 studies were included in this review. The most frequently incorporated variables in the RSS included in this review were maternal age, weight, history of smoking, history of previous PTB, and cervical length. The performance measures varied widely among the studies, with sensitivity ranging between 4.2% and 92.0% and area under the curve (AUC) between 0.59 and 0.95. Conclusions: Despite the recent technological and scientifical evolution with a better understanding of variables related to PTB and the definition of new ultrasonographic parameters and biomarkers associated with PTB, the RSS's ability to predict PTB remains poor in most situations, thus compromising the integration of a single RSS in clinical practice. The development of new RSSs, the identification of new variables associated with PTB, and the elaboration of a large reference dataset might be a step forward to tackle the problem of PTB.

Increased Survival Concomitant with Unchanged Morbidity and Cognitive Disability among Infants Born at the Limit of Viability before 24 Gestational Weeks in 2009-2019

INTRODUCTION

The aim was to determine risk factors among mothers and outcomes for their children born at the limit of viability in 2009-2019, before and after the introduction of extended interventionist guidelines.

METHODS

A retrospective cohort study of births at 22 + 0-23 + 6 gestational weeks in a Swedish Region in 2009-2015 (n = 119), as compared to 2016-2019 (n = 86) after the introduction of new national interventionist guidelines. Infant mortality, morbidity, and cognitive functions at 2 years corrected age according to the Bayley-III Screening Test were monitored.

RESULTS

Maternal risk factors for extreme preterm birth were identified. The intrauterine fetal death rates were comparable. Among births at 22 weeks, the neonatal mortality tended to decrease (96 vs. 76% of live births (p = 0.05)), and the 2-year survival tended to increase (4 vs. 24% (p = 0.05)). Among births at 23 weeks, the neonatal mortality decreased (56 vs. 27% of live births (p = 0.01)), and the 2-year survival increased (42 vs. 64% (p = 0.03)). Somatic morbidity and cognitive disability at 2 years corrected age were unchanged.

CONCLUSION

We identified maternal risk factors that emphasize the need for standardized follow-up and counseling for women at increased risk of preterm birth at the limit of viability. The increased infant survival concomitant with unchanged morbidity and cognitive disability highlight the importance of ethical considerations regarding interventionist approaches at threatening preterm birth before 24 weeks.

Prenatal Diagnosis of Isolated Single Umbilical Artery: Incidence, Risk Factors and Impact on Pregnancy Outcomes

Objectives: To assess the incidence of prenatally diagnosed isolated single umbilical artery (iSUA) and its impact on major pregnancy outcomes, as well as to investigate potential risk factors. Materials and methods: A prospective study of singleton pregnancies, undergoing routine anomaly scans at 20⁺⁰-24⁺⁰ weeks of gestation, was carried out from 2018 to 2022. The effect of sonographically detected iSUA on small-for-gestational-age neonates (SGA) and preterm delivery (PTD) was evaluated using parameterized Student's t-test, nonparametric Mann-Whitney U test and the chi-square test. Multivariable logistic regression models were implemented to assess the independent association between iSUA and the main outcomes, as well as with potential risk factors, while adjusting for specific confounders. Results: The study population included 6528 singleton pregnancies and the incidence of prenatally diagnosed iSUA was 1.3%. Prenatally diagnosed iSUA had a statistically significant association with both SGA neonates (aOR: 1.909; 95% CI: 1.152-3.163) and PTD (aOR: 1.903; 95% CI: 1.035-3.498), while no association was identified between this sonographic finding and preeclampsia. With regard to risk factors, conception via assisted reproductive technology (ART) was associated with increased risk of iSUA (aOR: 2.234; 95% CI: 1.104-4.523), while no other independent predictor for the development of this anatomical variation was identified. Conclusions: Prenatally diagnosed iSUA seems to be associated with a higher incidence of SGA and PTD and is more common in pregnancies following ART, which constitutes a novel finding.

