Clinical associations with a placental diagnosis of delayed villous maturation: a retrospective study

Placenta histology related to flow and oxygenation in fetal congenital heart disease

BACKGROUND

Fetuses with congenital heart defects (CHD) show delayed neurodevelopment, fetal growth restriction (FGR) and placenta related complications. The neurodevelopmental delay may be, partly, attributed to placental factors.

AIM

As both placental development and fetal aortic flow/oxygenation influence neurodevelopment, placentas were compared within fetal CHD groups based on aortic oxygenation and flow, aiming to unravel the true effects in the developmental processes.

STUDY DESIGN

Placental tissues of pregnancies with fetal CHD and healthy controls were selected from biobanks of two Dutch academic hospitals (LUMC, UMCU). Additionally, biometry and Dopplers were assessed.

SUBJECTS

CHD cases with reduced oxygenation (RO) towards the fetal brain were compared to cases with reduced flow (RF) in the aortic arch and healthy controls. Genetic abnormalities, termination of pregnancy, fetal demise and/or multiple pregnancies were excluded.

OUTCOME MEASURES

Histological outcomes were related to fetal Dopplers and biometry. A placenta severity score was used to assess the severity of placental abnormalities per case.

RESULTS

In CHD, significantly more delayed maturation, maternal vascular malperfusion, fetal hypoxia and higher placenta severity scores (median 14 in RO, 14 in RF, 5 in controls, p < 0.001) were observed. Doppler abnormalities (PI UA > p90, PI MCA < p10, CPR < p10) and FGR were more often found in CHD. There were no differences in placental abnormalities, fetal growth and fetal Dopplers between cases with RO and RF.

CONCLUSION

Fetal hemodynamics in the ascending aorta could not be related to placenta characteristics. We hypothesize that placental development influences neurodevelopment in excess of hemodynamics in CHD cases.

Effect of Parity on Placental Histopathology Features in Singleton Live Births Following IVF

The aim of this study was to evaluate the effect of parity (primipara vs multipara) on the histopathology of the placenta in singleton live births following in vitro fertilization. We conducted a retrospective cohort study evaluating data of all IVF resulted live births from one university affiliated hospital during 2009-2017. All patients had the placenta sent for pathological evaluation. Exclusion criteria were history of miscarriage or elective termination of pregnancy, abnormal uterine cavity findings, previous uterine surgery, in vitro maturation cycles, gestational carrier cycles, oocyte recipient cycles, preimplantation genetic diagnosis cycles, and multiple pregnancies. The outcomes measured included anatomical, inflammation, vascular malperfusion, and villous maturation placental features. A multivariate analysis was conducted to adjust the results for factors potentially associated with placental pathology features. A total of 395 live births were included in the final analysis and were allocated to the study groups according to parity: primipara (n = 273) and multipara (n = 122). After adjustment for potential confounding factors, multiparity was found to be significantly associated with delayed villous maturation (OR 4.9; 95% CI 1.2-19.8) and primiparity was significantly associated with maternal vascular malperfusion (OR 0.6; 95% CI 0.3-0.8). We showed that parity has an impact on placental histopathological changes which in turn may affect perinatal outcome.

Stillbirth: prevention and supportive bereavement care

Around half of the two million stillbirths occurring worldwide each year are preventable. This review compiles the most up-to-date evidence to inform stillbirth prevention. Many general maternal health interventions also reduce the risk of stillbirth, for example, antenatal care attendance. This review focuses on specific aspects of care: glucose metabolism, targeted aspirin prophylaxis, clotting and immune disorders, sleep positions, fetal movement monitoring, and preconception and interconception health. In the past few years, covid-19 infection during pregnancy has emerged as a risk factor for stillbirth, particularly among women who were not vaccinated. Alongside prevention, efforts to address stillbirth must include provision of high quality, supportive, and compassionate bereavement care to improve parents' wellbeing. A growing body of evidence suggests beneficial effects for parents who received supportive care and were offered choices such as mode of birth and the option to see and hold their baby. Staff need support to be able to care for parents effectively, yet, studies consistently highlight the scarcity of specific bereavement care training for healthcare providers. Action is urgently needed and is possible. Action must be taken with the evidence available now, in healthcare settings with high or low resources, to reduce stillbirths and improve training and care.

Gestational Diabetes-Placental Expression of Human Equilibrative Nucleoside Transporter 1 (hENT1): Is Delayed Villous Maturation an Adaptive Pattern?

Gestational diabetes mellitus (GDM) is a metabolic disease that can affect placental villous maturation and villous vascularity. The main effects of GDM on placental growth are a delay of villous maturation (DVM) and decreased formation of vasculo-syncytial membranes (VSM). Human equilibrative nucleoside transporter-1 (hENT1) is an adenosine transporter expressed in the human umbilical vein endothelial cells (HUVEC) and human placental microvascular endothelium cells (hPMEC). Its role is crucial in maintaining physiological fetal adenosine levels during pregnancy, and its reduction has been described in GDM. Twenty-four placentas from pregnancies with a confirmed diagnosis of GDMd and twenty-four matched non-GDM placentas (controls) were retrospectively analyzed to investigate the immunohistochemical expression of hENT1 in HUVEC and hPMEC. The study included the quantitative evaluation of VSM/mm² in placental tissue and the immunohistochemical quantitative evaluation of Ki-67, PHH3, and p57 in villous trophoblast. hENT1 expression was higher in all the vascular districts of the control cases compared to the GDMd placentas (p < 0.0001). The VSM/mm² were lower in the GDMd cases, while the Ki-67, PHH3, and p57 were higher when compared to the control cases. To our knowledge, this is the first report of hENT1 expression in the human placentas of GDM patients. The absence/low expression of hENT1 in all the GDMd patients may indicate a potential role in microvascular adaptative mechanisms. The trophoblasts' proliferative/antiapoptotic pattern (high Ki-67, high PHH3, and high p57 count) may explain the statistically significant lower number of VSM/mm² found in the GDMd cases.

Placental delayed villous maturation is associated with fetal congenital heart disease

BACKGROUND

The placenta is crucial for the overall development and lifelong health of the fetus. Abnormal placental development and function occur in pregnancies with fetal congenital heart disease. However, studies that use standardized diagnostic criteria and incorporate control populations are lacking. This limits the generalizability of current research and the ability to determine the specific placental abnormalities associated with congenital heart disease.

OBJECTIVE

This study applied consensus statement guidelines (known as the Amsterdam criteria) for placental pathology interpretation to compare the frequency and pattern of abnormalities in pregnancies with fetal congenital heart disease to demographically matched control pregnancies and evaluate for differences in placental abnormalities by cardiac physiology.

STUDY DESIGN

A single-center retrospective cohort study was conducted from January 2013 to June 2019. Infants with a prenatal diagnosis of moderate-severe congenital heart disease who were born at ≥37 weeks of gestation were included. A control group born at ≥37 weeks of gestation but without fetal congenital heart disease or other major pregnancy complications was matched to the congenital heart disease group on maternal race and ethnicity and infant sex. Using the Amsterdam criteria, placental pathology findings were categorized as delayed villous maturation, maternal vascular malperfusion, fetal vascular malperfusion, and inflammatory lesions. The frequency of placental abnormalities was compared between groups, and logistic regression was performed to evaluate the association of clinical and sociodemographic factors with delayed villous maturation, maternal vascular malperfusion, and fetal vascular malperfusion.

RESULTS

There were 194 pregnancies with fetal congenital heart disease and 105 controls included, of whom 83% in the congenital heart disease group and 82% in the control group were of non-Hispanic White race and ethnicity. Compared with controls, pregnancies with fetal congenital heart disease had higher rates of delayed villous maturation (6% vs 19%; P<.001) and maternal vascular malperfusion (19% vs 34%; P=.007) but not fetal vascular malperfusion (6% vs 10%; P=.23). Infants with congenital heart disease with 2-ventricle anatomy displayed the highest odds of delayed villous maturation compared with controls (odds ratio, 5.5; 95% confidence interval, 2.2-15.7; P<.01). Maternal vascular malperfusion was 2.2 times higher (P=.02) for infants with 2-ventricle anatomy and 2.9 times higher (P=.02) for infants with single-ventricle physiology with pulmonic obstruction. Within the congenital heart disease group, delayed villous maturation was associated with higher maternal body mass index, polyhydramnios, larger infant birth head circumference, and infant respiratory support in the delivery room, whereas maternal vascular malperfusion was associated with oligohydramnios. In multivariable models adjusting for cardiac diagnosis, associations of delayed villous maturation persisted for infant birth head circumference (odds ratio, 1.2; 95% confidence interval, 1.0-1.5; P=.02) and infant respiratory support in the delivery room (odds ratio, 3.0; 95% confidence interval, 1.3-6.5; P=.007).

