Higher Risk Of Preterm Birth Research Articles

Medically Assisted Reproduction Treatment Types and Birth Outcomes: A Between-Family and Within-Family Analysis.

To compare risks of adverse birth outcomes among pregnancies conceived with and without medically assisted reproduction treatments. Birth certificates were used to study birth outcomes of all neonates born in Utah from 2009 through 2017. Of the 469,919 deliveries, 52.8% (N=248,013) were included in the sample, with 5.2% of the neonates conceived through medically assisted reproduction. The outcome measures included birth weight, gestational age, low birth weight (LBW, less than 2,500 g), preterm birth (less than 37 weeks of gestation), and small for gestational age (SGA, birth weight less than the 10th percentile). Linear models were estimated for the continuous outcomes (birth weight, gestational age), and linear probability models were used for the binary outcomes (LBW, preterm birth, SGA). First, we compared the birth outcomes of neonates born after medically assisted reproduction and natural conception in the overall sample (between-family analyses), before and after adjustment for parental background and neonatal characteristics. Second, we employed family fixed effect models to investigate whether the birth outcomes of neonates conceived through medically assisted reproduction differed from those of their naturally conceived siblings (within-family comparisons). Neonates conceived through medically assisted reproduction weighed less, were born earlier, and were more likely to be LBW, preterm, and SGA than neonates conceived naturally. More invasive treatments (assisted reproductive technology [ART] and artificial insemination [AI] or intrauterine insemination) were associated with worse birth outcomes; for example, the proportion of LBW and preterm birth was 6.1% and 7.9% among neonates conceived naturally and 25.5% and 29.8% among neonates conceived through ART, respectively. After adjustments for various neonatal and parental characteristics, the differences in birth outcomes between neonates conceived through medically assisted reproduction and naturally were attenuated yet remained statistically significant; for example, neonates conceived through ART were at 3.2 percentage points higher risk for LBW (95% CI 2.4-4.1) and 4.8 percentage points higher risk for preterm birth (95% CI 3.9-5.7). Among siblings, the differences in the frequency of adverse outcomes between neonates conceived through medically assisted reproduction and neonates conceived naturally were small and statistically insignificant for all types of treatments. Medically assisted reproduction treatments are associated with adverse birth outcomes; however, those risks are unlikely to be associated with the infertility treatments itself.

Maternal and fetal mortality in adolescent patients

Adolescent pregnancy represents a major health problem worldwide, because it is associated with multiple maternal and fetal complications, the most important one being maternal death. According to the specialty literature, the leading cause of death among adolescents is represented by adverse outcomes associated with pregnancy. Also, in this group of patients there is a high risk of sexually trans­mit­ted diseases. The most common obstetrical com­pli­ca­tions in pregnant adolescents are preeclampsia and eclam­p­sia, which increase the risk of maternal and fetal mor­ta­li­ty. Re­gar­ding the neonatal outcomes, it has been de­mon­stra­ted that newborns from adolescent patients have a higher risk of preterm birth, low birth weight and stillbirth. All these com­pli­ca­tions may be due to the physical and biological im­ma­tu­rity, but also may be the result of the lack of antenatal care. We performed a retrospective study in the Department of Obstetrics and Gynecology of the University Emergency Hos­pi­tal Bucharest between 30 September 2020 and 30 Sep­tem­ber 2022. The study included three adolescents who gave birth and were declared dead in our unit, and a control group of five adult patients with the same characteristics. The aim of the study was to establish the incidence and the risk factors of mortality among adolescents compared to adult women. The neonatal status was established by neonatology team. The results showed that the incidence of maternal mortality is higher in adolescent patients com­pared to the adult ones as reported to all patients who gave birth. The patients aged between 35 and 40 years old had the highest rate of mortality, followed by the group of patients aged between 18 and 19 years. The lack of antenatal care had an important significance in both groups. Fetal mortality was similar in both adolescent and adult groups.

ОСОБЛИВОСТІ ПЕРЕБІГУ ВАГІТНОСТІ ТА РОЗРОДЖЕННЯ ЖІНОК З ЕКСТРАКОРПОРАЛЬНИМ ЗАПЛІДНЕННЯМ З ГРУПИ ВИСОКОГО РИЗИКУ ПО ВИНИКНЕННЮ ПЕРЕДЧАСНИХ ПОЛОГІВ

