Preterm birth rate and dilemma of preterm labor treatment in Asia

Unraveling the role of the gut microbiome in pregnancy disorders: insights and implications

The gut microbiota is the collective term for the microorganisms that reside in the human gut. In recent years, advances in sequencing technology and bioinformatics gradually revealed the role of gut microbiota in human health. Dramatic changes in the gut microbiota occur during pregnancy due to hormonal and dietary changes, and these changes have been associated with certain gestational diseases such as preeclampsia (PE) and gestational diabetes mellitus (GDM). Modulation of gut microbiota has also been proposed as a potential treatment for these gestational diseases. The present article aims to review current reports on the association between gut microbiota and gestational diseases, explore possible mechanisms, and discuss the potential of probiotics in gestational diseases. Uncovering the link between gut microbiota and gestational diseases could lead to a new therapeutic approach.

Pregnancy with mixed connective tissue disease: Exploration of factors influencing live birth outcomes

Mixed connective tissue disease (MCTD) predominantly affects women in their reproductive age (30-40 years). This study is aimed to analyze a case series of MCTD-complicated pregnancies. The study design utilized a combined case-series and case-control approach. Pregnant women with MCTD were included and categorized into two groups: the live-birth and non-live birth (encompassing miscarriages at <12 weeks and stillbirths at ≥12 weeks) groups. Primary outcomes included delivery outcomes and factors associated with live births. A total of 57 pregnancies from 34 mothers (median age: 33.0 years) were included. Regarding delivery outcomes, the rates for live birth, miscarriage, and stillbirth were 64.9, 29.8, and 5.3%, respectively. Additionally, the respective rates of preterm delivery, fetal growth restriction (FGR), and small-for-gestational-age (SGA) were 18.9, 18.9, and 27.0%. Higher steroid usage (62.2 vs. 30.0%, p = 0.02) and lower prednisolone dosage in the live birth group (median dose: 7 vs. 10 mg, p = 0.03) were found to be significant factors contributing to live births. MCTD during pregnancy was associated with increased risks of miscarriage, stillbirth, preterm delivery, FGR, and SGA. Notably, low-dose steroid therapy was identified as a contributing factor to successful live births.

Assessing the Potency of the Novel Tocolytics 2-APB, Glycyl-H-1152, and HC-067047 in Pregnant Human Myometrium

The intracellular signaling pathways that regulate myometrial contractions can be targeted by drugs for tocolysis. The agents, 2-APB, glycyl-H-1152, and HC-067047, have been identified as inhibitors of uterine contractility and may have tocolytic potential. However, the contraction-blocking potency of these novel tocolytics was yet to be comprehensively assessed and compared to agents that have seen greater scrutiny, such as the phosphodiesterase inhibitors, aminophylline and rolipram, or the clinically used tocolytics, nifedipine and indomethacin. We determined the IC₅₀ concentrations (inhibit 50% of baseline contractility) for 2-APB, glycyl-H-1152, HC-067047, aminophylline, rolipram, nifedipine, and indomethacin against spontaneous ex vivo contractions in pregnant human myometrium, and then compared their tocolytic potency. Myometrial strips obtained from term, not-in-labor women, were treated with cumulative concentrations of the contraction-blocking agents. Comprehensive dose-response curves were generated. The IC₅₀ concentrations were 53 µM for 2-APB, 18.2 µM for glycyl-H-1152, 48 µM for HC-067047, 318.5 µM for aminophylline, 4.3 µM for rolipram, 10 nM for nifedipine, and 59.5 µM for indomethacin. A single treatment with each drug at the determined IC₅₀ concentration was confirmed to reduce contraction performance (AUC) by approximately 50%. Of the three novel tocolytics examined, glycyl-H-1152 was the most potent inhibitor. However, of all the drugs examined, the overall order of contraction-blocking potency in decreasing order was nifedipine > rolipram > glycyl-H-1152 > HC-067047 > 2-APB > indomethacin > aminophylline. These data provide greater insight into the contraction-blocking properties of some novel tocolytics, with glycyl-H-1152, in particular, emerging as a potential novel tocolytic for preventing preterm birth.