CONCLUSION

Pregnancies with fetal congenital heart disease displayed higher rates of delayed villous maturation and maternal vascular malperfusion than controls, suggesting that placental maldevelopment may relate to maternal factors. Future investigations are needed to determine the association of these abnormalities with postnatal infant outcomes.

Value of Placental Examination in the Diagnostic Evaluation of Stillbirth

ObjectiveThe aim was to assess the contribution of placental examination in the etiologic investigation of stillbirth. Materials and Methods: A retrospective review of stillbirths that occurred after 14 weeks gestation was conducted for a one-year period. Twin pregnancies and fetuses without placentas were excluded. According to the fetoplacental examination, stillbirths were classified into etiologic groups. Results: A total of 147 stillbirths were selected. They were associated with placental, materno-fetal, fetal and multiple causes in 89 cases (61%), 23 cases (16%), 14 cases (9%) and 13 cases (9%), respectively. Unexplained stillbirths were observed in 8 cases (5%). Placental abnormalities were identified in 132/147 cases (90%). They were consistent with vascular, inflammatory and developmental lesions in 82/132 cases (61%), 28/132 cases (21%) and 18/132 cases (13%), respectively. Conclusion: Placental lesions were the main causes of stillbirth and were predominantly of vascular type including chronic villous hypoxia-ischemia and funicular anomalies.

The role of the placenta in spontaneous preterm labor and delivery with intact membranes

OBJECTIVES

To determine whether placental vascular pathology and impaired placental exchange due to maturational defects are involved in the etiology of spontaneous preterm labor and delivery in cases without histologic acute chorioamnionitis.

METHODS

This was a retrospective, observational study. Cases included pregnancies that resulted in spontaneous preterm labor and delivery (<37 weeks), whereas uncomplicated pregnancies that delivered fetuses at term (≥37-42 weeks of gestation) were selected as controls. Placental histological diagnoses were classified into three groups: lesions of maternal vascular malperfusion, lesions of fetal vascular malperfusion, and placental microvasculopathy, and the frequency of each type of lesion in cases and controls was compared. Moreover, we specifically searched for villous maturational abnormalities in cases and controls. Doppler velocimetry of the umbilical and uterine arteries were performed in a subset of patients.

RESULTS

There were 184 cases and 2471 controls, of which 95 and 1178 had Doppler studies, respectively. The frequency of lesions of maternal vascular malperfusion was greater in the placentas of patients with preterm labor than in the control group [14.1% (26/184) vs. 8.8% (217/2471) (p=0.023)]. Disorders of villous maturation were more frequent in the group with preterm labor than in the control group: 41.1% (39/95) [delayed villous maturation in 31.6% (30/95) vs. 2.5% (13/519) in controls and accelerated villous maturation in 9.5% (9/95) vs. none in controls].

CONCLUSIONS

Maturational defects of placental villi were associated with approximately 41% of cases of unexplained spontaneous preterm labor and delivery without acute inflammatory lesions of the placenta and with delivery of appropriate-for-gestational-age fetuses.

Value of shear-wave elastography and cerebral-placental-uterine ratio in women diagnosed with preeclampsia and fetal growth restriction in prediction of adverse perinatal outcomes

PURPOSE

The aim of this study was to measure placental stiffness with shear-wave elastography technique and to evaluate the relationship with cerebral-placental-uterine ratio (CPUR) and adverse perinatal outcomes in patient groups diagnosed with preeclampsia (PE) and fetal growth restriction (FGR) in the second and third trimesters compared to the control group.

MATERIALS AND METHODS

This prospective cross-sectional study was conducted at our hospital between March 2019 and March 2020. The study groups were divided into three groups: PE, FGR, and low risk pregnancy (LRP) group. The study population had singleton pregnancies and the placental site was at the anterior wall. Both shear-wave elasticity (SWE) and shear-wave velocity (SWV) were measured in the placenta during pregnancy. CPUR was calculated for each group.

RESULTS

A total of 147 patients were included in this study. The mean SWE (kilopascals) values in the PE group were significantly higher than in the FGR and controls (difference of means = 3.67, 9.45; 95% CI (1.23-6.1, 7-11.8); p < .05), respectively. The mean SWV values were significantly higher in PE and FGR groups than controls (p < .05). CPUR showed correlation with central maternal surface of placenta (p: .02, r: -0.184), central fetal surface of placenta (p < .001, r: -0.288), peripheral maternal surface of placenta (p: .002, r: -0.252), and peripheral fetal surface of placenta SWE values (p: .03, r: -0.181). NICU admission was correlated with central fetal surface of placenta SWE values (p: .002, r: 0.258).

CONCLUSION

In conclusion, we demonstrated increased placental stiffness in both the PE and the FGR group. Also, this difference was found to be more prominent in preeclampsia. This technique seems useful for assessment of placental function and may strengthen the utility of Doppler parameters for predicting adverse perinatal outcomes in high-risk pregnancies.

Evaluation of the relationship between placental stiffness measured by shear wave elastography and perinatal outcomes in women with gestational diabetes mellitus

BACKGROUND

Recently, studies on placental elastography in high-risk pregnancies continue to increase. The shear wave technique can contribute to the management of gestational diabetes mellitus (GDM) and improve perinatal outcomes by measuring placental stiffness.Purpose: To evaluate the relationship between placental stiffness measured by shear wave elastography (SWE) and perinatal outcomes in women with GDM.Material and Methods: This prospective cross-sectional study was conducted at our hospital between March and October 2020. The participants were divided into three groups: GDM-A1 group (regulated by dietary modifications); GDM-A2 group (needed pharmacologic treatment); and low-risk pregnancy (LRP) group. Both SWE and shear wave velocity (SWV) were measured in the placenta during pregnancy.

RESULTS

In total, 111 women were included in the study. The mean SWE (kPa) values for the GDM-A1, GDM-A2, and LRP groups were 10.4 (range 3.1-23.3), 13 (range 4.3-29.6), and 8.3 (range 3.2-15.1), respectively. The mean HbA1c and fasting glucose values of diabetes groups showed strongly positive correlation with mean SWE and SWV values (P < 0.001, r=0.875; P < 0.001, r=0.856; P < 0.001, r=0.791; P < 0.001, r=0.740), respectively. The SWE values of central maternal and fetal surfaces of the placenta (P=0.01, r=0.242; P < 0.001, r=0.333) showed a moderately positive correlation with admission to the neonatal intensive care unit.

CONCLUSION

Placental stiffness has increased in the GDM-A2 group when compared to the GDM-A1 and LRP groups. We also observed a strong positive correlation between HbA1c, fasting glucose values, and increased elasticity values in diabetic patients with metabolic dysregulation that may have clinical value.

Placental pathology: Pathways leading to or associated with perinatal brain injury in experimental neurology, special issue: Placental mediated mechanisms of perinatal brain injury

Perinatal brain injury is a multifactorial process. In utero placental physiology plays a major role in neuroprotection and the normal development of the fetal central nervous system. Advances in placental pathology have clarified several specific mechanisms of injury and the histologic lesions most strongly associated with them. This review provides an updated summary of the relevant placental anatomy and physiology, the specific placental pathways leading to brain injury, the revised Amsterdam classification system for placental pathology, and the known associations of specific placental lesions with subtypes of adverse neurologic outcomes.

Histological Changes Observed in Placentas Exposed to Medication-Assisted Treatment

Introduction

To compare the effects of medication-assisted treatment on the placenta in pregnant women with opioid use disorder and uncomplicated pregnancies.

Methods

This is a case-controlled study of pregnant women utilizing medication-assisted treatment, buprenorphine or methadone, which were matched to healthy uncomplicated controls by gestational age. Placental evaluations and neonatal outcomes were evaluated. Data analysis performed standard statistics and relative risk analysis with a p < 0.05 considered significant.

