Abnormal Cord Insertion Research Articles

Placental pathology in twin to twin transfusion syndrome twins after fetoscopic laser photocoagulation

Placental pathology in twin to twin transfusion syndrome twins after fetoscopic laser photocoagulation

Prevalence of velamentous and marginal umbilical cord insertions; a comparison of term singleton ART and non-ART pregnancies

Abnormal umbilical cord insertion (i.e., velamentous or marginal insertion) sometimes results in serious obstetric complications. The reported adverse outcomes include placenta previa, fetal growth restriction, non-reassuring fetal status requiring an emergency Cesarean section, and fetal exsanguination due to the rupture of vasa previa. This study was conducted to investigate whether pregnancies obtained by assisted reproductive technologies (ART) influence the prevalence of anomalous cord insertions. Observational study and comparative analysis. We reviewed the records of 6604 consecutive singleton, term labor and delivery cases in our clinic between the study period of January 2010 to April 2014, including personal details, obstetric history, details of infertility treatment, and insertion site of the umbilical cord. They were categorized according to their conception method (Group A: ART pregnancies, n=253, Group B: non-ART pregnancies, n=6351). Abnormal cord insertion was divided into two categories: velamentous insertion(VI) and marginal insertion(MI). Odds ratio, 95% confidence intervals(CI), and significance of the odds ratio were calculated for the conditions of interest. As for maternal age and their parity both in Group A and Group B, there were no statistically significant differences between the presence and the absence of abnormal cord insertion. The prevalence of abnormal cord insertion was 19.3% (VI: 4.3%, MI: 15.0%) in Group A, and 6.4% (VI: 0.6%, MI: 5.8%) in Group B. The odds ratio for delivery with VI in Group A as opposed to Group B was calculated as 7.6 (95% CI: 3.8 - 15.0), P<0.001 (X2=46.4, 1 df). The odds ratio for delivery with MI in Group A as opposed to Group B was 2.9 (95% CI: 2.0 - 4.1), P<0.001 (X2=35.7, 1 df). Tabled 1Prevalence of Abnormal Cord InsertionsGroup A (ART: n=253)Group B (non-ART: n=6351)Total (n=6604)Maternal age (y)35.3 ± 3.631.1 ± 4.431.3 ± 4.5Parity (primipara/multipara)197 / 563390 / 29613587 / 3017Velamentous Insertion(VI)11 (4.3%)38 (0.6%)49 (0.7%)Marginal Insertion (MI)38 (15.0%)369 (5.8%)407 (6.2%)Data are mean±SD or number of subject Open table in a new tab Data are mean±SD or number of subject 1) These findings suggest that the ART procedures have a positive correlation on the incidence of abnormal cord insertion (esp. velamentous insertion). 2) ART-conceived cases should be more proactively screened and assessed for insertion site of the umbilical cord during routine obstetric ultrasound examinations, in addition to other already-known ART-associated risk factor assessments, to improve their perinatal outcomes.

Abnormal villous morphology in abortus specimens is not increased in ART pregnancies

Increased incidences of placenta previa, abnormal cord insertion and abruption have been described following ART. Anecdotal experience suggests that abnormal villous morphology (AVM) is diagnosed more frequently in abortuses following ART. AVM specimens have a partial mole-like morphology and equivalent staining, but do not share the fully developed features of a partial mole. Further, AVM seems more frequent in aneuploid pregnancies. The objectives of this study were to determine the prevalence of AVM in ART pregnancies compared to non-ART pregnancies, and the ability of AVM to predict chromosomal abnormalities.

