Fetal head descent assessed by transabdominal ultrasound: a prospective observational study.

BACKGROUND: Determining fetal head descent, expressed as fetal head station and engagement is an essential part of monitoring progression in labor. Assessing fetal head station is based on the distal part of the fetal skull, whereas assessing engagement is based on the proximal part. Prerequisites for assisted vaginal birth are that the fetal head should be engaged and its lowermost part at or below the level of the ischial spines. The part of the fetal head above the pelvic inlet reflects the true descent of the largest diameter of the skull. In molded (reshaped) fetal heads, the leading bony part of the skull may be below the ischial spines while the largest diameter of the fetal skull still remains above the pelvic inlet. An attempt at assisted vaginal birth in such a situation would be associated with risks. Therefore, the vaginal or transperineal assessments of station should be supplemented with a transabdominal examination. We suggest a method for the assessment of fetal head descent with transabdominal ultrasound. OBJECTIVE: To investigate the correlation between transabdominal and transperineal assessment of fetal head descent, and to study fetal head shape at different labor stages and head positions. STUDY DESIGN: Women with term singleton cephalic pregnancies admitted to the labor ward for induction of labor or in spontaneous labor, at the Cairo University Hospital and Oslo University Hospital from December 2019 to December 2020 were included. Fetal head descent was assessed with transabdominal ultrasound as the suprapubic descent angle between a longitudinal line through the symphysis pubis and a line from the upper part of the symphysis pubis extending tangentially to the fetal skull. We compared measurements with transperineally assessed angle of progression and investigated interobserver agreement. We also measured the part of fetal head above and below the symphysis pubis at different labor stages. RESULTS: The study population comprised 123 women, of whom 19 (15%) were examined before induction of labor, 8 (7%) in the latent phase, 52 (42%) in the active first stage and 44 (36%) in the second stage. The suprapubic descent angle and the angle of progression could be measured in all cases. The correlation between the transabdominal and transperineal measurements was -0.90 (95% confidence interval, -0.86 to -0.93). Interobserver agreement was examined in 30 women and the intraclass correlation coefficient was 0.98 (95% confidence interval, 0.95-0.99). The limits of agreement were from -9.5 to 7.8 degrees. The fetal head was more elongated in occiput posterior position than in non-occiput posterior positions in the second stage of labor. CONCLUSION: We present a novel method of examining fetal head descent by assessing the proximal part of the fetal skull with transabdominal ultrasound. The correlation with transperineal ultrasound measurements was strong, especially early in labor. The fetal head was elongated in the occiput posterior position during the second stage of labor.

Dynamic Evolution of Euchromatic Satellites on the X Chromosome in Drosophila melanogaster and the simulans Clade.

Satellite DNAs (satDNAs) are among the most dynamically evolving components of eukaryotic genomes and play important roles in genome regulation, genome evolution, and speciation. Despite their abundance and functional impact, we know little about the evolutionary dynamics and molecular mechanisms that shape satDNA distributions in genomes. Here, we use high-quality genome assemblies to study the evolutionary dynamics of two complex satDNAs, Rsp-like and 1.688 g/cm3, in Drosophila melanogaster and its three nearest relatives in the simulans clade. We show that large blocks of these repeats are highly dynamic in the heterochromatin, where their genomic location varies across species. We discovered that small blocks of satDNA that are abundant in X chromosome euchromatin are similarly dynamic, with repeats changing in abundance, location, and composition among species. We detail the proliferation of a rare satellite (Rsp-like) across the X chromosome in D. simulans and D. mauritiana. Rsp-like spread by inserting into existing clusters of the older, more abundant 1.688 satellite, in events likely facilitated by microhomology-mediated repair pathways. We show that Rsp-like is abundant on extrachromosomal circular DNA in D. simulans, which may have contributed to its dynamic evolution. Intralocus satDNA expansions via unequal exchange and the movement of higher order repeats also contribute to the fluidity of the repeat landscape. We find evidence that euchromatic satDNA repeats experience cycles of proliferation and diversification somewhat analogous to bursts of transposable element proliferation. Our study lays a foundation for mechanistic studies of satDNA proliferation and the functional and evolutionary consequences of satDNA movement.