Results

There were 143 women who met the inclusion criteria: 103 utilizing MAT, 41 buprenorphine and 62 methadone, and 40 uncomplicated matched healthy controls. The incidence of delayed villous maturation was 36% in the medication-assisted group compared with 10% in controls (RR 3.6: 95% CI 1.37-9.43; p < 0.01). The placental weight was greater (541 ± 117 g versus 491 ± 117 g; p = 0.02), and the fetoplacental weight ratio was lower (5.70 ± 1.1 versus 7.13 ± 1.4; p < 0.01) in the medication-exposed pregnancies compared with controls. The mean birth weight of the MAT newborns was significantly lower than that of the healthy controls (3018 ± 536 g versus 3380 ± 492 g; p < 0.01). When evaluating the subgroups of the MAT newborns, the birth weight of the methadone-exposed newborns (2886 ± 514 g) was significantly lower than that of the buprenorphine-exposed newborns (3218 ± 512 g; p < 0.01).

Conclusion

Medication-exposed pregnancies have a greater incidence of delayed villous maturation, a larger placental size, and a decreased fetoplacental weight ratio compared to the healthy controls. Larger long-term follow-up studies to evaluate outcomes with the presence of delayed villous maturation are needed.

Disorders of placental villous maturation are present in one-third of cases with spontaneous preterm labor

OBJECTIVES

Spontaneous preterm labor is an obstetrical syndrome accounting for approximately 65-70% of preterm births, the latter being the most frequent cause of neonatal death and the second most frequent cause of death in children less than five years of age worldwide. The purpose of this study was to determine and compare to uncomplicated pregnancies (1) the frequency of placental disorders of villous maturation in spontaneous preterm labor; (2) the frequency of other placental morphologic characteristics associated with the preterm labor syndrome; and (3) the distribution of these lesions according to gestational age at delivery and their severity.

METHODS

A case-control study of singleton pregnant women was conducted that included (1) uncomplicated pregnancies (controls, n=944) and (2) pregnancies with spontaneous preterm labor (cases, n=438). All placentas underwent histopathologic examination. Patients with chronic maternal diseases (e.g., chronic hypertension, diabetes mellitus, renal disease, thyroid disease, asthma, autoimmune disease, and coagulopathies), fetal malformations, chromosomal abnormalities, multifetal gestation, preeclampsia, eclampsia, preterm prelabor rupture of the fetal membranes, gestational hypertension, gestational diabetes mellitus, and HELLP (hemolysis, elevated liver enzymes and low platelet count) syndrome were excluded from the study.

RESULTS

Compared to the controls, the most prevalent placental lesions among the cases were the disorders of villous maturation (31.8% [106/333] including delayed villous maturation 18.6% [62/333] vs. 1.4% [6/442], q<0.0001, prevalence ratio 13.7; and accelerated villous maturation 13.2% [44/333] vs. 0% [0/442], q<0.001). Other lesions in decreasing order of prevalence included hypercapillarized villi (15.6% [68/435] vs. 3.5% [33/938], q<0.001, prevalence ratio 4.4); nucleated red blood cells (1.1% [5/437] vs. 0% [0/938], q<0.01); chronic inflammatory lesions (47.9% [210/438] vs. 29.9% [282/944], q<0.0001, prevalence ratio 1.6); fetal inflammatory response (30.1% [132/438] vs. 23.2% [219/944], q<0.05, prevalence ratio 1.3); maternal inflammatory response (45.5% [195/438] vs. 36.1% [341/944], q<0.01, prevalence ratio 1.2); and maternal vascular malperfusion (44.5% [195/438] vs. 35.7% [337/944], q<0.01, prevalence ratio 1.2). Accelerated villous maturation did not show gestational age-dependent association with any other placental lesion while delayed villous maturation showed a gestational age-dependent association with acute placental inflammation (q-value=0.005).

CONCLUSIONS

Disorders of villous maturation are present in nearly one-third of the cases of spontaneous preterm labor.

Placenta Pathology From Term Born Neonates With Normal or Adverse Outcome

BACKGROUND

The incidence of umbilical cord or placental parenchyma abnormalities associated with mortality or morbidity of term infants is lacking.

METHODS

Placentas of 55 antepartum stillbirths (APD), 21 intrapartum stillbirths (IPD), 12 neonatal deaths (ND), and 80 admissions to a level 3 neonatal intensive care unit (NS) were studied and compared with 439 placentas from neonates from normal term pregnancies and normal outcome after vaginal delivery (NPVD) and with 105 placentas after an elective caesarian sections (NPEC).

RESULTS

NPVD and NPEC placentas showed no or one abnormality in 70% and placentas from stillbirth showed two or more abnormalities in 80% of cases. APD placentas more frequently had a low weight and less formation of terminal villi. Hypercoiling was more often present in all study groups. Severe chronic villitis was almost exclusively present in APD placentas. Chorioamnionitis was significantly more frequent in APD, IPD and NS placentas and funisitis was more often observed in IPD and NS placentas.

CONCLUSION

Multiple placental abnormalities are significantly more frequent in placentas from term neonates with severe perinatal morbidity and mortality. These placental abnormalities are thought to be associated with disturbed oxygen transfer or with inflammation.

Placentas From Women of Advanced Maternal Age

CONTEXT.—

The percentage of pregnant women with advanced maternal age (AMA) has increased during the past several decades due to various socioeconomic factors and advances in assisted reproduction. These pregnancies are associated with adverse maternal and fetal outcomes. However, the underlying placental pathology has not been well described.

OBJECTIVE.—

To investigate the placental histopathology associated with AMA pregnancies.

DESIGN.—

Placental pathology from 168 AMA women 35 years or older at delivery was reviewed. The cases were subdivided into 2 age subgroups, ages 35 to 39 and 40 or older, as well as a "pure AMA" subgroup where the only indication for placental examination was AMA. A group of 60 consecutive non-AMA placentas was also identified and used as comparison. The spectrum of histologic features in each case was catalogued.

RESULTS.—

Of the overall AMA cases, meconium deposition was seen in 55% (93 of 168), chorangiosis in 40% (68 of 168), and acute chorioamnionitis in 36% (60 of 168). Fetal vascular malperfusion was also seen with high frequency (30%; 50 of 168). Two histologic alterations found to be significantly different between the 35 to 39 and greater than 40 age subgroups were fetal vascular malperfusion (11% [7 of 65] versus 42% [43 of 103]; P = .001) and delayed villous maturation (1.5% [1 of 65] versus 13% [13 of 103]; P = .02). The pure AMA subgroup showed no statistically significant differences compared with the overall AMA group. Chronic deciduitis was the only statistically significant difference between the overall AMA group and the non-AMA comparison group (14% [23 of 168] versus 30% [18 of 60]; P = .02).

CONCLUSIONS.—

Our findings, particularly the high frequency of fetal vascular malperfusion, suggest that AMA should be an independent indication for placental pathologic examination.

[Comparative morphofunctional analysis of the state of fetoplacental complex in diabetes mellitus (literature review)]

This article reviews the literature on placental morphofunctional changes in placenta of patients with type 1 and type 2 diabetes mellitus and gestational diabetes mellitus. The detailed analysis of features of pathogenesis of various abnormalities of the fetoplacental complex depending on the type of diabetes, its influence on the formation of the placental vascular bed. The analysis of mechanisms of development of placenta formation disorders, pathologies of placental vascular bed, the role of hyperglycemia and hyperinsulinemia in villous maturation, placental weight gain, perinatal outcomes. The discussed anomalies have a significant impact on the fetoplacental complex, acting as epigenetic factors, forming the environment for the fetus, which may later affect the health of the unborn child. They lead to adverse perinatal outcomes, including high infant morbidity and mortality. Literature search was performed in Russian (eLibrary, CyberLeninka.ru) and international (PubMed, Cochrane Library) databases in Russian and English languages. The free access to the full text of the articles was in priority. The selection of sources was prioritized for the period from 2016 to 2020. However, due to the lack of knowledge of the chosen topic, the selection of sources was dated from 2001.