Opening of the uterine isthmus at 11–13 weeks' gestation is not related to developmental abnormalities of the placenta

ObjectivesTo clarify whether openning of the uterine isthmus between 11 and 13weeks' gestation adversely affects the placental development. MethodsThe uterine cervix and isthmus lengths were measured prospectively using transabdominal ultrasound at 11 to 13+6weeks' gestation. Following delivery, the pregnancy and delivery course were reviewed. The associations between the conditions of the uterine isthmus during the first trimester and the perinatal complications associated with placental abnormalities were analyzed. ResultsA total of 653 cases were analyzed. The isthmus had been completely opened (isthmus length=0mm) in 15.9%, 21.6% and 24.1% of the cases at 11, 12 and 13weeks' gestation. The frequencies of perinatal complications in the cases whose isthmus had been opened (cases) and the other cases (controls) were as follows; 1.4% and 1.0% (ns) for placenta previa, 1.4% and 1.2% (ns) for abnormal cord insertion, 3.5% and 4.3% (ns) for pre-eclampsia, 9.9% and 9.0% (ns) for small for gestational age, and 12.0% and 7.6% (ns) for preterm delivery, respectively. ConclusionEarly opening of the uterine isthmus at 11 to 13weeks' gestation does not appear to adversely affect either the placental development or the course of pregnancy.

Vascular Network Features, Separate from Anastomotic Communications, Account for Birthweight Discordance in Monochorionic Placentas

s / Placenta 34 (2013) A1–A99 A13 P1.5. VASCULAR NETWORK FEATURES, SEPARATE FROM ANASTOMOTIC COMMUNICATIONS, ACCOUNT FOR BIRTHWEIGHT DISCORDANCE IN MONOCHORIONIC PLACENTAS Moni Kaneti , Enrico LoPriore , Nadav Schwartz , Dawn Misra , Carolyn Salafia 1,2 1 Placental Analytics LLC, Larchmont, NY, USA; 2 Institute for Basic Research, Staten Island, NY, USA; 3 Leiden University Hospital, Leiden, The Netherlands; University of Pennsylvania SChool of Medicine, Philadelphia PA, USA; Wayne State University, Detroit, MI, USA Goal: The goal of this study was to determine how circulatory anastomoses, structural features of features of the chorionic vascular networks, and umbilical cord inserted were correlated with differences between birth weights, and discordant weights (BWD) in monochorionic (MO) twins. Methods: De-identified images of 44 MO twin placentas with TTTS mild enough to not require laser ablation surgery in utero were traced to detail the arterial (A) and venous (V) networks for 45 pairs of MO twins. A traced placenta yields four images, one of each twin's A and V networks. Vessels 20% and 12 (27% with BWD>25%. All but 7(16%) twins had identifiable anastomoses connecting the two circulations. 32 (71%) had at least one AA anastomoses, while 26 (59%) had AV anastomoses. 8 (18%) had VV anastomoses. AA and VV anastomoses were uncorrelated with BWD. While the presence of any AV anastomoses (v. no AV anastomoses) was uncorrelated with BWD, increasing # AV anastomoses >1 VA anastomosis increased BWD 4.1% (p1⁄40.01) Network structures of larger and smaller twins differed significantly and accounted for 11% of BWD. Umbilical cord insertion site was not correlated in either twin with type or # of anastomoses (each p>0.10, data not shown). Abnormal cord insertions (coded normal, marginal and velamentous) was associated with more sparse surface vessels only in the smaller twin, (data not shown) and remained significant after controlling for the arterial branching density and # of AV anastomoses. Conclusion: Many features of the vascular networks, and particularly arterial networks, were strongly correlated with BWD, including Ă differences in total vascular surface area, branch generations and total number of branch points. Such differences in vascular network structures provide insight into the pathophysiology that can result in drastic differences in fetal development in MO twins. http://dx.doi.org/10.1016/j.placenta.2013.06.042 P1.6. PLACENTAL TERMINALVILLI COMPLEXITY IN CASES OF AUTISM/AUTISM SPECTRUM DISORDER (ASD) AND THEIR MATCHED CONTROLS Carolyn Salafia , George Merz , Craig Platt 3 1 Institute for Basic Research, Staten Island, NY, USA; 2 Placental Analytics LLC, Larchmont, NY, USA; University Hospitals Bristol NHS Foundation Trust,

