Term Labor Research Articles

Prostaglandin F2α regulates mitochondrial dynamics and mitophagy in the bovine corpus luteum.

Prostaglandins are arachidonic acid-derived lipid mediators involved in numerous physiological and pathological processes. PGF2α analogues are therapeutically used for regulating mammalian reproductive cycles and blood pressure, inducing term labor, and treating ocular disorders. PGF2α exerts effects via activation of calcium and PKC signaling, however, little is known about the cellular events imposed by PGF2α signaling. Here, we explored the early effects of PGF2α on mitochondrial dynamics and mitophagy in the bovine corpus luteum employing relevant and well characterized in vivo and in vitro approaches. We identified PKC/ERK and AMPK as critical protein kinases essential for activation of mitochondrial fission proteins, DRP1 and MFF. Furthermore, we report that PGF2α elicits increased intracellular reactive oxygen species and promotes receptor-mediated activation of PINK-Parkin mitophagy. These findings place the mitochondrium as a novel target in response to luteolytic mediator, PGF2α. Understanding intracellular processes occurring during early luteolysis may serve as a target for improving fertility.

The effect of vaginal administration of isosorbide mononitrate on cervical ripening and induction of labour in term and post term pregnancy

The effect of vaginal administration of isosorbide mononitrate on cervical ripening and induction of labour in term and post term pregnancy

Use of External Uterine Electromyography Across Stage I Labor.

Highly sensitive, external uterine electromyography (EMG) measures myometrial electrical activity and is noninvasive compared with the clinical intrauterine pressure catheter. Most experimental studies have measured EMG in 30-minute epochs, limiting the utility of this instrumentation in intrapartum clinical practice. To test proof of concept, surface uterine EMG contraction activity was continuously collected throughout the first stage of labor from healthy women at term gestation with (n = 3) and without (n = 1) epidural or combined spinal-epidural analgesia for a maximal length of 11 hours and 24 minutes. EMG activity was recorded concurrently with tocodynamometer (toco) signals, using a pair of electrodes on the left and right sides of the maternal umbilicus with grounds attached to both hips of the reclining woman in labor. The preamplifier cutoff frequency settings were appropriate to monitor smooth muscle contraction in labor, with the analog high-pass filter set at 0.05 Hz and the low-pass filter at 1.50 Hz. Signals were sampled at 100 Hz, transmitted to a computer, and visualized by Chart 4.2 software. EMG data from epochs at baseline, during the pre-epidural fluid bolus and at the 60-minute post-epidural test dose, and at 3, 5, 6, and 8 cm dilatation were analyzed for burst power spectrum peak frequency (Hz), burst power spectrum amplitude (mV2 ), and burst duration (seconds). Uterine EMG contractile bursts were preceded and followed by a stable baseline and coincided with toco contractions. Movement artifacts were negligible, and large movement artifacts were easily distinguishable. The EMG bursts and toco contractions remained clearly identifiable, even when one woman without epidural analgesia stood beside the bed laboring for approximately 10 minutes. Burst spectral components fell within the expected 0.34-to-1.00 Hz range for term labor. High-quality data demonstrate that EMG instrumentation effectively and accurately measures uterine contraction parameters across the first stage of term labor.

Nuchal Cord Encirclement & Birth Weight

Nuchal cord encirclement is defined as the condition in which the umbilical cord is wound at least once around the neck of the fetus. The ultrasound is one of the very helpful tools for evaluation of fetus with possible Nuchal cord entanglement, especially color flow Doppler ultrasonography which is a reliable tool to detect Nuchal coiling of the umbilical cord, and therefore color Doppler waveforms assessment in nuchal cord entanglements might be helpful for clinicians to decide a closer surveillance in labor by using intra-partum cardio-toco-graphy. The aim of the study was to determine if the presence of a single or multiple nuchal cord encirclement has a negative effect on fetal growth. This study was conducted at Tikrit Teaching Hospital. All live borns, single and multiple births during the study period (August 2008 to July 2009) were examined they were 3972 including term and preterm labor. Of them 271 have nuchal cord encirclement, of those 34 have multiple encirclement and 23 7 have single encirclement. The collected data were divided into those with encirclement and those without. The effect of nuchal cord on the birth weight according to the gestational age; sex of the neonate and the parity of the mother hc1s been evaluated. There was no significant association between the diagnosis of growth restriction and the presence of cord encirclement. The mean birth weight was not significantly different in the presence of a single or multiple nuchal cord encirclement than without encirclement. The conclusion was that whether the nuchal cord encirclement is single or multiple, it has no significant effect on birth weight.