Predictors of High Grade and Other Clinically Significant Placental Findings by Indication for Submission in Singleton Placentas From Term Births

Indications for placental submission are variable. Established guidelines are largely based on expert opinion, and there is a need for more evidence-based criteria. A 10-year database of term placentas was used to evaluate indications significantly associated with placental pathology. Lesions in 5 categories were separated into high- and low-grade subgroups. Two additional high-grade lesions were also evaluated. Indications associated with high-grade placental lesions were chronic monitoring abnormalities, severe preeclampsia, pregestational diabetes, maternal signs of infection, postdates pregnancy, artificial reproductive technology, drug abuse, umbilical cord entanglements, selected gross placental abnormalities, stillbirth, Apgar 5 minutes <6, small-for-gestational age infant, and macrosomia. Indications for which placental findings did not differ from the population as a whole were acute monitoring abnormalities, chronic hypertension, maternal obesity, vaginal bleeding, accessory lobe/multilobed placenta, meconium-stained fluid, single umbilical artery, and borderline large-for-gestational age infant. Other indications for submission were intermediate showing significant or borderline elevations in the prevalence of low- and high-grade lesions combined. We suggest on the basis of this study that guidelines for the submission of singleton term placentas could be modified to exclude cases with clinical indications that lack a significant association with placental lesions.

Effect of embryo stage at transfer on placental histopathology features in singleton live births resulting from fresh embryo transfers

OBJECTIVE

To evaluate the effect of embryo stage at transfer on placental histopathology and perinatal outcome in singleton live births resulting from fresh embryo transfers (ETs).

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

The study population included all live births after fresh ETs during the period from 2009 to 2017.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Primary outcomes included anatomic, inflammatory, vascular malperfusion, and villous maturation placental features. Secondary outcomes included fetal, maternal, and perinatal complications.

RESULT(S)

A total of 677 live births were included in the final analysis and were allocated to the cleavage-stage (n = 252) and blastocyst (n = 425) ET groups. After the adjustment for confounding factors, the blastocyst group was found to be associated with a higher incidence of circummarginate membranes insertion (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.2-3.4), delayed villous maturation (OR 8.5, 95% CI 1.2-69.3), chorangiosis (OR 2.0, 95% CI 1.2-3.8), parenchymal calcifications (OR 10.6, 95% CI 1.4-80.2), and intrapartum nonreassuring fetal heart rate tracing (OR 2.4, 95% CI 1.3-4.5). Compared with cleavage-stage ETs, live births resulting from the blastocysts were associated with a lower incidence of velamentous cord insertion (OR 0.5, 95% CI 0.3-0.9), retroplacental hematoma (OR 0.3, 95% CI 0.1-0.8), subchorionic thrombi (OR 0.3, 95% CI 0.1-0.8), and avascular villi (OR 0.2, 95% CI 0.03-0.7).

CONCLUSION(S)

Live births resulting from fresh cleavage-stage and blastocyst ETs have different placental histopathology features, with a higher rate of intrapartum nonreassuring fetal heart rate tracing in the blastocyst group.

Discordant Zika Virus Findings in Twin Pregnancies Complicated by Antenatal Zika Virus Exposure: A Prospective Cohort

BACKGROUND

There are limited data on the natural history of antenatal Zika virus (ZIKV) exposure in twin pregnancies, especially regarding intertwin concordance of prenatal, placental, and infant outcomes.

METHODS

This prospective cohort study included twin pregnancies referred to a single institution from September 2015 to June 2016 with maternal ZIKV. Polymerase chain reaction (PCR) testing of maternal, placental, and neonatal samples was performed. Prenatal ultrasounds were completed for each twin, and histomorphologic analysis was performed for each placenta. Abnormal neonatal outcome was defined as abnormal exam and/or abnormal imaging. Two- to three-year follow-up of infants included physical exams, neuroimaging, and Bayley-III developmental assessment.

RESULTS

Among 244 pregnancies, 4 twin gestations without coinfection were identified. Zika virus infection occurred at 16-33 weeks gestation. Zika virus PCR testing revealed discordance between dichorionic twins, between placentas in a dichorionic pair, between portions of a monochorionic placenta, and between a neonate and its associated placenta. Of the 8 infants, 3 (38%) had an abnormal neonatal outcome. Of 6 infants with long-term follow-up, 3 (50%) have demonstrated ZIKV-related abnormalities.

CONCLUSIONS

Neonatal PCR testing, placental findings, and infant outcomes can be discordant between co-twins with antenatal ZIKV exposure. These findings demonstrate that each twin should be evaluated independently for vertical transmission.

Gastroschisis Is Associated With Placental Delayed Villous Maturation

Gastroschisis is a congenital abnormality characterized by visceral herniation through an abdominal wall defect. While the cause of gastroschisis is unknown, it has been linked to risk factors including young maternal age, smoking, and alcohol use during pregnancy. To date, the only established placental correlate is amniocyte vacuolization. Based on our clinical experience, we hypothesized that delayed villous maturation (DVM) is also associated with gastroschisis. We conducted a retrospective slide review of 23 placentas of neonates with gastroschisis. Additionally, we selected 2 control groups of placentas: 1 with a previous diagnosis of DVM and 1 with normal villous morphology. All placentas were randomized and reviewed by 2 perinatal pathologists, who were blinded to the group; DVM and amniocyte vacuolization were assessed. Gastroschisis was associated with increased placental DVM in 65.2% of cases (vs 13.6% of controls; P = .0007) and increased amniocyte vacuolization in 52.2% of cases (vs 9.1% of controls; P = .003) compared to the control group. Based on the normal and DVM groups, kappa agreement between current slide review and initial pathology diagnosis was 0.419, indicating moderate agreement. Our study shows that gastroschisis is associated with placental DVM. This association may be due to (1) a common upstream factor contributing to both gastroschisis and DVM or (2) DVM may be a consequence of the altered placental and amniotic environment in the context of gastroschisis.

Disorders of placental villous maturation in fetal death

Objective The aims of this study were to ascertain the frequency of disorders of villous maturation in fetal death and to also delineate other placental histopathologic lesions in fetal death. Methods This was a retrospective observational cohort study of fetal deaths occurring among women between January 2004 and January 2016 at Hutzel Women's Hospital, Detroit, MI, USA. Cases comprised fetuses with death beyond 20 weeks' gestation. Fetal deaths with congenital anomalies and multiple gestations were excluded. Controls included pregnant women without medical/obstetrical complications and delivered singleton, term (37-42 weeks) neonate with 5-min Apgar score ≥7 and birthweight between the 10th and 90th percentiles. Results Ninety-two percent (132/143) of placentas with fetal death showed placental histologic lesions. Fetal deaths were associated with (1) higher frequency of disorders of villous maturation [44.0% (64/143) vs. 1.0% (4/405), P < 0.0001, prevalence ratio, 44.6; delayed villous maturation, 22% (31/143); accelerated villous maturation, 20% (28/143); and maturation arrest, 4% (5/143)]; (2) higher frequency of maternal vascular malperfusion lesions [75.5% (108/143) vs. 35.7% (337/944), P < 0.0001, prevalence ratio, 2.1] and fetal vascular malperfusion lesions [88.1% (126/143) vs. 19.7% (186/944), P < 0.0001, prevalence ratio, 4.5]; (3) higher frequency of placental histologic patterns suggestive of hypoxia [59.0% (85/143) vs. 9.3% (82/942), P < 0.0001, prevalence ratio, 6.8]; and (4) higher frequency of chronic inflammatory lesions [53.1% (76/143) vs. 29.9% (282/944), P < 0.001, prevalence ratio 1.8]. Conclusion This study demonstrates that placentas of women with fetal death were 44 times more likely to present disorders of villous maturation compared to placentas of those with normal pregnancy. This suggests that the burden of placental disorders of villous maturation lesions is substantial.

Placental changes in diabetic pregnancies and the contribution of hypertension

Objective: To evaluate placental abnormalities in pregnancies affected by diabetes compared to unaffected pregnancies from a single academic center.Methods: This is a retrospective cohort study of women with singleton gestations delivered at the University of Arkansas for Medical Sciences from 2007 to 2016. Pathologic examination of placentas from pregestational and gestational diabetic pregnancies were compared to placentas from patients without diabetes using 12 histologic elements. Maternal and neonatal outcomes were extracted from the medical record and compared between groups. Findings were adjusted for hypertensive disorders of pregnancy. Placental lesions were also correlated with diabetic control.Results: Pathology reports of 590 placentas along with corresponding medical records were reviewed. The diabetic group (N = 484) consisted of 188 patients with pregestational diabetes and 296 patients with gestational diabetes. The nondiabetic group consisted of 106 patients. The diabetic group was older, had a higher average BMI, and more hypertensive disorders (p < .0001). Out of the 12 histologic elements investigated, accelerated villous maturation (aOR = 8.45, 95%CI (1.13-62.95)) and increased placental weight (aOR = 3.131, 95% CI (1.558-6.293)) were noted to be significantly increased in placentas from diabetic pregnancies after controlling for hypertension. Intervillous thrombi were not significantly increased in pregnancies affected by diabetes. Neonates of the diabetic group were more likely to be large for gestational age (p < .0001) and had a higher rate of preterm delivery (p < .0001).Conclusions: Accelerated villous maturation was found to be more frequent in pregnancies complicated by pregestational diabetes, even after controlling for hypertension. In pregnancies complicated by gestational diabetes, the placental findings were not significant after controlling for hypertension. In contrast with prior studies, there was no increase in thrombotic lesions of the placenta in patients with diabetes.