Vasa Previa

To review experience with diagnosis, clinical associations, and outcomes of vasa previa in a single institution. This was a retrospective review of all identified vasa previa cases from January 1 1990, to June 30, 2010. Sixty cases of vasa previa were identified (53 singletons, seven twins); 56 cases were diagnosed before delivery. An abnormal cord insertion or abnormal placental location was present in 55 cases. Missed diagnoses were attributed to technical and observer factors. Preterm bleeding was encountered in 25 (42%) case group participants. Seven case group participants required an emergent delivery, with significant neonatal morbidity and mortality. Twin pregnancies had a significantly earlier median age at delivery of 32 weeks of gestation compared with 35 weeks of gestations in singletons (P=.01). The seven twin pregnancies had a 28.6% emergent preterm delivery rate, whereas singletons had a 4.1% rate (P=.07). In 14 case group participants, the membranous fetal vessel was located in the lower uterus and not directly over the cervix. The vessel location was not related to the risk of emergent delivery. Transvaginal ultrasound scans of at-risk patients can identify most cases of vasa previa. Preterm bleeding does not usually require immediate delivery. The rate of emergent preterm delivery was low in singleton pregnancies. Twins were delivered, on average, 3 weeks earlier than singletons. III.

Prevalence, Risk Factors and Outcomes of Velamentous and Marginal Cord Insertions: A Population-Based Study of 634,741 Pregnancies

ObjectivesTo determine the prevalence of, and risk factors for anomalous insertions of the umbilical cord, and the risk for adverse outcomes of these pregnancies.DesignPopulation-based registry study.SettingMedical Birth Registry of Norway 1999–2009.PopulationAll births (gestational age >16 weeks to <45 weeks) in Norway (623,478 singletons and 11,263 pairs of twins).MethodsDescriptive statistics and odds ratios (ORs) for risk factors and adverse outcomes based on logistic regressions adjusted for confounders.Main outcome measuresVelamentous or marginal cord insertion. Abruption of the placenta, placenta praevia, pre-eclampsia, preterm birth, operative delivery, low Apgar score, transferral to neonatal intensive care unit (NICU), malformations, birthweight, and perinatal death.ResultsThe prevalence of abnormal cord insertion was 7.8% (1.5% velamentous, 6.3% marginal) in singleton pregnancies and 16.9% (6% velamentous, 10.9% marginal) in twins. The two conditions shared risk factors; twin gestation and pregnancies conceived with the aid of assisted reproductive technology were the most important, while bleeding in pregnancy, advanced maternal age, maternal chronic disease, female foetus and previous pregnancy with anomalous cord insertion were other risk factors. Velamentous and marginal insertion was associated with an increased risk of adverse outcomes such as placenta praevia (OR = 3.7, (95% CI = 3.1–4.6)), and placental abruption (OR = 2.6, (95% CI = 2.1–3.2)). The risk of pre-eclampsia, preterm birth and delivery by acute caesarean was doubled, as was the risk of low Apgar score, transferral to NICU, low birthweight and malformations. For velamentous insertion the risk of perinatal death at term was tripled, OR = 3.3 (95% CI = 2.5–4.3).ConclusionThe prevalence of velamentous and marginal insertions of the umbilical cord was 7.8% in singletons and 16.9% in twin gestations, with marginal insertion being more common than velamentous. The conditions were associated with common risk factors and an increased risk of adverse perinatal outcomes; these risks were greater for velamentous than for marginal insertion.

150: Abnormal placental cord insertion (aPCI) increases risk of umbilical artery (UA) Doppler abnormalities associated with iatrogenic preterm delivery in twins

150: Abnormal placental cord insertion (aPCI) increases risk of umbilical artery (UA) Doppler abnormalities associated with iatrogenic preterm delivery in twins

Expectant management in type II selective intrauterine growth restriction and abnormal chord insertion in monochorionic twins

