Placenta and Umbilical Cord Abnormalities Seen With Stillbirth

Umbilical artery Thrombosis: A case report of prenatal diagnosis and systematic review of the literature

Umbilical Artery Thrombosis (UAT) is an extremely rare complication of pregnancy strongly associated with severe fetal distress and death. The pathogenesis is still unclear but it is often associated with anatomical cord abnormalities that leads to blood stasis and thrombosis formation. Other possible risk factors are maternal thrombophilia, autoimmune disease, gestational diabetes, hypertension disorders of pregnancy and Rh-alloimmunization. The most common clinical symptom is the reduction of fetal movements. The diagnosis is histopathological, but it can be suspected by clinical and prenatal ultrasound findings. Generally, the first choice therapy is the immediate delivery with cesarean section. This study reported a case of a spontaneous intrauterine UAT in a low-risk pregnancy and a systematic review of the literature on clinical, ultrasound and histopathological findings of UAT, in order to help clinicians in the diagnostic process and management of this rare complication.

Stillbirth and the placenta

Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been identified and include obstetrical complications, placental abnormalities, fetal malformations, infections, and medical complications in pregnancy. Placental abnormalities such as placental abruption, chorioangioma, vasa previa, and umbilical cord abnormalities have been identified as causes of death for a significant proportion of stillbirths. In the absence of placental abnormalities, the gross and histologic changes in the placenta in stillbirth are found when secondary to other etiologies. Here we describe both gross and histologic changes of the placenta that are associated with stillbirth.

Ultrasound blood flow characteristics changes in fetal umbilical artery thrombosis: A retrospective analysis

BACKGROUND

Umbilical artery thrombosis (UAT) is extremely uncommon and leads to adverse perinatal outcomes. Hypercoagulation of blood in pregnant women is suspected to be an important risk for UAT. Ultrasound is an effective way to detect thrombosis. The mother can monitor her own fetal health using ultrasound, which enables her to take preventative action in case of emergency.

AIM

To investigate ultrasonic blood signal after UAT in the umbilical artery, and evaluate the relationship between hypercoagulability and UAT.

METHODS

We described a case of a newly formed UAT with markedly altered ultrasonic indices of umbilical artery blood flow, and retrospectively studied it with 18 UAT patients confirmed by histopathology from October 2019 and March 2023 in Xiamen Women and Children's Hospital. Patients' information was collected from medical archives, including maternal clinical data, neonatal outcomes, pathological findings and ultrasonic indices of umbilical artery blood flow, such as systolic-diastolic duration ratio (S/D), resistance index (RI), pulsatility index (PI) and peak systolic velocity (PSV). Ultrasound and coagulation indices were analyzed with matched samples t-test and Wilcoxon rank sum test using the statistical packages in R (version 4.2.1) including car (version 3.1-0) and stats (version 4.2.1), and visualized by ggplot2 package (version 3.3.6).

RESULTS

A patient with normal findings in second and third-trimester routine ultrasound scan developed UAT with severe changes in ultrasonic indices of umbilical artery blood flow (within 2.5th of reference ranges) in a short period of time. Statistical analysis of umbilical artery blood flow ultrasound indices for 19 patients with UAT showed that the decrease in S/D, RI, and PI and increase of PSV during the disease process was greater than that of non-UAT. All 18 patients delivered in our hospital showed characteristic manifestations of UAT on histological examination after delivery, most of which (16/18) showed umbilical cord abnormalities, with 15 umbilical cord torsion and 1 pseudoknot. Coagulation parameters were not significantly changed in UAT patients compared with normal pregnancy women.

CONCLUSION

Significant changes in ultrasound indicators after UAT were demonstrated. PSV can play important roles in the diagnosis of UAT. Hypercoagulability alone is not sufficient for the occurrence of UAT.

Clinical significance of true umbilical cord knot: a propensity score matching study

OBJECTIVE

True umbilical cord knot (TUCK) is a rare finding that often leads to intensified surveillance and patient anxiety. This study sought to evaluate the incidence, risk factors, and obstetric and neonatal outcomes of TUCK.

METHODS

A retrospective cohort study was conducted at a tertiary university medical center in 2007-2019. Patients with singleton pregnancies diagnosed postnatally with TUCK were identified and compared to women without TUCK for obstetric and neonatal outcomes using propensity score matching (PSM).

RESULTS

TUCK was diagnosed in 780 of the 96,766 deliveries (0.8%). Women with TUCK were older than those without TUCK (32.57 vs. 31.06 years, P < 0.001) and had higher gravidity (3 vs. 2, P < 001) and a higher rate of prior stillbirth (1.76% vs. 0.43%, P < 0.01). Following covariate adjustment, 732 women with TUCK were compared to 7320 matched controls. TUCK was associated with emergency cesarean delivery due to non-reassuring fetal heart rate (2.54% vs. 4.35%, P = 0.008, OR 1.71, 95%CI 1.14-2.56) and intrapartum meconium-stained amniotic fluid (19.26% vs. 15.41%, P = 0.022, OR 1.31, 95%CI 1.04-1.65). Neonatal outcomes were comparable except for higher rates of 1-min Apgar score < 7 and neonatal seizures in the TUCK group. The stillbirth rate was higher in the TUCK group, but the difference was not statistically significant (1.23% vs 0.62%, P = 0.06, OR 1.96, 95%CI 0.96-4.03).

CONCLUSIONS

TUCK has several identifiable risk factors. Pregnant women with TUCK may cautiously be informed of the relatively low risks of major obstetric or perinatal complications. The lower occurrence of stillbirth in the TUCK group warrants further study.

The Placenta and Neonatal Encephalopathy with a Focus on Hypoxic-Ischemic Encephalopathy

Background: Placental examination is important for its diagnostic immediacy to correlate with maternal and/or fetal complications and parturitional difficulties. In a broader context, clinicopathologic studies of the placenta have addressed a range of pathogenetic questions that have led to conclusive and inconclusive results and interpretations. Methods: Recent standardized morphologic criteria and terminology of placental lesions have facilitated the ability to compare findings from studies that have focused on complications and outcomes of pregnancy. This review is an evaluation of recent studies on placental lesions associated with hypoxic-ischemic encephalopathy (HIE). Conclusion: No apparent consensus exists on whether it is fetal inflammation with the release of cytokines or chronic maternal and/or fetal vascular malperfusion is responsible for HIE with a lowering of the threshold for hypoxic ischemia. The counter argument is that HIE occurs solely as an intrapartum event. Additional investigation is necessary.

