PLACENTAL CALCIFICATION A STUDY OF 3,025 SINGLETON AND MULTIPLE PREGNANCIES

Placental Histopathology in COVID-19-Positive Mothers

The placenta is a captivating multifunctional organ of fetal origin and plays an essential role during pregnancy by intimately connecting mother and baby. This study explicates placental pathology and information about 25 placentas collected from the mothers infected with novel coronavirus (SARS-COV-2). So far, congenital transmission of SARS-CoV-2 seems to be remarkably uncommon in spite of many cases of COVID-19 during pregnancy. Out of the 25 placental tissue samples collected, none has shown gene expression of SARS-CoV-2 when confirmed by RT-PCR. At the same time, nasal and throat swab samples collected from newborns of SARS-CoV-2-positive mothers correspondingly tested negative by RT-PCR. The shielding properties of placental barriers against viral infections from mothers to newborns remains a mystery. Major histopathological findings have been recorded as choriodecidual tissue with necrosis, intramural fibrin deposition, chorionic villi with fibrosis, and calcification. Moreover, although recent findings are insufficient to prove direct placental transmission of COVID-19, the abundance of angiotensin-converting enzymes-2 (ACE-2) on the placental surface could potentially contribute to unpleasant outcomes during pregnancy as SARSCoV-2 gains access to human cells via ACE-2. Finally, the significance of these findings is vague and needs further study.

Pictorial review of the postmortem computed tomography in neonaticide cases

Neonaticide is defined by the deliberate killing or homicide of a child within 24 h of its birth. In this context, three fundamental questions are generally asked of the forensic pathologist: what is the cause of death of the neonate? Was the child viable (i.e., what is the gestational age of the neonate)? Finally, was the neonate stillborn or liveborn?Postmortem imaging can help answer these questions by conducting (1) a complete lesional analysis of the body and the placenta, (2) an estimation of the gestational age by measuring the lengths of the diaphyseal long bones, and (3) an analysis of the aeration of the lungs and intestines. Using the details of 18 cases, we illustrate aspects of neonaticide cases in postmortem computed tomography (PMCT), offering detailed examples of notable postmortem changes and abnormalities, especially in the analysis of the pulmonary parenchyma. This article presents a useful iconography for the radiologist confronted with this rare yet complex forensic situation.

Spontaneous Abortion and Chikungunya Infection: Pathological Findings

Intrauterine transmission of the Chikungunya virus (CHIKV) during early pregnancy has rarely been reported, although vertical transmission has been observed in newborns. Here, we report four cases of spontaneous abortion in women who became infected with CHIKV between the 11th and 17th weeks of pregnancy. Laboratorial confirmation of the infection was conducted by RT-PCR on a urine sample for one case, and the other three were by detection of IgM anti-CHIKV antibodies. Hematoxylin and eosin (H&E) staining and an electron microscopy assay allowed us to find histopathological, such as inflammatory infiltrate in the decidua and chorionic villi, as well as areas of calcification, edema and the deposition of fibrinoid material, and ultrastructural changes, such as mitochondria with fewer cristae and ruptured membranes, endoplasmic reticulum with dilated cisterns, dispersed chromatin in the nuclei and the presence of an apoptotic body in case 1. In addition, by immunohistochemistry (IHC), we found a positivity for the anti-CHIKV antibody in cells of the endometrial glands, decidual cells, syncytiotrophoblasts, cytotrophoblasts, Hofbauer cells and decidual macrophages. Electron microscopy also helped in identifying virus-like particles in the aborted material with a diameter of 40–50 nm, which was consistent with the size of CHIKV particles in the literature. Our findings in this study suggest early maternal fetal transmission, adding more evidence on the role of CHIKV in fetal death.