To assess perinatal outcome in type II monochorionic (MC) diamniotic twin pregnancies (DA) affected by selective intrauterine growth restriction (sIUGR) and abnormal cord insertion managed expectantly. A prospective longitudinal study from June 2008 and July 2011 on 24 MCDA sIUGR twins. sIUGR was defined as estimated fetal weight below the 10th percentile in one twin and was classified into three groups based on umbilical artery (UA) Doppler diastolic flow (I: presence; II: constantly absent/reverse (AEDF/ARED); III: intermittently absent or reverse). Marginal cord insertion was defined as insertion within 2 cm of the placental disc edge, and velamentous insertion as a cord insertion into the fetal membranes. Expectant management was chosen in these twins, and absent or reverse A wave in the ductus venosus (DV) was a criterion for delivery. Neonatal outcome was available for all twins delivered. Pathological examination and vascular cast of placentas were performed in all cases. Fourteen twin pregnancies were type II sIUGR, and ten presented an abnormal umbilical cord insertion. Median gestational age (GA) at diagnosis of sIUGR was 18 weeks' gestation (range 16-20 weeks), and all sIUGR co-twins showed AEDF of UA at a median gestational age of 20 weeks (range 18-22 weeks). Median gestational age at delivery was 30 weeks (range 28-34 weeks) with a median birth weight of 1285 g (range 307-1725 g). pH at birth and base excess (BE) were normal in all IUGR co-twin (pH>7.10, median BE 5.5); Apgar score at 5 min was >7. Perinatal outcome was favorable in all cases. Placental pathological examination confirmed the marginal insertion of the umbilical cord and the absence of anastomosis between the two portions of umbilical insertion. This study highlights that expectant management for sIUGR type II twins with or without an abnormal cord insertion should be a valid option to time delivery for these fetuses as shown by the favorable neonatal outcome.

Abnormalities of the placenta

Normal placental structure and function is essential for a healthy pregnancy; the placenta is responsible for nutrient and oxygen transport, removal of waste products, protection from infection, modulation of the maternal immune system and hormone production to maintain pregnancy. The human placenta is structurally adapted to fulfil this role as it is haemomonochorial, minimising the distance between maternal and fetal circulations to maximise exchange. Disorders of the placenta including: FGR, pre-eclampsia, placental abruption and abnormal (velamentous) cord insertion are associated with over 50% of stillbirths and are frequently cited as the primary cause of death [1-3]. Abnormal placental structure and function significantly increases the risk of stillbirth. Levels of pregnancy associated plasma protein A (PAPP-A) in the lowest 5% and alpha fetoprotein (AFP) in the highest 5% increase the risk of stillbirth by 50-fold and 2.8-fold respectively [4,5]. In women at high-risk of pregnancy complications, abnormal placental structure and/or blood flow seen by ultrasound scan at 19-23 weeks preceded 15 out of 22 stillbirths [6]. There are few studies of microscopic placental structure in stillbirth. However, microscopic structure and cell turnover of the villous trophoblast are disrupted in FGR and pre-eclampsia [7-9]. Evidence from genetic analyses demonstrated that gene imprinting in the placenta is altered in pregnancy loss [10]. The importance of placenta genetics and epigenetics is supported by the observation of increased stillbirth and pregnancy loss in confined placental mosaicism where genetic abnormalities are only present in the placenta [11]. Due to its central role in determining pregnancy outcome, detailed examination of the placenta can give useful information about the cause of stillbirth and is recommended by the Royal College of Obstetricians and Gynaecologists (RCOG), American College of Obstetricians and Gynecologists (ACOG) and Perinatal Society of Australia and New Zealand (PSANZ) [12,13]. Examination of the placenta reduces the proportion of unexplained stillbirths [14]. Consequently, examination of the placenta is one of the most common investigations undertaken after a stillbirth and is one of the most valuable [2,15]. Despite the value of placental examination to identify conditions associated with stillbirth including: fetal thrombotic vasculopathy, chronic intervillositis, villitis, chorioamnionitis, funisitis, infarction, massive perivillous fibrin deposition, villous dysmaturity (increased syncytial knot formation), villous immaturity and cord lesions further research is needed to increase the understanding of placental pathology in stillbirth. This is reflected in the research priorities for high-income countries synthesised by an international panel of experts which mention need for repositories of well-phenotyped samples from stillbirths and from well-matched controls and the need to understand the pathophysiological pathways in common conditions associated with stillbirth including: diabetes, cigarette smoking and maternal obesity [16]. An important goal of translational medicine is to use the increased understanding of placental dysfunction to develop improved tests of pregnancy wellbeing. For example, factors derived from the placenta, such as human placental lactogen or placental growth factor may provide novel means to identify pregnancies at highest risk of stillbirth [17]. Discovery-based technologies such as proteomics or metabolomics offer the opportunity to analyse biofluids and tissue in hypothesis-generating studies to provide a more holistic understanding of fetal and placental dysfunction. Better understanding of the role of the placenta in stillbirth offers the opportunity to develop strategies to identify placental dysfunction in pregnancies, in order that intervention may be targeted to prevent stillbirth.

