Risk Factors For Preterm Birth Research Articles

Estimating the individual singleton preterm birth risk: nomogram establishment and independent validation.

To establish and independently validate nomograms for predicting singleton preterm birth (PTB) risk based on a large sample size comprising data from two independent datasets. This cohort study used data from 50 states and the District of Columbia in the National Vital Statistics System (NVSS) database between January 2016 and December 2020. Multivariate logistic regression analysis was used to confirm the independent risk factors for PTB. Statistically significant variables were incorporated into the logistic regression models to establish PTB prediction nomograms. The models were developed using the United States (US)-derived data and were independently validated using data from US Territories. A total of 16,294,529 mother-newborn pairs from the US were included in the training set, and 54,708 mother-newborn pairs from the US Territories were included in the validation set. In all, 4 nomograms were built: 1 to predict PTB probability, and another 3 to predict moderately and late PTB probability, very PTB probability, and extremely PTB probability, respectively. Hypertensive eclampsia and infertility treatment were found to be the top 2 contributors to PTB. We developed and validated nomograms to predict the individualized probability of PTB, which could be useful to physicians for improved early identification of PTB and in making individualized clinical decisions.

Differences in Vaginal Progesterone Provision among Racial and Socioeconomic Groups

Objective: Preterm birth is the leading cause of perinatal morbidity and mortality and has been increasing in the United States. Short cervical length is a treatable risk factor for preterm birth. Non-Hispanic black and Hispanic women have significantly higher rates of preterm birth and disparities exist in the obstetrical care of these populations.

The Awareness of Females About Risk Factors That Lead to Having a Baby With Congenital Heart Disease in Taif, Saudi Arabia.

Background There is limited data on the awareness of risk factors associated with congenital heart diseases in Saudi Arabia. This study assesses females' knowledge of the risk factors that lead to giving birth to a child with congenital heart disease in Taif, Saudi Arabia. Methodology A cross-sectional study was done on 254 females. An online questionnaire was used to collect data about the participants' demographics and their knowledge of risk factors that lead to having a baby with congenital heart disease, including risks such as smoking, drinking alcohol, taking unprescribed medication, exercising, contracting German measles, developing thyroid disease, and not taking vitamins and folic acid, as well as genetic factors such as high blood pressure, diabetes, obesity, consanguineous marriage, advanced maternal age, and eating unhealthy food. Results The most common risk factors linked to newborns with congenital heart disorders (CHDs) are alcohol consumption (98.4%), smoking (96%), genetics (86.6%), high blood pressure (82.3%), diabetes (78.4%), and taking medication during pregnancy (74.4%). A little over 73.3% of the participants were aware that risk factors for preterm birth included not taking vitamins and folic acid during pregnancy, obesity (68.9%), contracting German measles while pregnant (68.5%), consanguineous marriage (62.2%), developing thyroid disease during pregnancy (56.7%), and advanced maternal age (50%); 11.4%, 46.1%, and 42.5% of the participants had poor, fair, and good understanding, respectively, of the risk factors for having a baby with congenital cardiac disease. There was no significant correlation between the participants' demographic characteristics and their levels of awareness. Conclusion There is a need for public programs to increase awareness about the risk factors associated with congenital heart diseases.

Impact of exposure to air pollution on cervicovaginal microbial communities

PurposeVaginal microbial communities can be dominated by anaerobic (community state type IV, CST IV) or Lactobacillus (other CSTs) species. CST IV is a risk factor for spontaneous preterm birth (sPTB) and is more common among Black than White populations. In the US, average air pollution exposures are higher among Black compared to White people and exert systemic health effects. We sought to (1) quantify associations of air pollution, specifically particulate matter <2.5 μm in diameter (PM2.5), with CST IV and (2) explore the extent to which racial disparities in PM2.5 exposure might explain racial differences in the prevalence of CST IV. DesignMethods: We performed a secondary analysis of 566 participants of the Motherhood & Microbiome study. PM2.5 exposures were derived from a machine learning model integrating NASA satellite and EPA ground monitor data. Previously, cervicovaginal swabs from 15 to 20 weeks’ gestation were analyzed using 16 S rRNA sequencing and hierarchical clustering assigned CSTs. Multivariable logistic regression models calculated adjusted odds ratios of CST IV (vs. other CSTs) per interquartile range (IQR) increment of PM2.5. Race-stratified and mediation analyses were performed. ResultsHigher PM2.5 exposure was associated with CST IV (aOR 1.39, 95% CI 1.02–1.91). Further adjustment for race/ethnicity attenuated the association (aOR 1.34, 95% CI: 0.97–1.83). Black participants (vs. White) had higher median PM2.5 exposure (10.6 vs. 9.6 μg/m3, P < 0.001) and higher prevalence of CST IV (47% vs. 11%, P < 0.001). Mediation analysis revealed that higher PM2.5 exposure may explain 3.9% (P = 0.038) and 3.3% (P = 0.15) of the Black-White disparity in CST IV in unadjusted and adjusted models, respectively. ConclusionPM2.5 was associated with CST IV, a risk factor for sPTB. Additionally, PM2.5 exposure may partially explain racial differences in the prevalence of CST IV. Further research is warranted to discover how environmental exposures affect microbial composition and perpetuate racial health disparities.

