Placental pathology, perinatal death, neonatal outcome, and neurological development: a systematic review

Placental histologic patterns and neonatal seizure, in preterm premature rupture of membrane

OBJECTIVE

To investigate the relationship between placenta and perinatal outcomes, in preterm infants born to mothers with preterm premature rupture of fetal membrane (PPROM).

METHODS

We report detailed histology of placentas and perinatal outcomes of infants from 79 PPROM pregnancies. Placental histologic pattern and adverse perinatal outcomes were assessed by logistic regression, adjusting for gestational age at birth, birth weight and interval from rupture of membrane to delivery.

RESULTS

Mean gestational age at membrane rupture was 29.5 ± 3.4 weeks. The incidence of histologic chorioamnionitis (HCA), fetal inflammatory response (FIR) and vascular thrombotic abnormalities in placental histologic examination were 63.3, 25.3 and 78.5%, respectively. Neonates with FIR showed significantly higher incidence of periventricular leukomalacia (PVL) (85% versus 59.3%, p = 0.0364) at brain ultrasonography, than neonates without FIR, in univariate analysis, but not in logistic regression analysis. In logistic regression analysis, the odds ratio of low Apgar score at 1 min in the neonates with clinical chorioamnionitis was 5.009 (95% CI, 1.242-20.195). The odds ratio of neonatal seizure in the neonates with FIR and vascular thrombotic problem was 7.486 (95% CI, 1.617-34.653).

CONCLUSIONS

Our findings support the association between FIR with vascular thrombotic problem in placenta and neonatal seizure, in pregnancies with PPROM.

Maternal plasma angiogenic index-1 (placental growth factor/soluble vascular endothelial growth factor receptor-1) is a biomarker for the burden of placental lesions consistent with uteroplacental underperfusion: a longitudinal case-cohort study

BACKGROUND

Placental lesions consistent with maternal vascular underperfusion (MVU) are thought to be pathogenically linked to preeclampsia, small-for-gestational-age newborns, fetal death, and spontaneous preterm labor and delivery; yet, these lesions cannot be diagnosed antenatally. We previously reported that patients with such conditions and lesions have an abnormal profile of the angiogenic placental growth factor (PlGF) and antiangiogenic factors (eg, soluble vascular endothelial growth factor receptor [sVEGFR]-1).

OBJECTIVE

The objectives of this study were to: (1) examine the relationship between the maternal plasma PlGF/sVEGFR-1 concentration ratio (referred to herein as angiogenic index-1) and the burden of histologic placental features consistent with MVU; and (2) test the hypothesis that angiogenic index-1 can identify patients in the midtrimester who are destined to deliver before 34 weeks of gestation with multiple (ie, ≥3) histologic placental features consistent with MVU.

STUDY DESIGN

A 2-stage case-cohort sampling strategy was used to select participants from among 4006 women with singleton gestations enrolled from 2006 through 2010 in a longitudinal study. Maternal plasma angiogenic index-1 ratios were determined using enzyme-linked immunosorbent assays. Placentas underwent histologic examination according to standardized protocols by experienced pediatric pathologists who were blinded to clinical diagnoses and pregnancy outcomes. The diagnosis of lesions consistent with MVU was made using criteria proposed by the Perinatal Section of the Society for Pediatric Pathology. Weighted analyses were performed to reflect the parent cohort; "n*" is used to reflect weighted frequencies.