Predicting cesarean delivery for failure to progress as an outcome of labor induction in term singleton pregnancy.

BACKGROUND: Induction of labor is one of the most common interventions in modern obstetrics, and its frequency is expected to continue to increase. There is inconsistency as to how failed induction of labor is defined; however, the majority of studies define success as the achievement of vaginal delivery. Induction of labor in nulliparous women poses an additional challenge with a 15% to 20% incidence of failure, ending in emergency operative deliveries. The Bishop score has been traditionally used before decisions for induction of labor. Nonetheless, it is subjective and prone to marked interobserver variation. Several studies have been conducted to find alternative predictors, yet a reliable, objective method still remains to be introduced and validated. Hence, there is still a need for the development of new predictive tools to facilitate informed decision making, optimization of resources, and minimization of potential risks of failure. Furthermore, a peripartum transperineal ultrasound scan has been proven to provide objective, noninvasive assessment of labor. OBJECTIVE: This study aimed to assess the feasibility of developing and validating an objective and reproducible model for the prediction of cesarean delivery for failure to progress as an outcome of labor induction in term singleton pregnancies. STUDY DESIGN: This was a prospective observational cohort study conducted in Cairo University Hospitals and University of Bologna Hospitals between November 2018 and November 2019. We recruited 382 primigravidae with singleton term pregnancies in cephalic presentation. All patients had baseline Bishop scoring together with various transabdominal and transperineal ultrasound assessments of the fetus, maternal cervix, and pelvic floor. The managing obstetricians were blinded to the ultrasound scan findings. The method and indication of induction of labor, the total duration of stages of labor, mode of birth, and neonatal outcomes were all recorded. Women who had operative delivery for fetal distress or indications other than failure to progress in labor were excluded from the final analysis, leaving a total of 344 participants who were randomly divided into 243 and 101 pregnancies that constituted the model development and cross-validation groups, respectively. RESULTS: It was possible to perform transabdominal and transperineal scans and assess all the required parameters on all study participants. Univariate and multivariate analyses were used for selection of potential predictors and model fitting. The independent predictive variables for cesarean delivery included maternal age (odds ratio, 1.12; P=.003), cervical length (odds ratio, 1.08; P=.04), angle of progression at rest (odds ratio, 0.9; P=.001), and occiput posterior position (odds ratio, 5.7; P=.006). We tested the performance of the prediction model on our cross-validation group. The calculated areas under the curve for the ability of the model to predict cesarean delivery were 0.7969 (95% confidence interval, 0.71-0.87) and 0.88 (95% confidence interval, 0.79-0.97) for the developed and validated models, respectively. CONCLUSION: Maternal age and sonographic fetal occiput position, angle of progression at rest, and cervical length before labor induction are very good predictors of induction outcome in nulliparous women at term.

Mechanical Versus Bioprosthetic Valve Replacement in the Tricuspid Valve Position: A Systematic Review and Meta-Analysis.