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

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. 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. 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. 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. 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.

Effects of ambient temperature and relative humidity on preterm birth during early pregnancy and before parturition in China from 2010 to 2018: a population-based large-sample cohort study.

The progression of global warming and increase in instances of extreme weather have received considerable attention. We conducted a cohort study on women of childbearing age in Yunnan Province, examined the association between ambient temperature and humidity on preterm birth and evaluated the effects of extreme weather during early pregnancy and before parturition on preterm birth. We conducted a population-based cohort study on women of childbearing age 18-49 years who participated in National Free Preconception Health Examination Project (NFPHEP) in Yunnan Province from January 1, 2010, to December 31, 2018. Meteorological data, namely daily average temperature (°C) and daily average relative humidity (%), were obtained from China National Meteorological Information Center. Four exposure windows were explored: 1 week of pregnancy, 4 weeks of pregnancy, 4 weeks before delivery, and 1 week before delivery. We used a Cox proportional hazards model and adjusted the potential risk factors for preterm birth to obtain the effects of exposure to temperature and humidity on preterm birth among the stages of pregnancy. At 1 week of pregnancy and at 4 weeks of pregnancy, the association between temperature and preterm birth was U-shaped. The correlation between relative humidity and the risk of preterm birth was n-type at 1 week of pregnancy. The correlation between preterm birth and temperature and relative humidity at 4 weeks before delivery and at 1 week before delivery is J-shaped. Low temperature and low humidity were protective factors against preterm birth, whereas high temperature and high humidity were risk factors for preterm birth.The effects of high temperature and extremely high temperature were the strongest at 4 weeks before delivery, with HRs of 1.417 (95% CI: 1.362-1.474) and 1.627 (95% CI: 1.537-1.722), respectively. The effects of extremely low humidity and low humidity were strongest at 1 week before delivery, with HRs of 0.681 (95% CI: 0.609-0.761) and 0.696 (95% CI: 0.627-0.771), respectively. Temperature and relative humidity affect preterm birth differently for each pregnancy stage. The effects of meteorological factors on pregnancy outcomes such as premature birth should not be ignored.

Association between preterm birth and low birth weight and maternal chronic periodontitis: A hospital-based case-control study.

Periodontal diseases (PDs) are one of the most common chronic diseases affecting overall oral functions, and their association with adverse pregnancy outcomes (APOs) has been an area of interest since the late 90s. The present hospital-based case-control study aimed to find any association between maternal chronic periodontitis (CP) and preterm birth (PTB) and low birth weight (LBW) by comparing the periodontal parameters in patients with normal birth, PTB and LBW. The participants of the study were females that had delivered a live baby (n = 1,200). They were classified as either cases or controls. The cases were defined as PTB if the delivery was before 37 weeks of gestation, and as LBW if the infant weighed <2,500 g. The others were controls. The intraoral examination, which included recording the periodontal status, was conducted within 3 days of delivery. Detailed medical history and demographic data were recorded for the determination of the confounding factors. The multivariable dependence of PTB and LBW on both the categorical and continuous data was analyzed using a multivariate logistic regression analysis. Adjusted odds ratios (AORs) with a 95% confidence interval (CI) for the risk of PTB and LBW were calculated. A strong association with PTB was found for a high plaque index (PI) score (AOR = 1.61; p < 0.001; 95% CI: 1.26-2.07) and a mean pocket probing depth (PPD) ≥4 mm (AOR: 4.32; p < 0.001; 95% CI: 3.09-6.02). A strong association with LBW was found for a high PI score (AOR = 2.02; p < 0.001; 95% CI: 1.43-2.83) and a mean PPD ≥4 mm (AOR: 8.70; p < 0.001; 95% CI: 6.01-12.59). A high PI score and a mean PPD ≥4 mm were independent risk factors for PTB and LBW. The presence of deep pockets and inadequate plaque control in pregnant females increased the risk of APOs.