High-mobility group box 1 at the time of parturition in women with gestational diabetes mellitus

PROBLEM

High-mobility group box 1 (HMGB1), a danger-associated molecular pattern marker, may indicate sterile inflammation through innate immune pathways. HMGB1 is implicated in hyperglycemia and excess glucose in trophoblast. Metabolic dysfunction and dyslipidemia are associated with gestational diabetes mellitus (GDM), but few studies examined associations between HMGB1 and GDM. We determined HMGB1 levels, and the ratio of HMGB1 to innate immune markers, in women with GDM at parturition.

METHOD OF STUDY

This case-control study of 50 GDM pregnancies and 100 healthy controls utilized data and plasma samples from PeriBank. HMGB1, pentraxin-3, and interleukin (IL)-6 were measured by ELISA. Logistic regression calculated odds ratios (OR) and 95% confidence intervals (CI) adjusting for age, pre-pregnancy body mass index, and type of labor.

RESULTS

There were no significant associations between HMGB1 and GDM. The ratio of HMGB1 to pentraxin-3 and IL-6 did not alter the odds of GDM. There was a significant statistical interaction between HMGB1 and maternal age (P = .02). When associations were examined by age groups, HMGB1 was associated with reduced odds of HMGB1 among women ≤25 (AOR = 0.007 CI 95% <0.001-0.3). Odds ratios increased as age increased (AOR range 1.2-3.8) but results were not statistically significant.

CONCLUSION

High-mobility group box 1 was not associated with GDM. However, we found evidence that maternal age was a potential effect modifier of the relationship between HMGB1 and GDM. As there is growing evidence that HMGB1 may play important roles in reproduction, future studies should explore maternal factors that may alter HMGB1 levels.

Association of Maternal Prepregnancy Body Mass Index With Placental Histopathological Characteristics in Uncomplicated Term Pregnancies

INTRODUCTION

Prepregnancy obesity is a growing global health problem and has several risks for mother and child. The aim of this study was to systematically examine the effect of increased maternal body mass index (BMI) on placental pathology in otherwise uneventful term pregnancies.

METHODS

In this analysis, we studied data of the Netherlands Amniotic Fluid study, a prospective study of women delivering in Utrecht, the Netherlands, between 2006 and 2007. We included women with uncomplicated pregnancies, vaginal delivery, and data on prepregnancy weight and height (n = 382). Placental histopathology was compared between women of normal BMI (≤24.9 kg/m²), overweight (25-29.9 kg/m²), and obese (≥30 kg/m²).

RESULTS

Increasing prepregnancy BMI was associated with heavier placentas and higher mean infant's birth weight. In addition, obesity was positively associated with high-grade chronic villitis (odds ratio [OR]: 18.1, 95% confidence interval [CI]: 1.6-205.2), accelerated villous maturation (OR: 1.1, 95% CI: 1.0-1.2), and lower incidence of placental weight below the 10th percentile for gestational age (OR: 0.5, 95% CI: 0.3-1.0). There was a substantial effect of parity on maternal, placental, and neonatal weights.

CONCLUSIONS

Even in uncomplicated pregnancies, maternal obesity is associated with characteristic changes in placental pathology. Further research is needed to evaluate these changes in view of later-life health of infants born to obese mothers.

Re-view and view on maturation disorders in the placenta

Until delivery, the placenta plays an important mediator role between mother and fetus. This unit is affected by peristatic conditions, such as acute or chronic maternal diseases, malnutrition, drugs, and others. But also genetic factors and fetal malformations due to embryonic developmental disorders may contribute to macroscopically visible changes and functional disorders of the placenta. In a constantly ongoing progress of maturation, the placenta records and saves changes due to fetal distress partly as maturation disorders. Understanding of maturation disorders might, therefore, be an important contribution to a better understanding of influences on villous differentiation and might improve follow up and fetal outcome to reduce recurrence risk. However, an internationally unified classification system of maturation disorders does not exist. In this review, terminology, trials, and classifications of villous maturation disorders are summed up and compared, to pinpoint the need of agreement on an international unified and reproducible classification of maturation disorders.

Gene markers of normal villous maturation and their expression in placentas with maturational pathology

INTRODUCTION

The placenta demonstrates a recognized sequence of histomorphologic maturation throughout pregnancy, and in some cases, shows abnormally advanced (AVM) or delayed (DVM) villous maturation. While AVM and DVM have important clinical implications, it is unknown whether they truly represent a state of accelerated/delayed normal maturation or a state of pathological maldevelopment. The purpose of our study is, therefore, to address this challenge via a genome-wide search for expression markers of normal villous maturation (NM) and the assessment of these genes in cases of maturational pathology.

METHODS

A total of 142 placentas, previously evaluated by gene expression microarray, were reviewed histologically and classified as NM, AVM, or DVM. Expression data from healthy NM placentas underwent Pearson correlations with gestational age (GA) and network/pathway analysis to identify candidate gene markers. Candidates were then validated in an independent microarray dataset and used to calculate "molecular GAs" of placentas with maturational pathology.

RESULTS

Analysis of NM placentas yielded 17 candidate markers of normal villous maturation, of which 11 were independently validated. Genes with expression increasing across gestation were associated with transcription and metabolism, while those demonstrating decreasing expression were involved in cell cycle and division. Molecular GA was 5.3 weeks older than true GA among AVM placentas (p < 0.001), and 1.1 weeks younger among DVM placentas (p = 0.149).

DISCUSSION

We have found evidence of advanced molecular GA in AVM placentas, while molecular alterations in DVM placentas were merely suggestive of delayed maturation. In the future, these findings will need to be validated with additional techniques such as in situ hybridization or immunohistochemistry.

Delayed villous maturation in term placentas exposed to opioid maintenance therapy: a retrospective cohort study

BACKGROUND

Opioid use disorder among pregnant women is associated with adverse perinatal outcomes and is increasing in the United States. The standard of care for pregnant women with opioid use disorder is opioid maintenance therapy including either methadone or buprenorphine, which can be initiated at any time during pregnancy. These medications are known to cross the placenta but their placental and fetal effects have not been well characterized. Delayed villous maturation, a placental finding associated with stillbirth, was observed in placentas exposed to opioid maintenance therapy. Given the association of delayed villous maturation with stillbirth, and the possible relationship between opioid maintenance therapy and delayed villous maturation, this study was undertaken to explore the association between opioid maintenance therapy and this placental finding. Delayed villous maturation was not previously reported in placentas exposed to opioids or opioid maintenance therapy.

OBJECTIVE

This study sought to compare risk of delayed villous maturation in term placentas exposed and unexposed to opioid maintenance therapy with buprenorphine or methadone.

STUDY DESIGN

This was a retrospective cohort study conducted between 2010 through 2012 at Magee-Womens Hospital comparing delayed villous maturation in placentas of women with opioid use disorder exposed to either buprenorphine (n = 86) or methadone (n = 268) versus women without opioid use disorder (n = 978). Potential covariates were assessed in univariate analyses with none significantly associated with delayed villous maturation. The final model used conditional logistic regression adjusting for smoking status alone.

RESULTS

Among women without opioid use disorder (and therefore not exposed to opioid maintenance therapy), delayed villous maturation was identified in 5.7% of placentas while the prevalence among women treated with buprenorphine or methadone was 8.1% and 10.8%. Overall, the crude odds of being diagnosed with delayed villous maturation were significantly greater in those exposed to opioid maintenance therapy compared to those not exposed (odds ratio, 1.86; 95% confidence interval, 1.20-2.89). When considered separately, women treated with methadone had significantly greater odds of having a placenta with delayed villous maturation than women without exposure to opioid maintenance therapy (odds ratio, 2.00; 95% confidence interval, 1.52-3.20). Women treated with buprenorphine did not have significantly greater odds of this placental diagnosis when compared to the women unexposed to opioid maintenance therapy (odds ratio, 1.46; 95% confidence interval, 0.64-3.31). Results were similar after accounting for smoking.