BACKGROUND: The ideal prosthesis for tricuspid valve replacement (TVR) continues to be debated. There are few published data comparing mechanical and bioprosthetic valves, and all are retrospective studies with relatively small sample sizes. AIM: This study was conducted to compare mechanical and bioprosthetic valves for TVR. METHOD: A literature search of six databases (PubMed, EMBASE, Ovid, ScienceDirect, JSTOR, and Wiley Blackwell's online library) was performed with the keywords "tricuspid valve disease, tricuspid valve replacement and (bioprosthetic or mechanical)". Primary outcomes were hospital mortality, long-term survival, tricuspid valve reoperation, valve failure, thrombosis, and thrombo-embolism. Risk ratio (RR) was used to compare dichotomous parameters and time-to-event outcomes. "Survival and re-interventions" were pooled using a meta-analysis of hazard ratios (HR). Publication bias was accessed using a funnel plot. RESULTS: A total of 23 retrospective studies involving 945 mechanical and 1,332 biological tricuspid prostheses were included. The studies were published between January 2002 and September 2019. Hospital mortality (30-day mortality) did not differ between groups (RR, 0.83; 95% confidence interval [CI], 0.66-1.05; p=0.12). Long-term survival was evaluated in 15 studies, and it was not significantly different between patients with mechanical compared with those with bioprosthetic valves (pooled HR, 0.97; 95% CI, 0.61-1.54; p=0.88). Freedom from tricuspid valve reoperation was assessed in eight studies, and no difference was found between the groups (pooled HR, 1.03; 95% CI, 0.63-1.69; p=0.89). Valve failure in the 5-year postoperative period was evaluated by seven studies, and there was no statistically significant difference between the two groups (pooled RR, 1.33; 95% CI, 0.42-4.27; p=0.63). CONCLUSIONS: The results of this meta-analysis suggest an equal risk of 30-day and late mortality, reoperation, and 5-year valve failure in patients with mechanical versus biological TVR. The choice of the prosthesis in the tricuspid position should depend mainly on the patient's risk factors and no superiority of one prosthesis over the other in this position.

Contraction of the levator ani muscle during Valsalva maneuver (coactivation) is associated with a longer active second stage of labor in nulliparous women undergoing induction of labor.

BACKGROUND: The Valsalva maneuver is normally accompanied by relaxation of the levator ani muscle, which stretches around the presenting part, but in some women the maneuver is accompanied by levator ani muscle contraction, which is referred to as levator ani muscle coactivation. The effect of such coactivation on labor outcome in women undergoing induction of labor has not been previously assessed. OBJECTIVE: The aim of the study was to assess the effect of levator ani muscle coactivation on labor outcome, in particular on the duration of the second and active second stage of labor, in nulliparous women undergoing induction of labor. STUDY DESIGN: Transperineal ultrasound was used to measure the anteroposterior diameter of the levator hiatus, both at rest and at maximum Valsalva maneuver, in a group of nulliparous women undergoing induction of labor in 2 tertiary-level university hospitals. The correlation between anteroposterior diameter of the levator hiatus values and levator ani muscle coactivation with the mode of delivery and various labor durations was assessed. RESULTS: In total, 138 women were included in the analysis. Larger anteroposterior diameter of the levator hiatus at Valsalva was associated with a shorter second stage (r = -0.230, P = .021) and active second stage (r = -0.338, P = .001) of labor. Women with levator ani muscle coactivation had a significantly longer active second stage duration (60 ± 56 vs 28 ± 16 minutes, P < .001). Cox regression analysis, adjusted for maternal age and epidural analgesia, demonstrated an independent significant correlation between levator ani muscle coactivation and a longer active second stage of labor (hazard ratio, 2.085; 95% confidence interval, 1.158-3.752; P = .014). There was no significant difference between women who underwent operative delivery (n = 46) when compared with the spontaneous vaginal delivery group (n = 92) as regards anteroposterior diameter of the levator hiatus at rest and at Valsalva maneuver, nor in the prevalence of levator ani muscle coactivation (10/46 vs 15/92; P = .49). CONCLUSION: Levator ani coactivation is associated with a longer active second stage of labor.

Fetal heart examination at the time of 13 weeks scan: a 5 years' prospective study.

Objective To evaluate our ability in classifying the fetal heart as normal or abnormal during the 1st trimester scan through fetal cardiac examination and determining the best time for this examination. Methods This was a prospective study performed on 3240 pregnant women to examine the fetal heart. Four chambers view and ventricular outflow tracts were mainly examined during the scan. We used grayscale and color mapping in the diagnosis. Color Doppler was used if additional information was needed, and all patients were rescanned during the 2nd trimester to confirm or negate our diagnosis. Results The cardiac findings were normal at both scans in 3108 pregnancies. The same cardiac abnormality was detected at both scans in 79 cases. In 36 cases there was false-positive diagnosis at the early scan; in 20 of these cases, there were mildly abnormal functional findings early in pregnancy with no abnormality found later. In 17 fetuses, there was discordance between the early and later diagnosis due to missed or incorrect diagnoses. The best time to do fetal heart examination during 1st trimester is between 13 and 13 + 6 weeks. Conclusion A high degree of accuracy in the identification of congenital heart disease (CHD) can be achieved by a 1st trimester fetal echocardiography.

