Hypercoiling of the umbilical cord and placental maturation defect: associated pathology?

Placental Pathology Contributes to Impaired Volumetric Brain Development in Neonates With Congenital Heart Disease

BACKGROUND

Neonates with congenital heart disease are at risk for impaired brain development in utero, predisposing children to postnatal brain injury and adverse long-term neurodevelopmental outcomes. Given the vital role of the placenta in fetal growth, we assessed the incidence of placental pathology in fetal congenital heart disease and explored its association with total and regional brain volumes, gyrification, and brain injury after birth.

METHODS AND RESULTS

Placentas from 96 term singleton pregnancies with severe fetal congenital heart disease were prospectively analyzed for macroscopic and microscopic pathology. We applied a placental pathology severity score to relate placental abnormalities to neurological outcome. Postnatal, presurgical magnetic resonance imaging was used to analyze brain volumes, gyrification, and brain injuries. Placental analyses revealed the following abnormalities: maternal vascular malperfusion lesions in 46%, nucleated red blood cells in 37%, chronic inflammatory lesions in 35%, delayed maturation in 30%, and placental weight below the 10th percentile in 28%. Severity of placental pathology was negatively correlated with cortical gray matter, deep gray matter, brainstem, cerebellar, and total brain volumes (r=-0.25 to -0.31, all P<0.05). When correcting for postmenstrual age at magnetic resonance imaging in linear regression, this association remained significant for cortical gray matter, cerebellar, and total brain volume (adjusted R2=0.25-0.47, all P<0.05).

CONCLUSIONS

Placental pathology occurs frequently in neonates with severe congenital heart disease and may contribute to impaired brain development, indicated by the association between placental pathology severity and reductions in postnatal cortical, cerebellar, and total brain volumes.

Comparison of the Autopsy and Placental Findings in Second vs Third Trimester Stillbirth

BACKGROUND

The pathology of second trimester fetal loss is not well-characterized due to lack of comprehensive autopsy studies. The purpose of this study is to compare autopsy pathology of second trimester and third trimester stillbirth.

METHODS

In this retrospective cohort study, fetal autopsies performed in-house with complete placental examination were included. From autopsy reports, maternal demographics, gestational age, sex, body and placental weight, congenital anomalies, and cause of death (COD) were obtained. Immediate COD was coded "probable" or "possible" according to Initial Causes of Fetal Death (INCODE).

RESULTS

Among 68 second trimester and 54 third trimester fetal autopsies, at least 1 probable COD was identified in 59/68 (87%) second trimester and 44/54 (81%) third trimester cases. 42/68 (62%) second trimester and 28/54 (52%) third trimester fetuses had probable COD secondary to placental pathology. Among placental causes, 29/42 (69%) second trimester and 14/28 (50%) third trimester stillbirths were related to compromised fetal microcirculation with umbilical cord abnormality.

CONCLUSIONS

Among stillborn first and second trimester fetuses who undergo autopsy, the most prevalent COD is pathologic placental conditions, particularly those associated with umbilical cord obstruction. This study stresses the importance of placenta examination for establishing COD in both second and third trimester fetuses.

Erythroblasts in the Vessels of the Placenta – An Independent Factor of Chronic Hypoxic Damage to the Fetus

The aim is a comparative histological study of the relative number of fetal erythroblasts in the vessels of the placentas from a full term pregnancy with a low and high risk of fetal hypoxic damage. Material and methods. Based on data on the course of pregnancy, the state of health of the mother and the fetus/newborn, as well as histological examination of the placenta, 388 archived placenta tissue samples were selected in 2 groups: a high risk group for chronic hypoxic damage to the fetus and a group without clinical and laboratory signs of fetal/newborn hypoxia. The relationship between the number of erythroblasts in the vessels of the placenta and chronic hypoxic damage to the fetus was analyzed. Results: The high risk of chronic hypoxic fetal damage is higher for placentas with ≥8 fetal erythroblasts in chorionic villi vessels (OR=3.175; 95% CI =1.921-5.248, p<0.001), with maternal vascular malperfusion (OR=2.798; 95% CI = 1.506-5.164, p=0.001) and combined (cross) placental lesions (OR=2.245; 95%CI=1.246-4.046, p =0.007) with damage of ≥30% of placental tissue. Conclusion: 8 or more fetal erythroblasts in the lumen of the vessels of the placenta is an additional independent factor in chronic hypoxic damage to the fetus. These results are of practical importance for identifying a group of newborns with a high risk of chronic hypoxic damage in the perinatal period and stratification of the risk group in the postnatal period in order to reduce infant morbidity and mortality.  