CONCLUSION

Delayed villous maturation was more common in the placentas of women exposed to opioid maintenance therapy. Further studies are required to characterize rates and extent of delayed villous maturation in the general population as well as to differentiate between possible effects of opioid exposure (eg, heroin, illicit use of prescription opioids) vs those of opioid maintenance therapy (buprenorphine and methadone).

Decidual arteriolopathy with or without associated hypertension modifies the underlying histomorphology in placentas from diabetic mothers

AIM

The aim of this study was to retrospectively document the impact of hypertensive conditions in pregnancy and decidual arteriolopathy on the patterns of placental injury in maternal diabetes mellitus (MDM).

METHODS

Among all 5248 > 20 weeks' placentas, the frequencies of 19 selected clinical and 24 placental phenotypes were compared between 287 MDM placentas and 4961 remaining placentas (control group [CG]) before and after further exclusion of 85 and 611 patients with hypertensive conditions (gestational hypertension, pre-eclampsia, chronic hypertension).

RESULTS

Cesarean section rate, heavy placentas, decidual arteriolopathy, microscopic chorionic pseudocysts, and chorangiosis were more common in MDM than in the CG both before and after exclusion of hypertensive conditions. The frequencies of preuterine patterns of chronic hypoxic placental injury and plasma cell deciduitis became statistically significant only after exclusion of hypertensive conditions.

CONCLUSION

Hypertensive conditions of pregnancy may obscure the underlying preuterine placental hypoxic pattern in MDM placentas. Even in normotensive patients, decidual arteriolopathy, and shallow placental implantation significantly impact placental histomorphology in MDM.

Alcohol, Methamphetamine, and Marijuana Exposure Have Distinct Effects on the Human Placenta

BACKGROUND

Animal studies have demonstrated adverse effects of prenatal alcohol exposure on placental development, but few studies have examined these effects in humans. Little is known about effects of prenatal exposure to methamphetamine, marijuana, and cigarette smoking on placental development.

METHODS

Placentas were collected from 103 Cape Coloured (mixed ancestry) pregnant women recruited at their first antenatal clinic visit in Cape Town, South Africa. Sixty-six heavy drinkers and 37 nondrinkers were interviewed about their alcohol, cigarette smoking, and drug use at 3 antenatal visits. A senior pathologist, blinded to exposure status, performed comprehensive pathology examinations on each placenta using a standardized protocol. In multivariable regression models, effects of prenatal exposure were examined on placental size, structure, and presence of infections and meconium.

RESULTS

Drinkers reported a binge pattern of heavy drinking, averaging 8.0 drinks/occasion across pregnancy on 1.4 d/wk. 79.6% smoked cigarettes; 22.3% used marijuana; and 17.5% used methamphetamine. Alcohol exposure was related to decreased placental weight and a smaller placenta-to-birthweight ratio. By contrast, methamphetamine was associated with larger placental weight and a larger placenta-to-birthweight ratio. Marijuana was also associated with larger placental weight. Alcohol exposure was associated with increased risk of placental hemorrhage. Prenatal alcohol, drug, and cigarette use were not associated with chorioamnionitis, villitis, deciduitis, or maternal vascular underperfusion. Alcohol and cigarette smoking were associated with a decreased risk of intrauterine passing of meconium, a sign of acute fetal stress and/or hypoxia; methamphetamine, with an increased risk.

CONCLUSIONS

This is the first human study to show that alcohol, methamphetamine, and marijuana were associated with distinct patterns of pathology, suggesting different mechanisms mediating their effects on placental development. Given the growing body of evidence linking placental abnormalities to neurodevelopmental deficits, these findings may be important in the long-term teratogenic effects of prenatal alcohol and drug exposure.

Image-Based Modeling of Blood Flow and Oxygen Transfer in Feto-Placental Capillaries

During pregnancy, oxygen diffuses from maternal to fetal blood through villous trees in the placenta. In this paper, we simulate blood flow and oxygen transfer in feto-placental capillaries by converting three-dimensional representations of villous and capillary surfaces, reconstructed from confocal laser scanning microscopy, to finite-element meshes, and calculating values of vascular flow resistance and total oxygen transfer. The relationship between the total oxygen transfer rate and the pressure drop through the capillary is shown to be captured across a wide range of pressure drops by physical scaling laws and an upper bound on the oxygen transfer rate. A regression equation is introduced that can be used to estimate the oxygen transfer in a capillary using the vascular resistance. Two techniques for quantifying the effects of statistical variability, experimental uncertainty and pathological placental structure on the calculated properties are then introduced. First, scaling arguments are used to quantify the sensitivity of the model to uncertainties in the geometry and the parameters. Second, the effects of localized dilations in fetal capillaries are investigated using an idealized axisymmetric model, to quantify the possible effect of pathological placental structure on oxygen transfer. The model predicts how, for a fixed pressure drop through a capillary, oxygen transfer is maximized by an optimal width of the dilation. The results could explain the prevalence of fetal hypoxia in cases of delayed villous maturation, a pathology characterized by a lack of the vasculo-syncytial membranes often seen in conjunction with localized capillary dilations.

Sampling and Definitions of Placental Lesions: Amsterdam Placental Workshop Group Consensus Statement

CONTEXT

-The value of placental examination in investigations of adverse pregnancy outcomes may be compromised by sampling and definition differences between laboratories.

OBJECTIVE

-To establish an agreed-upon protocol for sampling the placenta, and for diagnostic criteria for placental lesions. Recommendations would cover reporting placentas in tertiary centers as well as in community hospitals and district general hospitals, and are also relevant to the scientific research community.

DATA SOURCES

-Areas of controversy or uncertainty were explored prior to a 1-day meeting where placental and perinatal pathologists, and maternal-fetal medicine specialists discussed available evidence and subsequently reached consensus where possible.

CONCLUSIONS

-The group agreed on sets of uniform sampling criteria, placental gross descriptors, pathologic terminologies, and diagnostic criteria. The terminology and microscopic descriptions for maternal vascular malperfusion, fetal vascular malperfusion, delayed villous maturation, patterns of ascending intrauterine infection, and villitis of unknown etiology were agreed upon. Topics requiring further discussion were highlighted. Ongoing developments in our understanding of the pathology of the placenta, scientific bases of the maternofetoplacental triad, and evolution of the clinical significance of defined lesions may necessitate further refinements of these consensus guidelines. The proposed structure will assist in international comparability of clinicopathologic and scientific studies and assist in refining the significance of lesions associated with adverse pregnancy and later health outcomes.

May maternal lifestyle have an impact on neonatal glucose levels?

Neonatal glucose levels correlate negatively with umbilical cord levels of C-peptide, a polypeptide secreted with insulin. In other words, neonatal hypoglycemia results from excessive insulin secretion from fetal/neonatal beta cells. Given that insulin causes fat to be stored rather than to be used for energy, one would expect that chronic hyperinsulinemia would result in large-for-gestational-age neonates. The finding that many small-for-gestational-age neonates have hypoglycemia suggests that the stimulus for insulin production occurs close to delivery. We postulated that a potent stimulation of maternal insulin production close to delivery would also provide a potent stimulus for fetal and neonatal insulin production, causing neonatal hypoglycemia. This study has evaluated 155 mothers with markers of excessive insulin production (such as acanthosis or grade III obesity), or with situations characterized by increased insulin requirements (such as an invasive bacterial infection or use of systemic corticosteroid within a week before delivery; or sedentariness or high-carbohydrate intake within 24h before delivery) and their 158 neonates who were screened for glycemic levels at 1, 2 and 4h after birth. The minimum glucose level was correlated to the maternal parameters, and to classical predictors of neonatal hypoglycemia, such as low-birth weight and preterm delivery. The only independent predictors were sedentariness and high-carbohydrate intake within 24h before delivery. The risk of neonatal hypoglycemia increased five-fold with sedentariness, 11-fold with high-carbohydrate intake, and 329-fold with both risk factors. The risk of neonatal hypoglycemia seems to be highly influenced by maternal lifestyle within 24h before delivery. Controlled randomized trials may help determine whether a controlled carbohydrate diet combined with regular physical activity close to delivery can prevent neonatal hypoglycemia and all its severe complications to the newborn.