Three-dimensional sonohysterography compared with vaginoscopic hysteroscopy for evaluation of the uterine cavity in patients with recurrent implantation failure in in vitro fertilization cycles.

STUDY OBJECTIVE: To estimate the degree of agreement between 3-dimensional sonohysterography (3D-SHG) and vaginoscopic hysteroscopy (VH) in detection of uterine cavity abnormalities in patients with recurrent implantation failure in in vitro fertilization cycles. DESIGN: Comparative observational cross-sectional study (Canadian Task Force classification II-1). SETTING: Private assisted-conception unit. PATIENTS: One hundred forty-three patients with a history of at least 2 previous implantation failures despite transfer of good quality embryos in assisted-conception cycles. INTERVENTIONS: 3D-SHG was followed by VH. The Cohen κ for interrater agreement was calculated for the level of agreement between the 2 diagnostic procedures. Procedure time in seconds was recorded for both procedures. Patients were asked to rate their degree of discomfort or pain during both procedures using a visual analog scale. MEASUREMENTS AND MAIN RESULTS: There was a substantial degree of concordance between 3D-SHG and VH (κ = 0.77; 95% confidence interval, 0.6-0.84). The median procedure time for 3D-SHG was 296 seconds (range, 231-327 seconds), and for VH was 315 seconds (range, 232-361 seconds), and the difference was statistically significant (p =.02). The visual analog scale pain scores also showed that 3D-SHG, with a median pain score of 2.1 (range, 1-3) was better tolerated than VH, with a median pain score of 2.9 (range, 2-4) (p < .001). CONCLUSION: Our results show that there is a substantial degree of concordance between 3D-SHG and VH in diagnosing uterine cavity anomalies. We also found that 3D-SHG took significantly less time and induced less patient discomfort than did VH. We recommend that 3D-SHG should be the method of first choice for outpatient evaluation of the uterine cavity.

The value of three-dimensional ultrasound in identifying Mullerian anomalies at risk of adverse pregnancy outcomes.

OBJECTIVE: To examine the reliability of three-dimensional ultrasound (3 D-US) in the differentiation between subseptate and arcuate uteri, due to the different associated pregnancy outcomes; refine the existing 3 D-US parameters and evaluate the concordance between 3 D-US and MRI in diagnosing these anomalies. STUDY DESIGN: This was a prospective cohort study of 455 women suspected of having a Mullerian anomaly. The diagnosis of subseptate, bicornuate or arcuate uterus was made by 3 D-US in 55 women. Two independent examiners manipulated the 3 D-US volume datasets and recorded the internal intercornual distance, indentation length, indentation tip angle, and myometrial wall thickness in the coronal plane of the uterus. Subsequently, 48 women underwent MRI which was used as the reference test for diagnosis. We calculated the degree of correlation between the two ultrasound assessors' 3 D-US measurements using interclass correlation coefficient and as well as a Bland-Altman plot. The mean values of the four parameters were used to create receiver operating characteristic curves for determining the best cutoff values for differentiation between subseptate and arcuate uterui. We used the Cohen's Kappa test to measure the level of agreement between 3 D-US and MRI. RESULTS: There was good interobserver agreement between the two 3 D-US assessors for all four parameters. There was a substantial level of agreement between 3 D-US and MRI in differentiating between bicornuate, subseptate and arcuate uteri with a kappa value of 0.727 (95% CI 0.443-0.856). Distinction between subseptate and arcuate uterus was improved when using an indentation length ≥12.5 mm (AUC 0.99) and indentation tip angle ≤89.25 degrees (AUC 0.97) as cutoffs for diagnosis but not the internal intercornual distance or myometrial wall thickness. CONCLUSION: 3 D-US evaluation of the coronal view of the uterus can be relied upon to make a noninvasive, accurate differentiation between subseptate and arcuate uteri. The fundal indentation length and indentation tip angle cut offs of ≥12.5 mm and ≤88 mm, respectively were found to be most accurate for distinction. Thus, allowing for individualizing pre-pregnancy management plans and patient-informed healthcare choices.HighlightsThere are no agreed upon criteria for differentiating arcuate from subseptate uteri. Such differentiation is critical for counseling and management due to the substantial difference in pregnancy outcome.We aimed to propose cut off values for ultrasound measurements standardized against MRI diagnostic criteria for accurate differentiation between arcuate and subseptate uteri.We demonstrated substantial agreement between 3D-US and MRI in differentiating between bicornuate, subseptate and arcuate uteri.3D-US evaluation of the coronal view of the uterus is reliable to make an accurate differentiation between subseptate and arcuate uteri.Using the indentation length ≥12.5 mm and indentation tip angle ≤89.25 degrees as parameters to be measured on the coronal view by 3D-US increases its diagnostic accuracy for distinction between arcuate and subseptate uteri.