FIGO (international Federation of Gynecology and obstetrics) initiative on fetal growth: best practice advice for screening, diagnosis, and management of fetal growth restriction

Fetal growth restriction (FGR) is defined as the failure of the fetus to meet its growth potential due to a pathological factor, most commonly placental dysfunction. Worldwide, FGR is a leading cause of stillbirth, neonatal mortality, and short- and long-term morbidity. Ongoing advances in clinical care, especially in definitions, diagnosis, and management of FGR, require efforts to effectively translate these changes to the wide range of obstetric care providers. This article highlights agreements based on current research in the diagnosis and management of FGR, and the areas that need more research to provide further clarification of recommendations. The purpose of this article is to provide a comprehensive summary of available evidence along with practical recommendations concerning the care of pregnancies at risk of or complicated by FGR, with the overall goal to decrease the risk of stillbirth and neonatal mortality and morbidity associated with this condition. To achieve these goals, FIGO (the International Federation of Gynecology and Obstetrics) brought together international experts to review and summarize current knowledge of FGR. This summary is directed at multiple stakeholders, including healthcare providers, healthcare delivery organizations and providers, FIGO member societies, and professional organizations. Recognizing the variation in the resources and expertise available for the management of FGR in different countries or regions, this article attempts to take into consideration the unique aspects of antenatal care in low-resource settings (labelled “LRS” in the recommendations). This was achieved by collaboration with authors and FIGO member societies from low-resource settings such as India, Sub-Saharan Africa, the Middle East, and Latin America.

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.

Umbilical cord coiling index for the prediction of adverse pregnancy outcomes: a meta-analysis and sequential analysis

Purpose: To evaluate the potential association of abnormal cord coiling with adverse pregnancy outcomes.Materials and methods: We used the Medline (1966-2018), Scopus (2004-2018), Clinicaltrials.gov (2008-2018), Embase (1980-2018), Cochrane Central Register of Controlled Trials CENTRAL (1999-2018), and Google Scholar (2004-2018) databases. The date of last search was set on 31 May 2018. Language, country, or date restrictions were not applied during the literature research to prevent bias. All observational (both prospective and retrospective) studies that reported maternal and neonatal antenatal and perinatal outcomes based on the umbilical coiling index (UCI) status were considered as eligible for inclusion. Meta-analysis of the risk ratio (RR) and mean differences (MD) among hypocoiled/hypercoiled and normocoiled cases was performed with RevMan 5.3 software. Univariate metaregression and leave-one-out meta-analysis was performed with Open Meta-Analyst statistical software. Trial sequential analysis was performed with the trial sequential analysis (TSA) software.Results: Twenty four studies were finally included that involved 9553 pregnant women. Umbilical cord coiling was evaluated with the use of the umbilical coiling index (UCI). Values of the UCI below the 10th percentile were evaluated as hypocoiled and above the 90th percentile as hypercoiled. Hypocoiled cords were significantly associated with increased prevalence of preterm birth < 37 weeks, need for interventional delivery due to fetal distress, meconium stained liquor, Apgar scores < 7 at 5 min, small for gestational age (SGA) neonates, fetal anomalies, need for admission in the neonatal intensive care unit (NICU), fetal heart rate abnormalities, and fetal death. Hypercoiled cords were significantly associated with increased prevalence of preterm birth < 37 weeks, need for interventional delivery due to fetal distress, meconium stained liquor, Apgar scores < 7 at 5 min, small for gestational age (SGA) neonates, fetal anomalies, fetal growth restriction fetal heart rate abnormalities, fetal acidosis, and fetal death.Conclusions: The findings of our meta-analysis underline the correlation of UCI abnormalities with antenatal and perinatal pathology. More studies are needed, however, to elucidate whether antenatal assessment of the UCI can be used as routine in clinical practice as well as its value in uncomplicated pregnancies.

Histomorphological changes of the placenta and umbilical cord in pregnancies complicated by gestational diabetes mellitus

INTRODUCTION

The objective of this study was to compare the histomorphological changes of placenta and umbilical cord (UC), between gestational diabetes mellitus (GDM) and non- GDM pregnancies.