COMPARATIVE ANALYSIS OF SERUM MAGNESIUM & ZINC LEVELS AND THEIR ASSOCIATIONS WITH PRETERM LABOUR

Background: Preterm is dened as babies born alive before 37 weeks of pregnanc, it occurs when there is a regular contraction of uterus which results in opening of cervix after 20 weeks and before 37 weeks of gestation. preterm labour is spontaneous but it can also be due to a biochemical changes in body functions at the cellular level of trace elements such as magnesium and zinc. The main objective of this study is to nd the association of hypomagnesaemia and low zinc levels in preterm delivered women and to compare the maternal serum magnesium and zinc levels between Preterm and Term delivered mothers. Methods: A Comparative study was done in the Department of Biochemistry, Andhra Medical College, Visakhapatnam. Atotal of 126 women who were admitted to the labour room at Department of Obstetrics and gynaecology, King George Hospital, Visakhapatnam were selected for this study. All the subjects were divided into two groups as Preterm Consists of 63 women with spontaneous preterm labour delivered between 28- 37 weeks and Term Consists of 63 Women with Term labour after 37 weeks. Results: Women with Preterm labour had a signicantly low serum magnesium level with a mean serum magnesium level of 1.8 mg/dl with SD of 0.38 whereas the patients with Term labour had a mean serum magnesium level of 2.09 mg/dl with SD of 0.50 and also low zinc levels in Preterm labour with mean zinc levels of 51.28 µg/dl with SD 10.9 whereas patients with Term labour had mean serum zinc levels of 56.5 µg/dl with SD 9.7. The difference of serum magnesium and zinc levels observed between the study population and control population is independent of factors like maternal age, parity, gestational age, Blood pressure and socioeconomic status. In this study there is non signicant weak correlation was found between Demographic data and parametric data. Conclusions:Serum magnesium and zinc levels can be used as predictors for preterm labour. Spontaneous preterm delivery can be avoided by early assessment of maternal magnesium and zinc status and also by simple oral supplementation of magnesium and zinc which might provide an easy and inexpensive means to decrease the problems related to preterm labour. There is a further scope for research on serum magnesium and zinc levels based on gestational age.

Integrating single-cell RNA sequencing with spatial transcriptomics reveals an immune landscape of human myometrium during labour.

The transition of the myometrium from a quiescent to a contractile state during labour is known to involve inflammation, which is characterized by the infiltration of immune cells and the secretion of cytokines. However, the specific cellular mechanisms underlying inflammation in the myometrium during human parturition are not yet fully understood. Through the analysis of transcriptomics, proteomics, and cytokine arrays, the inflammation in the human myometrium during labour was revealed. By performing single-cell RNA sequencing (scRNA-seq) and spatiotemporal transcriptomic (ST) analyses on human myometrium in term in labour (TIL) and term in non-labour (TNL), we established a comprehensive landscape of immune cells, their transcriptional characteristics, distribution, function and intercellular communications during labour. Histological staining, flow cytometry, and western blotting were applied to validate some results from scRNA-seq and ST. Our analysis identified immune cell types, including monocytes, neutrophils, T cells, natural killer (NK) cells and B cells, present in the myometrium. TIL myometrium had a higher proportion of monocytes and neutrophils than TNL myometrium. Furthermore, the scRNA-seq analysis showed an increase in M1 macrophages in TIL myometrium. CXCL8 expression was mainly observed in neutrophils and increased in TIL myometrium. CCL3 and CCL4 were principally expressed in M2 macrophages and neutrophils-6, and decreased during labour; XCL1 and XCL2 were specifically expressed in NK cells, and decreased during labour. Analysis of cytokine receptor expression revealed an increase in IL1R2, which primarily expressed in neutrophils. Finally, we visualized the spatial proximity of representative cytokines, contraction-associated genes, and corresponding receptors in ST to demonstrate their location within the myometrium. Our analysis comprehensively revealed changes in immune cells, cytokines, and cytokine receptors during labour. It provided a valuable resource to detect and characterize inflammatory changes, yielding insights into the immune mechanisms underlying labour.