Umbilical cord accidents

Umbilical cord accidents

Is Assisted Reproduction Associated with Abnormal Placentation?

Artificial reproductive technologies (ART) and conception following a period of untreated infertility (>1 year) are independently associated with increased pregnancy complications in both singleton and multiple pregnancies. It is unknown if placental dysfunction associated with macroscopic and/or microscopic histological discrepancies might explain some of these variances. Our aim was to compare the histopathology of placentae from singleton pregnancies belonging to 3 groups, as follows: conception as a result of ART; spontaneous conception (<1 year of trying); and conception following untreated infertility (>1 year). Pathological examination of placentae from singleton pregnancies of nonsmoking, age-matched primiparous women with no significant medical history and no known uterine congenital anomalies was performed by a single pathologist blinded to the groups. Features were compared using analysis of variance and chi-square tests. A total of 89 placental pathology reports were available (control = 39, infertility = 17, ART = 33). The mean placental thickness was significantly higher in the ART group when compared to the spontaneous conception group (P = 0.02). There were significantly more placental hematomas in the ART group (P = 0.04) compared to the other groups. There were no significant differences in rates of abnormal placental shapes or abnormal cord insertions. There were no statistically significant differences in the incidence of microscopic placental lesions, nor were there any statistically significant differences in the incidence of macroscopic and microscopic placental lesions between the infertility group and the other groups. Placentae of ART pregnancies show significantly increased thickness and a higher incidence of hematomas. Increased placental thickness has previously been linked to increased perinatal risk.

Variety in placental shape: When does it originate?

ObjectivesObservational and empirical evidence suggest that the average placental shape is round with a centrally inserted umbilical cord. Yet variability of shape is common. When in pregnancy do shape and cord insertion variations originate? Materials and methodsPlacental measures from published datasets obtained ultrasonographically at 11–14 weeks and/or at term were correlated. ResultsSignificant correlations were found between the normalized distance of cord insertion to the margin at 11–14 weeks with the same quantity at delivery (r = 0.509, p < 0.0001). First trimester cord marginality was not correlated with two measures of roundness of the delivered placenta (p = 0.448, and p = 0.812). There was a strong correlation between delivered placental thickness and first trimester cord marginality (r = −0.368, p = 0.009). There was a significant relationship between the cord marginality at 11–14 weeks and the mean chorionic vascular density at delivery (r = −0.287, p = 0.015). Placental position in the uterine cavity influences cord marginality at delivery. Modeling suggests that placental growth in the first trimester is non-round. Placental shape at 11–14 weeks is found to be irregular. This irregularity is not correlated with the roundness of the delivered placenta. Both empirically, and in the context of IVF pregnancies, deformation of the vasculogenic zone yields a bi-lobate placental shape. ConclusionsOur findings strongly support the hypothesis that abnormal cord insertion and a multi-lobate shape result from early influences on the placental growth, such as the shape of the vasculogenic zone, or placental position in the uterus, rather than trophotropism later in pregnancy.

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.

OP05.08: Abnormal placental cord insertion in monochorionic‐diamniotic twins: an ominous finding

OP05.08: Abnormal placental cord insertion in monochorionic‐diamniotic twins: an ominous finding

Placental fetal thrombotic vasculopathy in severe congenital anomalies prompting EXIT procedure

