Does the presence of placental basal plate myometrial fibres increase the risk of subsequent morbidly adherent placenta: a case-control study.

OBJECTIVE: Antenatal diagnosis of morbidly adherent placenta has been shown to improve outcomes, but existing predictors lack sensitivity. Our objective was to determine whether the presence of myometrial fibres attached to the placental basal plate (BPMYO) in an antecedent pregnancy is associated with subsequent morbidly adherent placenta. DESIGN: A case-control study. SETTING: Departments of Obstetrics and Gynecology and Pathology, Northwestern University, Chicago, IL, USA. SAMPLE: Women who had at least two pregnancies with placental pathological evaluation. METHODS: Cases were defined as women with evidence of morbidly adherent placenta (both clinically and pathologically) in their most recent pregnancy whereas women without evidence of morbidly adherent placenta served as controls. Pathological specimens of placentas from previous pregnancies were evaluated for BPMYO. The presence of BPMYO on a previous placenta was evaluated to determine whether it could be used to improve the antenatal diagnosis of morbidly adherent placenta. RESULTS: Of the 25 cases of morbidly adherent placenta, 19 (76%) had BPMYO present on their previous placenta compared with 41 (41%) of controls (odds ratio 4.8, 95% CI 1.8-13.0). Adding BPMYO to a regression including other risk factors for morbidly adherent placenta (i.e. maternal age, number of previous caesarean sections, placenta praevia, previous multiple gestation, any previous curettage, and ultrasonographic suspicion of placenta accreta) significantly improved the sensitivity of antenatal diagnosis of morbidly adherent placenta (61% versus 39%, P < 0.001) without a change in specificity (97% versus 97%, P = 1.00). CONCLUSION: BPMYO on previous placental pathology is associated with an increased risk of morbidly adherent placenta in a subsequent pregnancy. These findings may shed light on the pathophysiology of accreta and inform future research on predictors of accreta. TWEETABLE ABSTRACT: Previous basal plate myometrium improves the ability to detect subsequent morbidly adherent placenta.

Stillbirth: Genome-wide copy number variation profiling in archived placental umbilical cord samples with pathologic and clinical correlation.

INTRODUCTION: Stillbirth remains a devastating health issue with 26,000 stillbirths occurring annually in the United States. Formalin-fixed, paraffin-embedded (FFPE) umbilical cord samples are available for many stillbirths. Our aim was to validate the use of these samples in identifying genetic variations in stillbirth through microarray analysis. METHODS: This is a retrospective case-control study from a single institution of stillbirths ≥ 23 weeks gestational age and control liveborn infants. Fetal genomic DNA was extracted from FFPE umbilical cord samples of stillborn and control placentas, and genotyping was performed using the Illumina HumanOmniExpresss-12v1 Beadchip. Array results were verified with qPCR. RESULTS: 31 case-specific CNVs (17 deletions and 14 amplifications) with an average size of 294 kb for amplifications and 74 kb for deletions were identified among 94 FFPE samples (86 cases; 8 controls). In total 38 (44%) of the stillbirth samples had a CNV detected. Validation of a subset of microarray findings with qPCR confirmed deletions on 1p (2 cases), 11q (4 cases) and amplifications on 18 (1 case). Placental underperfusion changes were seen in stillborns with deletions on 1p, a region containing complement regulatory genes which have been shown to play a role in preeclampsia. DISCUSSION: This study validated the use of archived FFPE umbilical cord samples for genome-wide copy number profiling in stillbirths, and demonstrates specific CNV deletions and amplifications. Microarray analysis in an expanded cohort of stillbirth FFPE samples has the potential to identify biomarkers involved in stillbirth pathogenesis.

A Maximum Likelihood Solution To The Errors In Variables And Errors In Equations Model.

This article provides a maximum likelihood estimation procedure for a linear model with errors in variables. Warren, et al, provide a least squares procedure for the same problem but which may be shown to be a special case of the more general approach suggested here. Also unlike the least squares approach, this formulation permits tests of the independence of measurement errors as well as the equality of measurement units. The importance of testing these assumptions is related to various definitions as well as estimation methods for reliability.

Between, Within, and Total Group Factor Analyses of Student Ratings of Instruction.

The purpose of this study was to compare the factor structures of student ratings of instruction resulting from total group, between group, and within group analyses. Six factors obtained from responses by 9700 students to 31 items were used to approximate the between group covariance matrix based on 43'7 classroom means and the pooled within classroom covariance matrix. A good approximation to both the between and within group covariance matrices was obtained.