Pathological Mineralization: The Potential of Mineralomics

Pathological mineralization has been reported countless times in the literature and is a well-known phenomenon in the medical field for its connections to a wide range of diseases, including cancer, cardiovascular, and neurodegenerative diseases. The minerals involved in calcification, however, have not been directly studied as extensively as the organic components of each of the pathologies. These have been studied in isolation and, for most of them, physicochemical properties are hitherto not fully known. In a parallel development, materials science methods such as electron microscopy, spectroscopy, thermal analysis, and others have been used in biology mainly for the study of hard tissues and biomaterials and have only recently been incorporated in the study of other biological systems. This review connects a range of soft tissue diseases, including breast cancer, age-related macular degeneration, aortic valve stenosis, kidney stone diseases, and Fahr’s syndrome, all of which have been associated with mineralization processes. Furthermore, it describes how physicochemical material characterization methods have been used to provide new information on such pathologies. Here, we focus on diseases that are associated with calcium-composed minerals to discuss how understanding the properties of these minerals can provide new insights on their origins, considering that different conditions and biological features are required for each type of mineral to be formed. We show that mineralomics, or the study of the properties and roles of minerals, can provide information which will help to improve prevention methods against pathological mineral build-up, which in the cases of most of the diseases mentioned in this review, will ultimately lead to new prevention or treatment methods for the diseases. Importantly, this review aims to highlight that chemical composition alone cannot fully support conclusions drawn on the nature of these minerals.

Placental Vascular Calcification and Cardiovascular Health: It Is Time to Determine How Much of Maternal and Offspring Health Is Written in Stone

Vascular calcification is the deposition of calcium phosphate minerals in vascular tissue. Vascular calcification occurs by both active and passive processes. Extent and tissue-specific patterns of vascular calcification are predictors of cardiovascular morbidity and mortality. The placenta is a highly vascularized organ with specialized vasculature that mediates communication between two circulatory systems. At delivery the placenta often contains calcified tissue and calcification can be considered a marker of viral infection, but the mechanisms, histoanatomical specificity, and pathophysiological significance of placental calcification are poorly understood. In this review, we outline the current understanding of vascular calcification mechanisms, biomedical consequences, and therapeutic interventions in the context of histoanatomical types. We summarize available placental calcification data and clinical grading systems for placental calcification. We report on studies that have examined the association between placental calcification and acute adverse maternal and fetal outcomes. We then review the intersection between placental dysfunction and long-term cardiovascular health, including subsequent occurrence of maternal vascular calcification. Possible maternal phenotypes and trigger mechanisms that may predispose for calcification and cardiovascular disease are discussed. We go on to highlight the potential diagnostic value of placental calcification. Finally, we suggest avenues of research to evaluate placental calcification as a research model for investigating the relationship between placental dysfunction and cardiovascular health, as well as a biomarker for placental dysfunction, adverse clinical outcomes, and increased risk of subsequent maternal and offspring cardiovascular events.

To ignore or not to ignore placental calcifications on prenatal ultrasound: a systematic review and meta-analysis

OBJECTIVE

The human placenta is known to calcify with advancing gestational age, and, in fact, the presence of significant calcifications is one of the components of grade III placenta, typical of late gestation. As such, the presence of significant placental calcifications often prompts obstetric providers to expedite delivery. This practice has been attributed, in part, to the presumed association between grade III placenta and adverse pregnancy outcomes. Such approach, however, can be the source of major anxiety and may lead to unnecessary induction of labor, with its associated predisposition to cesarean delivery as well as a myriad of maternal and neonatal morbidities. The objective of this study was to examine the association between grade III placental calcifications and pregnancy outcomes.

MATERIALS AND METHODS

A systematic review of the literature was performed for studies evaluating the association between grade III placenta and a number of pregnancy outcomes, including labor induction, fetal distress (abnormal fetal heart tracing), low Apgar score (less than 7 at 5 min), need for neonatal resuscitation, admission to the Neonatal Intensive Care Unit, perinatal death, meconium liquor, and low birth weight.

RESULTS

There was a five-fold increase in risk of labor induction with the presence of grade III placenta (OR 5.41; 95% CI 2.98-9.82). There was no association between grade III placenta and the incidence of abnormal fetal heart tracing (OR 1.62; 95% CI 0.94-2.78), low Apgar score of less than 7 at 5 min (OR 1.68; 95% CI 0.84-3.36), need for neonatal resuscitation (OR 1.08; 95% CI 0.67-1.75), and admission to the Neonatal Intensive Care Unit (OR 0.90; 95% CI 0.21-3.74). In turn, the incidence of meconium liquor was higher in the setting of grade III placentae (OR 1.68; 95% CI 1.17-2.39). Similarly, a positive association between grade III placental calcifications and low birth weight (OR 1.63; 95% CI 1.19-2.22) and perinatal death (OR 7.41; 95% CI 4.94-11.09) was identified.