Cesarean section per se is not a risk factor for non-anatomical placenta creta

OBJECTIVE

To investigate whether mild forms of placenta creta (MPC) are more common in placentas delivered by cesarean section for non-anatomical indications than in placentas from vaginal deliveries.

METHODS

This is a retrospective clinical study in which MPC was diagnosed histologically by the presence of myometrial fibers in the decidua basalis or parietalis or in direct contact with the Rohr fibrinoid or chorionic villi. After excluding 111 cases at high risk for anatomical PC, placentas from 830 consecutive cesarean deliveries (group 1) were retrospectively statistically compared with 907 placentas from vaginal deliveries (group 2).

RESULTS

Statistically significant differences were found in six independent clinical and seven placental phenotypes. More frequently, pre-eclampsia, abnormal fetal heart rate tracing and umbilical artery Dopplers, hypercoiled umbilical cord, diffuse postuterine pattern of chronic hypoxic placental injury, and clusters of avascular or mineralized chorionic villi were found in group 1, while preterm delivery, induction of labor, and histological patterns related to stillbirth were observed in group 2.

CONCLUSION

MPC diagnosed in placentas from cesarean sections performed for non-anatomical indications is not statistically significantly more common than in those after vaginal delivery. Therefore, MPC may feature similar diagnostic correlations and portend a similar prognosis for future pregnancies.

Case report: Umbilical vessel aneurysm thrombosis and factor V Leiden mutation leading to fetal demise

Complicated pregnancies are nowadays a major public health concern, with possible lethality or sequelae both for the mother and the fetus. Blood coagulation disorders (including antiphospholipid syndrome, factor V Leiden mutation and antithrombin deficiency) and hypertensive gestational disorders are very well-known contributors of complicated pregnancies with poor fetal outcome, such as intrauterine growth retardation (IUGR) and fetal demise. Less commonly, vascular malformations of the placenta can also potentially lead to serious complications such as IUGR and fetal death. These malformations include hypercoiled umbilical cord, umbilical cord knot, umbilical cord varix, umbilical cord arterial or venous aneurysm, and velamentous insertion of the umbilical cord potentially leading to Benckiser's hemorrhage. Here, we report the case of a 29-year-old Gravida 2 Para 0 mother with previous history of stillbirth and smoking, admitted to the obstetrics department for the absence of fetal movement at 38 weeks of amenorrhea (WA). First-trimester and second-trimester routine ultrasounds were otherwise normal. Ultrasound performed at 38 WA revealed a 83 × 66 × 54 mm cystic heterogenous mass at the umbilical cord insertion. After delivery, fetal and placental pathology as well as maternal blood testing were performed. Fetal pathology was otherwise normal, except for diffuse congestion and meconial overload suggesting acute fetal distress. Fetal karyotype was normal (46 XX). Placental pathology revealed an umbilical artery aneurysm (UAA) at the base of the insertion of the umbilical cord, lined with a CD34⁺ CD31⁺ endothelium. After dissection, the aneurysm was filled with hemorrhagic debris, indicating aneurysm thrombosis. Histopathology revealed associated maternal vascular malperfusion (MVM) and increased peri-villous fibrin (IPF). Maternal blood tests revealed heterozygous factor V Leiden mutation, without other associated auto-immune conditions (such as antiphospholipid syndrome). Umbilical artery aneurysms remain extremely rare findings in the placenta, with <20 reported cases. Umbilical artery aneurysms have tendency to be located at the base of the insertion of the placenta, and lead to fetal demise in more than 60% of cases, mainly due to aneurysmal thrombosis, hematoma, possible vascular compression and/or rupture. Umbilical vessel aneurysms can be associated with trisomy 18 or 13. In our case, the association of factor V Leiden mutation, a hypercoagulable state, with UAA could explain massive thrombosis of the aneurysmal lumen and sudden fetal demise. Further consideration of current guidelines for surveillance and management of UAA would allow appropriate planned delivery in maternal care settings.

Imaging of placental circulations by 4D sonography with high-definition flow and spatiotemporal image correlation technology

Conventionally, two- and three- dimensional color Doppler ultrasonography are used to examine the placental vascularization, but there are limitations in the examinations. In this report, spatiotemporal image correlation (STIC) volume acquisition in high-definition flow, displayed in glass-body mode was used to study the placental vascularization in eight pregnancies. At 20 weeks' gestation, STIC technique allowed visualization of blood flow in the intraplacental branches of the umbilical artery (IPB) and the spiral artery jets in a cardiac cycle. In particular, blood flow from a mega jet penetrating more than half of the placental thickness was demonstrated. Small blood flow from a tertiary order branch of the IPB traversing the placenta and sharply diminishing into the uterine wall was also demonstrated. There were differences in the IPB pattern between normal pregnancies and pregnancies at risk of fetal growth restriction/pre-eclampsia. There were also differences in the appearance of IPB between 20- and 33-weeks' gestation. The results of this report support that it is feasible to use STIC technology to study the placental vascularization. This novel application of STIC technology can increase the understanding of the complex vascularization.

Adverse Perinatal Outcomes of True Knot of the Umbilical Cord: A Case Series and Review of Literature

A true knot of the umbilical cord (TKUC) is an actual knot formed in pregnancy. It is seen in approximately 0.3%-1.2% of all pregnancies. True knots are of significance as they can cause a wide spectrum of adverse perinatal outcomes like small for gestational age (SGA) fetus, low appearance, pulse, grimace, activity, and respiration (Apgar) score at birth, fetal hypoxia, and even fetal demise.

Here, we report a case series of three patients with TKUC and the varied adverse perinatal outcomes associated with them. A low-risk primigravida at term gestation had a suspicious non-stress test (NST). Repeat NST after maternal resuscitation became pathological. Emergency cesarean delivery was performed in view of pathological NST persisting despite intrauterine resuscitation. A healthy male baby weighing 2920 g was delivered, and the umbilical cord had a true knot.

A multigravida at 33 + 3 weeks of gestation was referred with fetal growth restriction (FGR). Color Doppler examination showed absent end-diastolic flow (AEDF) in the umbilical artery (UA). Cesarean delivery was performed in view of FGR stage two with AEDF in the UA at 34 weeks of gestation as per the Barcelona criteria. A male baby weighing 1505 g was delivered. The umbilical cord had a true tight knot. The baby had an Apgar score of 7 at one minute after birth but was shifted to the neonatal intensive care unit (NICU) in view of low birth weight and prematurity. The baby slowly gained weight and was discharged from NICU after 15 days in stable condition.