The article is a part of the research project at the Department of Obstetrics and Gynecology No.2 of Higher Education Institution Poltava State Medical University "The role of chronic infection of the uterus and lower genital tract in the formation of obstetric and gynecological pathology" (state registration No. 0117U005276, implementation period 2017-2022). In modern reproductive medicine, infertility in marriage is considered a problem of particular importance. That is why modern assisted reproductive technologies are chosen as a method of treatment for many married couples, and their increased application necessitates intensive monitoring of the course of pregnancy and delivery. Pregnant women after in vitro fertilization programs are at high risk of miscarriage and preterm birth. The aim of the research was to study the features of pregnancy, childbirth and the condition of newborns in women after in vitro fertilization, which are classified as high risk for preterm birth. Women were included in the study at 18-20 weeks 6 days of pregnancy. We examined 85 women who became pregnant after in vitro fertilization (study group A: 37 pregnant women who refused preventive treatment and received medications in accordance with regulations; study group B: 48 pregnant women who have received the proposed treatment since their inclusion in the study. The control group included 20 apparently healthy pregnant women with its natural pregnancy onset. In pregnant women of study group A, pregnancies ended in premature birth by 1.7 times more often, and most of them occurred before 34 weeks; during pregnancy, there was a greater risk of preterm birth, which required enhanced correction in addition to conservative measures: suturing the cervix and the use of obstetric unloading pessary; the frequency of delivery by cesarean section prevailed by 1.3 times. Moreover, only in this group, pathological bleeding was observed, surgery was performed and perinatal mortality was recorded. Pregnant women who agreed to preventive treatment developed fewer preterm births after 34 weeks. Complications of pregnancy and childbirth were much less common in these women. Surgical intervention in childbirth and the frequency of delivery by cesarean section were also much less common.

Effect of preoperative lower-normal cervical length on perinatal outcomes after laparotomy-assisted fetoscopic spina bifida repair

Patients with a short cervical length ( < 25mm) are excluded for in utero spina bifida repair, given their expected higher risk for preterm birth. We hypothesized that patients with a preoperative cervical length in the lower-normal range are at higher risk for adverse perinatal outcomes.

Ureaplasma and Mycoplasma screening in women at high risk for preterm birth

To examine the association of positive Ureaplasma and Mycoplasma (U & M) with preterm birth and the rates of recurrence in a high-risk pregnant population. This was a retrospective study of all pregnant women who had U & M cervical culture at a tertiary care center. At our institution, it is our protocol to perform U & M cervical culture for women with high risk factors of preterm birth (history of preterm birth, recurrent pregnancy loss, multiple gestation, and cerclage) and treat women and partners. Test-of-cure is performed after the treatment. We examined rates of recurrence after the treatment. For the analysis of preterm birth (less than 37 weeks), we limited analyses to women who had cervical culture at less than 16 weeks, singleton gestation, and the indication for culture being a history of preterm birth or recurrent pregnancy loss. Adjusted odds ratios (aOR) with 95% confidence interval (95%CI) were calculated, controlling confounders. Of 510 women, 311 (61%) and 95 (19%) had Ureaplasma and Mycoplasma, respectively. Of 178 who had Ureaplasma treated and had test-of cure, 137 (77%) had recurrence. Of 41 who had Mycoplasma treated and had test-of-cure, 10 (24%) had recurrence. There was no difference in preterm birth between women who had negative Ureaplasma, those who had Ureaplasma and treated, and those who had Ureaplasma but were not treated (38% vs. 33% [aOR 0.81; 95%CI 0.43-1.54]) vs. 54% [aOR 1.91; 95%CI 0.58-6.27], respectively). Similarly, there was no difference in preterm birth between women who had negative Mycoplasma, those who had Mycoplasma and treated, and those who had Mycoplasma but were not treated (38% vs. 27% [aOR 0.64; 95%CI 0.24-1.75] vs. 40% [aOR 1.05; 95%CI 0.28-3.91], respectively). Ureaplasma is prevalent and the recurrence rate after treatment is high. Women who had positive Ureaplasma or Mycoplasma and were treated did not have increased odds of preterm birth compared to those who did not have Ureaplasma or Mycoplasma. Our findings question the clinical utility of screening for U & M in pregnancies at high risk for preterm birth.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Association between paternal age and subtypes of preterm birth: a retrospective study