CONCLUSION

The study alerts us to a significant association between grade 3 placental calcifications and labor induction, although it demonstrates that these sonographic findings do not appear to predispose to fetal distress, low Apgar score, need for neonatal resuscitation, or admission to the NICU.

A molecular portrait of maternal sepsis from Byzantine Troy

Pregnancy complications are poorly represented in the archeological record, despite their importance in contemporary and ancient societies. While excavating a Byzantine cemetery in Troy, we discovered calcified abscesses among a woman’s remains. Scanning electron microscopy of the tissue revealed ‘ghost cells’, resulting from dystrophic calcification, which preserved ancient maternal, fetal and bacterial DNA of a severe infection, likely chorioamnionitis. Gardnerella vaginalis and Staphylococcus saprophyticus dominated the abscesses. Phylogenomic analyses of ancient, historical, and contemporary data showed that G. vaginalis Troy fell within contemporary genetic diversity, whereas S. saprophyticus Troy belongs to a lineage that does not appear to be commonly associated with human disease today. We speculate that the ecology of S. saprophyticus infection may have differed in the ancient world as a result of close contacts between humans and domesticated animals. These results highlight the complex and dynamic interactions with our microbial milieu that underlie severe maternal infections.

DOI:http://dx.doi.org/10.7554/eLife.20983.001

Why and how have some bacteria evolved to cause illness in humans? One way to study bacterial evolution is to search for ancient samples of bacteria and use DNA sequencing technology to investigate how modern bacteria have changed from their ancestors. Understanding the evolution process may help researchers to understand how some bacteria become resistant to the antibiotics designed to kill them.

Complications that occur during pregnancy, including bacterial infections, have long been a major cause of death for women. Now, Devault, Mortimer et al. have been able to sequence the DNA of bacteria found in tissue collected from a woman buried 800 years ago in a cemetery in Troy. Some of the woman’s tissues had been well preserved because they had calcified (probably as the result of infection), which preserved their structure in a mineralized layer. Two mineralized “nodules” in the body appear to be the remains of abscesses. Some of the human DNA in the nodules came from a male, suggesting that the woman was pregnant with a boy and that the abscesses formed in placental tissue.

Sequencing the DNA of the bacteria in the abscess allowed Devault, Mortimer et al. to diagnose the woman’s infection, which was caused by two types of bacteria. One species, called Gardnerella vaginalis, is found in modern pregnancy-related infections. The DNA of the ancient samples was similar to that of modern bacteria. The other bacteria species was an ancient form of Staphylococcus saprophyticus, a type of bacteria that causes urinary tract infections. However, the DNA of the ancient S. saprophyticus bacteria is quite different to that of the bacteria found in modern humans. Instead, their DNA sequence appears more similar to forms of the bacteria that infect currently livestock. As humans lived closely with their livestock at the time the woman lived, her infection may be due to a type of bacteria that passed easily between humans and animals.

Overall, the results suggest that the disease-causing properties of bacteria can arise from a wide range of sources. In addition, Devault, Mortimer et al. have demonstrated that certain types of tissue found in archeological remains are a potential gold mine of information about the evolution of bacteria and other microbes found in the human body.

DOI:http://dx.doi.org/10.7554/eLife.20983.002

Positive and negative effects of cellular senescence during female reproductive aging and pregnancy

Cellular senescence is a phenomenon occurring when cells are no longer able to divide even after treatment with growth stimuli. Because senescent cells are typically associated with aging and age-related diseases, cellular senescence is hypothesized to contribute to the age-related decline in reproductive function. However, some data suggest that senescent cells may also be important for normal physiological functions during pregnancy. Herein, we review the positive and negative effects of cellular senescence on female reproductive aging and pregnancy. We discuss how senescent cells accelerate female reproductive aging by promoting the decline in the number of ovarian follicles and increasing complications during pregnancy. We also describe how cellular senescence plays an important role in placental and fetal development as a beneficial process, ensuring proper homeostasis during pregnancy.