A multigravida at 32 weeks of gestation was referred with intrauterine fetal demise. Ultrasonography confirmed the presence of a single intrauterine dead fetus corresponding to 30 + 4 weeks of gestation with an estimated fetal weight (EFW) of 1633 g, amniotic fluid index (AFI) equal to nine, and presence of Spalding’s sign. Induction of labor was done, and she expelled a dead macerated male fetus weighing 1825 g. The infantogram was normal. A true umbilical cord knot was found.

The umbilical cord is the source of fetal blood supply; therefore, any cord abnormality can have a significant impact on the fetal outcome. There are various factors that can predispose to TKUC, such as polyhydramnios, increased cord length, monoamniotic twins, male baby, grand multiparity, small fetus, and amniocentesis. TKUC can lead to various adverse outcomes in pregnancy and labor like SGA fetus, low Apgar score at birth, fetal hypoxia, and fetal demise. TKUC increases the risk of fetal demise by as much as four times.

With the development of advanced techniques such as three-dimensional/four-dimensional color Doppler ultrasounds, TKUC can be diagnosed antenatally in the form of a four-leaf-clover, a “hanging-noose sign,” or by an unusual multicolor pattern in the cord. The prenatal detection rate of TKUC is only 12%. It mostly remains undetected unless visualized incidentally. Although TKUC is not rare and can have serious outcomes, the importance of its antenatal diagnosis has not been determined. It should be suspected in patients with risk factors, and emphasis should be placed on its antenatal diagnosis on ultrasonography to avoid obstetric disasters in otherwise low-risk females. Though there is no specific management of these cases, a good clinical outcome can be achieved if TKUC is diagnosed antenatally and monitored closely until fetal maturity is attained.

Clinically Relevant Prenatal Ultrasound Diagnosis of Umbilical Cord Pathology

Umbilical cord abnormalities are not rare, and are often associated with structural or chromosomal abnormalities, fetal intrauterine growth restriction, and poor pregnancy outcomes; the latter can be a result of prematurity, placentation deficiency or, implicitly, an increased index of cesarean delivery due to the presence of fetal distress, higher admission to neonatal intensive care, and increased prenatal mortality rates. Even if the incidence of velamentous insertion, vasa praevia and umbilical knots is low, these pathologies increase the fetal morbidity and mortality prenatally and intrapartum. There is a vast heterogeneity among societies’ guidelines regarding the umbilical cord examination. We consider the mandatory introduction of placental cord insertion examination in the first and second trimester to practice guidelines for fetal ultrasound scans. Moreover, during the mid-trimester scan, we recommend a transvaginal ultrasound and color Doppler assessment of the internal cervical os for low-lying placentas, marginal or velamentous cord insertion, and the evaluation of umbilical cord entanglement between the insertion sites whenever it is incidentally found. Based on the pathological description and the neonatal outcome reported for each entity, we conclude our descriptive review by establishing a new, clinically relevant classification of these umbilical cord anomalies.

Maternal and fetal vascular lesions of malperfusion in the placentas associated with fetal and neonatal death: results of a prospective observational study

BACKGROUND

Fetal death is one of the major adverse pregnancy outcomes and is common in low- and middle-income countries. Placental lesions may play an important role in the etiology of fetal and neonatal deaths. Previous research relating placental lesions to fetal death causation was hindered by a lack of agreement on a placental classification scheme. The Amsterdam consensus statement that was published in 2016 focused its attention on malperfusions in the maternal and fetal placental circulations.

OBJECTIVE

This study aimed to investigate the relationships of placental maternal and fetal vascular malperfusions in fetal and neonatal deaths, focusing on the most important maternal clinical conditions in the pathway to fetal and neonatal deaths, such as maternal hypertension, antepartum hemorrhage, and decreased fetal growth.

STUDY DESIGN

This was a prospective, observational cohort study conducted at 2 Asian sites. The data collected included clinical history, gross and histologic evaluations of the placenta, and several other investigations and were used to determine the cause of death. The placenta was evaluated at both sites using the Amsterdam consensus framework. We estimated the risk of placental maternal and fetal vascular malperfusions in fetal and neonatal deaths.

RESULTS

Between July 2018 and January 2020 in India and Pakistan, 1633 women with placentas available for the study provided consent. Of these women, 814 had fetal deaths, 618 had preterm live births and subsequent neonatal deaths, and 201 had term live births. The prevalence of maternal vascular malperfusion was higher in the placentas associated with fetal deaths (58.4%) and preterm neonatal deaths (31.1%) than in the placentas associated with term live births (15.4%). Adjusting for site, maternal vascular malperfusion had a relative risk of 3.88 (95% confidence interval, 2.70-5.59) in fetal deaths vs term live births and a relative risk of 2.07 (95% confidence interval, 1.41-3.02) in preterm neonatal deaths vs term live births. Infarcts and distal villous hypoplasia were the most common histologic components of maternal vascular malperfusion. Compared with maternal vascular malperfusion (58.4%), fetal vascular malperfusion was less common in the placentas associated with fetal deaths (19.0%). However, there were higher frequencies of fetal vascular malperfusion in the placentas associated with fetal deaths (19.0%) than in placentas associated with neonatal deaths (8.3%) or term live birth (5.0%). Adjusting for site, fetal vascular malperfusion had a relative risk of 4.09 (95% confidence interval, 2.15-7.75) in fetal deaths vs term live births and a relative risk of 1.77 (95% confidence interval, 0.90-3.49) in preterm neonatal deaths vs term live births. Furthermore, there was a higher incidence of maternal vascular malperfusion in cases of maternal hypertension (71.4%), small for gestational age (69.9%), and antepartum hemorrhage (59.1%) than in cases of fetal deaths with none of these conditions (43.3%). There was no significant difference in the occurrence of fetal vascular malperfusion in the 4 clinical categories.

CONCLUSION

Histologic examination of the placenta, especially for malperfusion disorders, is crucial in elucidating pathways to fetal and neonatal deaths in preterm infants. In particular, focusing on placental maternal and fetal vascular malperfusions during pregnancy is a means to identify fetuses at risk of fetal death and is an important strategy to reduce the risk of fetal death early delivery. We hope that the increased risk of fetal and neonatal deaths in these pregnancies can be reduced by the development of an intervention that reduces the likelihood of developing maternal and fetal vascular malperfusion.

Maternal obesity and stillbirth at term; placental pathology-A case control study

OBJECTIVE

The aim was to explore the potential role of the placenta for the risk of stillbirth at term in pregnancies of obese women.