RESULTS

(1) Angiogenic index-1 (PlGF/sVEGFR-1) concentration ratios were determined in 7560 plasma samples collected from 1499 study participants; (2) the prevalence of lesions consistent with MVU was 21% (n* = 833.9/3904) and 27% (n* = 11.4/42.7) of women with ≥3 MVU lesions delivered before 34 weeks of gestation; (3) a low angiogenic index-1 (<2.5th quantile for gestational age) in maternal plasma samples obtained within 48 hours of delivery had a sensitivity of 73% (n* = 8.3/11.4; 95% confidence interval [CI], 47-98%), a specificity of 94% (n* = 3130.9/3316.2; 95% CI, 94-95%), a positive likelihood ratio of 12.2, and a negative likelihood ratio of 0.29 in the identification of patients who delivered placentas with ≥3 MVU lesions at <34 weeks; (4) prospectively, at 20-23 weeks of gestation, a maternal plasma concentration of angiogenic index-1 <2.5th quantile identified 70% (n* = 7.2/10.3; 95% CI, 42-98%) of patients who delivered placentas with ≥3 MVU lesions before 34 weeks (specificity, 97% [n* = 2831.3/2918; 95% CI, 96-98%]; positive likelihood ratio, 23; negative likelihood ratio, 0.31); and (5) among women without obstetrical complications who delivered at term, angiogenic index-1 was lower in women with than without placental lesions consistent with MVU (P < .05).

CONCLUSION

Maternal plasma angiogenic index-1 (PlGF/sVEGFR-1) is the first biomarker for the burden of placental lesions consistent with MVU. We propose that an accumulation of these lesions in placentas delivered before 34 weeks is a histologic counterpart of an antiangiogenic profile.

Isolated Placental Inflammation and Vasculopathy: Clinical Implications in the Extremely Low Birth Weight Infants

The predictive values of placental histopathologies are compromised by a non-segregation of common anomalies. The effects of isolated pure placental inflammation (PI) and vasculopathy-coagulopathy (PV) were compared with normal (NL) placentas in extremely premature infants (ELBW, birth weight < 1000 g). PI infants required lower peak inspiratory pressure on day 3. More infants in PV were oxygen dependence on day 28. PV had an increased risk of intraventricular-periventricular hemorrhage (IVH, OR 4.9, 95% CI 1-24.7, p = 0.05). NL infants were unexposed to PPROM or maternal hypertension, had highest requirement for surfactant, did not develop IVH and periventricular leukomalacia (PVL) and none of them were Caucasian.

CONCLUSIONS

In ELBW infants (1) pure placental vasculopathy-coagulopathy is a risk factor for IVH, (2) a non- pathological intrauterine environment is nonconducive to IVH and PVL, (3) pure placental inflammation is protective for acute pulmonary disease, (4) Caucasian mothers are more susceptible to adverse intrauterine environment.

Decrease in Sphingomyelin (d18:1/16:0) in Stem Villi and Phosphatidylcholine (16:0/20:4) in Terminal Villi of Human Term Placentas with Pathohistological Maternal Malperfusion

Placental villi play pivotal roles in feto-maternal transportation and phospholipids constitute a major part of the villous membrane. We have been developing and optimizing an imaging system based on a matrix-assisted laser desorption/ionization (MALDI)-based mass spectrometer, which provides clear two-dimensional molecular distribution patterns using highly sensitive mass spectrometry from mixtures of ions generated on tissue surfaces. We recently applied this technology to normal human uncomplicated term placentas and detected the specific distribution of sphingomyelin (SM) (d18:1/16:0) in stem villi and phosphatidylcholine (PC) (16:0/20:4) in terminal villi. In the present study, we applied this technology to nine placentas with maternal or fetal complications, and determined whether a relationship existed between these specific distribution patterns of phospholipid molecules and the six representative pathological findings of placentas, i.e., villitis of unknown etiology (VUE), thrombus, atherosis, chorioamnionitis (CAM), immature terminal villi, and multiple branched terminal villi. In two placentas with the first and second largest total number of positive pathological findings, i.e., five and three positive findings, the specific distribution of SM (d18:1/16:0) in stem villi and PC (16:0/20:4) in terminal villi disappeared. The common pathological findings in these two placentas were atherosis, immature terminal villi, and multiple branched terminal villi, suggesting the possible involvement of the underperfusion of maternal blood into the intervillous space. On the other hand, the number of pathological findings were two or less in the seven other placentas, in which no specific relationships were observed between the differential expression patterns of these two phospholipids in stem and terminal villi and the pathological findings of the placentas; however, the specific distribution pattern of SM (d18:1/16:0) in stem villi disappeared in four placentas, while that of PC (16:0/20:4) in terminal villi was preserved. These results suggested that the absence of the specific distribution of PC (16:0/20:4) in terminal villi, possibly in combination with the absence of SM (d18:1/16:0) in stem villi, was linked to placental morphological changes in response to maternal underperfusion of the placenta.