METHODS

In this prospective study, 222 parturients were recruited (117 GDM and 105 non-GDM). GDM was confirmed at 24-28 weeks of gestation, using one-step strategy. A full record of demographic, laboratory, histologic and gross morphology data of placenta and UC was extracted and analyzed.

RESULTS

Overall, 222 placentas/UCs met inclusion criteria. The mean (SD) of gestational age of GDM diagnosis was 20.68 (10.02) and the GDM duration was 16.76 (8.98) weeks. The mean HbA1C was 6.03 (0.41) % in the GDM group. The gross morphology findings including UC diameter and thick edematous UC differed significantly between two groups and more presented in GDM group, 1.41 (0.03) vs. 1.28 (0.03) centimeters; p-value = 0.006 and 34.19% vs. 16.19%; p-value = 0.002, respectively. The umbilical coiling index (UCI) was similar in two groups (p-value = 0.61). In the histological evaluation, persistence of central vessels differed significantly between two groups, more detected in non-GDM (47.62% vs. 32.97%; p-value = 0.04). No other significant histomorphological changes were detected between two groups.

DISCUSSION

This study showed that gross morphologic features such as UC diameter increment and thick edematous UC happened more frequently, among the GDM parturients. Due to early diagnosis, diagnosis strategy, and optimal glycemic control, the histomorphological changes were less in GDM comparing of non-GDM group.

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.

Excessive umbilical cord coiling confers risk of elevated nocturnal blood pressure and severe/early-onset preeclampsia

BACKGROUND

The associations between umbilical cord coiling, feto-placental vascular resistance and maternal blood pressure (BP) are not well understood.

METHOD

We retrospectively analyzed 502 pregnant women suspected of hypertensive disorders in the third trimester from a hospital-based cohort, who underwent ambulatory BP monitoring and umbilical artery Doppler velocimetry examinations within 14 days before delivery. By applying quantile regression, a significant quantile-dependent positive association between umbilical cord coiling index and umbilical artery pulsatility index (UAPIMOM; converted to multiples of median) was observed from above 0.75th quantiles for each parameter.

RESULTS

Using the cutoffs both at the 0.75th quantile to define high umbilical cord coiling (≥0.28 coils/cm) and high UAPIMOM (≥1.30), respectively, a graded increase in BP level was observed from patients with both low, either high and both high categories. Multivariate linear and quantile regression revealed that the high umbilical cord coiling/high UAPIMOM interaction was significantly correlated with night-time mean DBP level. Moreover, umbilical cord hypercoiling (≥0.3 coils/cm) was significantly correlated with night-time DBP with an average increase of ∼5 mmHg from the 0.05th to 0.70th quantiles and independently predicted the occurrence of severe (odds ratio 2.32, 95% confidence interval: 1.22-4.41) and early-onset (odds ratio 2.43, 95% confidence interval: 1.18-4.97) preeclampsia after adjusting for covariates. Further mediation analysis showed that elevated high UAPIMOM (≥1.30) could explain 11.4% of the umbilical cord hypercoiling → high night-time DBP association.

CONCLUSION

Therefore, this retrospective study identifies excessive umbilical cord coiling, and its interaction with increased feto-placental vascular resistance, as novel risk factors for nocturnal BP elevation and preeclampsia.

Placental Histology After Minor Trauma in Pregnancy: A Pilot Study

OBJECTIVE

Trauma in pregnancy may cause placental abruption. Consequences of moderate placental injury on neurodevelopment are unknown. The aim was to evaluate placental histology after maternal trauma.

METHODS

A prospective study was conducted at 2 tertiary medical centers in the Netherlands. Placentas from women exposed to maternal trauma ≥ 20 weeks' gestational age were histologically examined. Neurological follow-up of the infants was performed at 1 year of age by means of Alberta Infant Motor Scale. Histological findings were compared to placentas from pregnancies without trauma.

PRINCIPAL RESULTS

Thirteen placentas were investigated in the trauma group. The control group consisted of 15 placentas. Placental pathology was seen more often in the trauma cases (11 of the 13) than in the controls (6 of the 15), P = .024. Neurological follow-up was normal.

CONCLUSIONS

In this small population, majority of the placentas showed pathology after minor trauma in pregnancy without consequences for neurodevelopment at 1 year.

