Placental Pathologic Conditions Research Articles

Adenomyosis in Pregnancy: Diagnostic Pearls and Pitfalls.

Adenomyosis is a common benign uterine disorder in which ectopic endometrial glands extend into the myometrium. Adenomyosis is increasingly diagnosed in young women, affecting 20%-35% of women of reproductive age. Features of adenomyosis can be seen with either US or MRI, especially with newer imaging technology. With advances in reproductive endocrinology as well as a trend toward later maternal age, adenomyosis is increasingly noted during pregnancy, often while performing imaging for other reasons. Hormonal changes during pregnancy alter the appearance of adenomyosis, which includes diffuse, focal, and cystic adenomyosis. Recognizing these imaging changes in pregnancy proves essential for accurately diagnosing adenomyosis as a benign condition, as it mimics serious placental and myometrial abnormalities. Using a lower-frequency US transducer or MRI can be helpful in distinguishing among these entities. Describing the location of adenomyosis in relationship to the site of placentation is also important. Diagnosing adenomyosis is crucial because it can be associated with poor pregnancy outcomes, including spontaneous abortion, preterm birth, and fetal growth restriction. Adenomyosis is also a risk factor for preeclampsia. Intramural ectopic pregnancy is a rare but serious condition that can mimic cystic adenomyosis, and comparison with prepregnancy images can help differentiate the two conditions. The authors review the unique imaging characteristics of adenomyosis in pregnancy, focusing on accurate diagnosis of an underrecognized benign condition that can mimic myometrial and placental pathologic conditions.©RSNA, 2021.

Correlation of Placental Magnetic Resonance Imaging With Histopathologic Diagnosis: Detection of Aberrations in Structure and Water Diffusivity.

Noninvasive methods to identify placental pathologic conditions are being sought in order to recognize these conditions at an earlier stage leading to improved clinical interventions and perinatal outcomes. The objective of this study was to examine fixed tissue slices of placenta by T2- and diffusion-weighted magnetic resonance imaging (MRI) and correlate the images with placental pathologic findings defined by routine gross and histologic examination. Four formalin-fixed placentas with significant placental pathology (maternal vascular malperfusion, chronic villitis of unknown etiology, and massive perivillous fibrin deposition) and 2 histologically normal placentas were evaluated by high-resolution MRI. Representative placental slices were selected (2 cm long and 10 mm wide) and rehydrated. Imaging was performed on a Bruker Avance 14.1 T microimager. Diffusion-weighted images were acquired from 16 slices using slice thickness 0.5 mm and in-plane resolution approximately 100 µm × 100 µm. T2 maps were obtained from the same slices. T2 relaxation time and apparent diffusion coefficient (ADC) were acquired from representative regions of interest and compared between normal and diseased placentas. In T2- and diffusion-weighted images, the placental microstructure differed subjectively between diseased and normal placentas. Furthermore, diseased placentas showed statistically significantly longer mean T2 relaxation times and generally higher mean ADC. Diffusion- and T2-weighted MRI can potentially be used to detect significant placental pathology by using T2 relaxation time and ADC as markers of altered placental microstructure.

Sonography of placental abnormalities: a pictorial review.

Often overlooked during routine ultrasound evaluation of a normal pregnancy, the placenta forms the biologic interface between the mother and fetus and is critical to fetal growth and development. Malformations in development, positioning, and vascularity can have profound implications for both maternal and fetal well-being. As such, a judicious inspection of the placenta is warranted as an integral part of every screening or emergent prenatal ultrasound. Herein, we present a pictorial review of a variety of placental pathologic conditions including abnormalities in positioning, adherence, vascularity, and hemorrhage as well as potential peri-placental masses and gestational trophoblastic disease, all of which are readily encountered in a busy emergency radiology practice.

The preterm birth syndrome: a prototype phenotypic classification

Preterm birth is a syndrome with many causes and phenotypes. We propose a classification that is based on clinical phenotypes that are defined by ≥ 1 characteristics of the mother, the fetus, the placenta, the signs of parturition, and the pathway to delivery. Risk factors and mode of delivery are not included. There are 5 components in a preterm birth phenotype: (1) maternal conditions that are present before presentation for delivery, (2) fetal conditions that are present before presentation for delivery, (3) placental pathologic conditions, (4) signs of the initiation of parturition, and (5) the pathway to delivery. This system does not force any preterm birth into a predefined phenotype and allows all relevant conditions to become part of the phenotype. Needed data can be collected from the medical records to classify every preterm birth. The classification system will improve understanding of the cause and improve surveillance across populations.