METHODS

This was a case-control study comparing placental findings from term stillbirths with placental findings from live born infants. Cases were singleton term stillbirths to normal weight or obese women, identified in the Stockholm stillbirth database, n = 264 and n = 87, respectively. Controls were term singletons born alive to normal weight or obese women, delivered between 2002-2005 and between 2018-2019. Placentas were compared between women with stillborn and live-born infants, using logistic regression analyses.

RESULTS

A long and hyper coiled cord, cord thrombosis and velamentous cord insertion were stronger risk factors for stillbirth in obese women compared to normal weight women. When these variables were adjusted for in the logistic regression analysis, also adjusted for potential confounders, the odds ratio for stillbirth in obese women decreased from 1.89 (CI 1.24-2.89) to 1.63 (CI 1.04-2.56).

CONCLUSION

Approximately one fourth of the effect of obesity on the risk of stillbirth in term pregnancies is explained by umbilical cord associated pathology.

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.

Silver nanoparticles in the fetal brain: new perspectives in understanding the pathogenesis of unexplained stillbirths

We report, for the first time, the surprising presence of toxic nanoparticles, especially silver, in the brain of a fetus, who died unexpectedly at the end of a regular pregnancy. After an accurate autopsy, including the examination of the fetal annexes, an in-depth anatomopathological study of the nervous system and a search by scanning electron microscopy of nanoparticles in the brain, we highlighted the sequence of events that may have led to this fetal death, triggered primarily by the transition of nanosized xenobiotics from the mother to the fetal bloodstream. From this report emerges the importance of considering the search of nanosubstances in the brain during routine investigations following unexpected and unexplained fetal and infant deaths.

Temporal heterogeneity of placental segmental fetal vascular malperfusion: timing but not etiopathogenesis

Clinicopathologic correlations of segmental villous avascularity and other histological lesions of segmental fetal vascular malperfusion (SFVM) were analyzed retrospectively to determine whether lesions of various durations reflect different etiopathogeneses. The frequencies of 25 independent clinical and 43 placental phenotypes were statistically compared by ANOVA or Chi-square among 3 groups containing a total of 378 placentas with SFVM: group 1 contained 44 cases of recent SFVM (endothelial fragmentation, villous hypovascularity by CD34 immunostain, and/or stromal vascular karyorrhexis); group 2 contained 264 cases of established SFVM (clusters of avascular villi); and group 3 contained 70 cases of remote SFVM (villous mineralization). Statistically significant differences among the three study groups (p Bonferroni < 0.002) were found in four clinical variables (gestational age, frequencies of macerated stillbirth, induction of labor, and cesarean section) and in five placental variables (frequencies of fetal vascular ectasia, stem vessel luminal vascular abnormalities, diffusely increased extracellular matrix in chorionic villi, chorionic disk extravillous trophoblast microcysts, and excessive extravillous trophoblasts in the chorionic disc). In summary, the absence of statistically significant differences between the study groups regarding the most common causes of SFVM (hypertensive conditions of pregnancy, diabetes mellitus, fetal anomalies, and clinical and pathological features of umbilical cord compromise) is evidence that the three types of SFVM reflect temporal heterogeneity rather than etiopathogenesis. This evidence can be used to date the onset of fetal vascular malperfusion before delivery or stillbirth. The coexistence of different SVFM lesions of various durations indicates ongoing or repeat occurrences of FVM rather than single episodes.

Hypertension during pregnancy and risk of stillbirth: challenges in a developing country

Objective: To explore the factors associated with hypertensive disorders of pregnancy (HDP) in women experiencing stillbirth (SB).Material and methods: It was an observational, analytical case-control study, done as part of the World Health Organization South-East Asian Region Office SB project. The epidemiological profile, history, clinical features, and investigations of stillborn cases having HDP were noted, an equal number of age and parity matched subjects with HDP having livebirth were taken as controls.Results: Out of 46,816 deliveries, 1239 (26.2/1000) were stillborn. The maternal causes contributed 374/1239 (30.2%) stillbirths according to the CODAC classification, HDP was the most common maternal cause (304/1239, 24.9%). Subjects with HDP were included as cases. On comparing the cases with controls it was found that significantly more number of cases had inadequate antenatal visits (p < .001, OR -4.8), two or more abortions (p < .001, OR -1.9), early onset of hypertension (p < .0001, OR -5.6) and complications such as fetal growth restriction (FGR) (p < .001, OR -2.3) and abruption (p < .001, OR -4.0). Women with preeclampsia were less likely to have SB compared to those with gestational or chronic hypertension (p = .0001, OR -2.3). The birth weight/placental weight ratio of more than eight had the highest odds ratio regarding contribution to SB among hypertensive women (p = .0001 OR -6.7).Conclusion: In women with HDP, adequate antenatal care would lead to the prevention of complications such as anemia, abruption, and FGR, and thus prevent SB. The high BW/PW ratio is a potential marker of risk of SB.

Segmental villous mineralization: A placental feature of fetal vascular malperfusion

INTRODUCTION

This retrospective analysis was performed to find out if clusters of mineralized chorionic villi can be regarded as an independent feature of fetal vascular malperfusion (FVM).

METHODS

Of all 1698 placentas reviewed by the author during the last 10 years, 39 (2.3%) showed clusters of mineralized chorionic villi (Group 1), 100 cases (5.9%) showed randomly scattered mineralized chorionic villi with without clustering (Group 2), and the remaining 1559 placentas showed no villous mineralization (comparative Group 3). In doubtful cases, histochemistry stains were performed to determine the pattern of villous mineralization. Twenty three independent clinical and 43 placental variables were statistically compared among the groups: descriptive statistics (Chi-square, Fisher test or signed rank test), and logistics regression model.

RESULTS

Clinically, Group 1 featured shorter gestational age than Group 2, and in addition to shorter gestational age, more common oligohydramnios, polyhydramnios, induction of labor, macerated stillbirth and fetal growth restriction than Group 3. Of placental variables, fetal vascular ectasia, and clusters of avascular chorionic villi were more common in Group 1 than in Group 2, and in addition, segmental villous stromal vascular karyorrhexis was more common than in Group 3. By the logistics regression mode, segmental villous mineralization was independently associated with other histological features of FVM as a group and particularly with clusters of sclerotic chorionic villi.