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

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. 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. 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. 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.

Association between season of conception, month of conception with preterm birth in China: a population-based retrospective cohort study

BackgroundSeasonal patterns of preterm birth were identified in previous studies, but the effect of conception season on preterm birth has not been extensively studied. Based on the notion that the etiological roots of preterm birth lie in the beginning of pregnancy, we did a population-based retrospective cohort study in Southwest China to examine the effects of season of conception and month of conception on preterm birth.MethodsWe did a population-based retrospective cohort study in women (aged 18–49) who participated in the NFPHEP from 2010 to 2018, and had a singleton livebirth in southwest China. According to the time of the last menstruation reported by the participants, month of conception and season of conception were then ascertained. We used multivariate log-binomial model to adjust the potential risk factors for preterm birth and obtained adjusted risk ratio (aRR) and 95% confidence intervals (95%CI) for conception season, conception month and preterm birth.ResultsAmong 194 028 participants, 15 034 women had preterm birth. Compared with pregnancies that were conceived in the summer, pregnancies that were conceived in the spring, autumn and winter had the higher risk of preterm birth (Spring: aRR = 1.10, 95% CI: 1.04–1.15; Autumn: aRR = 1.14, 95% CI: 1.09–1.20; Winter: aRR = 1.28, 95% CI: 1.22–1.34) and also had a higher risk of early preterm birth (Spring: aRR = 1.09, 95% CI: 1.01–1.18; Autumn: aRR = 1.09, 95% CI: 1.01–1.19; Winter: aRR = 1.16, 95% CI: 1.08–1.25). Pregnancies in December, and January had a higher risk of preterm birth and early preterm birth than pregnancies that were conceived in July.ConclusionsOur study found that preterm birth was significantly related to season of conception. Preterm and early preterm birth rates were the highest among pregnancies that were conceived in winter, and the lowest among pregnancies in summer.

Prevalence of complications associated with premature births in Khyber Pakhtunkhwa

Objectives: This cross-sectional study was executed in three districts of Khyber Pakhtunkhwa (Abbottabad, Peshawar and Charsada), from April 2021 to January 2023, to determine the complications associated with premature births. Methods: The study comprised 339 preterm infants, including 175 male and 164 female infants. All the demographic features of the mother for assessment of the potential risk factors for preterm births along with the initial fetal weights were recorded in the delivery room, and the complications of preterm births were also recorded. Results: Maternal demographic features revealed that a significant proportion of women (p&lt;0.05) pertained to age group of 30-40 years (42.18%), subsequently 20-30 years (31.56%), below 20 years (17.99%) and above 40 years (8.25%). A significant number of women who gave birth to premature babies (p&lt;0.05) were in their Multiparous phase (82.01%) and sixty-one women were in their Primiparous stage (17.99%). Most of the women were emaciated (p&lt;0.05) and had poor health status (59.58%), while, 12.38% had moderate health. It was evident from the findings that there was a non-significant correlation among the gestational groups (p≥0.05), in which a maximum number of patients were lying in very mature infants (56.63%), followed by moderately premature (28.90%) and extremely preterm (14.45%).

The Effect of Sexual Intercourse during Pregnancy on Preterm Birth: Prospective Single-Center Cohort Study in Japan.

Several studies in Europe and the United States have shown that sexual intercourse (SI) during pregnancy is not associated with preterm birth. However, it is unclear whether these findings apply to pregnant Japanese women. The aim of this prospective cohort study was to elucidate the influence of SI during pregnancy on preterm birth in Japan. A total of 182 women who underwent antenatal care and delivery were included in this study. The frequency of SI was assessed using a questionnaire, and its association with preterm birth was analyzed. The results showed that SI during pregnancy was associated with a significantly higher cumulative preterm birth rate (p = 0.018), which was more pronounced for SI more than once a week (p < 0.0001). Multivariate analysis showed that SI, bacterial vaginosis in the second trimester, previous preterm birth, and smoking during pregnancy were independent risk factors for preterm birth. The combination of SI and second trimester bacterial vaginosis was associated with a 60% preterm birth rate, whereas either factor alone was associated with a lower rate, suggesting a synergistic effect (p < 0.0001). Future studies are needed to investigate the effect of prohibiting SI in pregnant women with bacterial vaginosis on preterm birth.