Research questionIs advanced paternal age (APA) associated with preterm birth overall and with the subtypes of preterm birth? DesignA total of 66,167 pregnancies were included. Linear regression and logistic regression models were used to analyse the association between paternal age and subtypes of preterm birth. ResultsAPA was associated with a higher risk of preterm birth (35–44 years: odds ratio [OR] 1.16 [1.04–1.28], P = 0.006; >44 years: OR 1.40 [1.10–1.78], P = 0.007) and very early preterm birth (VPTB; <34 weeks) (35–44 years: OR 1.46 [1.17–1.81], P = 0.002; >44 years: OR 1.65 [1.01–2.69], P = 0.045). The increased risk of preterm birth was mostly associated with preterm birth with premature rupture of membranes (PROM-PTB) (35–44 years: OR 1.23 [1.03–1.48], P = 0.021) and medically induced preterm birth (MI-PTB) (>44 years: OR 1.55 [1.12–2.15], P = 0.008). For women who carried a male fetus, having the father in the 35- to 44-year-old group carried a 1.29-fold risk of PROM-PTB (OR 1.29 [1.02–1.63], P = 0.031) and a 1.26-fold risk of MI-PTB (OR 1.26 [1.04–1.52], P = 0.017). There was no evidence of a higher risk of PROM-PTB among women carrying a female fetus, but there was a 1.67-fold higher risk of MI-PTB for the 45-or-older paternal age group (OR 1.67 [1.04–2.67], P = 0.035). ConclusionsThese results suggest that APA is associated with a higher risk of preterm birth and VPTB, mainly related to PROM-PTB and MI-PTB. The study also indicates a fetal sex-specific association between APA and a higher risk of PROM-PTB for male fetuses.

Risk of Adverse Maternal Outcomes in Pregnant Women With Disabilities

Women with disabilities have a higher risk of preterm birth, gestational diabetes, preeclampsia, and cesarean delivery; however, their risk of other obstetric interventions, adverse maternal outcomes, and clinical indications for increased cesarean delivery is unclear. To evaluate risk of a range of obstetric interventions and adverse maternal outcomes, including severe maternal morbidities (SMM) and mortality, among women with and without disabilities. The Consortium on Safe Labor was a retrospective cohort that included comprehensive medical chart review for deliveries between January 2002 and January 2008. Data were collected from 12 clinical sites, which included 19 hospitals across the United States. This secondary analysis was conducted in February to July 2021. Using International Classification of Diseases, Ninth Revision, codes and a validated algorithm to define disability, participants were classified as having physical, intellectual, sensory, or any disability, and compared with women with no documented disability. The relative risk (RR) of 23 obstetric interventions and adverse maternal outcomes, including SMM and mortality, was evaluated. Of the 223 385 women in the study, 9206 (4.1%) were Asian or Pacific Islander, 50 235 (22.5%) were Black, 39 039 (17.5%) were Hispanic, and 110 443 (49.4%) were White, with a mean (SD) age of 27.6 (6.2) years. There were 2074 (0.9%) women with disability and 221 311 (99.1%) without. Among women with disabilities, 1733 (83.5%) were physical, 91 (4.4%) were intellectual, and 250 (12.1%) were sensory. Compared with women with no disability, women with disabilities had higher risk of gestational diabetes, placenta previa, premature rupture of membranes, preterm premature rupture of membranes, and postpartum fever as well as maternal death (adjusted relative risk [aRR], 11.19; 95% CI, 2.40-52.19) and individual SMMs: severe preeclampsia/eclampsia (aRR, 2.15; 95% CI, 1.80-2.56), hemorrhage (aRR, 1.27; 95% CI, 1.09-1.49), and fever (aRR, 1.32; 95% CI, 1.03-1.67), with the highest risk observed for thromboembolism (aRR, 6.08; 95% CI, 4.03-9.16), cardiovascular events (aRR, 4.02; 95% CI, 2.87-5.63), and infection (aRR, 2.69; 95% CI, 1.97-3.67). Women with any disability also had higher risk of interventions, including oxytocin augmentation, operative vaginal delivery, and cesarean delivery (aRR, 1.33; 95% CI, 1.25-1.42), with the cesarean indication less likely to be medically indicated (aRR, 0.79; 95% CI, 0.70-0.89). Risk of adverse outcomes and interventions remained consistent across disability categories. In this study, women with physical, intellectual, and sensory disability during pregnancy were at higher risk of adverse outcomes, including a broad range of SMM and maternal mortality.

Perinatal outcomes in women with sickle cell disease: a matched cohort study from London, UK.

There are limited data on contemporary outcomes for women with sickle cell disease (SCD) in pregnancy. We conducted a single-site matched cohort study, comparing 131 pregnancies to women with SCD between 2007 and 2017 to a comparison group of 1310 pregnancies unaffected by SCD. Restricting our analysis to singleton pregnancies that reached 24 weeks of gestation, we used conditional Poisson regression to estimate adjusted risk ratios (aRRs) for perinatal outcomes. Infants born to mothers with SCD were more likely to be small for gestational age [aRR 1·69, 95% confidence interval (CI) 1·13-2·48], preterm (aRR 2·62, 95% CI 1·82-3·78) and require Neonatal Unit (NNU) admission (aRR 3·59, 95% CI 2·18-5·90). Pregnant women with SCD were at higher risk of pre-eclampsia/eclampsia (aRR 3·53, 95% CI 2·00-6·24), more likely to receive induction of labour (aRR 2·50, 95% CI 1·82-1·76) and caesarean birth (aRR 1·44, 95% CI 1·18-1·76). In analysis stratified by genotype, the risk of adverse outcomes was highest in haemoglobin SS (HbSS) pregnancies (n = 80). There was no strong evidence that haemoglobin SC (HbSC) pregnancies (n = 46) were at higher risk of preterm birth, caesarean delivery, or NNU admission. Pre-eclampsia/eclampsia was more frequently observed in HbSC pregnancies. Despite improvements in the care of pregnant women with SCD, the increased risk of adverse perinatal outcomes remains.