DISCUSSION

FVM is characterized by temporal heterogeneity, i.e. coexistence of lesions of various duration, and strongly and independently correlates with clusters of mineralized chorionic villi. Therefore, segmental villous mineralization should be included into the category of segmental FVM. It can be seen even in totally fibrotic placentas of prolonged stillbirth when other histological features of segmental vascular malperfusion can be obscured by global villous sclerosis.

CD34 immunostain increases the sensitivity of placental diagnosis of fetal vascular malperfusion in stillbirth

INTRODUCTION

Postmortem regressive placental changes of stillbirth may obscure the pre-existing placental histomorphology. The objective is to find out whether the use of CD34 immunostain can increase the sensitivity of placental examination in the diagnosis of fetal vascular malperfusion (FVM).

METHODS

Twenty six independent clinical and 46 placental variables of 46 placentas from stillbirths were statistically compared to those of 92 placentas from livebirths. One histologically most unremarkable section per case was stained using double E-cadherin/CD34 immunostain (ECCD34). Clusters of avascular/hypovascular chorionic villi on hematoxylin and eosin (H&E) staining system and/or CD34 immunostaining, the latter also including endothelial CD34 positive debris in the villous stroma, were regarded as evidence of FVM.

RESULTS

The gestational age and cesarean section rate were statistically significantly lower and the induction of labor and mild erythroblastosis of fetal blood was higher, but the frequencies of clinical and placental features of umbilical cord compromise were not statistically significant between stillbirths and livebirths, respectively. By using H&E stain, 9 (19.6%) of stillbirths and 30 (32.6%) of livebirths showed clusters of avascular villi on H&E. By CD34, the rates of FVM increased to 23 (50%) and 34 (40%), respectively. The increase was statistically significant for stillbirths only (Chi square = 9.4, p = 0.002). By CD34, new clusters of hypovascular chorionic villi or villi with endothelial fragmentation were found in 23 stillbirth cases (50%) as opposed to livebirths (29 cases, 31.5%)(Chi square = 9.4, p = 0.002).

DISCUSSION

When compared with H&E stain, the CD34 increases sensitivity and/or upgrades FVM in placental examination in stillbirths but not in livebirths.

Anatomical Pathology of the Umbilical Cord and Its Maternal and Fetal Clinical Associations in 434 Newborns

Introduction Umbilical cord (UC) abnormalities and their clinical relations in 434 newborns were analyzed. We had previously reported on clinical associations of long and short UCs with any kind of malformation. This study focuses on other UC features (insertion, vessels, entanglements, coiling, and knots) and their associations with clinical characteristics and neonatal prognosis. Methods An observational analytic study was performed on placentas from consecutive deliveries. Ordered logistic regression with bivariate and multivariate analysis was performed to evaluate the relationship between variables of interest concerning UC abnormalities. Results A total of 434 placentas made up the study. UC abnormalities were abnormal insertion, 82 (18.86%); coiling (hypo and hypercoiled), 177 (40.78%); single umbilical artery (SUA), 4 (0.92%); entanglements, 8 (1.84%); true knots, 3 (0.69%); webs in UC base, 9 (2.07%); and right twist, 68 (15.67%). After analyzing maternal and fetal complications during pregnancy, multivariate analysis confirmed the recognized association between malformations and SUA and male gender; further confirmation was also made between hypertensive disorders of pregnancy and true knots. Discussion UC abnormalities associated with undesirable outcomes are varied and should be recognized and described. Clinical factors associated with anatomical UC abnormalities are not completely understood and justify forthcoming studies.

Perinatal mortality classification: an analysis of 112 cases of stillbirth

This was a retrospective cohort analysis of stillbirths that occurred from January 2004 to December 2013 in our institution. We compared Tulip and Wigglesworth classification systems on a cohort of stillbirths and analysed the main differences between these two classifications. In this period, there were 112 stillbirths of a total of 31,758 births (stillbirth rate of 3.5 per 1000 births). There were 99 antepartum deaths and 13 intrapartum deaths. Foetal autopsy was performed in 99 cases and placental histopathological examination in all of the cases. The Wigglesworth found 'unknown' causes in 47 cases and the Tulip classification allocated 33 of these. Fourteen cases remained in the group of 'unknown' causes. Therefore, the Wigglesworth classification of stillbirths results in a higher proportion of unexplained stillbirths. We suggest that the traditional Wigglesworth classification should be substituted by a classification that manages the available information.

Stillbirth: Correlations Between Brain Injury and Placental Pathology

Chronic placental pathologic processes such as fetal thrombotic vasculopathy have been linked to brain injury in neonates. We hypothesize that using stillbirth as a model, placental pathology can predict risk for hypoxic-ischemic brain injury. From a single institutional database of stillbirths ≥23 weeks' gestational age, we included cases with full autopsy and neuropathology examination. Bivariable analyses were performed to identify whether there was an association between placental pathologic findings and neuropathologic findings. Logistic regression was used to control for potential confounders. Among 97 potential cases, adequate tissue was analyzable from 79 cases (mean gestational age  =  33 weeks). Acute central nervous system hemorrhage and acute neuronal necrosis were the most common neuropathologic processes seen in this cohort (57% for each). Maternal vascular underperfusion was the most common placental pathology but was not significantly associated with a specific neuropathologic finding. High-grade chronic villitis (HGCV) and fetal thrombotic vasculopathy (FTV) were significantly associated with increased risk for pontosubicular necrosis (odds ratios, 15.73 and 3.79, respectively). These associations persisted after controlling for potential confounders. Chronic placental pathologies, specifically HGCV and FTV, were associated with pontosubicular necrosis, suggesting that placental pathology involving the fetal vasculature and altered fetoplacental blood flow carry the greatest likelihood of hypoxic/ischemic brain injury.

Velamentous cord insertion as a risk factor for obstetric outcome: a retrospective case-control study

PURPOSE

Velamentous umbilical cord insertion (VCI) is associated with adverse pregnancy outcomes. Literature lacks data on Doppler. We aimed to evaluate obstetric outcomes and results of uterine and umbilical artery Doppler flowmetry associated with VCI.

MATERIALS AND METHODS

In a retrospective case-control study, 108 singleton pregnancies with VCI were age- and body mass index-matched to 108 singleton pregnancies without VCI. The main outcome parameters were obstetric outcome, pregnancy-related complications, uterine artery flowmetry at the second-trimester screening, and umbilical artery flowmetry before delivery. Statistical analysis was accomplished using Pearson's Chi-square test or Fisher's exact test, and the Mann-Whitney U test, where appropriate.