Preterm birth risk in mother with hypertensive disorders of pregnancy

Preterm birth (PTB) is a major public health concern and is the leading cause of under-5 child mortality. Some studies suggest that hypertension disorders of pregnancy (HDP) play an important role in causing PTB. HDP is a term that includes chronic hypertension (CH), gestational hypertension (GH), and pre-eclampsia (PE). The association between the various types of HDP and PTB has not been studied specifically in prior research, yet. Therefore, the purpose of this study is to analyze risk differences among HDP types. This study was carried out in Makassar's Maternal and Child Hospital using a case-control study design. A sample consisting of 138 cases and 276 controls was collected from the medical record data. Odds ratio and logistic regression test analysis were used to obtain both crude OR (COR) and adjusted OR (AOR). The finding shows that regardless of its type, HDP is a major risk factor for preterm birth. The findings also indicated that PTB risk differs depending on the type of HDP suffered. CH had the highest risk (COR=5.61; AOR=6.58), followed by PE (COR=3.36; OR=3.18) and GH (COR=3.46; AOR=3.09), which have fairly similar risks. CH which has the greatest risk needs to be considered to be the focus of prevention. While in the context of preventing preterm delivery, GH and PE need to receive the same attention. However, prevention and treatment must still be adjusted depending on the type of hypertension suffered.

Eclampsia, in vitro fertilization and the risk of preterm birth: a retrospective cohort study based on 2,880,759 samples.

Eclampsia and in vitro fertilization (IVF) are independent risk factors for preterm birth. Understanding the combined effects of multiple risk factors for preterm birth is critical to making accurate and personalized risk predictions. This study aimed to explore the interaction between eclampsia and IVF on the risk of preterm birth. A total of 2,880,759 eligible participants from Birth Data Files in the National Vital Statistics System (NVSS) database 2019 were enrolled in this retrospective cohort study. Some characteristics were collected, such as maternal age, prepregnancy body mass index (BMI), history of preterm birth, paternal age, race, newborn sex. Preterm birth was defined as <37 weeks gestation. Univariate and multivariate logistic regression models were utilized to assess the associations between eclampsia, IVF and preterm birth. The odds ratio (OR) and 95% confidence interval (CI) were calculated in this study. Relative excess risk due to interaction (RERI), attributable proportion (AP) and synergy index (S) were adopted to evaluate the interaction between eclampsia and IVF on the risk of preterm birth. The age of mothers and fathers, the number of multiple births, the proportion of mothers with a history of preterm birth, pregnancy infections, eclampsia and IVF among the preterm birth group were all higher than those among the non-preterm birth group. The incidence of preterm birth in eclampsia and IVF population was approximately 37.31% and 22.96%, separately. After adjusting some covariates, subjects with both eclampsia and IVF had a higher risk of preterm birth (OR =9.197, 95% CI: 6.795-12.448, P<0.001). Furthermore, the results (RERI =3.426, 95% CI: 0.639-6.213, AP=0.374, 95% CI: 0.182-0.565, S =1.723, 95% CI: 1.222-2.428) suggested that the interaction between eclampsia and IVF on preterm birth was statistically significant, indicating a synergistic interaction. Eclampsia and IVF might interact in a synergistic manner to increase the risk of preterm birth. Awareness of the risk profile associated with preterm birth is crucial for pregnant woman with IVF to implement dietary and lifestyle modifications.