Anomalies of the placenta and umbilical cord in twin gestations

The frequency of twin gestations has increased over the last few decades, mainly due to maternal age at childbearing, and the use of assisted reproductive technologies. Twins are at higher risk of aneuploidy, structural anomalies, and placental abnormalities. Some of the placental and umbilical cord abnormalities found in twin gestations are nonspecific and can be found in singleton gestations (ie, placenta previa, placental abruption, single umbilical artery, velamentous cord insertion, vasa previa, etc). However, other anomalies are unique to twin gestations, and are mainly associated with monochorionic twins-these include intraplacental anastomosis and cord entanglement. Most of these conditions can be diagnosed with ultrasound. An accurate and early diagnosis is important in the management of twin gestations. Determination of chorionicity, amnionicity, and the identification of placental anomalies are key issues for the adequate management of twin pregnancies. Pathologic placental examination after delivery can help in assessing the presence of placental and umbilical cord abnormalities, as well as providing information about chorionicity and gaining insight into the potential mechanisms of disease affecting twin gestations.

A clinicopathological study of episomal papillomavirus infection of the human placenta and pregnancy complications

Viral infections are known to adversely affect pregnancy, but scant attention has been given to human papilloma virus (HPV) infection. We aimed to determine the molecular and histopathological features of placental HPV infection, in association with pregnancy complications including fetal growth restriction, pre-maturity, pre-eclampsia, and diabetes. Three hundred and thirty-nine placentae were selected based on the presence or absence of pregnancy complications. Five independent methods were used to identify HPV in the placenta, namely, immunohistochemistry for L1 viral capsid, in situ hybridization to high-risk HPV DNA, PCR, western blotting, and transmission electron microscopy. Pregnancy complications and uterine cervical smear screening results were correlated with placental HPV histopathology. In this study, which was deliberately biased towards complications, HPV was found in the decidua of 75% of placentae (253/339) and was statistically associated with histological acute chorioamnionitis (P<0.05). In 14% (35/253) of the HPV positive cases, HPV L1 immunoreactivity also occurred in the villous trophoblast where it was associated with a lymphohistiocytic villitis (HPV-LHV), and was exclusively of high-risk HPV type. HPV-LHV significantly associated with fetal growth restriction, preterm delivery, and pre-eclampsia (all P<0.05). All cases of pre-eclampsia (20/20) in our cohort had high-risk placental HPV. A further 55 cases (22%, 55/253) of HPV positive placentae had minimal villous trophoblast HPV L1 immunoreactivity, but a sclerosing pauci-immune villitis, statistically associated with diabetes (49.1%, 27/55, P<0.05). For women with placental HPV, 33% (69/207) had an HPV-related positive smear result before pregnancy compared with (9.4% 8/85) of women with HPV-negative placentae (P=0.0001). Our findings support further investigations to determine if vaccination of women and men will improve pregnancy outcomes.

Antecedents of the child behavior checklist-dysregulation profile in children born extremely preterm

OBJECTIVE

Extremely preterm newborns are at heightened risk for emotional and behavioral dysregulation later in childhood. Our goal was to systematically evaluate the antenatal and early postnatal antecedents that might mediate the association between extreme preterm birth and emotional and behavioral dysregulation at age 2 years (corrected age).