Association between placental mineral deposition, villous architecture and fetal aneuploidy

We retrospectively evaluated the relationship between fetal aneuploidy and placental mineral deposits and villous architecture in 2nd trimester placentas of mid-trimester pregnancy terminations for fetal anomaly. Study cases were aneuploid and matched with euploid controls. Six slides per case were histologically evaluated. Our findings showed significantly increased subtrophoblastic mineral depositions in aneuploidy placentas; also, villous architecture changes between study and control cases were significant for multifocal/extensive villous scalloping and syncytial budding. Our conclusion was that placental histological findings of extensive subtrophoblastic mineral deposition, multifocal/extensive villous scalloping and syncytial budding may suggest aneuploidy.

Ultrasound of the placenta: a systematic approach. Part I: Imaging

Diagnostic ultrasound has been in use in clinical obstetrics for close to half-a-century. However, in the literature, examination of the placenta appears to be treated with less attention than the fetus or the pregnant uterus. This is somewhat unexpected, given the obvious major functions this organ performs during the entire pregnancy. Examination of the placenta plays a foremost role in the assessment of normal and abnormal pregnancies. A methodical sonographic evaluation of the placenta should include: location, visual estimation of the size (and, if appearing abnormal, measurement of thickness and/or volume), implantation, morphology, anatomy, as well as a search for anomalies, such as additional lobes and tumors. Additional assessment for multiple gestations consists of examining the intervening membranes (if present). The current review considers the various placental characteristics, as they can be evaluated by ultrasound, and the clinical significance of abnormalities of these features. Numerous and varied pathologies of the placenta can be detected by routine ultrasound. It is incumbent on the clinician performing obstetrical ultrasound to examine the placenta in details and in a methodical fashion because of the far reaching clinical significance and potentially avoidable severe consequences of many of these abnormalities.

Ultrasound Markers of Fetal Infection, Part 2

Up to 1% of all pregnancies have clinically overt intra-amniotic bacterial infections, and an even larger percentage of pregnant women may be affected by silent infections. Although most pregnant women with overt intra-amniotic bacterial infection have experienced prolonged rupture of membranes (PROM), symptomatic and most silent nonviral intra-amniotic infections may occur with intact membranes. The etiology of intra-amniotic infection after PROM is almost always polymicrobial and consists of genital tract pathogens, such as group B streptococci, Chlamydia trachomatis, Neisseria gonorrhoeae, mycoplasmas, aerobic Gram-negative bacilli, such as the coliforms, and facultative and anaerobic endogenous organisms, such as peptococci, peptostreptococci, and Bacteroides species. These organisms gain access to the uterine cavity by the ascending route. Organisms such as Treponema pallidum, Listeria monocytogenes, Toxoplasma gondii, trypanosomes, and plasmodia are capable of gaining access to the amniotic cavity by transplacental hematogenous spread, and cause devastating fetal infections. Symptomatic intra-amniotic infection is usually a diagnosis of exclusion. Diagnostic criteria based on both clinical and laboratory findings lack sensitivity and are nonspecific. It is difficult to obtain uncontaminated intra-amniotic samples, especially when there is PROM. The problem is even greater with silent infections. In most cases, fetal infection is suspected after an unexplained and unexpected adverse outcome. Maternal morbidity is increased with intra-amniotic infection; although maternal mortality is extremely rare in developed countries, this is not the case in societies where pregnant women have limited or no access to medical care. Although infected women who are treated early and aggressively with wide-spectrum antibiotics do well, more than 10% of these women develop bacteremia and up to half of them will require cesarean delivery because of poor uterine contractions and arrest of labor. The overwhelming majority of term neonates exposed to intrauterine infection after PROM do well, but up to 30% of these neonates require treatment of neonatal pneumonia or bacteremia. Outcomes for preterm neonates or for neonates who experienced silent fetal infections are more severe. Morbidity and mortality rates in these cases are high, and survivors may have long-term devastating sequelae. The ability to identify ultrasound markers of fetal infection will help clinicians identify etiologic agents with greater accuracy and correlate these infections with specific antepartum and postpartum syndromes. The recognition of markers of intrauterine infection will also reduce unexpected adverse outcomes that result from undiagnosed fetal infections.