Association between maximum temperature and PM2.5 with pregnancy outcomes in Lima, Peru.

Background:We have previously documented an inverse relationship between PM2.5 in Lima, Peru, and reproductive outcomes. Here, we investigate the effect of temperature on birth weight, birth weight-Z-score adjusted for gestational age, low birth weight, and preterm birth. We also explore interactions between PM2.5 and temperature.Methods:We studied 123,034 singleton births in three public hospitals of Lima with temperature and PM2.5 during gestation between 2012 and 2016. We used linear, logistic, and Cox regression to estimate associations between temperature during gestation and birth outcomes and explored possible modification of the temperature effect by PM2.5.Results:Exposure to maximum temperature in the last trimester was inversely associated with both birth weight [β: −23.7; 95% confidence interval [CI]: −28.0, −19.5] and z-score weight-for-gestational-age (β: −0.024; 95% CI: −0.029, −0.020) with an interquartile range of 5.32 °C. There was also an increased risk of preterm birth with higher temperature (interquartile range) in the first trimester (hazard ratio: 1.04; 95% CI: 1.001, 1.070). The effect of temperature on birthweight was primarily seen at higher PM2.5 levels. There were no statistically significant associations between temperature exposure with low birth weight.Conclusions:Exposition to maximum temperature was associated with lower birth weight and z-score weight-for-gestational-age and higher risk of preterm birth, in accordance with much of the literature. The effects on birth weight were seen only in the third trimester.

Birth outcomes among women with congenital neuromuscular disabilities

BackgroundWomen with disabilities are at an increased risk for adverse birth outcomes; however, research among women with congenital neuromuscular disabilities (cNMD) is limited. ObjectiveTo describe characteristics and compare birth outcomes among women with and without cNMD. MethodsData were from the Slone Birth Defects Study (case-control, conducted from 1976 to 2015), which collected information on demographic, reproductive, and lifestyle characteristics. cNMD included spina bifida, cerebral palsy, muscular dystrophy, contractures, or arthrogryposis and were identified by participant report. Those with cNMD were matched to participants without cNMD by interview year and study site. We use modified Poisson regression to estimate relative risks (RR) for low birthweight, macrosomia, preterm birth, and small/large-for-gestational age (SGA/LGA). Given the case-control design and overrepresentation of infants with congenital anomalies, data were weighted to reflect a 3% national prevalence of infants with congenital anomalies. ResultsWomen with cNMD (n = 125) were more likely to be white, nulliparous, have a cesarean section, have an unplanned pregnancy, report a pre-pregnancy BMI ≥25 kg/m2, smoke during pregnancy, and report genitourinary infections. Women with cNMD had infants with shorter gestational length (mean difference: −7.44 days, 95% CI: −13.94, −0.95) compared to women without cNMD. cNMD was associated with higher risk of preterm birth (RR = 3.98, 95% CI: 1.33, 11.95) and SGA (RR = 2.14, 95% CI: 0.74, 6.15). ConclusionWomen with cNMD were more likely to deliver preterm and have an SGA infant. These findings highlight disparities faced by women with cNMD and stress the need to provide optimal perinatal and reproductive care.

Vaginal Microbiota, Genital Inflammation and Extracellular Matrix Remodelling Collagenase: MMP-9 in Pregnant Women With HIV, a Potential Preterm Birth Mechanism Warranting Further Exploration.