RepeatProfiler: A pipeline for visualization and comparative analysis of repetitive DNA profiles.

Study of repetitive DNA elements in model organisms highlights the role of repetitive elements (REs) in many processes that drive genome evolution and phenotypic change. Because REs are much more dynamic than single-copy DNA, repetitive sequences can reveal signals of evolutionary history over short time scales that may not be evident in sequences from slower-evolving genomic regions. Many tools for studying REs are directed toward organisms with existing genomic resources, including genome assemblies and repeat libraries. However, signals in repeat variation may prove especially valuable in disentangling evolutionary histories in diverse non-model groups, for which genomic resources are limited. Here, we introduce RepeatProfiler, a tool for generating, visualizing, and comparing repetitive element DNA profiles from low-coverage, short-read sequence data. RepeatProfiler automates the generation and visualization of RE coverage depth profiles (RE profiles) and allows for statistical comparison of profile shape across samples. In addition, RepeatProfiler facilitates comparison of profiles by extracting signal from sequence variants across profiles which can then be analysed as molecular morphological characters using phylogenetic analysis. We validate RepeatProfiler with data sets from ground beetles (Bembidion), flies (Drosophila), and tomatoes (Solanum). We highlight the potential of RE profiles as a high-resolution data source for studies in species delimitation, comparative genomics, and repeat biology.

Reliability of transperineal ultrasound for the assessment of the angle of progression in labor using parasagittal approach versus midsagittal approach.

OBJECTIVE: To assess the inter-method agreement between midsagittal (msAoP) and parasagittal (psAoP) measurements of the angle of progression (AoP) during labor. In addition, we aimed to evaluate the correlation between AoP measurements by both midsagittal and parasagittal approaches with the mode of delivery. METHODS: We recruited a nonconsecutive series of women in active labor with a singleton uncomplicated term pregnancy with fetuses in vertex presentation. Women underwent transperineal ultrasound in the absence of uterine contractions or maternal pushing to measure both msAoP and psAoP. The inter-method agreement between the two acquisitions was then assessed. Lastly, both measurements were compared between women who had a vaginal delivery versus those who underwent cesarean section (CS). RESULTS: Overall, 151 women were included in the study. We found an excellent agreement between msAoP and psAoP (ICC 0.935; 95% CI 0.912-0.953, p < .001). On the other hand, psAoP overestimated the measurements in comparison with msAoP (101.2 ± 15.6 versus 98.2 ± 16.0, p < .001). There was a significant correlation between both methods of AoP assessment and duration of the active second stage of labor and AoP measured by either method was significantly wider in patients who delivered vaginally compared to those who had a CS. CONCLUSIONS: Our data showed a significant difference in the measured angle between the psAoP and the originally described msAoP. The automated measurements of AoP that have been introduced are designed using the parasagittal visualization of the more echogenic pubic arch, rather than the hypoechogenic pubic symphysis. We think that in the light of our data, care should be taken before applying data from midsagittal measurement in centers using the parasagittal automated approach.