The Role of Fetal Membranes during Gestation, at Term, and Preterm Labor.

During pregnancy, the fetal membranes (i.e., amniochorionic membranes) surround the intrauterine cavity and provide mechanical, immune, and endocrine support to protect the fetus. Though they are a vital component of the intrauterine cavity, the fetal membranes are largely overlooked as an extension of the placenta, leading to a poor understanding of their role during gestation, parturition, or preterm birth. The fetal membranes are comprised of fetal cellular and stromal layers and line up with maternal decidua forming the feto-maternal interface during pregnancy. This interface plays a large role during pregnancy and the induction of term or preterm parturition (e.g., labor). Here we summarize the function of the fetal membranes focusing on their role during gestation at term, and during preterm births.

Noninvasive electromyometrial imaging of human uterine maturation during term labor

Electromyometrial imaging (EMMI) was recently developed to image the three-dimensional (3D) uterine electrical activation during contractions noninvasively and accurately in sheep. Herein we describe the development and application of a human EMMI system to image and evaluate 3D uterine electrical activation patterns at high spatial and temporal resolution during human term labor. We demonstrate the successful integration of the human EMMI system during subjects’ clinical visits to generate noninvasively the uterine surface electrical potential maps, electrograms, and activation sequence through an inverse solution using up to 192 electrodes distributed around the abdomen surface. Quantitative indices, including the uterine activation curve, are developed and defined to characterize uterine surface contraction patterns. We thus show that the human EMMI system can provide detailed 3D images and quantification of uterine contractions as well as novel insights into the role of human uterine maturation during labor progression.

Association of maternal body composition and diet on breast milk hormones and neonatal growth during the first month of lactation.

Preterm birth is associated with altered growth patterns and an increased risk of cardiometabolic diseases, with breast milk (BM) being a counteracting factor. Preterm infants also show alterations in adipokines and gut hormones influencing appetite and metabolism. Since these hormones are present in BM, it is possible that their levels may equilibrate deficiencies improving infant growth. We aimed to assess 1) the BM levels of ghrelin, resistin, leptin, insulin, peptide YY, and the gastrointestinal peptide in women with preterm and term labor; 2) the relationship between BM hormones and neonatal growth; and 3) the influence of maternal body composition and diet on these BM hormones. BM from 48 women (30 term and 18 preterm labor) was collected at days 7, 14, and 28 of lactation. Maternal body composition was evaluated by bioimpedance, and neonate anthropometric parameters were collected from medical records. The maternal dietary pattern was assessed by a 72-h dietary recall at days 7 and 28 of lactation. BM hormones were analyzed by the U-Plex Ultra-sensitive method. Data were analyzed using linear regression models. BM from women with preterm labor had lower ghrelin levels, with the other hormones being significantly higher compared to women with term delivery. In premature infants, growth was positively associated with BM ghrelin, while, in term infants, it was positively associated with insulin and negatively with peptide YY. In the first week of lactation, women with preterm labor had higher body fat compared to women with term labor. In this group, ghrelin levels were positively associated with maternal body fat and with fiber and protein intake. In women with term labor, no associations between anthropometric parameters and BM hormones were found, and fiber intake was negatively associated with peptide YY. Preterm labor is a factor influencing the levels of BM adipokines and gut hormones, with BM ghrelin being a relevant hormone for premature infant growth. Since ghrelin is lower in BM from women with preterm labor and the levels are associated with maternal fat storage and some dietary components, our data support the importance to monitor diet and body composition in women who gave birth prematurely to improve the BM hormonal status.