RESULTS

Pregnancies with VCI revealed a significantly higher PI in the umbilical artery during the last measurement before delivery (1.00 ± 0.25 vs. 0.90 ± 0.10; p = 0.001). Gestational age at this measurement did not differ between the groups. Fetal malformations and intrauterine fetal death were more common in pregnancies with VCI (12.7 vs. 0 %; p < 0.001, and 6.5 vs. 0 %; p = 0.014, respectively). Patients with VCI delivered significantly earlier (36.2 ± 4.5 vs. 38.4 ± 2.6; p < 0.001).

CONCLUSION

Higher rates of (early) preterm delivery were found in pregnancies with VCI. Fetuses with VCI also suffered from malformations and IUFD more frequently. The last pulsatility index value in the umbilical artery, before delivery, was significantly higher in pregnancies with VCI, which is of uncertain clinical value.

The role of preterm placental calcification on assessing risks of stillbirth

INTRODUCTION

Stillbirth is an important issue in antenatal care and much remains unknown. This cohort study aims to explore the previously un-identified risk factor of third-trimester stillbirth to determine if Grade III preterm placental calcification (PPC) is associated with stillbirth.

METHODS

At a tertiary teaching hospital, obstetric ultrasonography was performed at 28 weeks' gestation to establish a diagnosis of PPC. Pregnancies with multifetal gestations, major fetal congenital anomalies, termination, cord accidents, apparent intrauterine infection, and antepartum complications were excluded.

RESULTS

15,122 eligible pregnancies were categorized as stillbirth (n = 99) and livebirth (n = 15,023) groups. Between these two groups, there were no significant differences in maternal age, BMI, and parity, but significant differences in smoking and in PPC (35.4% vs 6.3%, p < 0.001) were observed. The peak occurrence of stillbirths was at 30 and 37 weeks' gestation, with a bimodal distribution of 11 and 17 stillbirths, respectively. For pregnancies with or without PPC, the incidences of stillbirths per-1000-births were 35.9 and 4.5, respectively. Using Kaplan-Meier survival analysis, at 40 weeks' gestation the cumulative stillbirth risk for pregnancies with PPC was higher compared to those without PPC. Logistic regression revealed that after adjusting for the effects of smoking and demographic factors, the risk of stillbirth (adjusted OR:7.62; 95% CI:5.00-11.62) was much higher when PPC was present.

DISCUSSION

Grade III PPC is associated with a higher incidence of stillbirth, and identified an independent risk factor. Being a pathologic implication, it may precede this negative outcome and can serve as a warning sign or marker when noted on ultrasonography.

Fetal growth restriction and risk of cerebral palsy in singletons born after at least 35 weeks' gestation

OBJECTIVE

The objective of the study was to improve the understanding of etiological paths to cerebral palsy (CP) that include fetal growth restriction by examining factors associated with growth restriction that modify CP risk.

STUDY DESIGN

In a total population of singletons born at or after 35 weeks, there were 493 children with CP and 508 matched controls for whom appropriateness of fetal growth could be estimated. Fetal growth was considered markedly restricted if birthweight was more than 2 SD below optimal for gender, gestation, maternal height, and parity. We examined maternal blood pressure in pregnancy, smoking, birth asphyxia, and major birth defects recognized by age 6 years as potential modifiers of CP risk in growth-restricted births.

RESULTS

More than 80% of term and late preterm markedly growth-restricted singletons were born following a normotensive pregnancy and were at statistically significantly increased risk of CP (odds ratio, 4.81; 95% confidence interval, 2.7-8.5), whereas growth-restricted births following a hypertensive pregnancy were not. Neither a clinical diagnosis of birth asphyxia nor potentially asphyxiating birth events occurred more frequently among growth-restricted than among appropriately grown infants with CP. Major birth defects, particularly cerebral defects, occurred in an increasing proportion of CP with increasing growth deficit. The factor most predictive of CP in growth-restricted singletons was a major birth defect, present in 53% of markedly growth-restricted neonates with later CP. Defects observed in CP were similar whether growth restricted or not, except for an excess of isolated congenital microcephaly in those born growth restricted. The highest observed CP risk was in infants with both growth restriction and a major birth defect (8.9% of total CP in this gestational age group, 0.4% of controls: odds ratio, 30.9; 95% confidence interval, 7.0-136).

CONCLUSION

The risk of CP was increased in antenatally growth-restricted singletons born at or near term to normotensive mothers. In growth-restricted singletons, a major birth defect was the dominant predictor, associated with a 30-fold increase in odds of CP. Identification of birth defects in the growth-restricted fetus or neonate may provide significant prognostic information.

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.

Angiogenesis in the placenta: the role of reactive oxygen species signaling

Proper placental development and function are central to the health of both the mother and the fetus during pregnancy. A critical component of healthy placental function is the proper development of its vascular network. Poor vascularization of the placenta can lead to fetal growth restriction, preeclampsia, and in some cases fetal death. Therefore, understanding the mechanisms by which uterine stressors influence the development of the placental vasculature and contribute to placental dysfunction is of central importance to ensuring a healthy pregnancy. In this review we discuss how oxidative stress observed in maternal smoking, maternal obesity, and preeclampsia has been associated with aberrant angiogenesis and placental dysfunction resulting in adverse pregnancy outcomes. We also highlight that oxidative stress can influence the expression of a number of transcription factors important in mediating angiogenesis. Therefore, understanding how oxidative stress affects redox-sensitive transcription factors within the placenta may elucidate potential therapeutic targets for correcting abnormal placental angiogenesis and function.

Pathology of the stillborn infant for the general pathologist: part 1

As the information obtained from previable fetal and stillbirth autopsies is used not only to explain the loss to the parents, but for future pregnancy planning, general pathologists need to be comfortable in dealing with these autopsies. The importance of an adequate fetal examination has been emphasized in a recent policy on the subject by the American Board of Pathology http://www.abpath.org/FetalAutopsyPolicy.pdf. This review paper covers the approach to the fetal and stillbirth autopsy. This first article covers the approach to the nonanomalous and anomalous autopsy. Hydrops fetalis will be covered in the second part of this series to be published subsequently.

A holistic antenatal model based on yoga, Ayurveda, and Vedic guidelines

The prevalence of pregnancy complications are on the rise globally with severe consequences. According to the World Health Organization (WHO, 2009), every minute, at least one woman dies and 20 are affected by the complications related to pregnancy or childbirth. While the root cause of pregnancy complications is unclear, it likely has physical, psychological, social, and spiritual aspects. The Vedas are a rich source of antenatal health care guidelines in all these aspects. The primary objective of the authors was to compile the scriptural and scientific evidence for a holistic antenatal model of yoga with emphasis on sociocultural Indian practices.