Fetal vascular malperfusion, an update

Fetal vascular malperfusion is the most recent term applied to a group of placental lesions indicating reduced or absent perfusion of the villous parenchyma by the fetus. The most common etiology of malperfusion is umbilical cord obstruction leading to stasis, ischemia, and in some cases thrombosis. Other contributing factors may include maternal diabetes, fetal cardiac insufficiency or hyperviscosity, and inherited or acquired thrombophilias. Severe or high grade fetal vascular malperfusion is an important risk factor for adverse pregnancy outcomes including fetal growth restriction, fetal CNS injury, and stillbirth. Overall recurrence risk for subsequent pregnancies is low.

Placental examination in nonmacerated stillbirth versus neonatal mortality

AIM

To retrospectively statistically compare clinical and placental phenotypes of nonmacerated fetuses and live-born perinatal deaths in 3rd trimester pregnancies.

METHODS

Twenty-five clinical and 47 placental phenotypes were statistically compared among 93 cases of nonmacerated (intrapartum, or recent antepartum death) 3rd trimester fetal deaths (Group 1), 118 3rd trimester neonatal deaths (Group 2) and 4285 cases without perinatal mortality (Group 3).

RESULTS

Sixteen clinical and placental phenotypes were statistically significantly different between Group 3 and the two groups of perinatal deaths, which included eight placental phenotypes of fetal vascular malperfusion and eight other placental phenotypes of various etiology (amnion nodosum, 2-vessel umbilical cord, villous edema, increased extracellular matrix of chorionic villi, erythroblasts in fetal blood and trophoblastic lesions of shallow placentation). Statistically significant differences between Groups 1 and 2 were scant (oligohydramnios, fetal malformations, cesarean sections, hypercoiled umbilical cord and amnion nodosum being more common in the latter, and retroplacental hematoma more common in the former).

CONCLUSION

Placental examination in neonatal mortality shows thrombotic pathology related to umbilical cord compromise and features of shallow placental implantation that are similar to those in nonmacerated stillbirth; however, the features of placental abruption were more common in recent antepartum death, as were the features related to neonatal congenital malformations in neonatal deaths.

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.

Association of coexisting morphological umbilical cord abnormality and clinical cord compromise with hypoxic and thrombotic placental histology

To assess the usefulness and limitations of placental histology when morphological umbilical cord (UC) abnormality coexists with clinical UC compromise, 5634 consecutive placentas were divided into four groups and statistically compared: group 1-182 placentas from pregnancies with clinical features of UC compromise (variable decelerations, UC entanglement, prolapse, or true knot at delivery); group 2-1355 placentas with abnormal UC morphology or insertion; group 3-152 placentas with at least one phenotype from group 1 and one from group 2; group 4-3945 placentas with no clinical or morphological UC-related phenotypes (control group).Differences were analyzed by ANOVA or χ (2). Of 68 phenotypes studied, 13 clinical and 18 placental phenotypes were statistically significant. In group 1, 2 phenotypes were most common (oligohydramnios and abnormal fetal heart rate tracing). In group 2, 6 phenotypes were most common, including 4 clinical (abnormal umbilical artery Dopplers, nonmacerated stillbirth, multiple pregnancy, and fetal growth restriction) and 2 placental. In group 3, 23 phenotypes were most common, including 7 clinical (gestational hypertension, polyhydramnios, induction of labor, cesarean section, macerated stillbirth, congenital malformations, and abnormal 3rd stage of labor) and 16 placental. The existence of clinical signs of UC compromise alone was associated with the absence of pathomorphological placental abnormalities. However, the coexistence of clinical and abnormal morphological UC phenotypes was statistically significantly associated with placental histological signs of decreased fetal blood flow, hypoxia (acute and chronic post uterine), shallow placental implantation, and/or amnion nodosum. Thus, confirmation of clinical UC compromise should not be expected on placental examination if no morphological UC abnormality or abnormal UC insertion has been found.

Placental characteristics in women with polycystic ovary syndrome

STUDY QUESTION

Are macroscopic and microscopic placental characteristics in a heterogeneous group of women diagnosed with polycystic ovary syndrome (PCOS) different from those of a low-risk general population?

SUMMARY ANSWER

Women with PCOS have significantly different microscopic placental characteristics compared with control women, independently from pregnancy complications.

WHAT IS KNOWN ALREADY

Non-obese women with PCOS who conceived spontaneously have a significantly reduced placental volume and weight, with more chronic villitis and intervillositis compared with healthy controls.