Ultrasound Markers of Fetal Infection Part 1

Diagnosis of fetal infection has depended on identification of pathogens by means of microbiological cultures, immunologic techniques, and special molecular biology techniques that can identify organisms known or suspected of being associated with adverse outcomes of pregnancy. Rubella, cytomegalovirus (CMV), herpes simplex virus (HSV), and human immunodeficiency virus (HIV), for example, are capable of gaining access to the amniotic cavity and producing fetal infection, even when amniotic membranes are intact. Intrauterine invasion by viruses can be associated with maternal symptoms of infection or can be completely silent. In many instances extensive fetal compromise with irreversible structural damage or fetal death will have occurred by the time infection is confirmed by culture or other histopathological methods. The evidence of fetal infection may be as subtle as nascent intrauterine growth restriction (IUGR), mildly inappropriate calcification of fetal organs, placenta, cord, and membranes, and failure to adequately develop fetal fat reserves. The evidence of infection may be as dramatic as obvious fetal malformation, severe central nervous system structural damage, or fetal death. Sonography is capable of detecting most of the grave alterations and some of the subtle effects that are typical of fetal infection.

Calcium deposition on the maternal surface of the human placenta: a scanning electron microscopic study

To explore the role of calcium in the materno-foetal relationship we decided to study the surface ultrastructure of the human placenta. Fresh pieces of tissues were obtained from central and peripheral parts of the maternal surface of human full-term placentas, processed and then examined with the Scanning Electron Microscope. Calcium depositions could only be seen at higher magnifications in forms of flecks, plaques, and concretions. They were frequently found in firm association with the tips of microvilli projecting from the apical parts of the syncytiotrophoblasts, which led to the clumping of those tips. Regional variations in the distribution of calcium deposits were apparent. Our findings indicate that placental calcification is a continual process occurring simultaneously in various parts of the placenta to varying degrees. Moreover, it seems possible that the process of placental calcification is of clinical and pathological significance bearing relationship to both maternal and foetal conditions.

Ultrasonographically observed early placental maturation and perinatal outcome

Perinatal outcome in 398 patients who had Grade II or Grade III placentas was analyzed in a cross-sectional study. Early placental maturation was identified in 51 patients. A trend toward lower mean birth weights was identified in the group with early placental maturation as compared to controls; however, statistical significance was achieved only in the Grade II population. In the Grade III population, early placental maturation identified a group of patients with a 16.7% incidence of growth retardation as compared to 4.1% in control patients (p less than 0.01). Early placental maturation was an insensitive predictor of poor perinatal outcome with respect to maternal hypertension, antepartum or intrapartum fetal distress, and perinatal asphyxia.

Placental morphometric and morphologic alterations in maternal undernutrition

Placentas, mothers, and neonates belonging to different socioeconomic groups were examined for morphometric and gross morphologic changes to assess the effect of maternal undernutrition. The mean maternal caloric intakes for socioeconomic Groups I, II, and IIII + IV are 2,919, 2420, and 1,589 calories per day, respectively, and differences were significant (P less than 0.001). The mean protein intakes were respectively, 76.1, 67.3, and 52.0 Gm. per day for socioeconomic Groups I, II, and III + IV, respectively (p less than 0.001). The birth weight, placental weight, volume, surface area, and number of cotyledon showed significantly decreasing trends (P less then 0.001) with the fall in socioeconomic group and maternal dietary intakes. Placentas of socioeconomic Group I had significantly higher incidence of well-defined cotyledons and central cord attachment. In lower socioeconomic groups and small-for-dates placentas there was significantly higher incidence of hemorrhages. There were no changes in incidences of placental infarcts, calcifications, and degeneration in various socioeconomic groups.

Placental aging monitored by gray scale echography

With gray scale ultrasonics echography, it is possible to identify changes in placental anatomy which formerly have been recognized only by examination of the placenta after delivery. By serial examinations these changes can be detected as they occur. The significance of the changes is discussed and an association between the premature appearance of aging of the placenta and a decline in placental function is noted.