METHOD

In a multi-site prospective study, the parents of 826 infants born before 28 weeks gestation completed a Child Behavior Checklist (CBCL) when the child was 2 years corrected age. We compared the maternal, pregnancy, placenta, delivery, and newborn characteristics, as well as early postnatal characteristics and exposures of those who satisfied criteria for the CBCL-Dysregulation Profile (CBCL-DP) to those of their peers. We then used time-oriented logistic regression models, starting first with antenatal variables that distinguished children with the CBCL-DP profile from their peers, and then added the distinguishing postnatal variables.

RESULTS

Approximately 9% of the children had a CBCL-DP. In the time-oriented logistic regression model with antenatal variables only, low maternal education achievement, passive smoking, and recovery of Mycoplasma from the placenta were associated with increased risk, whereas histologic chorioamnionitis was associated with reduced risk. None of the postnatal variables added statistically significant discriminating information.

CONCLUSION

Very preterm newborns who later manifest the CBCL-DP at age 2 years differ in multiple ways from their preterm peers who do not develop the CBCL-DP, raising the possibility that potentially modifiable antenatal and early postnatal phenomena contribute to the risk of developing emotional and behavioral dysregulation.

Placenta with Old, Diffuse Infarction that Was Difficult to Differentiate from a Placental Tumor

Placental lesions, including placental infarction, are associated with fetal and neonatal mortality and morbidity. We present a case of fetal growth restriction associated with an old, diffuse placental infarction. Because the placenta had only a single viable cotyledon, the others being atrophic, the lesion appeared to be a placental tumor on prenatal ultrasonography. The patient did not have pregnancy-induced hypertension. At 31 weeks of gestation, a cesarean delivery was performed because of fetal growth arrest and breech presentation. A small-for-gestational age infant was delivered with Apgar scores of 8 at both 1 and 5 minutes, and the infant had cleft palate and cleft lips. Pathological examination of the placenta revealed an old, diffuse infarction without neoplastic change. In cases in which a placental tumor causing fetal growth restriction is strongly suspected, diffuse placental infarction should be considered as part of the differential diagnosis, because placental tumors are associated with poor maternal prognosis.

Investigating the effect of excess caffeine exposure on placental angiogenesis using chicken 'functional' placental blood vessel network

It is now known that over-consumption of caffeine by pregnant mothers could have detrimental effects on normal fetal development. However, it remains obscure how caffeine's harmful effect impacts directly or indirectly on the developing embryo/fetus through damaging placenta development. In this study, we demonstrated the morphological similarities between the yolk sac and chorioallantoic membranes (CAM) of chick embryos and the villi of the mammalian placenta. Using the chick yolk sac and the CAM as a model, we found that 5-15 µmol per egg of caffeine exposure inhibited angiogenesis. Under the same condition, cell proliferation in extraembryonic mesoderm was reduced while apoptosis was enhanced. Semi-quantitative RT-PCR analysis revealed that caffeine treatment down-regulated VEGF, VEGFR2, PIGF, IGF2 and NRP1 expression, but up-regulated Ang1 and Ang2 expression. We performed in situ hybridization to show VE-cadherin expression and as to demonstrate the blood vessels in the CAM and yolk sac membranes. This distribution of the VE-cadherin(+) blood vessels was determined to be reduced after caffeine treatment. Furthermore, MDA activity was induced after caffeine exposure, but GSH-PX activity was inhibited after caffeine exposure; SOD activity was unchanged as compared with the control. In summary, our results suggest that caffeine exposure could negatively impact on angiogenesis in the chick yolk sac and CAM by targeting angiogenesis-related genes. Some of these genes are also involved in regulating excess ROS generation. The results implied that the negative impact of caffeine on fetal development was partly attributed to impaired placental angiogenesis.