Influence of the umbilical cord insertion site on the optimal individual birth weight achievement

Study Question. To determine whether the umbilical cord insertion site of singleton pregnancies could be linked to the newborn birth weight at term and its individual growth potential achievement. Material and Methods. A cohort study including 528 records of term neonates was performed. Each neonate was assessed for growth adjusted for gestational age according to the infant's growth potential using the AUDIPOG module. We considered two categories of umbilical cord insertions: central and peripheral. Intrauterine growth restriction was defined as birth weight below the 10th percentile. Statistical analysis was performed using Chi-square, Student's t test, Wilcoxon test, ANOVA, and logistic regression. Results. We observed a total of 343 centrally inserted cords versus 185 peripheral cords. There were twice as many smokers in the mothers of the peripheral category compared to the centrally inserted ones. More importantly, we demonstrated that only 17/343 (5.0%) of infants with central cord insertion were growth restricted, compared to 37/185 (20.0%) of the infants born with a peripheral insertion. Neonates with centrally inserted cord were significantly heavier. Conclusion. The umbilical cord insertion site of singleton pregnancies is associated with the newborn's birth weight at term and its individual growth potential achievement.

Peripheral insertion of umbilical cord

Numerous studies have addressed the significance of marginal and membranous umbilical cord (UC) insertion. Recent reports suggest that an eccentrically inserted UC may also be important. This case-control study assessed the potential relevance of peripheral insertion of UC (PIUC), defined as <3 cm from the nearest margin. Singleton placentas (n  =  1418) submitted to the pathology department over an 18-month period were analyzed. Each case of PIUC (n  =  119) was matched with a control placenta of the same gestational age. Placentas with marginal or membranous UC and multiple gestations were excluded. The overall prevalence of PIUC was 8.4%, but PIUC frequency was significantly increased in premature births at <28 weeks (21.4%, P < 0.001). There was no association with other adverse pregnancy outcomes. PIUC was associated with decreased placental weight Z-score (-0.69 ± 0.92 versus -0.22 ± 1.3, P  =  0.0056), but not fetal weight Z-score, suggesting increased utilization of placental reserve. PIUC was also associated with relatively elongated placentas (length minus width: 2.6 ± 3.2 versus 1.0 ± 3.1, P  =  0.006). PIUC tended to be more frequent in young primiparous mothers and was significantly less common in women with a history of prior curettage (66% vs 50%, P  =  0.013). These data, together with equivalent rates of prior cesarean section, multiparity, and advanced maternal age, support a primary developmental disorder as opposed to secondary placental migration due to underlying uterine abnormalities ("trophotropism"). Except for a borderline significant association with findings suggestive of maternal malperfusion (P  =  0.078), PIUC was not associated with other placental lesions.

Intrauterine growth restriction: screening, diagnosis, and management

BACKGROUND

Intrauterine growth restriction (IUGR) is an obstetrical complication, which by definition would screen in 10% of fetuses in the general population. The challenge is to identify the subset of pregnancies affected with pathological growth restriction in order to allow intervention that would decrease morbidity and mortality.

OBJECTIVE

The purpose of this guideline is to provide summary statements and recommendations and to establish a framework for screening, diagnosis, and management of pregnancies affected with IUGR.

METHODS

Affected pregnancies are compared with pregnancies in which the fetus is at an appropriate weight for its gestational age. History, physical examination, and laboratory investigations including biochemical markers and ultrasound characteristics of IUGR are reviewed, and a management strategy is suggested.

EVIDENCE

Published literature in English was retrieved through searches of PubMed or MEDLINE, CINAHL, and The Cochrane Library in January 2013 using appropriate controlled vocabulary via MeSH terms (fetal growth restriction and small for gestational age) and key words (fetal growth, restriction, growth retardation, IUGR, low birth weight, small for gestational age). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table).

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in this guideline should increase clinician recognition of IUGR and guide intervention where appropriate. Optimal long-term follow-up of neonates diagnosed as IUGR may improve their long-term health.

Perinatal pathology: practice suggestions for limited-resource settings

The practice of perinatal pathology in much of the world suffers, as do all subspecialties of anatomic pathology, from inadequate resources (equipment, consumables, and both professional and technical personnel), from lack of education (not only of the pathologist but also of the clinicians responsible for sending the specimens, and the technicians processing the specimens), and from lack of appropriate government sector support. Perinatal pathology has significant public health-related utility and should be championing its service by providing maternal and fetal/infant mortality and morbidity data to governmental health ministries. It is with this pathologic data that informed decisions can be made on health-related courses of action and allocation of resources. These perinatal pathology data are needed to develop appropriate public health initiatives, specifically toward achieving the Millennium Developmental Goals as the best way to effectively decrease infant and maternal deaths and to determine causes of perinatal mortality and morbidity. The following overview will focus on the utility of perinatal pathology specifically as related to its public health function and will suggest methods to improve its service in resource-poor settings. This article is offered not as a critique of the current practice that most pathologists find themselves working in globally, but to provide suggestions for improving perinatal pathology services, which could be implemented with the limited available resources and manpower most pathology departments currently have. In addition, we offer suggestions for graded improvements ("ramping up") over time.

Classification of stillbirths and risk factors by cause of death--a case-control study

OBJECTIVE

To investigate risk factors for stillbirths by cause, using the Causes of Death and Associated Conditions (CODAC) classification system for perinatal deaths.

DESIGN

Case-control study.

SETTING

Two university hospitals in Oslo, Norway, January 1990 through December 2003.

SAMPLE

Women with stillbirth after 22 gestational weeks (n = 377) and controls with live births (n = 1 215), and a subsample of 105 cases and 262 controls.

METHODS

Socio-demographic, clinical and thrombophilic risk factors for stillbirths were assessed by cause of death in univariate and multivariable logistic regression analyses. Stillbirths were classified according to CODAC based on information from medical records and validated placenta histology.

MAIN OUTCOME MEASURES

Causes of stillbirths in percentages, prevalence, odds ratios and adjusted odds ratios for potential risk factors.

RESULTS

Approximately half of the women (n = 190) had placental and 19.4% (n = 73) unknown cause of stillbirth. Placental-associated conditions were registered in 18% (n = 68) of cases with a non-placental or an unknown cause. Smoking and small-for-gestational age were more prevalent in all causal groups, compared with controls, whereas twin pregnancy, hypertension and diabetes were more prevalent only among women with placental and unknown causes of stillbirth. The F2rs179963 polymorphism and combined thrombophilia were significant risk factors for stillbirth with placental causes and antiphospholipid antibodies for stillbirth with non-placental causes.