Maternal SARS-COV-2 infection and prematurity: the Southern Michigan COVID-19 collaborative

Objective COVID-19 has been reported to increase the risk of prematurity, however, due to the frequent absence of unaffected controls as well as inadequate accounting for confounders in many studies, the question requires further investigation. We sought to determine the impact of COVID-19 disease on preterm birth (PTB) overall, as well as related subcategories such as early prematurity, spontaneous, medically indicated preterm birth, and preterm labor (PTL). We assessed the impact of confounders such as COVID-19 risk factors, a-priori risk factors for PTB, symptomatology, and disease severity on rates of prematurity. Methods This was a retrospective cohort study of pregnant women from March 2020 till October 1st, 2020. The study included patients from 14 obstetric centers in Michigan, USA. Cases were defined as women diagnosed with COVID-19 at any point during their pregnancy. Cases were matched with uninfected women who delivered in the same unit, within 30 d of the delivery of the index case. Outcomes of interest were frequencies of prematurity overall and subcategories of preterm birth (early, spontaneous/medically indicated, preterm labor, and premature preterm rupture of membranes) in cases compared to controls. The impact of modifiers of these outcomes was documented with extensive control for potential confounders. A p value <.05 was used to infer significance. Results The rate of prematurity was 8.9% in controls, 9.4% in asymptomatic cases, 26.5% in symptomatic COVID-19 cases, and 58.8% among cases admitted to the ICU. Gestational age at delivery was noted to decrease with disease severity. Cases were at an increased risk of prematurity overall [adjusted relative risk (aRR) = 1.62 (1.2–2.18)] and of early prematurity (<34 weeks) [aRR = 1.8 (1.02–3.16)] when compared to controls. Medically indicated prematurity related to preeclampsia [aRR = 2.46 (1.47–4.12)] or other indications [aRR = 2.32 (1.12–4.79)], were the primary drivers of overall prematurity risk. Symptomatic cases were at an increased risk of preterm labor [aRR = 1.74 (1.04–2.8)] and spontaneous preterm birth due to premature preterm rupture of membranes [aRR = 2.2(1.05–4.55)] when compared to controls and asymptomatic cases combined. The gestational age at delivery followed a dose-response relation with disease severity, as more severe cases tended to deliver earlier (Wilcoxon p < .05). Conclusions COVID-19 is an independent risk factor for preterm birth. The increased preterm birth rate in COVID-19 was primarily driven by medically indicated delivery, with preeclampsia as the principal risk factor. Symptomatic status and disease severity were significant drivers of preterm birth.

Association of chorioamnionitis with infertility treatment and subsequent neonatal outcomes in the US: a population-based cohort study

BackgroundChorioamnionitis (CAM) is a common risk factor for preterm births, resulting in several adverse outcomes. The association between infertility treatment and CAM is unclear. Therefore, this study examined the association between infertility treatment and CAM and described subsequent neonatal outcomes.MethodsThis population-based cohort study used data from the National Vital Statistics System Database. We included women who had a singleton live birth from January 1, 2016 to December 31, 2018. Women-infant pairs were stratified by infertility treatment, and the main outcome was a reported diagnosis of CAM in a checkbox format: clinical CAM or maternal temperature of > 38 °C. Multivariate logistic regression was used to examine the association between infertility treatment and CAM and the effect of infertility treatment on neonatal outcomes in women diagnosed with CAM.ResultsThe final sample comprised 10,900,495 woman-infant pairs, and 1.4% received infertility treatment. Compared with the natural conception group, women receiving infertility treatment had a significantly higher risk of CAM (adjusted odds ratio [aOR] 1.772 [95% confidence interval {CI}, 1.718–1.827]). Furthermore, newborns exposed to CAM had a higher risk of very low birth weight (VLBW) (aOR, 2.083 [95% CI, 1.664–2.606], P < .001), preterm birth (aOR, 1.497 [95% CI, 1.324–1.693]; P < .001), neonatal intensive care unit admission (aOR, 1.234 [95% CI, 1.156–1.317]; P < .001), and other adverse neonatal outcomes in the infertility treatment group compared with ones conceived naturally.ConclusionsThis study found that women who received infertility treatment had a higher risk of CAM. And CAM deteriorated neonatal outcomes in the infertility treatment group.

Maternal, obstetric and gynecological factors associated with preterm birth in Rwanda: findings from a national longitudinal study