BackgroundPregnant women living with HIV infection (PWLWH) have elevated rates of preterm birth (PTB) in which HIV and cART are implicated. PWLWH also have a high prevalence of adverse vaginal microbiota, which associate with genital tract inflammation. The mechanism underlying PTB in PWLWH is unknown. We present the first data in PWLWH on genital-tract matrix-metalloproteinase-9(MMP-9), an important collagenase implicated in labour onset, and tissue inhibitor of metalloproteinases-1(TIMP-1) and explore correlations with local inflammation and vaginal bacteria.Material and MethodsCervical vaginal fluid (CVF) collected by a soft cup and high vaginal swabs (HVS) were obtained from PWLWH and HIV uninfected pregnant women (HUPW) at three antenatal time points. Maternal characteristics, combination antiretroviral therapy (cART) exposure, and pregnancy outcome were recorded. Concentrations of MMP-9, TIMP-1 and ten cytokines were measured by immunoassays. Vaginal microbiota composition was determined through 16S rRNA amplicon sequencing. MMP-9, TIMP-1 and cytokine concentrations were compared by HIV status, cART, and prematurity and in PWLWH correlations with polymorphonuclear leucocytes, cytokines and bacterial genera were explored.ResultsCVF was available for 50 PWLWH (108 samples) and 12 HUPW (20 samples) between gestation weeks 14-38. Thirty-six PWLWH conceived on cART and 14 initiated post-conception. There were five and one PTB outcomes in PWLWH and HUPW respectively. PWLWH had higher mean CVF concentrations of MMP-9 (p<0.001) and TIMP-1 (p=0.035) in the second trimester compared with HUPW with a similar trend in the third trimester. PWLWH also had higher CVF values of cytokines: IL-1β, IL-8, IL-12 and TNF-α in both trimesters compared to HUPW (p ≤ 0.003). In PWLWH, MMP-9 positively correlated with TIMP-1 (r=0.31, p=0.002) and CVF polymorphonuclear leucocytes (r=0.57, p=0.02). Correlations were observed between MMP-9 and three cytokines: IL-1β (r=0.61), IL-8 (r=0.57) and TNF-α (r=0.64), p<0.001, similarly for TIMP-1. Abundance of anaerobic pathobionts correlated with MMP-9: Gardnerella (r=0.44, p<0.001), Atopobium (r=0.33, p=0.005), and Prevotella genera (r=0.39, p<0.001). Conversely proportion of Lactobacillus genera negatively correlated with MMP-9 (rho=-0.46, p<0.001). MMP-9/TIMP-1 ratio increased with gestational age at sampling in PWLWH, but this was no longer significant after adjusting for confounders and no difference by prematurity was observed in this sub-study.ConclusionsHere we show strong correlations of MMP-9 to genital tract inflammation and sub-optimal bacterial genera in PWLWH indicating the ascending genital tract infection pathway may be a contributory mechanism to the high risk of PTB.

Blastocyst development rate influences singleton gestational age of similarly graded blastocysts after vitrified–warmed single embryo transfer cycles

Research questionDoes the development rate of blastocysts influence neonatal outcomes after blastocyst transfer cycles when the morphological score of the transferred blastocysts is similar? DesignA retrospective study involving singleton live births born to 1280 women undergoing single frozen blastocyst transfers (FBTs) between January 2016 and December 2018 at a tertiary care centre. Patients were grouped into day-5 or day-6 groups depending on the development rate of blastocysts. These were further grouped into four groups based on the blastocyst inner cell mass and trophectoderm scoring: excellent (AA); good (AB or BA); average (AC, CA or BB); and poor (BC or CB). The primary outcomes were gestational age and singleton birth weight. ResultsSingletons resulting from day-5 single FBT were at a lower risk of preterm birth than those resulting from day-6 single FBT (adjusted OR 0.63, 95% CI 0.41 to 0.97, P = 0.035). In the day-5 good-quality blastocyst group and day-5 average-quality blastocyst group, singletons were at a lower risk of preterm birth than those resulting from day-6 groups, respectively (adjusted OR 0.22, 95% CI 0.08 to 0.63, P = 0.005 and adjusted OR 0.52, 95% CI 0.29 to 0.94, P = 0.03). ConclusionsDay-6 single FBT was associated with a higher risk of preterm birth compared with day-5 single FBT in good and average morphological scoring blastocysts. Our analysis was restricted to women with singleton births from single FBTs. Future prospective studies are required to confirm the findings.

Associations between prenatal multiple metal exposure and preterm birth: Comparison of four statistical models