Unmatched spatially stratified controls: A simulation study examining efficiency and precision using spatially-diverse controls and generalized additive models

Unmatched spatially stratified random sampling (SSRS) of non-cases selects geographically balanced controls by dividing the study area into spatial strata and randomly selecting controls from all non-cases within each stratum. The performance of SSRS control selection was evaluated in a case study spatial analysis of preterm birth in Massachusetts. In a simulation study, we fit generalized additive models using controls selected by SSRS or simple random sample (SRS) designs. We compared mean squared error (MSE), bias, relative efficiency (RE), and statistically significant map results to the model results with all non-cases. SSRS designs had lower average MSE (0.0042-0.0044) and higher RE (77-80%) compared to SRS designs (MSE: 0.0072-0.0073; RE across designs: 71%). SSRS map results were more consistent across simulations, reliably identifying statistically significant areas. SSRS designs improved efficiency by selecting controls that are geographically distributed, particularly from low population density areas, and may be more appropriate for spatial analyses.

Development of risk prediction models for preterm delivery in a rural setting in Ethiopia

Background

Preterm birth complications are the leading causes of death among children under five years. However, the inability to accurately identify pregnancies at high risk of preterm delivery is a key practical challenge, especially in resource-constrained settings with limited availability of biomarkers assessment.

Methods

We evaluated whether risk of preterm delivery can be predicted using available data from a pregnancy and birth cohort in Amhara region, Ethiopia. All participants were enrolled in the cohort between December 2018 and March 2020. The study outcome was preterm delivery, defined as any delivery occurring before week 37 of gestation regardless of vital status of the foetus or neonate. A range of sociodemographic, clinical, environmental, and pregnancy-related factors were considered as potential inputs. We used Cox and accelerated failure time models, alongside decision tree ensembles to predict risk of preterm delivery. We estimated model discrimination using the area-under-the-curve (AUC) and simulated the conditional distributions of cervical length (CL) and foetal fibronectin (FFN) to ascertain whether they could improve model performance.

Results

We included 2493 pregnancies; among them, 138 women were censored due to loss-to-follow-up before delivery. Overall, predictive performance of models was poor. The AUC was highest for the tree ensemble classifier (0.60, 95% confidence interval = 0.57-0.63). When models were calibrated so that 90% of women who experienced a preterm delivery were classified as high risk, at least 75% of those classified as high risk did not experience the outcome. The simulation of CL and FFN distributions did not significantly improve models' performance.

Conclusions

Prediction of preterm delivery remains a major challenge. In resource-limited settings, predicting high-risk deliveries would not only save lives, but also inform resource allocation. It may not be possible to accurately predict risk of preterm delivery without investing in novel technologies to identify genetic factors, immunological biomarkers, or the expression of specific proteins.

Unraveling the Efficacy of Therapeutic Interventions for Short Cervix: Insights from a Retrospective Study for Improved Clinical Management

Background and Objectives: Preterm birth (PTB) is associated with important neonatal mortality and morbidity. The aim of this study was to retrospectively evaluate the average treatment effects on the treated and the efficacity of various therapeutic interventions for PTB in a cohort of patients with singleton pregnancies and short cervical lengths. Materials and Methods: This observational retrospective study included 1146 singleton pregnancies at risk of PTB that were segregated into the following groups: intravaginal progesterone (group 1), Arabin pessary (group 2), McDonald cerclage (group 3), intravaginal progesterone and Arabin pessary (group 4), and intravaginal progesterone and cerclage (group 5). Their treatment effects were evaluated and compared. Results: All evaluated therapeutic interventions significantly reduced the occurrence of late and early preterm births. The risk of late and early PTB was lowered for those pregnant patients who received progesterone and pessaries or progesterone and cerclage in comparison with those who received only progesterone. The extremely PTB risk of occurrence was significantly lowered only by the administration of progesterone in association with cervical cerclage in comparison with progesterone monotherapy. Conclusions: The combined therapeutic interventions had the highest efficacy in preventing preterm birth. An individualized evaluation is needed to establish the best therapeutic approach in particular cases.