BackgroundPreterm birth is one of the key causes of morbidity and mortality among neonates in low-income countries. In Rwanda, at least 35,000 babies are born prematurely each year, and 2600 children under the age of five die due to direct complications of prematurity each year. A limited number of studies have been conducted locally, many of which are not nationally representative. Thus, this study determined the prevalence as well as the maternal, obstetric, and gynecological factors associated with preterm birth in Rwanda at the national level.MethodsA longitudinal cohort study was conducted from July 2020 to July 2021 among first-trimester pregnant women. A total of 817 women from 30 health facilities in 10 districts were included in the analysis. A pre-tested questionnaire was used to collect data. In addition, medical records were reviewed to extract relevant data. Ultrasound examination was used to assess and confirm gestational age on recruitment. A multivariable logistic regression analysis was performed to determine the independent maternal, obstetric, and gynecological factors associated with preterm birth.ResultsThe prevalence of preterm births was 13.8%. Older maternal age- 35 to 49 years [Adjusted odds ratio (AOR) = 2.00; 95% Confidence Interval (CI) = 1.13–3.53)], secondhand smoke exposure during pregnancy (AOR = 1.91; 95% CI = 1.04–3.51), a history of abortion (AOR = 1.89; 95% CI = 1.13–3.15), premature membrane rupture (AOR = 9.30; 95% CI = 3.18–27.16), and hypertension during pregnancy (AOR = 4.40; 95% CI = 1.18–16.42) were identified as independent risk factors for preterm birth.ConclusionPreterm birth remains a significant public health issue in Rwanda. The associated risk factors for preterm birth were advanced maternal age, secondhand smoke, hypertension, history of abortion, and preterm membrane rupture. This study therefore recommends routine antenatal screening to identify and closely follow-up of those high-risk groups, in order to avoid the short- and long-term effects of preterm birth.

Immunological disease activity parameters at conception are risk factors for preterm birth and low birth weight in patients with systemic lupus erythematosus.

This study aimed to identify which disease activity parameters may be risk factors for preterm birth (PB) and low birth weight (LBW) in patients with systemic lupus erythematosus (SLE). We also analyzed the extent to which these parameters affected PB and LBW. We collected the SLE Disease Activity Index (SLEDAI), the rate of lupus low disease activity state (LLDAS) attainment, complement levels, and the titer of anti-double stranded DNA (dsDNA) antibody as disease activity parameters. We retrospectively analyzed the associations of these parameters with PB and LBW. Sixty pregnancies were included in this study. C3 levels and anti-dsDNA antibody titers at conception were strongly associated with PB (p = 0.03 and p = 0.01, respectively), whereas C3 and CH50 levels were associated with LBW (p = 0.02 and p = 0.03, respectively). A logistic regression analysis showed that the cutoff values of C3 and anti-dsDNA antibody for PB were 62.0mg/dl and 5.4IU/ml, respectively. The cutoff values of C3 and CH50 for LBW were 87.0mg/dl and 41.8U/ml, respectively. The risk of PB or LBW was increased when divided by the cutoff value, and the combination of these cutoff values showed a significantly higher risk of PB and LBW (p = 0.01 and p < 0.01, respectively). PB and LBW are strongly associated with disease activity parameters in patients with SLE. Therefore, strictly monitoring and controlling these disease activity parameters, with or without clinical manifestation, is important for women who want to become mothers.

Identification of biochemical biomarkers associated with premature cervical shortening in high-risk, asymptomatic pregnant women: a retrospective data analysis

Reliably predicting spontaneous preterm birth remains challenging, therefore it persists as a major contributor to perinatal morbidity and mortality. The use of biomarkers to predict premature cervical shortening, a recognised risk factor for spontaneous preterm birth, is yet to be fully explored in current literature. This study evaluates seven cervicovaginal biochemical biomarkers as possible predictors of premature cervical shortening. Asymptomatic, high-risk women (n = 131) presenting to a specialised preterm birth prevention clinic were analysed through a retrospective data analysis. Cervicovaginal biochemical biomarker concentrations were obtained, and the shortest cervical length measurement, up to 28 weeks’ gestation, was recorded. Associations between biomarker concentration and cervical length were then analysed. Of the seven biochemical biomarkers, Interleukin-1 Receptor Antagonist and Extracellular Matrix Protein-1 had statistically significant relationships with cervical shortening below 25 mm. Further investigation is required to validate these findings and any downstream clinical utility, with intentions to improve perinatal outcomes. IMPACT STATEMENT What is already known on this subject? Preterm birth is a major cause of perinatal morbidity and mortality. A woman’s risk of delivering preterm is currently stratified using historical risk factors, mid-gestation cervical length, and biochemical biomarkers such as foetal fibronectin. What do the results of this study add? In a cohort of high-risk, asymptomatic pregnant women, two cervicovaginal biochemical biomarkers, Interleukin-1 Receptor Antagonist and Extracellular Matrix Protein-1, displayed associations with premature cervical shortening. What are the implications of these findings for clinical practice and/or further research? Further investigation into the possible clinical utility of these biochemical biomarkers is warranted, with a view to improving preterm birth prediction and antenatal resource utilisation, thereby reducing the burden of preterm birth and its sequelae in a cost-effective manner.