BackgroundExposure to some heavy metals has been demonstrated to be related to the risk of preterm birth (PTB). However, the effects of multi-metal mixture are seldom assessed. Thus, we aimed to investigate the associations of maternal exposure to metal mixture with PTB, and to identify the main contributors to PTB from the mixture. MethodsThe population in the nested case-control study was from a prospective cohort enrolled in Wuhan, China between 2012 and 2014. Eighteen metals were measured in maternal urine collected before delivery. Logistic regression, elastic net regularization (ENET), weighted quantile sum regression (WQSR), and Bayesian kernel machine regression (BKMR) were used to estimate the overall effect and identify important mixture components that drive the associations with PTB. ResultsLogistic regression found naturally log-transformed concentrations of 13 metals were positively associated with PTB after adjusting for the covariates, and only V, Zn, and Cr remained the significantly positive associations when additionally adjusting for the 13 metals together. ENET identified 11 important metals for PTB, and V (β = 0.23) had the strongest association. WQSR determined the positive combined effect of metal mixture on PTB (OR: 1.44, 95%CI: 1.32, 1.57), and selected Cr and V (weighted 0.41 and 0.32, respectively) as the most weighted metals. BKMR analysis confirmed the overall mixture was positively associated with PTB, and the independent effect of V was the most significant. Besides, BKMR showed the non-linear relationships of V and Cu with PTB, and the potential interaction between Zn and Cu. ConclusionApplying different statistical models, the study found that exposure to the metal mixture was associated with a higher risk of PTB, and V was identified as the most important risk factor among co-exposed metals for PTB.

Residential particulate matter, proximity to major roads, traffic density and traffic volume as risk factors for preterm birth in California.

While pollution from vehicle sources is an established risk factor for preterm birth, it is unclear whether distance of residence to the nearest major road or related measures like major road density represent useful measures for characterising risk. To determine whether major road proximity measures (including distance to major road, major road density and traffic volume) are more useful risk factors for preterm birth than other established vehicle-related measures (including particulate matter <2.5μm in diameter (PM2.5 ) and diesel particulate matter (diesel PM)). This retrospective cohort study included 2.7 million births across the state of California from 2011-2017; each address at delivery was geocoded. Geocoding was used to calculate distance to the nearest major road, major road density within a 500m radius and major road density weighted by truck volume. We measured associations with preterm birth using risk ratios adjusted for target demographic, clinical, socioeconomic and environmental covariates (aRRs). We compared these to the associations between preterm birth and PM2.5 and diesel PM by census tract of residence. Findings showed that whereas higher mean levels of PM2.5 and diesel PM by census tract were associated with a higher risk of preterm birth, living closer to roads or living in higher traffic density areas was not associated with higher risk. Residence in a census tract with a mean PM2.5 in the top quartile compared with the lowest quartile was associated with the highest observed risk of preterm birth (aRR 1.04, 95% CI 1.04, 1.05). Over a large geographical region with a diverse population, PM2.5 and diesel PM were associated with preterm birth, while measures of distance to major road were not, suggesting that these distance measures do not serve as a proxy for measures of particulate matter in the context of preterm birth.

CHANGES IN THE ACTIVITY OF INDUCIBLE NO-SYNTHASE AND ARGINASE, THEIR RELATIONSHIP WITH THE LEVEL OF PRO- AND ANTI-INFLAMMATORY CYTOKINES IN CERVICAL MUCUS IN PREGNANT WOMEN, WHO UNDERWENT IVF AND ARE AT RISK OF PRETERM CHILDBIRTH

Introduction. Nitric oxide (NO) produces a wide range of bioregulatory effects. Imbalance in the ratio of the activity of inducible NO-synthase and arginase in favor of iNOS can lead to a pro-inflammatory reaction. At the risk of preterm childbirth, the content of proinflammatory cytokines increases both at the local and systemic levels. The aim of this work is to study the relationship between changes in the content of pro- and anti-inflammatory cytokines and the activity of inducible NO-synthase and arginase in the cervical mucus of women with in vitro fertilization (IVF), who are at risk of preterm childbirth. Materials and methods. The test group (TG) included 37 women, who underwent IVF and presented prognostic signs, indicating a high risk of preterm birth in the future. The control group (CP) consisted of 20 healthy pregnant women, who did not undergo assisted reproductive technologies. We determined the indicators of inducible NO-synthase activity and total arginase activity, as well as the level of pro- and anti-inflammatory cytokines in the mucus of the cervical canal of the participants at their 28-34 weeks of pregnancy. Results and discussion. The activity of iNOS in TG significantly increased (in 2.57 times) compared to healthy pregnant women (CP), while the activity of arginase, on the contrary, decreased significantly (in 1.91 times). There was a significant increase in the levels of pro-inflammatory cytokines INF-γ and TNF-α in the TG women, while they demonstrated the significantly reduced concentration of anti-inflammatory cytokine IL-10. In cervical mucus taken from TG women, positive correlations were found between an increase in the concentration of the proinflammatory cytokine INF-γ and an increase in iNOS activity, between a decrease in IL-10 levels and arginase activity, and a negative relationship between an increase in iNOS activity and a decrease in arginase activity. Conclusions. The detected cytokine imbalance in pregnant women, who underwent in vitro fertilization and were at risk of preterm childbirth, together with a impaired ratio of iNOS and arginase, indicates an inappropriate level of immunosuppression. These immune changes, by activating cellular responses of maternal immunity, can contribute to preterme childbirth.