STUDY DESIGN, SIZE, DURATION

A subset of a large prospective cohort study of pregnant women with PCOS was used. Healthy (low-risk) women who delivered at term after an uncomplicated pregnancy were used as the reference population. The placentas of 73 women with PCOS were analysed and compared with 209 placentas of healthy women.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Placentas were collected after delivery from women with PCOS who were followed from prior to conception until delivery. The placentas were macroscopically and microscopically analysed and compared with placentas of healthy women with either a spontaneous start of labour who delivered at term or who had an elective Caesarean section.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjusting for potential confounders, placentas from women with PCOS showed more chorioamnionitis (P < 0.001), funisitis (P = 0.019), villitis (P = 0.045), thrombosis (P = 0.018), infarction (P = 0.010), villous immaturity (P = 0.009) and nucleated fetal red blood cells (P < 0.001). In a subgroup analysis, among women with and without pregnancy complications within the PCOS group, only the occurrence of thrombosis was increased in pregnancies complicated by pregnancy-induced hypertension or pre-eclampsia (30%, versus 0% in gestational diabetes pregnancies and 13% in uncomplicated pregnancies; P = 0.008).

LIMITATIONS, REASONS FOR CAUTION

There might be a small proportion of women with PCOS in the reference group, since this group was not screened for PCOS. As a result, the observed difference may be an underestimation of the true difference. Placentas were stored for up to 72 h at 4°C, this is common practice but some degenerative changes cannot be ruled out absolutely. Also, there is possibility that baseline differences between the groups may in part explain some of the differences in placental pathology.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings suggest that, in general, women with PCOS can have placental alterations associated with an increased hypoxic state, which seems not to be caused by the increased incidence of pregnancy complications.

Classification of placental lesions

Placental pathology can be useful in a variety of ways including immediate diagnosis of important conditions affecting the mother or infant, identifying conditions that are likely to recur in subsequent pregnancies, separating clinical syndromes into distinct pathological phenotypes for further investigation, and uncovering the underlying cause of unexpected adverse outcomes. Classification of placental lesions has evolved from being a purely descriptive exercise through a stage in which the major pathophysiological processes such as disorders of maternal implantation and the amniotic fluid infection syndrome were first described to a recently proposed comprehensive classification system that includes all of the major maternal and fetal vascular and infectious and idiopathic/immune inflammatory processes (Amsterdam Placental Workshop Group). Implementation of this unified system with reproducible grading and staging should help establish evidence-based recommendations for placental submission and facilitate progress in studying the pathogenesis, diagnosis, and treatment of obstetric disorders with an underlying placental etiology.

The clinical implications of placental diagnoses

The clinical utility of placental pathology is both overestimated and underestimated, and the overall quality of placental pathology reporting, even at major medical centers, is highly variable. Clear benefits of examining placentas include the immediate diagnosis of treatable conditions in both the mother and the infant, clarification of the underlying etiology of adverse pregnancy outcomes, estimation of recurrence risk, and guidance for the management of future pregnancies. In order to realize these benefits and get the most out of their pathology departments, it is critical for clinicians to understand the range and implications of placental lesions. This article will review the nomenclature, diagnostic criteria and pitfalls, and clinical significance of seven common placental disease processes and a handful of other lesions.

Umbilical hypercoiling in 2nd- and 3rd-trimester intrauterine fetal death

Cases of unexplained intrauterine fetal death (IUFD) can be reduced by full placental examination, with or without autopsy. Determination of the umbilical coiling index (UCI) is considered to be a part of full placental examination. Umbilical hypercoiling (UCI above 0.30 coils/cm) is associated with IUFD. In a large retrospective study, we found an incidence of 18% umbilical hypercoiling in IUFD. We explored the association between umbilical hypercoiling and 2nd- and 3rd-trimester IUFD in 77 cases. There was a significant negative correlation between the UCI and gestational age of IUFD (P<0.001). More severe cases of hypercoiling were observed in the categories of IUFD at a younger age and with a longer duration. Signs of fetal thrombosis were significantly more present in IUFDs with umbilical hypercoiling. An umbilical cord stricture and hypercoiling seem to be significantly more common in IUFD. The severity of hypercoiling was of no influence on the presence or absence of an umbilical cord stricture. Furthermore, there was no significant difference in signs of cardiac failure between the groups of IUFD with and without umbilical hypercoiling. Our findings may be explained by the theory that hypercoiling leads to a disturbed fetal-placental circulation. Therefore, determination of the UCI should be part of the routine placental examination of cases of IUFD.