The amniotic fluid proteome changes with term labor and informs biomarker discovery in maternal plasma

The intra-uterine components of labor, namely, myometrial contractility, cervical ripening, and decidua/membrane activation, have been extensively characterized and involve a local pro-inflammatory milieu of cellular and soluble immune mediators. Targeted profiling has demonstrated that such processes extend to the intra-amniotic space, yet unbiased analyses of the proteome of human amniotic fluid during labor are lacking. Herein, we utilized an aptamer-based platform to characterize 1,310 amniotic fluid proteins and found that the proteome undergoes substantial changes with term labor (251 proteins with differential abundance, q < 0.1, and fold change > 1.25). Proteins with increased abundance in labor are enriched for immune and inflammatory processes, consistent with prior reports of labor-associated changes in the intra-uterine space. By integrating the amniotic fluid proteome with previously generated placental-derived single-cell RNA-seq data, we demonstrated the labor-driven upregulation of signatures corresponding to stromal-3 and decidual cells. We also determined that changes in amniotic fluid protein abundance are reflected in the maternal plasma proteome. Collectively, these findings provide novel insights into the amniotic fluid proteome in term labor and support its potential use as a source of biomarkers to distinguish between true and false labor by using maternal blood samples.

Chorioamnionitis secondary to Ureaplasma parvum infection: a case report.

Ureaplasma species are the most frequently isolated microorganisms in cases of spontaneous preterm labor, premature rupture of the membranes, or chorioamnionitis. A woman at 28+6 weeks of gestation with no apparent history of interest presented at the hospital with contractions. Upon suspicion of chorioamnionitis, the patient was admitted for a low segment transverse cesarean section, which was completed without any complications. The patient was discharged at 7days. The newborn remained stable and showed no clinical signs of infection. However, on suspicion of chorioamnionitis, empirical treatment with intravenous ampicillin (2g every 6h) and gentamicin (5mg/kg once daily) was initiated. Samples of pharyngeal/tonsillar, ear, and anal/rectal exudates were collected. At 24h, all samples were positive for Ureaplasma parvum. Empirical treatment was suspended, and treatment with intravenous azithromycin was initiated (12mg once daily). Endocervical and placental exudates were also positive for U.parvum. Fifty-two days after birth, the newborn was discharged. The relationship between Ureaplasma spp. colonization and perinatal disease seem to be clear. However, the high frequency of vaginal Ureaplasma spp. colonization and high rates of term labor among pregnant women with this colonization make further studies necessary.

The role of chemerin in the regulation of cGAS-STING pathway in gestational diabetes mellitus placenta.

Recent studies already confirmed that placenta mitochondrial dysfunction is associated with the progression of gestational diabetes mellitus (GDM). Besides, a possible relationship between adipokine chemerin and disulfide-bond A oxidoreductase-like protein (DsbA-L) had been revealed, whereas the potential interaction remains unclear. In addition, very little is still known about the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway and its mechanisms of action in the context of GDM. The present study aims to investigate the underlying mechanism of cGAS-STING pathway and its regulatory relationship with chemerin in GDM. A total of 50 participants, including 25 cases of GDM patients and 25 pregnant women with normal glucose tolerance, were enrolled, and their placenta tissues at term labor were collected. Besides, an insulin resistance cell model was established on the human trophoblastic cell line to explore the molecular mechanism of chemerin on cGAS-STING pathway. Results showed that there were mitochondrial pathological changes in GDM placenta, accompanied by the decreased expression of DsbA-L, increased level of chemerin, and the activation of cGAS-STING pathway. In the insulin resistant cell model, overexpression of chemerin upregulated protein expression of DsbA-L, and recombinant chemerin presented time-dependent inhibition on the cGAS-STING pathway, but this effect was not dependent on DsbA-L. In conclusion, elevated chemerin is probably a protective mechanism, which may be a potential therapeutic strategy for GDM.

20α-Hydroxysteroid Dehydrogenase Expression in the Human Myometrium at Term and Preterm Birth: Relationships to Fetal Sex and Maternal Body Mass Index