Change in cervical length after arrested preterm labor and risk of preterm birth

ABSTRACTObjectiveTo assess the association between preterm birth and cervical length after arrested preterm labor in high‐risk pregnant women.MethodsIn this post‐hoc analysis of a randomized clinical trial, transvaginal cervical length was measured in women whose contractions had ceased 48 h after admission for threatened preterm labor. At admission, women were defined as having a high risk of preterm birth based on a cervical length of < 15 mm or a cervical length of 15–30 mm with a positive fetal fibronectin test. Logistic regression analysis was used to investigate the association of cervical length measured at least 48 h after admission and of the change in cervical length between admission and at least 48 h later, with preterm birth before 34 weeks' gestation and delivery within 7 days after admission.ResultsA total of 164 women were included in the analysis. Women whose cervical length increased between admission for threatened preterm labor and 48 h later (32%; n = 53) were found to have a lower risk of preterm birth before 34 weeks compared with women whose cervical length did not change (adjusted odds ratio (aOR), 0.24 (95% CI, 0.09–0.69)). The risk in women with a decrease in cervical length between the two timepoints was not different from that in women with no change in cervical length (aOR, 1.45 (95% CI, 0.62–3.41)). Moreover, greater absolute cervical length after 48 h was associated with a lower risk of preterm birth before 34 weeks (aOR, 0.90 (95% CI, 0.84–0.96)) and delivery within 7 days after admission (aOR, 0.91 (95% CI, 0.82–1.02)). Sensitivity analysis in women randomized to receive no intervention showed comparable results.ConclusionOur study suggests that the risk of preterm birth before 34 weeks is lower in women whose cervical length increases between admission for threatened preterm labor and at least 48 h later when contractions had ceased compared with women in whom cervical length does not change or decreases. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Association between sleep duration during pregnancy and preterm birth: a dose-response meta-analysis

Objective Preterm birth is now a global health problem. There is a great alteration of sleep duration in pregnancy. Whether sleep duration in pregnancy affects preterm birth remains unclarified. This study aimed to examine the associations of sleep duration on preterm birth risk based on the dose–response meta-analysis. Materials and methods Electronic databases (PubMed, Web of Science, and Ovid) were searched for relevant studies from database inception to September 2020. Studies describing the associations of maternal sleep duration with preterm birth risk were included. A random-effects model was adopted to calculate the summarized relative risk (SRR) and 95% confidence intervals (CIs) as the effect sizes for all studies. Moreover, dose–response analysis was used for combining studies that used categories of sleep duration as exposure. In addition, subgroup analysis and meta-regression analysis were conducted to adjust potential confounders and investigate the source of heterogeneity. Results A total of 3771 unique studies were screened, and eight cohort studies and one case-control study were identified, with a total of 2000 preterm birth cases. Pooled data indicated that extreme sleep duration (short sleep duration or long sleep duration) in pregnancy was closely related to preterm birth in comparison with normal sleep duration (SRR = 1.13, 95%CI: 1.05–1.22) and there was no significant heterogeneity among studies (I 2 = 7.0%, p = .37). Begg’s funnel plot failed to uncover any evidence of publication bias. The non-linearity in the association of sleep duration with preterm birth showed significance (p < .01). Considering pregnant women slept for 7 h as a reference, 4 h short sleepers had a higher predicted risk of preterm birth (RR = 1.10, 95%CI: 1.01–1.19). Additionally, as compared with women with normal sleep duration, the preterm birth risk with short sleep durations (SRR = 1.20, 95%CI: 1.05–1.37) was elevated among pregnant women, and long sleep duration was related to preterm birth after adjusting for age (SRR = 1.20, 95%CI: 1.01–1.42). Conclusion There is an association of extreme sleep duration in pregnancy with preterm birth. In a non-linear dose-response meta-analysis, a U-shaped relationship between sleep duration and risk of preterm birth was observed and pregnant women who slept 4 h/day had a significantly higher risk of preterm birth than those who slept normally.