Impact of maternal obesity on preterm delivery in patients with cervical cerclage

BACKGROUND

Maternal obesity has risen in the United States in recent decades.

OBJECTIVE

This study aimed to evaluate the impact of maternal obesity on the risk for spontaneous preterm delivery and the risk for overall preterm delivery among patients with cervical cerclage placement.

STUDY DESIGN

This was a retrospective study in which data from the California Office of Statewide Health Planning and Development linked birth file from 2007 to 2012 were used, yielding a total of 3654 patients with and 2,804,671 patients without cervical cerclage placement. Exclusion criteria included patients with missing information on body mass index, multiple gestation, anomalous pregnancies, and gestations <20 weeks or >42 weeks. Patients in each group were identified and were further categorized based on body mass index with the nonobese group defined as having a body mass index of <30 kg/m², the obese group defined as having a body mass index of 30 to 40 kg/m², and the morbidly obese group defined as having a body mass index >40 kg/m². The risks for overall and spontaneous preterm delivery were compared between patients without obesity and those with obesity or those with morbid obesity patients. The analysis was stratified by cerclage placement.

RESULTS

Among patients who underwent cerclage placement, the risk for spontaneous preterm delivery was not significantly different in the obese and morbidly obese group when compared with the nonobese group (24.2% vs 20.6%; adjusted odds ratio, 1.18; 95% confidence interval, 0.97-1.43; and 24.5% vs 20.6%; adjusted odds ratio, 1.12; 0.78-1.62, respectively). However, among patients without cerclage placement, the obese and morbidly obese groups had a higher risk for spontaneous preterm delivery than the nonobese group (5.1% vs 4.4%; adjusted odds ratio, 1.04; 1.02-1.05; and 5.9% vs 4.4%; adjusted odds ratio, 1.03; 1.00-1.07, respectively). The risks for overall preterm delivery at <37 weeks' gestation were higher for the obese and morbidly obese groups than for the nonobese group among patients with cerclage (33.7% vs 28.2%; adjusted odds ratio, 1.23; 1.03-1.46; and 32.1% vs 28.2%; adjusted odds ratio, 1.01; 0.72-1.43, respectively). Similarly, among patients without cerclage placement, the risks for preterm delivery at <37 weeks' gestation were higher for the obese and morbidly obese groups than for the nonobese group (7.9% vs 6.8%; adjusted odds ratio, 1.05; 1.04-1.06; and 9.3% vs 6.8%; adjusted odds ratio, 1.10; 1.08-1.13, respectively).

CONCLUSION

Among patients who received a cervical cerclage for the prevention of preterm birth, obesity was not associated with an increased risk for spontaneous preterm delivery. However, it was associated with an overall increased risk for preterm delivery.

Reported health, social support, stress and associations with choline intake in pregnant women in central South Africa: the NuEMI study 2018-2019

BACKGROUND

The health and well-being of pregnant women can influence pregnancy outcomes and are closely associated with social support and experiences of stress. Poor nutrition predisposes to poor health with choline intake affecting pregnancy outcome. This study determined reported health, social support, and stress and how these factors are associated with choline intake in pregnancy.

METHODS

A cross sectional study was performed. Pregnant women in their second and third trimesters attending a high-risk antenatal clinic at a regional hospital in Bloemfontein, South Africa, were included. Trained fieldworkers obtained information during structured interviews using standardised questionnaires. Logistic regression with backward selection (p < 0.05) was used to select significant independent factors associated with choline intake. Variables with a p-value < 0.15 in bivariate analysis were considered for inclusion in the model.