Preterm birth update in Australasia: A report of the international symposium of Preterm Birth International Collaborative-Australasia branch

Preterm birth (PTB) is one of the most important problems that pose dilemmas for both the obstetrician and neonatologist, placing a heavy burden psychologically and financially on the families involved, and triggering high socio-economic costs to the public healthcare. The rate of PTB in Asian countries has been ranked at top globally. To reduce the PTB rate, to promote the prevention and intervention for PTB, and to better understand the pathophysiology underlying PTB, the Preterm Birth International Collaborative Australia branch (PREBIC-AA) was launched in 2017. A series scientific activities including organizing annual research symposiums has been planned and organized among Australasian countries. Here we briefly updated the current progress in clinical management and translational research on PTB in Australasian countries that have been participated in PREBIC-AA.

Report from "International Workshop for Junior Fellows 2: Tocolytic treatment for prevention of preterm birth" at the 73rd Annual Congress of the Japan Society of Obstetrics and Gynecology

At the 73rd Annual Congress of the Japan Society of Obstetrics and Gynecology, we discussed recent tocolytic treatments for the prevention of preterm birth with obstetricians from Korea and Taiwan. The rate of preterm birth in our countries has been increasing, and optimal tocolytic treatments are of great concern. Ritodrine hydrochloride was the first available drug for tocolysis in our countries and is often administered for over 48 h, although it is not recommended for maintenance therapy in Western countries. Meanwhile, there are differences in the use of other tocolytic drugs, based on approval of the drugs and the health insurance systems. Nifedipine and atosiban have not been considered first-line agents in Japan. The long-term use of unnecessary tocolysis should be avoided, and the introduction of other tocolytic drugs, including nifedipine or atosiban, should be discussed.

Learning From Strengths: Improving Care by Comparing Perinatal Approaches Between Japan and Canada and Identifying Future Research Priorities

OBJECTIVE

Preterm birth (PTB) is the leading cause of infant morbidity and mortality worldwide. Canada and Japan each have strengths that can inform clinical decision-making, research, and health care policy regarding the prevention of PTB and its sequelae. Our objectives were to: 1) compare PTB rates, risk factors, management, and outcomes between Japan and Canada; 2) establish research priorities while fostering future collaborative opportunities; and 3) undertake knowledge translation of these findings.

METHODS

We conducted a literature review to identify publications that examined PTB rates, risk factors, prevention and management techniques, and outcomes in Japan and Canada. We conducted site visits at 4 Japanese tertiary centres and held a collaborative stakeholder meeting of parents, neonatologists, maternal-fetal medicine specialists, and researchers.

RESULTS

Japan reports lower rates of PTB, neonatal mortality, and several PTB risk factors than Canada. However, Canadian PTB data is population-based, whereas, in Japan, the rate of PTB is population-based, but outcomes are not. Rates of severe neurologic injury and necrotizing enterocolitis were lower in Japan, while Canada's rates of bronchopulmonary dysplasia and retinopathy of prematurity were lower. PTB prevention approaches differed, with less progesterone use in Japan and more long-term tocolysis. In Japan, there were lower rates of neonatal transfers and non-faculty overnight care, but also less use of antenatal corticosteroids and deferred cord clamping. Research priorities identified through the stakeholder meeting included early skin-to-skin contact, parental well-being after PTB, and transitions in care for the child.

CONCLUSION

We identified key differences between Japan and Canada in the factors affecting PTB management and patient outcomes, which can inform future research efforts.