The mechanism by which human labor is initiated in the presence of elevated circulating progesterone levels remains unknown. Recent evidence indicates that the progesterone-metabolizing enzyme, 20α-hydroxysteroid dehydrogenase (20α-HSD), encoded by the gene AKR1C1, may contribute to functional progesterone withdrawal. We found that AKR1C1 expression significantly increased with labor onset in term myometrium, but not in preterm myometrium. Among preterm laboring deliveries, clinically diagnosed chorioamnionitis was associated with significantly elevated AKR1C1 expression. AKR1C1 expression positively correlated with BMI before labor and negatively correlated with BMI during labor. Analysis by fetal sex showed that AKR1C1 expression was significantly higher in women who delivered male babies compared to women who delivered female babies at term, but not preterm. Further, in pregnancies where the fetus was female, AKR1C1 expression positively correlated with the mother’s age and BMI at the time of delivery. In conclusion, the increase in myometrial AKR1C1 expression with term labor is consistent with 20α-HSD playing a role in local progesterone metabolism to promote birth. Interestingly, this role appears to be specific to term pregnancies where the fetus is male. Upregulated AKR1C1 expression in the myometrium at preterm in-labor with clinical chorioamnionitis suggests that increased 20α-HSD activity is a mechanism through which inflammation drives progesterone withdrawal in preterm labor. The link between AKR1C1 expression and maternal BMI may provide insight into why maternal obesity is often associated with dysfunctional labor. Higher myometrial AKR1C1 expression in male pregnancies may indicate fetal sex-related differences in the mechanisms that precipitate labor onset at term.

The Association of Fetal Acidemia With Adverse Neonatal Outcomes at Time of Scheduled Cesarean Delivery

ABSTRACT Up to 30% of term labor deliveries experience fetal acidemia, a condition usually caused by hypoxia that is associated with adverse neonatal outcomes. The American College of Obstetricians and Gynecologists and American Academy of Pediatrics recommend assessing fetal umbilical artery (UA) blood gases at delivery when fetal metabolic status is in question. Although a UA pH of 7.24 to 7.28 is considered normal, the degree of acidemia associated with neonatal death is unclear. Recent data suggest that mild acidemia (UA pH of 7.0–7.2) and certain types of acidemia (metabolic, mixed, or respiratory) also indicate increased risk for adverse outcomes. Most cases of acidemia follow labor when the placental gas exchange is interrupted during contractions. But fetal acidemia is rare in cases of scheduled prelabor cesarean delivery (CD) and not well described in the literature. This study aims to determine if fetal acidemia at the time of scheduled, prelabor CD is associated with neonatal morbidity. This was a retrospective cohort study comparing patients with and without fetal acidemia, defined as a UA pH &lt;7.2. Included were singleton neonates delivered via scheduled CD at a single tertiary care center from June 2004 to December 2014. Excluded were those who delivered before 37 weeks of gestation, were diagnosed with major anomalies, or underwent CD due to labor, rupture of membranes, or nonreassuring fetal status. Also excluded were cases in which data on validated umbilical cord gases were unavailable. The primary outcome was a composite of neonatal outcomes, including neonatal death, encephalopathy, therapeutic hypothermia, seizures, intubation, and respiratory distress. A total of 2081 neonates met the inclusion criteria, with fetal acidemia present at the time of delivery in 252 cases (12.1%). Acidemia occurred more frequently in breech neonates and those born to mothers with gestational diabetes mellitus or obesity. Intraoperative maternal hypotension, use of vasopressor therapy, and increased times from anesthesia induction and skin incision to delivery were also more likely to occur in cases of acidemia. The primary composite outcome was observed in 176 (8.5%) of neonates. This outcome was significantly higher in those with acidemia than those without (7.6% vs 15.1%; adjusted risk ratio [aRR], 2.95; 95% confidence interval [CI], 2.03 to 4.12). Intubation (aRR 3.50; 95% CI, 1.27–9.13) and respiratory distress (aRR, 2.93; 95% CI, 2.00–4.13) also occurred more frequently among those with acidemia. As the rate of UA pH categories decreased, the proportion of neonates with the primary outcome increased: 13.5% morbidity if UA pH was 7.0 to 7.19 versus 42.9% morbidity if UA pH was &lt;7.0. Compared with neonates with a UA pH ≥7.2, the risk for adverse outcomes rose 3.2-fold in those with a UA pH &lt;7.1 (aRR, 3.23; 95% CI, 1.73–5.24) and 6.6-fold in those with a UA pH &lt;7.0 (aRR, 6.64; 95% CI, 3.23–8.96). The primary outcome was observed in 24.7% of neonates with respiratory acidemia, 27.5% with mixed, and 25% with other acidemia. There were no cases of metabolic acidemia. Compared with neonates without acidemia, the risk for adverse outcomes after controlling for confounders increased 2.7-fold in those with respiratory acidemia (adjusted odds ratio, 2.77; 95% CI, 1.74–4.15) and 3-fold in those with mixed acidemia (adjusted odds ratio, 3.08; 95% CI, 1.72–4.93). In conclusion, there was an increased risk of adverse neonatal outcomes in cases with mild fetal acidemia at the time of scheduled CD. Most cases in this study were attributed to respiratory acidemia.