"Delayed Villous Maturation" in Placental Reporting: Concordance among Consultant Pediatric Pathologists at a Single Specialist Center

Delayed villous maturation (DVM) has been associated with an increased risk of adverse pregnancy outcome, including stillbirth, in the late third trimester, but there are limited published data. Moreover, it is recognized that the assessment of villous maturation is subjective and hampered by both intraobserver and interobserver variability. This audit aims to assess concordance in the reporting of DVM among pediatric pathologists at a single specialist center to improve reproducibility of this potentially important diagnosis. This is a retrospective review of singleton placentas from pregnancies at 35 weeks gestation or greater submitted for histopathologic examination between June 2013 and December 2013. Placental slides were reviewed independently by 4 pediatric pathologists, blinded to the original report, apart from gestational age; villous maturation was assessed as appropriate, accelerated, or delayed for the stated gestational age. A total of 464 placental histopathology reports were reviewed, of which 164 were greater than 35 weeks gestation; of those, 42 (26%) were originally reported as DVM. Following the audit slide review, 38 cases (23%) were assessed to show DVM by at least 1 pathologist. Consensus, with at least 3 pathologists agreeing to a diagnosis of DVM, was achieved in only 14 cases (9% of all cases reviewed; 37% of all cases called DVM). However, the proportion of overall agreement between 2 of the pathologists was 0.92. Concordance for DVM is poor among pathologists and subject to much interobserver variability. Consistency may be improved by consensus histologic review of all the placentas in which the diagnosis of DVM is being considered and stringent application of the published diagnostic criteria.

Type 1, type 2 and gestational diabetes mellitus differentially impact placental pathologic characteristics of uteroplacental malperfusion

INTRODUCTION

During a pregnancy complicated by diabetes, the placenta undergoes a number of functional and structural pathologic changes. However, differences across studies may reflect pathophysiologic differences of diabetes types under investigation.

METHODS

We examined placental pathology from women ages 18-40 years with self-identified race/ethnicity; singleton, live births; and type 1 (T1DM; n = 36), type 2 (T2DM; n = 37), or gestational diabetes mellitus (GDM; n = 126). Clinical data were abstracted from medical records. Placental diagnoses were independently re-reviewed by a perinatal pathologist. Multivariable analyses adjusting for race, gestational weight gain, gestational age, and systolic blood pressure were conducted.

RESULTS

Women with T1DM compared with either T2DM or GDM had higher gestational weight gain (mean ± SD, T1DM vs. T2DM: 28.5 ± 12.4 vs. 20.5 ± 13.4 kg, p = 0.03; or GDM: 21.3 ± 12.7 kg, p = 0.009) and insulin use (T2DM: 100.0% vs. 85.3%, p = 0.02; or GDM: 4.0%, p < 0.001). Women with T1DM compared with either T2DM or GDM also had a similarly lower prevalence of placental infarcts in univariate analyses; however, these findings did not remain significant after multivariable adjustment. Also, placentas from women with T2DM compared to GDM had higher rates of decidual vasculopathy when excluding women with preeclampsia (10.3 vs. 1.6%, p = 0.049) and diffuse chorangiosis (62.2 vs. 32.5%, p < 0.001) but a lower rate of villous immaturity (10.8 vs. 90.5%, p = 0.007) after full adjustment.

DISCUSSION

Placental vasculopathic abnormalities differ by maternal diabetes type, potentially reflecting underlying pathophysiologic mechanisms. Further research on placental pathology and metabolic derangements is warranted.

A systematic review of placental pathology in maternal diabetes mellitus

INTRODUCTION

During a pregnancy complicated by diabetes, the human placenta undergoes a number of functional and structural pathologic changes, such as increased placental weight and increased incidence of placental lesions including villous maturational defects and fibrinoid necrosis. The pathologic findings reported have differed among studies, potentially reflecting differences in type of diabetes, study methodology, or glycemic control of study participants. Alternatively, these discrepancies may represent different biologic adaptations to distinct metabolic diseases.

METHODS

We conducted a comprehensive review of English language citations in Pubmed and Embase using the keywords "diabetes", "placenta", AND "pathology". Abstracts were reviewed for relevance then full-text articles were reviewed in order to extract a comprehensive summary of current pathological findings associated with pregestational and gestational diabetes mellitus, as well as an understanding of the impact of glycemic control on placental pathology.

RESULTS

Placental abnormalities most consistently associated with maternal diabetes are an increased incidence of villous immaturity, increased measures of angiogenesis, and increased placental weight.

CONCLUSIONS

The literature suggests that, despite similarities in placental abnormalities, differences in placental pathology may reflect differences in pathophysiology among different types of diabetes. Consequently, standardization of terminology used to define placental lesions is warranted. Moreover, further research is needed to investigate the impact of pathophysiology, glycemic control and clinical factors, such as infant sex, weight and race, on placental structure and function.

Pathologic evaluation of normal and perfused term placental tissue

This study reports for the 1st time the incidence and interobserver variation of morphologic findings in a series of 34 term placentas from pregnancies with normal outcome used for perfusion studies. Histologic evaluation of placental tissue is challenging, especially when it comes to defining "normal tissue" versus "pathologic lesions." A scoring system for registration of abnormal morphologic findings was developed. Light microscopic examination was performed independently by 2 pathologists, and interobserver variation was analyzed. Findings in normal and perfused tissue were compared and selected findings were tested against success parameters from the perfusions. Finally, the criteria for frequent lesions with fair to poor interobserver variation in the nonperfused tissue were revised and reanalyzed. In the perfused tissue, the perfusion artefact "trophoblastic vacuolization," which is believed to represent dilated transtrophoblastic channels, was reproducible and significantly correlated to the perfusion marker "fetal leakage." In longer perfusions, microscopy of the perfused cotyledon revealed bacteria in the fetal vessels. This finding led to an adjustment in the perfusion protocol with addition of antibiotics to the medium. In the "normal" tissue, certain lesions were very frequent and showed only fair or poor interobserver agreement. Revised minimum criteria for these lesions were defined and found reproducible. This study has emphasized the value of pathologic examination as a supplement in placental perfusion models. Examination of the perfused cotyledon for trophoblastic vacuolization is recommended as an additional quality marker in perfusion models. The study also underlines the need for exact definitions of abnormality in frequent placental lesions.

Novel placental ultrasound assessment: potential role in pre-gestational diabetic pregnancy

OBJECTIVES

Management of women with pre-gestational diabetes continues to be challenging for clinicians. This study aims to determine if 3D power Doppler (3DPD) analysis of placental volume and flow, and calculation of placental calcification using a novel software method, differ between pregnancies with type 1 or type 2 diabetes and normal controls, and if there is a relationship between these ultrasound placental parameters and clinical measures in diabetics.

METHODS

This was a prospective cohort study of 50 women with diabetes and 250 controls (12-40 weeks gestation). 3DPD ultrasound was used to evaluate placental volume, vascularisation index (VI), flow index (FI) and vascularisation-flow index (VFI). Placental calcification was calculated by computer analysis. Results in diabetics were compared with control values, and correlated with early pregnancy HbA1c, Doppler results and placental histology.

RESULTS

Placental calcification and volume increased with advancing gestation in pre-gestational diabetic placentae. Volume was also found to be significantly higher than in normal placentae. VI and VFI were significantly lower in diabetic pregnancies between 35 and 40 weeks gestation. A strong relationship was seen between a larger placental volume and both increasing umbilical artery pulsatility index and decreasing middle cerebral artery pulsatility index. FI was significantly lower in cases which had a booking HbA1c level ≥6.5%. Ultrasound assessed placental calcification was reduced with a histology finding of delayed villous maturation. No other correlation with placental histology was found.

CONCLUSIONS

This study shows a potential role for 3D placental evaluation, and computer analysis of calcification, in monitoring pre-gestational diabetic pregnancies.

Placental pathology in full-term infants with hypoxic-ischemic neonatal encephalopathy and association with magnetic resonance imaging pattern of brain injury

OBJECTIVE

To investigate the relationship between placental pathology and pattern of brain injury in full-term infants with neonatal encephalopathy after a presumed hypoxic-ischemic insult.