The intervention effect of nicotine on cervical fibroblast-myofibroblast differentiation in lipopolysaccharide-induced preterm birth model through activating the TGF-β1/Smad3 pathway

Currently, the clinical treatment of preterm birth, mainly using uterine contraction inhibitors, does not fundamentally reduce the incidence of premature birth (PTB). Premature cervical ripening is an important factor in PTB. We previously found that nicotine-treated pregnant murine had significant cervical resistance to stretch and higher collagen cross-links compared to the control animals, and nicotine prolonged gestation and inhibited cervical ripening. However, the regulatory effects of nicotine on premature cervical ripening and its role in PTB remain unclear. To investigate the effects of nicotine on cervical TGF-β1/Smad3 pathway and fibroblast-myofibroblast differentiation regulated by this pathway in PTB-like models. Intraperitoneal injection with 15 μg lipopolysaccharide (LPS) in 200 μl PBS into pregnant mice was used to induce the PTB-like model. Mice were randomly divided into four groups: control group, LPS-treated group, LPS + Nicotine co-treated group and LPS + Nicotine+α-BGT co-treated group. Pregnancy outcomes were monitored. The collagen content was assessed by Picrosirius red staining. Expressions of genes and proteins in the TGF-β/Smad3 pathway were detected by double immunofluorescence staining and quantitative Real-time PCR (qRT-PCR). myofibroblast differentiation were investigated by double immunofluorescence staining and qRT-PCR. Ultrastructures were analyzed by conventional transmission electron microscopy. The rate of PTB and neonatal mortality at birth was significantly higher in the LPS-treated group than in the control group; collagen content also decreased remarkably; the expression of TGF-β1 in macrophages and p-Smad3 in fibroblasts were reduced; the expression of α-smooth muscle actin (α-SMA, markers for activated fibroblasts) was down-regulated while the expression of calponin and smoothelin (markers for fibroblasts at rest) was up-regulated. Nicotine improved pregnancy outcomes and inhibited collagen degradation, activated the TGF-β1/Smad3 pathway and promoted cervical fibroblast-myofibroblast differentiation in PTB-like mice; such effects could be reversed by α-bungarotoxin (α-BGT). Nicotine inhibited premature cervical ripening in PTB-like models in relation with up-regulating the TGF-β/Smad3 pathway and promoting fibroblast to differentiate into myofibroblasts.

Folic Acid and Risk of Preterm Birth: A Meta-Analysis

The results from epidemiologic studies linking blood folate concentrations, folic acid supplementation, or dietary folate to the risk of preterm birth are inconsistent. In this study, we aimed to summarize the available evidence on these associations. A systematic search of the PubMed/MEDLINE, Google Scholar, Web of Science, and Cochrane Library databases up to October 20, 2018 was performed and reference lists of retrieved articles were screened. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the highest vs. the lowest levels of folate concentrations, folic acid supplementation, and dietary folate were calculated using random-effects models. Subgroup analyses and univariate meta-regression were performed to explore the sources of heterogeneity. Ten studies (six prospective cohort studies and four case-control studies) were included on folate concentrations, 13 cohort studies were included about folic acid supplementation, and 4 cohort studies were included regarding dietary folate intake. Higher maternal folate levels were associated with a 28% reduction in the risk of preterm birth (OR 0.72, 95% CI 0.56–0.93). Higher folic acid supplementation was associated with 10% lower risk of preterm birth (OR 0.90, 95% CI 0.85–0.95). In addition, a significant negative association was observed between dietary folate intake and the risk of preterm birth (OR 0.68, 95% CI 0.55–0.84), but no significant relation was seen between dietary folate and the risk of spontaneous preterm birth (OR 0.89, 95% CI 0.57–1.41). In the subgroup analysis, higher maternal folate levels in the third trimester were associated with a lower risk of preterm birth (OR 0.58, 95% CI 0.36–0.94). To initiate taking folic acid supplementation early before conception was adversely associated with preterm birth risk (OR 0.89, 95% CI 0.83–0.95). In conclusion, higher maternal folate levels and folic acid supplementation were significantly associated with a lower risk of preterm birth. The limited data currently available suggest that dietary folate is associated with a significantly decreased risk of preterm birth.