Term Idiopathic Polyhydramnios, and Labor Complications.

Background and Aim: Polyhydramnios is associated with an increased risk of various adverse pregnancy outcomes, yet complications during labor have not been sufficiently studied. We assessed the labor and perinatal outcomes of idiopathic polyhydramnios during term labor. Methods: Retrospective cohort study at a tertiary medical center between 2010 and 2014. Women with idiopathic polyhydramnios defined as an amniotic fluid index (AFI) greater than 24 cm or a deep vertical pocket (DVP) > 8 cm (cases) were compared with women with a normal AFI (5-24 cm) (controls). Statistics: Descriptive, means ± SDs, medians + IQR. Comparisons: chi-square, Fisher's exact test, Mann-Whitney Test, multivariate logistic models. Results: During the study period 11,065 women had ultrasound evaluation completed by a sonographer within two weeks of delivery. After excluding pregnancies complicated by diabetes (pre-gestational or gestational), fetal anomalies, IUFD, multifetal pregnancies, elective cesarean deliveries (CD) or missing data, we included 750 cases and 7000 controls. The degree of polyhydramnios was mild in 559 (75.0%) cases (AFI 24-30 cm or DVP 8-12 cm), moderate in 137 (18.0%) cases (30-35 cm or DVP 12-15 cm) and severe in 54 (7.0%) cases (AFI >35 cm or DVP > 15 cm). Idiopathic polyhydramnios was associated with a higher rate of CD 9.3% vs. 6.2%, p = 0.004; a higher rate of macrosomia 22.8% vs. 7.0%, p < 0.0001; and a higher rate of neonatal respiratory complications 2.0% vs. 0.8%, p = 0.0001. A multivariate regression analysis demonstrated an independent relation between polyhydramnios and higher rates of CD, aOR 1.62 (CI 1.20-2.19 p = 0.002) and composite adverse neonatal outcome aOR 1.28 (CI 1.01-1.63 p = 0.043). Severity of polyhydramnios was significantly associated with higher rates of macrosomia and CD (p for trend <0.01 in both). Conclusions: The term idiopathic polyhydramnios is independently associated with macrosomia, CD and neonatal complications. The severity of polyhydramnios is also associated with macrosomia and CD.

Caspase-3, Caspase-8 and XIAP Gene Expression in the Placenta: Exploring the Causes of Spontaneous Preterm Labour.

A better understanding of the pathogenesis of preterm birth (PTB) will allow us to lower the PTB rate, reducing perinatal morbidity and mortality. This article presents the hypothesis that premature placenta apoptosis could be a potential cause of PTB. We evaluated gene expression involved in apoptosis: caspase-3, caspase-8, and XIAP (X-linked inhibitor of apoptosis) in the placenta during pregnancy (n = 41), at the onset of preterm labour (n = 42), after preterm (n = 44) and term (n = 32) labour. We used RNA extraction, reverse transcription, and PCR. During pregnancy the gene expression of caspase-3 and caspase-8 is low, but XIAP is higher than the caspases. At the onset of preterm labour, we observed a significantly increased expression of both caspase-8 (10.7-fold, p < 0.01) and caspase-3 (2.5-fold, p < 0.01) and XIAP (3-fold; p < 0.05) compared with expression during pregnancy. Our study showed that during pregnancy, the expression of caspase genes in the placenta is low and probably controlled by high XIAP expression. At the onset of preterm labour, the expression of caspase genes increases sharply. This may initiate the onset of preterm labour.

Uterine activity modifies the response of the fetal autonomic nervous system at preterm active labor.