RESULTS

Median age and gestation in the sample (N = 682) were 31.8 years and 32.0 weeks, respectively. Most participants (84.7%) consumed less than the adequate intake (AI) of 450 mg of choline per day. Most participants (69.0%) were either overweight or obese. One in eight participants (12.6%) reported not having anyone that could help them in times of need, more than one third (36.0%) reported having unpayable debt and one in twelve (8.4%) reported experiencing physical abuse by their partners. Normotensive participants and those using anti-retroviral therapy (ART) (thus HIV-infected), were more likely to consume choline in amounts below the AI (p = 0.042 and p = 0.011, respectively). Logistic regression analysis showed that the odds of consuming choline in amounts below the AI were lower for participants that were not using ART versus those using ART, with an odds ratio of 0.53.

CONCLUSION

HIV-infected participants were more likely to consume choline in levels below the AI. This vulnerable group should be the focus of targeted efforts to improve choline intake.

Temporal trends in adverse pregnancy outcomes in axial spondyloarthritis in Sweden: a cohort study

BACKGROUND

Evidence on the risks associated with pregnancy and childbirth in women with axial spondyloarthritis is scarce and conflicting, with more research needed to guide policy and clinical practice. We aimed to assess the risks of adverse pregnancy outcomes in a large cohort of women with axial spondyloarthritis, and to investigate how outcomes varied over time and in relation to anti-rheumatic treatment.

METHODS

In this register-based cohort study, we included births in Sweden between April 1, 2007, and Dec 31, 2020, to women with axial spondyloarthritis and general population comparators, matched 1:10 on year of delivery, maternal age, and parity. Our main data source was the Medical Birth Register (MBR), which includes over 98% of births in Sweden and prospectively collects data on antenatal care, delivery, and foetal outcomes. The information in MBR was linked to other registers, including the National Patient Register, the Prescribed Drug Register, and registers with demographic data. Our main outcomes were the relative risks of adverse pregnancy outcomes, analysed using modified Poisson regression. We also studied how the frequency of certain adverse outcomes, as well as disease-modifying antirheumatic drug (DMARD) and non-steroidal anti-inflammatory drug treatments, changed over the study period by linear regression and loess plots.

FINDINGS

Between April 1, 2007, and Dec 31, 2020, 1580 births in women with axial spondyloarthritis recorded in MBR fulfilled the inclusion criteria and were matched with 15 792 comparator births. Among the 1580 births in women with axial spondyloarthritis, we found increased risks of preterm birth (risk ratio 1·43, 95% CI 1·13-1·80), pre-eclampsia (1·44, 1·08-1·92), elective caesarean delivery (1·59, 1·37-1·84), and serious infant infection (1·29, 1·05-1·59) compared with births in general population comparators. The risks of preterm birth, infant infection, and caesarean delivery decreased by around 0·5 percentage points annually during the study period, while the use of tumour necrosis factor inhibitors during pregnancy increased.

INTERPRETATION

In view of remaining concerns regarding safety of the use of biological DMARDs during pregnancy, we saw a reassuring trend in which pregnancy outcomes improved over time in the axial spondyloarthritis group, concurrent with increased use of biological DMARDs. If the current rate of improvement is maintained, women with axial spondyloarthritis treated in accordance with clinical guidelines might eventually not be at an increased risk of adverse pregnancy outcomes.

FUNDING

Swedish Research Council and The Swedish Rheumatism Association.

Progesterone, cerclage, pessary, or acetylsalicylic acid for prevention of preterm birth in singleton and multifetal pregnancies - A systematic review and meta-analyses

Background

Preterm birth is the leading cause of childhood mortality and morbidity. We aimed to provide a comprehensive systematic review on randomized controlled trials (RCTs) on progesterone, cerclage, pessary, and acetylsalicylic acid (ASA) to prevent preterm birth in asymptomatic women with singleton pregnancies defined as risk of preterm birth and multifetal pregnancies.

Methods

Six databases (including PubMed, Embase, Medline, the Cochrane Library) were searched up to February 2022. RCTs published in English or Scandinavian languages were included through a consensus process. Abstracts and duplicates were excluded. The trials were critically appraised by pairs of reviewers. The Cochrane risk-of-bias tool was used for risk of bias assessment. Predefined outcomes including preterm birth, perinatal/neonatal/maternal mortality and morbidity, were pooled in meta-analyses using RevMan 5.4, stratified for high and low risk of bias trials. The certainty of evidence was assessed using the GRADE approach. The systematic review followed the PRISMA guideline.