The risk of preterm birth in combinations of socioeconomic position and mental health conditions in different age groups: a Danish nationwide register-based cohort study

BackgroundInequality in preterm birth is a world-wide challenge that has proved difficult for maternity care services to meet. Reducing the inequality requires identification of pregnant women at particularly high risk of preterm birth in order to target interventions. Therefore, the aim was to estimate the risk of preterm birth in women with different combinations of socioeconomic position, mental health conditions, and age.MethodsIn this nationwide register-based cohort study, we included all first-time mothers that gave birth to a singleton liveborn infant in Denmark between 2000 and 2016. The absolute and relative risk of preterm birth (< 37 weeks of gestation) was examined in different combinations of educational level (high, intermediate, and low) and mental health conditions (no, minor, and moderate/severe) in three age strata (≤23, 24–30, and ≥ 31 years). We estimated the relative risk using Poisson regression with a robust error variance. As additive interaction can help identify subgroups where limited resources can be of best use, we measured the attributable proportion to assess the risk that is due to interaction of the different exposures.ResultsOf the 415,523 included first-time mothers, 6.3% gave birth prematurely. The risk of preterm birth increased with decreasing educational level and increasing severity of mental health conditions in all age strata, but most in women aged ≥31 years. The highest absolute risk was 12.9% [95% CI: 11.2;14.8%] in women aged ≥31 years with low education and moderate/severe mental health conditions resulting in a relative risk of 2.23 [95% CI: 1.93–2.58] compared to the unexposed reference group in that age strata. We found positive additive interaction between low education and mental health conditions in women aged 24–30 and ≥ 31 years and between age ≥ 31 years and combinations of mental health conditions and educational levels.ConclusionThe inequality in preterm birth increased with increasing age. To reduce inequality in preterm birth focused attention on women with higher age further combined with lower educational levels and mental health conditions is essential.

Mindfulness in Pregnancy: A Brief Intervention for Women at Risk.

The U.S. has the highest rate of preterm birth (PTB), of all developed countries, especially among African American women. Social determinants of health and inequalities in health outcomes are understudied areas. The intersectionality of race and socioeconomic status has been shown to contribute to chronic stress, stress has been shown to be associated with PTB, yet the mechanisms that affect pregnancy outcomes have not been explicit. Mindfulness-based Interventions that address stress reduction during pregnancy may improve quality of life during pregnancy, perhaps enhancing resilience, and be on the pathway to reducing the risk of negative pregnancy outcomes such as PTB. We over-enrolled African American women and those covered by Medicaid to reach women at higher risk for PTB and included women in substance use treatment. Participants were enrolled in a 6-week mindfulness in pregnancy (MIP) intervention at the obstetric clinic. Sociodemographic characteristics and psychosocial assessments were obtained at three time points. We enrolled 35 women who self-identified as: non-white, Medicaid recipients, aged 25-35years, with high school or less education. We found reductions in perceived stress, pregnancy specific stress, trait anxiety and depression and increases in mindfulness that sustained post-intervention at 2 and 7months. Social determinants and stress in particular have been associated with negative birth outcomes. This paper describes a brief intervention and results of MIP tailored to women who have significantly more stress due to race, poverty, homelessness, substance use treatment and other comorbid health risks including PTB.

Antenatal Azithromycin to Prevent Preterm Birth in Pregnant women with Vaginal Cerclage. A Randomized Controlled Trial

Abstract Background Preterm birth with its complications is one of the leading causes of perinatal morbidity and mortality, as well as maternal morbidity, especially in low and middle-income countries. Cervical cerclage is a well-established preventive tool in women at high risk of preterm birth; however, subclinical maternal infection might still cause failure of this method. Thus, adding prophylactic antibiotics, namely macrolides, could prevent preterm birth. Patients and methods This was a randomized controlled clinical trial involving two groups of women who underwent vaginal cerclage at Ain Shams University Maternity Hospital. One group received azithromycin 500mg one tablet orally once daily for 3 days every month from 14th week to 34th week gestation, in addition to routine antenatal care; while the other group received usual antenatal care without antibiotic prophylaxis after cerclage. Follow-up was done and we compared the outcomes in each group: gestational age at delivery, birth weight, mode of delivery, maternal complications, and perinatal complications. ClinicalTrials.gov Identifier NCT04278937. Results Gestational age at delivery was significantly higher in the azithromycin group (36.8weeks vs 34.1weeks; P = 0.017), with significant prolongation of gestation in the azithromycin group (23.7weeks vs 21.1weeks; P = 0.005). As regards birth weight, it was significantly higher in the azithromycin group (2932.6gm vs 2401.8gm; P = 0.006); however babies with low birth weight (birth weight &amp;lt;2500gm) were non-significantly less frequent in the azithromycin group (3cases vs 7cases; P = 0.165). There was no significant difference between the two groups as regards other outcomes (miscarriage, stillbirth, neonatal intensive care unit admission, antepartum hemorrhage, postpartum pyrexia, need for blood transfusion). Conclusion Adding azithromycin as antenatal prophylaxis in women undergoing vaginal cerclage prolongs pregnancy and reduces risk of PTB, with slight increase in birth weight. However, there was no clear effect on incidence of low birth weight, or perinatal morbidity/mortality.