The autonomic nervous system of preterm fetuses has a different level of maturity than term fetuses. Thus, their autonomic response to transient hypoxemia caused by uterine contractions in labor may differ. This study aims to compare the behavior of the fetal autonomic response to uterine contractions between preterm and term active labor using a novel time-frequency analysis of fetal heart rate variability (FHRV). We performed a case-control study using fetal R-R and uterine activity time series obtained by abdominal electrical recordings from 18 women in active preterm labor (32-36 weeks of gestation) and 19 in active term labor (39-40 weeks of gestation). We analyzed 20 minutes of the fetal R-R time series by applying a Continuous Wavelet Transform (CWT) to obtain frequency (HF, 0.2-1Hz; LF, 0.05-0.2Hz) and time-frequency (Flux0, Flux90, and Flux45) domain features. Time domain FHRV features (SDNN, RMSSD, meanNN) were also calculated. In addition, ultra-short FHRV analysis was performed by segmenting the fetal R-R time series according to episodes of the uterine contraction and quiescent periods. No significant differences between preterm and term labor were found for FHRV features when calculated over 20 minutes. However, we found significant differences when segmenting between uterine contraction and quiescent periods. In the preterm group, the LF, Flux0, and Flux45 were higher during the average contraction episode compared with the average quiescent period (p<0.01), while in term fetuses, vagally mediated FHRV features (HF and RMSSD) were higher during the average contraction episode (p<0.05). The meanNN was lower during the strongest contraction in preterm fetuses compared to their consecutive quiescent period (p=0.008). The average autonomic response to contractions in preterm fetuses shows sympathetic predominance, while term fetuses respond through parasympathetic activity. Comparison between groups during the strongest contraction showed a diminished fetal autonomic response in the preterm group. Thus, separating contraction and quiescent periods during labor allows for identifying differences in the autonomic nervous system cardiac regulation between preterm and term fetuses.

Enhancing classification of preterm-term birth using continuous wavelet transform and entropy-based methods of electrohysterogram signals.

Despite vast research, premature birth's electrophysiological mechanisms are not fully understood. Prediction of preterm birth contributes to child survival by providing timely and skilled care to both mother and child. Electrohysterography is an affordable, noninvasive technique that has been highly sensitive in diagnosing preterm labor. This study aimed to choose the more appropriate combination of characteristics, such as electrode channel and bandwidth, as well as those linear, time-frequency, and nonlinear features of the electrohysterogram (EHG) for predicting preterm birth using classifiers. We analyzed two open-access datasets of 30 minutes of EHG obtained in regular checkups of women around 31 weeks of pregnancy who experienced premature labor (P) and term labor (T). The current approach filtered the raw EHGs in three relevant frequency subbands (0.3-1 Hz, 1-2 Hz, and 2-3Hz). The EHG time series were then segmented to create 120-second windows, from which individual characteristics were calculated. The linear, time-frequency, and nonlinear indices of EHG of each combination (channel-filter) were fed to different classifiers using feature selection techniques. The best performance, i.e., 88.52% accuracy, 83.83% sensitivity, and 93.22% specificity, was obtained in the 2-3 Hz bands using Medium Frequency, Continuous Wavelet Transform (CWT), and entropy-based indices. Interestingly, CWT features were significantly different in all filter-channel combinations. The proposed study uses small samples of EHG signals to diagnose preterm birth accurately, showing their potential application in the clinical environment. Our results suggest that CWT and novel entropy-based features of EHG could be suitable descriptors for analyzing and understanding the complex nature of preterm labor mechanisms.

National PReCePT Programme: a before-and-after evaluation of the implementation of a national quality improvement programme to increase the uptake of magnesium sulfate in preterm deliveries

ObjectiveTo evaluate the effectiveness and cost-effectiveness of the National PReCePT Programme (NPP) in increasing use of magnesium sulfate (MgSO4) in preterm births.DesignBefore-and-after study.SettingMaternity units (N=137) within NHS England and the...

Methods of induction of labour: a network meta-analysis

Objectives This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To compare the effectiveness and safety profiles for the different methods of cervical ripening and labour induction at or beyond term labour using network meta‐analysis, and to provide rankings of the available treatments according to their effectiveness and safety profile.