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.

Evaluation of antenatal umbilical coiling index at 16-21 weeks of gestation as a predictor of trisomy 21 and other chromosomal defects

OBJECTIVES

To determine whether there is an association between sonographically assessed hyper- or hypocoiling of the umbilical cord and the presence of trisomy 21, to provide reference values for the antenatal umbilical coiling index (aUCI) at a gestational age of 16-21 weeks and to determine whether these measurements are reliable and reproducible.

METHODS

This was a prospective study of 737 pregnancies in which the aUCI was measured between 16 and 21 weeks of gestation by ultrasound at the time of amniocentesis. The aUCI was calculated as the reciprocal value of the mean length of one complete coil in centimeters. We created reference curves and studied the relationship with trisomy 21 and other chromosomal defects. In 30 pregnancies we studied the intra- and interobserver variation in measurements using Bland-Altman plots with associated 95% limits of agreement and intraclass correlation coefficients.

RESULTS

aUCI was found to be non-linearly related to gestational age at 16-21 weeks and reference curves were created for the mean aUCI and the 2.3(rd) , 10(th) , 90(th) and 97.7(th) percentiles. There was no significant difference in aUCI values between the reference group (n = 714) and cases with trisomy 21 (n = 16) or other aneuploidies (n = 7) (one-way ANOVA, P = 0.716). There was good intra- and interobserver agreement in aUCI measurements.

CONCLUSIONS

The aUCI can be measured reliably and varies according to gestational age at 16-21 weeks. The aUCI was not significantly associated with trisomy 21 or other chromosomal defects.

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.

Hypoxic patterns of placental injury: a review

CONTEXT

In utero hypoxia is an important cause of perinatal morbidity and mortality and can be evaluated retrospectively to explain perinatal outcomes, to assess recurrence risk in subsequent pregnancies, and to investigate for medicolegal purposes by identification of many hypoxic placental lesions. Definitions of some placental hypoxic lesions have been applied relatively liberally, and many of them are frequently underreported. Objectives To present a comprehensive assessment of the criteria for diagnosing acute and chronic histologic features, patterns, and lesions of placental and fetal hypoxia and to discuss clinicopathologic associations and limitations of the use thereof. The significance of lesions that have been described relatively recently and are not yet widely used, such as laminar necrosis; excessive, extravillous trophoblasts; decidual multinucleate extravillous trophoblasts; and, most important, the patterns of diffuse chronic hypoxic preuterine, uterine, and postuterine placental injury and placental maturation defect, will be discussed.

DATA SOURCES

Literature review.

CONCLUSIONS

The placenta does not respond in a single way to hypoxia, and various placental hypoxic features should be explained within a clinical context. Because the placenta has a large reserve capacity, hypoxic lesions may not result in poor fetal condition or outcome. On the other hand, very acute, in utero, hypoxic events, followed by prompt delivery, may not be associated with placental pathology, and many poor perinatal outcomes can be explained by an etiology other than hypoxia. Nevertheless, assessment of placental hypoxic lesions is helpful for retrospective explanations of complications in pregnancy and in medicolegal investigation.

Umbilical Cord Pathology

Problems and abnormalities of the umbilical cord play a significant role in perinatal morbidity and mortality. Because the umbilical cord is the lifeline of the fetus, any disruption of blood flow through the umbilical vessels can lead to severe fetal consequences.

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.

Correlation of Placental Pathology with Perinatal Brain Injury

The purpose of placental pathology is to explain adverse clinical outcomes. One of the most tragic of these outcomes is perinatal brain injury with subsequent neurodisability. Findings in the placenta can play an important role in documenting sentinel events, uncovering clinically silent thromboinflammatory disease processes, revealing developmental alterations in functional reserve, and suggesting alterations in related maternal and fetal physiology. These findings, when integrated with clinical data, provide a plausible explanation for an otherwise unexpected outcome and can be helpful for treating physicians and family members.

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.

Placental pathology and long-term neurodevelopment of very preterm infants

OBJECTIVE

The objective of the study was to compare neonatal morbidity and long-term neurodevelopmental outcome between very preterm infants with placental underperfusion and very preterm infants with histological chorioamnionitis.