Nomogram for predicting the risk of preterm birth in women undergoing in vitro fertilization cycles

BackgroundThe aim of this study was to develop a nomogram for predicting the risk of preterm birth in women undergoing in vitro fertilization (IVF) cycles.MethodsA retrospective study of 4266 live birth cycles collected from January 2016 to October 2021 at the Center for Reproductive Medicine, First Hospital of Jilin University was performed. The sample size was sufficient based on the minimal ten events per variable (EPV) rule. The primary outcome of this study was preterm birth. The cycles were divided into the preterm birth group (n = 827) and the full-term delivery group (n = 3439). A nomogram was established based on the multivariate logistic regression analysis results. The area under the curve (AUC) was calculated to assess the prediction accuracy of the nomogram model. The calibration curve was used to measure the calibration of the nomogram.ResultsMultivariate logistic regression analyses showed that female obesity or overweight (OR = 1.366, 95% CI: 1.111–1.679; OR = 1.537, 95% CI: 1.030–2.292), antral follicle count (AFC) of more than 24 (OR = 1.378, 95% CI: 1.035–1.836), multiple pregnancies (OR = 6.748, 95% CI: 5.559–8.190), gestational hypertension (OR = 9.662, 95% CI: 6.632–14.078) and gestational diabetes (OR = 4.650, 95% CI: 2.289–9.445) were the independent risk factors for preterm birth in IVF patients. The area under curve (AUC) under the receiver operating characteristic (ROC) curve in the prediction model was 0.781(95%CI: 0.763–0.799). The calibration curve of the nomogram showed that the prediction model had a good calibration.ConclusionsWe used five risk factors to conduct a nomogram to predict preterm birth rates for patients undergoing IVF cycles. This nomogram can provide a visual assessment of the risk of preterm birth for clinical consultation.

Vitamin D deficiency in pregnancy and the risk of preterm birth: a nested case–control study

BackgroundEach year, an estimated 15 million babies are born preterm. Micronutrient deficiencies, including vitamin D deficiency (VDD), are common in many low- and middle-income countries (LMICs), and these conditions are often associated with adverse pregnancy outcomes. Bangladesh experiences a high prevalence of VDD. The country also has a high preterm birth (PTB) rate. Using data from a population-based pregnancy cohort, we estimated the burden of VDD during pregnancy and its association with PTB.MethodsPregnant women (N = 3,000) were enrolled after ultrasound confirmation of gestational age at 8–19 weeks of gestation. Trained health workers prospectively collected phenotypic and epidemiological data at scheduled home visits. Trained phlebotomists collected maternal blood samples at enrollment and 24 -28 weeks of gestation. Aliquots of serum were stored at -800 C. We conducted a nested case–control study with all PTB (n = 262) and a random sample of term births (n = 668). The outcome, PTB, was defined as live births < 37 weeks of gestation, based on ultrasound. The main exposure was vitamin D concentrations of 24–28 weeks maternal blood samples. The analysis was adjusted for other PTB risk factors. Women were categorized as VDD (lowest quartile of 25(OH)D; < = 30.25 nmol/L) or not deficient (upper-three quartiles of 25(OH)D; > 30.25 nmol/L). We used logistic regression to determine the association of VDD with PTB, adjusting for potential confounders.ResultsThe median and interquartile range of serum 25(OH)D was 38.0 nmol/L; 30.18 to 48.52 (nmol/L). After adjusting for co-variates, VDD was significantly associated with PTB [adjusted odds ratio (aOR) = 1.53, 95% confidence interval (CI) = 1.10 – 2.12]. The risk of PTB was also higher among women who were shorter (aOR = 1.81, 95% CI: 1.27–2.57), primiparous (aOR = 1.55, 95% CI = 1.12 – 2.12), passive smokers (aOR = 1.60, 95% CI = 1.09 – 2.34), and those who received iron supplementation during pregnancy (aOR = 1.66, 95% CI: 1.17, 2.37).ConclusionVDD is common in Bangladeshi pregnant women and is associated with an increased risk of PTB.