Decidual CD8+CD28− T cells express CD103 but not perforin

Maternal lymphocytes at the fetal–maternal interface play a key role in the immune acceptance of the allogeneic fetus. Decidual NK cells have shown to contain immune modulatory properties and may facilitate fetal trophoblast invasion into maternal tissue. More recently, CD4+CD25 brightFOXP3+ Treg cells have been shown to be concentrated in decidual tissue and to be able to suppress both fetus-specific and nonspecific responses. However CD8+ T cells form the largest fraction of T cells at the fetal–maternal interface and are the main candidates to recognize and respond to fetal–maternal HLA differences. So far limited data are available on the phenotype and function of decidual CD8+ T cells during pregnancy. Phenotypic analysis of peripheral blood and decidual CD8+ T cells showed the presence of activated CD8+ T cells as well as a population of CD8+CD103+ T cells in decidual tissue. Unlike peripheral CD8+CD28− T cells, decidual CD8+CD28− T cells do not express the cytolytic molecule perforin. The lack of perforin expression may indicate that decidual CD8+ T cells are not able to elicit a cytotoxic response, and supports the hypothesis that decidual CD8+ T cells play a role in local immune regulation. Defects in decidual CD8+ T-cell regulation or differentiation may lead to placental pathologic conditions whereby placental and fetal growth are impaired.

Essai de travail en cas de césarienne antérieure

The aim of this review was to relate the evolution of obstetrical management of delivery in women who had previously undergone cesarean delivery and to search the studies supporting the choice of the mode of delivery.We identified relevant studies through a computer search in the Medline database.After a period from 1980 to 2000 when the vaginal delivery had been increasingly recommended, a growth in the use of the planned cesarean delivery was observed. Recent studies report more evidence that uterine rupture is the result of trial of labor and that adverse perinatal outcomes are associated with uterine rupture. The risk of uterine rupture is increased with labor induction. The use of prostaglandins appears to be implicated in a significant increase of uterine rupture, and subsequently might be contraindicated in this situation. The use of oxytocin induced labor appears to increase the risk of uterine rupture. However, the level of adverse perinatal outcomes is low. The choice of the mode of delivery should take into account the likelihood of a further pregnancy, due to the increased risk of placental pathologic conditions depending on the number of repeated cesarean sections.An optimal decision for the mode of delivery should be shared with the pregnant women and all these factors should be taken into consideration.

Vaginal birth after cesarean section: Trial of labor or repeat cesarean section? A decision analysis

Objective The risk of perinatal death associated with labor after previous cesarean section appears higher than with a repeated cesarean section. On the other hand, repeated cesarean sections are associated with increased maternal morbidity and mortality from placental pathologic conditions (previa or accreta) on subsequent pregnancies. The study was undertaken to analyze the decision for a trial of labor or a repeated cesarean section, after a prior cesarean section, with varying desire for an additional pregnancy. Study design A model was formulated using a decision tree, based on the reported risks of the two approaches. Sensitivity analysis was performed over a variety of probabilities (eg, chance of uterine rupture or neonatal death, chance of rescue cesarean section, desire for an additional pregnancy) and utilities (eg, use of hysterectomy or neonatal death). Results The model favors a trial of labor if it has a chance of success of 50% or above and if the wish for additional pregnancies after a cesarean section is estimated at near 10% to 20% or above because the delayed risks from a repeated cesarean section are greater than its immediate benefit. The model was robust over a wide range of assumptions. Conclusion An optimal decision for a trial of labor or a repeated cesarean section is substantially determined by the wish for future pregnancies. The default option of a repeated cesarean section is not directly applicable in populations in which family planning often extends over two children.

Placental pathology in systemic lupus erythematosus: A prospective study

OBJECTIVES: Systemic lupus erythematosus and antiphospholipid antibody, often identified in patients with systemic lupus erythematosus, are associated with poor pregnancy outcome. This study distinguishes between the effect of each of these factors on gestational outcome and placental pathologic conditions in pregnant patients with systemic lupus erythematosus. STUDY DESIGN: Thirty-seven pregnancies and 40 placentas from 33 women with systemic lupus erythematosus were studied prospectively. RESULTS: Systemic lupus erythematosus alone, but not systemic lupus erythematosus activity, was associated with increased spontaneous abortions, preterm gestations, and fetal growth restriction. Placental correlates were ischemic-hypoxic change, decidual vasculopathy, decidual and fetal thrombi, chronic villitis, and decreased placental weight. Extensive infarction and fetal death were important antiphospholipid antibody–related findings. CONCLUSIONS: Decidual vasculopathy/coagulopathy appears to mediate the antiphospholipid antibody–related and much of the systemic lupus erythematosus–related deleterious effect on the placenta and gestational outcome. The presence of antiphospholipid antibody largely, but not invariably, predicts fetal death. Antiphospholipid antibody–independent chronic villitis may represent a second mechanism of systemic lupus erythematosus–related change. (Am J Obstet Gynecol 1998;179:226-34.)