STUDY DESIGN

We measured the mental and motor development at age 2 and 7 years in 51 very preterm infants with placental underperfusion and 21 very preterm infants with histological chorioamnionitis.

RESULTS

At 2 years, very preterm infants with placental underperfusion had poorer mental development than very preterm infants with histological chorioamnionitis (mean [SD] 90.8 [18.3] vs 104.1 [17.2], adjusted d = 1.12, P = .001). Motor development was not different between both groups (92.8 [17.2] vs 96.8 [8.7], adjusted d = 0.52, P = .12). At 7 years, large, although nonsignificant, effects were found for better mental and motor development and fewer behavioral problems in infants with histological chorioamnionitis.

CONCLUSION

Placental pathology contributes to variance in mental development at 2 years and should be taken into account when evaluating neurodevelopmental outcome of very preterm infants.

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

Delayed villous maturation (DVM) is a spectrum of placental disease characterized by decreased tertiary villus formation, reduced vasculosyncytial membrane formation, and, in its more severe forms, increased large bullous villi. In some series it has been associated with an increased risk of stillbirth in the late third trimester, but overall there are few data on its significance. The aim of this study was to assess perinatal factors associated with, and the clinical significance of, the finding of DVM on placental histology. This was a retrospective study investigating all pregnancies with DVM diagnosed on placental histology in a tertiary level unit between December 2001 and August 2006. Over a 6-year period, 2915 placentas were triaged for histopathological assessment, representing 6.1% of all 48 054 deliveries in this time period. One hundred ninety (6.3%) of these selected cases showed DVM. Fifteen placentas from infants with less than 34 completed weeks of gestation were excluded, leaving 175 for further analysis. When compared with controls matched for gestation and delivering within the same time period (n  =  175), DVM was significantly associated with pregestational diabetes (8% vs 2.8%, P < .05; relative risk 2.8 [95% confidence interval 1.03-7.6]), gestational diabetes (8.6% vs 3.4%, P < 0.05; relative risk 2.5 [95% confidence interval 0.99-6.3]), and prenatal or intrapartum intrauterine death (8.6% vs 0%, P < 0.05). Delayed villous maturation is associated with both gestational and pregestational diabetes mellitus and with perinatal death.

First trimester umbilical cord and vitelline duct measurements using virtual reality

BACKGROUND

the umbilical cord and vitelline duct are of vital importance to the fetus, but they are rarely the subject of first trimester two-dimensional (2D) ultrasound evaluation due to the complexity of their shape and morphology. Virtual reality (VR) allows efficient visualisation and measurement of complex structures like the umbilical cord and vitelline duct.

AIM

to measure normal first trimester human growth of the umbilical cord length (UCL) and vitelline duct length (VDL) using a VR system; and to correlate both measurements with the gestational age (GA) and crown-rump length (CRL) and the VDL with the yolk sac volume (YSV).

STUDY DESIGN

prospective cohort study. Serial three-dimensional (3D) ultrasound measurements were performed from six to 14weeks GA, resulting in 125 3D volumes. These volumes were analysed using an I-Space VR system.

SUBJECTS

Thirty-two healthy pregnant women with an ongoing, normal pregnancy.

OUTCOME MEASURES

the UCL, VDL, YSV and other related structures were measured.

RESULTS

The UCL, measurable in 55% of cases, was positively correlated to advancing GA and CRL (p<0.001). The VDL could be measured in 42% of cases and showed a positive relationship with GA and CRL (p<0.001). There was a significant (p<0.001) relationship between YSV and VDL.

CONCLUSIONS

the present study, facilitated by a VR system, is the first to provide an in-vivo longitudinal description of normal first trimester growth of the human umbilical cord and vitelline duct. Further studies will reveal whether these parameters can be used in detection of abnormal fetal development.

Placental aetiologies of foetal growth restriction: clinical and pathological differences

BACKGROUND

Placental morphology and pregnancy outcome differ between normal pregnancies and those with foetal growth restriction (FGR). Most reports do not differentiate among different placental injury patterns related to foetal growth restriction.

AIMS

To evaluate placental and perinatal findings in growth restricted pregnancies based on three placental injury patterns: maternal and foetal blood supply abnormalities, and villitis of unknown aetiology, compared to those of preeclampsia (PE) and normal pregnancies.

STUDY DESIGN

Retrospective review.

SUBJECTS

65 growth restricted newborns and their placentas.