Neonatal hypertonia - a diagnostic challenge

In comparison to hypotonia, hypertonia is less commonly expressed in the neonatal period. The scientific literature on the causes of neonatal hypertonia is scant, with no suggested diagnostic algorithm easily available to clinicians. Aetiologies include conditions affecting the central nervous system and spine, and rare peripheral neuromuscular disorders leading to hypertonia. Aetiology onset may be antepartum, peripartum with either transient hypertonia or persistent hypertonia which may appear later, or from a postnatal event/disease. This review discusses neonatal hypertonia and a diagnostic approach to neonatal hypertonia is suggested.

Placental pathology in asphyxiated newborns treated with therapeutic hypothermia

OBJECTIVE

To describe the placental findings in asphyxiated newborns treated with hypothermia and to determine their association with the presence and severity of later brain injury.

METHODS

Prospective cohort study of the placentas of asphyxiated newborns treated with hypothermia, in whom later brain injury was defined by brain imaging and/or autopsy results.

RESULTS

Of the 142 asphyxiated newborns meeting the criteria for hypothermia, 73% had placenta and brain MRI/autopsy available for analysis. Fifty-one percent of these newborns developed brain injury. Sixty-five percent had microscopic placental findings involving the fetal vascular supply, which were comparable in asphyxiated newborns developing or not developing brain injury. Among the asphyxiated newborns with normal placental growth, the placental microscopic findings tended to be more common in those developing brain injury compared to those who did not: chorionic plate meconium in 50% compared to 36%, chorioamnionitis in 75% compared to 44%, and villitis of unknown etiology in 67% compared to 33%, but this did not reach statistical significance.

CONCLUSIONS

Antenatal placental processes are common in term asphyxiated newborns treated with hypothermia. The placenta of each asphyxiated term newborn treated with hypothermia should be carefully examined to better understand its role in the progression from perinatal depression to brain injury.

Hypoxic ischemic encephalopathy in newborns linked to placental and umbilical cord abnormalities

OBJECTIVE

Birth asphyxia and hypoxic ischemic encephalopathy (HIE) of the newborn remain serious complications. We present a study investigating if placental or umbilical cord abnormalities in newborns at term are associated with HIE.

MATERIALS AND METHODS

A prospective cohort study of the placenta and umbilical cord of infants treated with hypothermia (HT) due to hypoxic brain injury and follow-up at 12 months of age has been carried out. The study population included 41 infants treated for HT whose placentas were submitted for histopathological analysis. Main outcome measures were infant development at 12 months, classified as normal, cerebral palsy, or death. A healthy group of 100 infants without HIE and normal follow-up at 12 months of age were used as controls.

RESULTS

A velamentous or marginal umbilical cord insertion and histological abruption was associated with the risk of severe HIE, OR = 5.63, p = 0.006, respectively, OR = 20.3, p = 0.01 (multiple-logistic regression). Velamentous or marginal umbilical cord insertion was found in 39% among HIE cases compared to 7% in controls.

CONCLUSIONS

Placental and umbilical cord abnormalities have a profound association with HIE. A prompt examination of the placentas of newborns suffering from asphyxia can provide important information on the pathogenesis behind the incident and contribute to make a better early prognosis.

Do Placental Histopathologic Characteristics Differ with Gestational Ages in Preterm and Term Deliveries?

The study aim is to evaluate the placental histopathological characteristics and maternal risk factors in preterm and term births according to their weeks of gestation. We designed a prospective study involving a patient population (n = 355) composed of pregnant women who delivered preterm (n = 216) and term neonates (n = 139). The preterm births were divided into three groups as extremely (n = 22), moderate (n = 96) and late preterm (n = 98) births. The statistical analyses were performed using SPSS version 15 software. There was significant difference regarding maternal vascular underperfusion and inflammation in the extremely preterm group compared with the other groups (P = 0.001), but fetal vascular obstruction and villitis of unknown etiology were not found significantly different. According to our study results, the careful examination of the placenta of premature babies, particularly those of extremely preterm births, should be part of routine obstetrical management to determine the causes of preterm birth.