Results

The search identified 2,309 articles, of which 87 were included in the assessment: 71 original RCTs and 16 secondary publications with 23,886 women and 32,893 offspring. Conclusions were based solely on trials with low risk of bias (n = 50).Singleton pregnancies: Progesterone compared with placebo, reduced the risk of preterm birth <37 gestational weeks: 26.8% vs. 30.2% (Risk Ratio [RR] 0.82 [95% Confidence Interval [CI] 0.71 to 0.95]) (high certainty of evidence, 14 trials) thereby reducing neonatal mortality and respiratory distress syndrome. Cerclage probably reduced the risk of preterm birth <37 gestational weeks: 29.0% vs. 37.6% (RR 0.78 [95% CI 0.69 to 0.88]) (moderate certainty of evidence, four open trials). In addition, perinatal mortality may be reduced by cerclage. Pessary did not demonstrate any overall effect. ASA did not affect any outcome, but evidence was based on one underpowered study.Multifetal pregnancies: The effect of progesterone, cerclage, or pessary was minimal, if any. No study supported improved long-term outcome of the children.

Conclusion

Progesterone and probably also cerclage have a protective effect against preterm birth in asymptomatic women with a singleton pregnancy at risk of preterm birth. Further trials of ASA are needed. Prevention of preterm birth requires screening programs to identify women at risk of preterm birth.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021234946].

Adherence to recommended physical activity restrictions due to threatened preterm delivery - a descriptive multi-center study

BACKGROUND

Threatened preterm delivery is a serious obstetrical complication and has for decades been prescribed physical activity restrictions (AR). Adherence to the recommended level of physical AR is however unknown. This study aimed to assess the objectively measured different physical positions and activities of pregnant women recommended AR due to threatened preterm delivery complications, compared to a reference group of uncomplicated pregnant women without restrictions, and to explore if admission status influenced adherence to AR.

METHODS

A Danish descriptive, clinical multi-center study included singleton pregnancies between 22-33 gestational weeks admitted to an antenatal ward or during midwife consultations either prescribed AR due to threatened preterm delivery or uncomplicated controls without restrictions. For seven days participants wore two tri-axial accelerometric SENS® monitors. Accelerometric data included time spent in five different positions, activities, and step counts. At inclusion demographic and obstetric information was collected.

RESULTS

Seventy-two pregnant women participated; 31% were prescribed strict AR, 15% moderate, 3% light, 8% unspecified, and 43% had no AR. Strict AR participants rested in the supine/lateral position for 17.7 median hours/day (range:9.6-24.0); sat upright 4.9 h/day (0.11-11.7); took 1,520steps/day (20-5,482), and 64% were inpatients. Moderate AR participants rested in the supine/lateral position for 15.1 h/day (11.5-21.6); sat upright 5.6 h/day (2.0-9.3); took 3,310steps/day (467-6,968), and 64% were outpatients. Participants with no AR rested 10.5 h/day (6.3-15.4) in supine/lateral position; sat upright 7.6 h/day (0.1-11.4) and took 9,235steps/day (3,225-20,818). Compared to no restrictions, participants with strict or moderate AR spent significant more time in physical resting positions and took significant fewer mean steps. Among strict AR admission status did not alter time spent in the physical positions, nor the step count.

CONCLUSIONS

Overall, participants adhered highly to the recommended AR. However, discriminating between strict and moderate AR recommendations did not alter how physical resting positions and activities were carried out. The admission status did not influence how participants adhered to strict AR.