STUDY DESIGN

The study group comprised full-term infants with neonatal encephalopathy subsequent to presumed hypoxia-ischemia with available placenta for analysis who underwent cerebral magnetic resonance imaging (MRI) within the first 15 days after birth. Macroscopic and microscopic characteristics of the placenta were assessed. The infants were classified according to the predominant pattern of brain injury detected on MRI: no injury, predominant white matter/watershed injury, predominant basal ganglia and thalami (BGT) injury, or white matter/watershed injury with BGT involvement. Maternal and perinatal clinical factors were recorded.

RESULTS

Placental tissue was available for analysis in 95 of 171 infants evaluated (56%). Among these 95 infants, 34 had no cerebral abnormalities on MRI, 27 had white matter/watershed injury, 18 had BGT injury, and 16 had white matter/watershed injury with BGT involvement. Chorioamnionitis was a common placental finding in both the infants without injury (59%) and those with white matter/BGT injury (56%). On multinomial logistic regression analysis, white matter/watershed injury with and without BGT involvement was associated with decreased placental maturation. Hypoglycemia was associated with an increased risk of the white matter/BGT injury pattern (OR,5.4; 95% CI, 1.4-21.4). The BGT injury pattern was associated with chronic villitis (OR, 12.7; 95% CI, 2.4-68.7). A placental weight <10th percentile appeared to be protective against brain injury, especially for the BGT pattern (OR, 0.1; 95% CI, 0.01-0.7).

CONCLUSION

Placental weight <10th percentile was mainly associated with normal cerebral MRI findings. Decreased placental maturation and hypoglycemia <2.0 mmol/L were associated with increased risk of white matter/watershed injury with or without BGT involvement. Chronic villitis was associated with BGT injury irrespective of white matter injury.

Computerized assessment of placental calcification post-ultrasound: a novel software tool

OBJECTIVES

Placental calcification is associated with an increased risk of perinatal morbidity and mortality. The subjectivity of current ultrasound methods of assessment of placental calcification indicates that a more objective method is required. The aim of this study was to correlate the percentage of calcification defined by the clinician using a new software tool for calculating the extent of placental calcification with traditional ultrasound methods and with pregnancy outcome.

METHODS

Ninety placental images were individually assessed. An upper threshold was defined, based on high intensity, to quantify calcification within the placenta. Output metrics were then produced including the overall percentage of calcification with respect to the total number of pixels within the region of interest. The results were correlated with traditional ultrasound methods of assessment of placental calcification and with pregnancy outcome.

RESULTS

The results demonstrate a significant correlation between placental calcification, as defined using the software, and traditional methods of Grannum grading of placental calcification. Whilst correlation with perinatal outcome and cord pH was not significant as a result of small numbers, patients with placental calcification assessed using the computerized software at the upper quartile had higher rates of poor perinatal outcome when compared with those at the lower quartile (8/22 (36%) vs 3/23 (13%); P = 0.069).

CONCLUSION

These results suggest that this computerized software tool has the potential to become an alternative method of assessing placental calcification.

Delayed villous maturation of the placenta: quantitative assessment in different cohorts

Placental villous maturation is maximal in the 3rd trimester, with an abundance of terminal villi. Delayed villous maturation (DVM) of the placenta is associated with chromosomal abnormalities, gestational diabetes, and an adverse outcome. This study compares quantitative assessment of vasculo-syncytial membranes (VSM) in cases of liveborn infants, perinatal deaths, and controls. Cases were selected as follows: (1) liveborn infants with a qualitative diagnosis of DVM (n  =  15); (2) controls matched for gestational age whose placentas did not have DVM (n  =  15); (3) stillbirths (SB)/neonatal deaths (NND) showing DVM (n  =  13); and (4) SB from autopsies in which DVM was felt to be the cause of death (COD) (n  =  12). Vasculo-syncytial membranes were counted in 10 terminal villi in each of 10 consecutive high-power fields on 3 slides. Data analysis was carried out using SPSS. Liveborn cases with DVM showed statistically significantly less VSM than controls (mean 1.01 vs 2.42, P < 0.0001). The SB/NND group also showed significantly less VSM than the control group (mean 0.46 vs 2.42, P < 0.0001) and less than the liveborn DVM group (mean 0.46 vs 1.01, P  =  0.001). The COD group was significantly different from the control group (mean 0.42 vs 2.42, P < 0.0001) and the liveborn DVM group (mean 0.42 vs 1.01, P < 0.0001) but not significantly different from the SB/NND group. There is a quantitative reduction in VSM in cases of DVM compared to controls.

A new, clinically oriented, unifying and simple placental classification system

OBJECTIVE

At present there is no internationally accepted, clinically easy understandable, comprehensive morphological placental classification. This hampers international benchmarking and comparisons, and clinical research.

STUDY DESIGN

Internationally published criteria on morphological placental pathology were collected, standardized and focused into a comprehensive diagnosis category system. The idea was to create a clinically relevant placental pathology scheme related to major pathological processes. A system of nine main diagnostic categories (normal placenta included) was constructed. Pathologists and obstetricians discussed the mutual understanding of the wording in the reporting. The previously published diagnostic criteria were merged, structured and standardized. Through an interobserver correlation study on 315 placentas from intrauterine deaths and 31 controls (placentas from live births) the microscopic criteria in this classification system were tested on user-friendliness and reproducibility.

RESULTS

The clinical feedback has been very positive, focusing on the understandability and usefulness in patient follow-up. The interobserver agreement in the microscopic correlation study was in general good. The differences in agreement mainly reflected the degree of preciseness of the microscopic criteria, exemplified by excellent correlation in diagnosing acute chorioamnionitis. Maternal and fetal circulatory disorders need grading criteria and studies are needed to get more insight and clinical correlations of villitis and maturation disorders.

CONCLUSION

The clinically oriented, unifying and simple placental pathology classification system may work as a platform for standardization and international benchmarking. Further research is needed to define diagnostic criteria in staging and grading of some main diagnostic categories.

Clinical and ultrasound features of placental maturation in pre-gestational diabetic pregnancy

BACKGROUND

Pre-gestational diabetes (PGDM) is a significant cause of neonatal morbidity and mortality. Delayed villous maturation (DVM) is a placental diagnosis with increased risk of perinatal mortality.

AIMS

This study aimed to prospectively look at the incidence of DVM in a PGDM population compared to non-diabetic controls. Additionally, we analysed antenatal ultrasound and clinical markers for DVM in the diabetic population.

STUDY DESIGN

This is a prospective study.

SUBJECTS

Placentae of women with non-diabetic and PGDM pregnancies underwent detailed blinded histo-pathological examination.

OUTCOME MEASURES

Clinical data, including birth weight, peri-natal outcome, and, in PGDM group, glycaemic control and ultrasound findings, were obtained.

RESULTS

77 non-diabetic women and 74 PGDM women consented to the study. The incidence of DVM in the PGDM group was higher than in the non-diabetic group (21/74 (28.4%) vs. 11/77 (14.3%) p=0.02; RR 1.98). In the PGDM group clinical and ultrasound markers were compared between the DVM group (n=21) and the non-DVM group (n=53). There was no difference in perinatal outcome nor glycaemic control between these two groups.

CONCLUSION

DVM, a placental finding with an increased risk of perinatal mortality, is increased in PGDM population compared to non-diabetic controls. No association was found with maternal glycaemic control. The presence of placental DVM was not associated with antenatal ultrasound parameters nor clinical perinatal outcome.

Antenatal suspicion of ischemic placental disease and coexistence of maternal and fetal placental disease: analysis of over 500 cases

OBJECTIVE

To investigate the antenatal suspicion of placental disease and the coexistence of maternal and fetal placental ischemic disease.

STUDY DESIGN

A prospective cohort study on normally formed singleton infants from 2000 to 2008 inclusive with placental ischemic disease.

RESULTS

Uteroplacental ischemia or fetoplacental thrombotic vasculopathy was identified in 511 of 74,857 births (7/1000 births). Four hundred fifty-nine cases met the inclusion criteria. Maternal and fetal placental vascular disease coexisted in 9.2% (n = 42) of cases. Placental ischemic disease was suspected antenatally in 70% (324/459). Maternal placental disease occurred in 40% (184/459) and 30% (140/459) had fetal pathology. The perinatal mortality rate was 12.7/1000. Antenatal suspicion of placental disease led to increased obstetric intervention and delivery of small-for-gestational age infants.

CONCLUSION

Maternal and fetoplacental vascular disease coexisted in 9.2%. Placental disease was suspected antenatally in 70% of cases and was associated with increased rates of obstetric intervention.