OUTCOME MEASURES

Comparison of the clinical perinatal characteristics and outcomes, placental pathology and the number of syncytiocapillary membranes in the terminal villi, of the 65 FGR cases with 13 pregnancies complicated with preeclampsia (PE), and 25 uncomplicated pregnancies as controls, at 34-40weeks gestation.

RESULTS

The most common injury patterns of FGR placentas were maternal underperfusion (66%) (group 1), foetal blood supply abnormality (17%) (group 2), and villitis of unknown aetiology (17%) (group 3). The rate of induced labours was the highest in group 1 but the rate of operative deliveries due to suspected foetal asphyxia was the highest in group 2 (p<0.05). In the FGR cases, inverse relationship was found between birth weight and the number of syncytiocapillary membranes (r=-0.31, p<.05) in the maternal underperfusion FGR cases (group 1) only.

CONCLUSIONS

The different injury patterns in placentas of FGR patients may be correlated to different clinical outcomes. Placental examination in FGR pregnancies can provide a specific pathophysiologic explanation that may recur in subsequent pregnancies and lead to changes in follow-up and management.

Umbilical artery Doppler indices in small for gestational age fetuses: correlation with adverse outcomes and placental abnormalities

OBJECTIVE

The purpose of this study was to compare the screening efficiency of the umbilical artery systolic to diastolic ratio (S/D), pulsatility index (PI), and absent end-diastolic flow (AEDF) for adverse pregnancy outcomes and placental abnormalities in small for gestational age (SGA) fetuses.

METHODS

We conducted a retrospective cohort study of Doppler examinations of 161 nonanomalous SGA fetuses. The reliability of the S/D and PI were quantified by intraclass correlation coefficients. The association of the S/D, PI, and AEDF with adverse outcomes and placental abnormalities was compared by the chi(2) test.

RESULTS

There was a simple association of Doppler results with adverse outcomes, which was mitigated when controlled for gestational age. For all measures of adverse outcomes, the specificity of abnormal Doppler results exceeded the sensitivity, and the negative predictive value was greater than the positive predictive value. Comparing the S/D with the PI, there was no significant difference in the sensitivity; however, the specificity of the PI was at least 90% and exceeded that of the S/D for all outcomes. The intraclass correlation coefficients of the S/D and PI were similar, indicating no difference in reliability. Placental abnormalities were significantly more common in cases with abnormal Doppler values (positive predictive value, 94%) with no overlap in the types of placental lesions in most cases.

CONCLUSIONS

As an initial screen for adverse outcomes in SGA fetuses, the umbilical artery Doppler S/D, PI, and AEDF were imprecise. However, these measures were all strongly and similarly predictive of placental abnormalities, especially lesions of maternal underperfusion and fetal vascular obstruction.

Review: Diabetes and pregnancy: a review of pathology

Diabetes in pregnancy is associated with increased foetal morbidity and mortality. This article describes and reviews specific features of the placenta and the foetal anomalies seen in association with diabetes and briefly considers potential underlying mechanisms.

The association between intrauterine inflammation and spontaneous vaginal delivery at term: a cross-sectional study

Background

Different factors contribute to the onset of labor at term. In animal models onset of labor is characterized by an inflammatory response. The role of intrauterine inflammation, although implicated in preterm birth, is not yet established in human term labor. We hypothesized that intrauterine inflammation at term is associated with spontaneous onset of labor.

Methods/Results

In two large urban hospitals in the Netherlands, a cross-sectional study of spontaneous onset term vaginal deliveries and elective caesarean sections (CS), without signs of labor, was carried out. Placentas and amniotic fluid samples were collected during labor and/or at delivery. Histological signs of placenta inflammation were determined. Amniotic fluid proinflammatory cytokine concentrations were measured using ELISA. A total of 375 women were included. In term vaginal deliveries, more signs of intrauterine inflammation were found than in elective CS: the prevalence of chorioamnionitis was higher (18 vs 4%, p = 0.02) and amniotic fluid concentration of IL-6 was higher (3.1 vs 0.37 ng/mL, p<0.001). Similar results were obtained for IL-8 (10.93 vs 0.96 ng/mL, p<0.001) and percentage of detectable TNF-α (50 vs 4%, p<0.001).

Conclusions

This large cross-sectional study shows that spontaneous term delivery is characterized by histopathological signs of placenta inflammation and increased amniotic fluid proinflammatory cytokines.