CONCLUSIONS

Two-thirds of all stillbirths (68%) were caused by or associated with placental pathology. Risk factors differed somewhat according to cause, apart from smoking and small-for-gestational age, which were significant risk factors across the causal groups.

Velamentous cord insertion in a singleton pregnancy: an obscure cause of emergency cesarean-a case report

Approximately 2% of low-risk pregnant women still require an emergency Cesarean section after the onset of labor. Because it is likely that half of these cases are associated with placental and umbilical cord abnormalities, it is thought that prenatal detection of such abnormalities would reduce the number of emergency cesarean sections in low-risk women. Velamentous cord insertion is an abnormal cord insertion in which the umbilical vessels diverge as they traverse between the amnion and chorion before reaching the placenta. With a reported incidence of 1% in singleton pregnancies, it has been associated with several obstetric complications. This condition has been diagnosed by ultrasonography with a sensitivity of 67% and specificity of 100% in the second trimester. The present case highlights the importance of the systematic assessment of the placental cord insertion site at routine obstetric ultrasound and the potential of identifying pregnancies with velamentous insertion and, therefore, those at risk for obstetric complications.

Placental histologic criteria for diagnosis of cord accident: sensitivity and specificity

"Cord accident" (compromised umbilical blood flow) as a cause of stillbirth is underreported, mainly due to a lack of diagnostic criteria. Based on fetal vascular pathology in the placenta, we have previously established histologic criteria for the diagnosis of cord accident. In the current study, we set out to test the sensitivity and specificity of these criteria by reviewing an independent set of stillbirth cases. Placental slides from 26 cases (in which cord accident was deemed the cause of death) and 62 controls (in which the cause of death was anything other than cord accident) were reviewed. The following histologic changes were noted: (1) dilated fetal vessels, (2) thrombosis in fetal vessels, and (3) avascular or near-avascular chorionic villi. "Minimal" criteria were defined as the presence of dilated and thrombosed fetal vessels, while the additional presence of focal or regional avascular or near-avascular villi satisfied the complete criteria. Of the 62 stillbirth controls with cause of death other than cord accident, 13 (21%) met the minimal criteria (specificity 79%) and only 4 (6%) met the complete criteria for cord accident (specificity 94%). In contrast, of the 26 cases with a cause of death related to cord accident, 16 met the minimal criteria (sensitivity 62%) and 12 met the complete criteria (sensitivity 46%). These histologic criteria identify cases of cord accident as a cause of stillbirth with very high specificity. This study confirms the utility of these criteria for diagnosis of cord accident and further stresses placental examination in evaluation of stillbirths.

High prevalence of hypertension and placental insufficiency, but no in utero HIV transmission, among women on HAART with stillbirths in Botswana

Background

Increased stillbirth rates occur among HIV-infected women, but no studies have evaluated the pathological basis for this increase, or whether highly active antiretroviral therapy (HAART) influences the etiology of stillbirths. It is also unknown whether HIV infection of the fetus is associated with stillbirth.

Methods

HIV-infected women and a comparator group of HIV-uninfected women who delivered stillbirths were enrolled at the largest referral hospital in Botswana between January and November 2010. Obstetrical records, including antiretroviral use in pregnancy, were extracted at enrollment. Verbal autopsies; maternal HIV, CD4 and HIV RNA testing; stillbirth HIV PCR testing; and placental pathology (blinded to HIV and treatment status) were performed.

Results

Ninety-nine stillbirths were evaluated, including 62 from HIV-infected women (34% on HAART from conception, 8% on HAART started in pregnancy, 23% on zidovudine started in pregnancy, and 35% on no antiretrovirals) and 37 from a comparator group of HIV-uninfected women. Only 2 (3.7%) of 53 tested stillbirths from HIV-infected women were HIV PCR positive, and both were born to women not receiving HAART. Placental insufficiency associated with hypertension accounted for most stillbirths. Placental findings consistent with chronic hypertension were common among HIV-infected women who received HAART and among HIV-uninfected women (65% vs. 54%, p = 0.37), but less common among HIV-infected women not receiving HAART (28%, p = 0.003 vs. women on HAART).

Conclusions

In utero HIV infection was rarely associated with stillbirths, and did not occur among women receiving HAART. Hypertension and placental insufficiency were associated with most stillbirths in this tertiary care setting.

The preterm birth syndrome: issues to consider in creating a classification system

A comprehensive classification system for preterm birth requires expanded gestational boundaries that recognize the early origins of preterm parturition and emphasize fetal maturity over fetal age. Exclusion of stillbirths, pregnancy terminations, and multifetal gestations prevents comprehensive consideration of the potential causes and presentations of preterm birth. Any step in parturition (cervical softening and ripening, decidual-membrane activation, and/or myometrial contractions) may initiate preterm parturition, and should be recorded for every preterm birth, as should the condition of the mother, fetus, newborn, and placenta, before a phenotype is assigned.

Stillbirths: the way forward in high-income countries

Stillbirth rates in high-income countries declined dramatically from about 1940, but this decline has slowed or stalled over recent times. The present variation in stillbirth rates across and within high-income countries indicates that further reduction in stillbirth is possible. Large disparities (linked to disadvantage such as poverty) in stillbirth rates need to be addressed by providing more educational opportunities and improving living conditions for women. Placental pathologies and infection associated with preterm birth are linked to a substantial proportion of stillbirths. The proportion of unexplained stillbirths associated with under investigation continues to impede efforts in stillbirth prevention. Overweight, obesity, and smoking are important modifiable risk factors for stillbirth, and advanced maternal age is also an increasingly prevalent risk factor. Intensified efforts are needed to ameliorate the effects of these factors on stillbirth rates. Culturally appropriate preconception care and quality antenatal care that is accessible to all women has the potential to reduce stillbirth rates in high-income countries. Implementation of national perinatal mortality audit programmes aimed at improving the quality of care could substantially reduce stillbirths. Better data on numbers and causes of stillbirth are needed, and international consensus on definition and classification related to stillbirth is a priority. All parents should be offered a thorough investigation including a high-quality autopsy and placental histopathology. Parent organisations are powerful change agents and could have an important role in raising awareness to prevent stillbirth. Future research must focus on screening and interventions to reduce antepartum stillbirth as a result of placental dysfunction. Identification of ways to reduce maternal overweight and obesity is a high priority for high-income countries.