Stillbirth evaluation: What tests are needed?

OBJECTIVE: We sought to investigate what aspects of the stillbirth evaluation are considered to be essential and what tests can potentially be eliminated. STUDY DESIGN: A retrospective analysis of 745 stillbirths occurring from January 1990 to December 1994 was conducted. A stillbirth was defined by an estimated gestational age >20 weeks' gestational age or fetal weight >500 gm. We attempted to arrive at an apparent cause for each stillbirth after evaluation of genetic or chromosomal abnormalities, obstetric history, maternal medical illnesses, laboratory tests, autopsy findings, and placental pathologic conditions. RESULTS: We found that the most important aspects of stillbirth evaluation were placental pathologic conditions and autopsy. When the placenta was examined, a significant abnormality was detected in 30% (160 of 529) of the cases. When autopsy was performed, only 31% of fetal deaths (142 of 462) were unexplained; however, when no autopsy was performed, 44% (125 of 283) were unexplained ( p = 0.0002). The following laboratory evaluations that were routinely performed were found to yield little definitive information: antinuclear antibody testing, Kleihauer-Betke test, and screening for congenital infections (toxoplasmosis, other viruses, rubella, cytomegalovirus, and herpes simplex virus). Overall, 36% (267 of 745) of stillbirths still remained unexplained despite a thorough evaluation in most cases. CONCLUSION: The causes of stillbirth are many and varied, with a large proportion having no obvious cause. As this study demonstrates, certain laboratory tests can be eliminated in the workup of fetal death. In the evaluation of stillbirth a complete systematic method that incorporates placental pathologic conditions, as well as autopsy findings, should prove to be beneficial. (Am J Obstet Gynecol 1998;178:1121-5.)

Relatively reduced values of plasma alpha-fetoprotein at early second trimester of pregnancies with hypertensive disorders.

Hypertensive disorders during pregnancy implicate placental pathologic conditions, which may interfere with the normal passage of alpha-fetoprotein (AFP) to the maternal blood. We compared the levels of maternal serum (MS) in early second trimester of pregnancies complicated by hypertensive disorders with those of matched controls. The distribution in the study group of MS-AFP multiple of median values was significantly different from the distribution in the control group. Moreover, up to multiple of the median 1.00, the number of hypertensive patients was larger than the number of normotensive pregnant women. The mean level of multiples of the median in the study group was significantly lower than that of the control group (p value = 0.003, 95% confidence interval: -0.30, -0.05). In the analysis of the distinct types of hypertension, the difference remained significant for 85 women in the moderate hypertension subgroup (p value = 0.032, confidence interval: -0.34, -0.02) and was not significant for the severe hypertension subgroup of 22 women (p value = 0.24, 95% confidence interval: -0.57, 0.15) and chronic hypertension subgroup of women (p value = 0.52, 95% confidence interval: -0.44, 0.00). The trend was consistent in all the subgroups. Relatively low values of maternal serum AFP at early second trimester of pregnancies with hypertensive disorders may be a result of placental pathologic involvement and can help in the identification of the women at risk.

Sonographic Evaluation of Growth Discordance and Chorionicity in Twin Gestation

Ninety-four twin gestations had serial ultrasound examinations for evaluation of fetal growth, with special attention to prediction of weight discordance and chorionicity. Fetal weight estimations were made a mean of 3.2 days before birth and then compared to actual birthweights. The average error in intertwin discordance prediction was 1 +/- 9%. In 56 patients ultrasonic detection of membrane thickness was compared with placental pathologic conditions. If a membrane was seen between twins, it was confirmed by placental pathologic study in all cases. No membrane was seen in four twin pairs, but only one of these actually had monochorionic monoamniotic membranes. The three cases with false-positive diagnoses of monoamniotic twin gestation were initially seen late in pregnancy. If clinical decisions in twin gestations are based on ultrasound determination of discordance and chorionicity, the level of accuracy demonstrated by these data must be considered.