DYNAMICS OF MISCARRIAGE AMONG THE FEMALE POPULATION OF FERTILE AGE IN UKRAINE AND IN LVIV REGION IN 2014-2021

Aim. The research aims at rationalizing of the epidemiological component in the process of developing a model for preventing miscarriage among the female population of Ukraine. Materials and Methods. A retrospective analysis of the indicators of miscarriage among the female population of Ukraine and Lviv region for the period from 2014 to 2021 was carried out. Statistical data of the Center for Medical Statistics of the Ministry of Health of Ukraine were used, namely Form No. 21 "Report on medical care for pregnant women, women in labor and women giving birth". The study uses the methods of a systemic approach and structural-logical analysis, medical-statistical analysis, namely the calculation of chain (relative to the previous year) indicators of a dynamic series: absolute growth, growth rate and increment rate. Results and Discussion. A decrease in the female population of fertile age by 13.03% in Ukraine and by 5.81% in Lviv region was noted in the analyzed period of 2014-2021, while the number of spontaneous abortions in Ukraine decreased by an average of 3.45% per year, and grew in Lviv region in 2015, 2018, 2019 and 2020 by 5.72%, 6.87%, 19.29% and 6.59%, respectively. The rates of spontaneous abortions per 1,000 women of fertile age in Lviv region were twice as low as in Ukraine. Over the analyzed 8-year period, the share of premature children among all live births increased from 4.68% to 5.68% in Ukraine, and from 4.18% to 5.65% in Lviv region, respectively; these indicators in Lviv region were smaller compared to the indicators in Ukraine. The share of premature babies among stillbirths averaged 63.07% in Ukraine and 67.69% in Lviv region, had a growing trend, and the indicators in Lviv region were higher every year compared to the indicators in Ukraine. The ratio of the total rate of miscarriage to the total number of pregnancies (cases of miscarriage per 100 pregnancies) increased from 5.50 in 2014 to 6.22 in 2021 in Ukraine and from 3.57 to 4.72 in Lviv region respectively. Conclusions. There was a trend of annual increase in the index of the ratio of the total miscarriage rate to the total number of pregnancies, the share of prematures from the total number of live births and the share of premature births from the number of stillbirths in the analyzed 8-year period, both in Ukraine and in Lviv region. The analyzed indicators of the share of premature newborns from the total number of live births in Lviv region were lower every year, and the share of newborns from the total number of stillbirths was higher compared to the average annual indicators in Ukraine. The dynamics of spontaneous abortions showed a clear trend towards an annual decrease in Ukraine and their increase in 2015, 2018-2020 in Lviv region. The rate of spontaneous abortions among women of fertile age in Lviv region from 2014 to 2021 was annually half as low compared to the average annual levels of this indicator in Ukraine.

Development of prognostic model for preterm birth using machine learning in a population-based cohort of Western Australia births between 1980 and 2015

Preterm birth is a global public health problem with a significant burden on the individuals affected. The study aimed to extend current research on preterm birth prognostic model development by developing and internally validating models using machine learning classification algorithms and population-based routinely collected data in Western Australia. The longitudinal retrospective cohort study involved all births in Western Australia between 1980 and 2015, and the analytic sample contains 81,974 (8.6%) preterm births (< 37 weeks of gestation). Prediction models for preterm birth were developed using regularised logistic regression, decision trees, Random Forests, extreme gradient boosting, and multi-layer perceptron (MLP). Predictors included maternal socio-demographics and medical conditions, current and past pregnancy complications, and family history. Class weight was applied to handle imbalanced outcomes and stratified tenfold cross-validation was used to reduce overfitting. Close to half of the preterm births (49.1% at 5% FPR, 95% CI 48.9%,49.5%) were correctly classified by the best performing classifier (MLP) for all women when current pregnancy information was available. The sensitivity was boosted to 52.7% (95% CI 52.1%,53.3%) after including past obstetric history in a sub-population of births from multiparous women. Around half of the preterm birth can be identified antenatally at high specificity using population-based routinely collected maternal and pregnancy data. The performance of the prediction models depends on the available predictor pool that is individual and time specific.