Objective The ex-utero intrapartum treatment (EXIT) procedure is used to secure fetal airway, cannulate for extracorporeal membrane oxygenation (ECMO), or resect a tumor during partial delivery in a modified cesarean section. This is a retrospective study of placental pathology from EXIT procedures. Methods Placental reports and glass slides from 36 placentas delivered by EXIT procedure (study group SG) and 36 placentas from pregnancies without perinatal mortality and delivered by cesarean sections and matched for gestational age were blindly reviewed. Indications for EXIT procedures were: 11 cervical teratomas, 9 diaphragmatic hernias, 4 pulmonary airway malformations, 4 micrognathias, 3 vascular malformations, 3 CHAOS, and 2 aortic stenoses. 22 clinical and 43 gross and histological placental features were compared using the analysis of variance or Yates χ 2 with Holm–Bonferroni correction, where appropriate. Results The average gestational age in the SG and the CG was 34.9 weeks. Histological features of fetal thrombotic vasculopathy were more frequently seen in the SG. Of the placental features, statistically significant differences were found in, partial fibrosis of chorionic villi (9.7 ± 7.9 vs. 6.1 ± 5.3 villi per placental section) [ p = 0.035], clusters of at least 3 avascular chorionic villi (33 v. 6%) [ p = 0.042], and abnormal umbilical cord insertion (8% vs. 0% ( p = 0.045), in the SG and the CG respectively. Conclusion To the best of our knowledge, this is the first study to describe the placentas from EXIT procedures. The presence of increased frequency of fetal thrombotic vasculopathy on histology indicates an underlying chronic and on-going stasis in fetal circulation due to the presence of conditions which were indications for the EXIT procedures. The possibility of coagulopathy should be considered in management of the fetuses and neonates undergoing EXIT procedure. Detailed examination of the placenta is of utmost importance in order to recognize and treat potentially life-threatening complications.

370: Impact of abnormal placental cord insertion identified by ultrasound and pathology on neonatal outcomes in twin gestations

370: Impact of abnormal placental cord insertion identified by ultrasound and pathology on neonatal outcomes in twin gestations

Gross Abnormalities of the Umbilical Cord: Related Placental Histology and Clinical Significance

Objective To evaluate umbilical cord abnormalities predisposing to mechanical cord compression and determine their relationship to adverse clinical outcomes and stasis-associated histologic changes in the placenta. Methods Placental slides of 224 singleton pregnancies with gross cord abnormality (true knots, long cords, nuchal/body cords, abnormal cord insertion, hypercoiled cords, narrow cords with diminished Wharton's jelly), delivered on or after 28 weeks gestational age, and 317 gestational age-matched controls, were reviewed and specifically evaluated for the following histologic changes: (1) fetal vascular ectasia, (2) fetal vascular thrombosis, (3) and fetal thrombotic vasculopathy/avascular villi. These changes were analyzed in relation to both clinical information and findings at gross pathologic examination. Results Gross cord abnormalities were associated with stillbirth, intrauterine growth restriction, non-reassuring fetal tracing, meconium-stained amniotic fluid, and increased rate of emergency Cesarean section. At microscopic evaluation, cases with gross cord abnormalities showed a statistically significant association with both ectasia and thrombosis in the fetal vasculature, as well as changes of fetal thrombotic vasculopathy in the terminal villi. When considering individual gross cord abnormalities, long cord and nuchal cord had the highest rates of thrombosis-related histopathology. Finally, cases with both abnormal cords and histologic thrombosis had significantly higher rates of adverse outcomes, including IUGR and stillbirth. Conclusion Gross cord abnormalities predispose the fetus to stasis-induced vascular ectasia and thrombosis, thus leading to vascular obstruction and adverse neonatal outcome, including IUGR and stillbirth. We recommend a thorough histopathologic evaluation of all placentas with gross cord abnormalities predisposing to cord compression.

A piece in the puzzle of intrauterine fetal death: Pathological findings in placentas from term and preterm intrauterine fetal death pregnancies

Objective. To compare pathological findings of placentas from term and preterm pregnancies complicated by intrauterine fetal death (IUFD).Study design. A retrospective cohort study was conducted including deliveries complicated by IUFD. A comparison was made between placentas from term and preterm (<37 weeks' gestation) pregnancies complicated by IUFD. A second analysis was undertaken comparing IUFD placentas delivered before and after 34 weeks' gestation. Uteroplacental insufficiency was defined when one or more of the following pathological features were found: placental infarct, poor vascularity of the chorionic villi, intravascular thrombi and vascular occlusion.Results. During the study period, 849 placentas of IUFD were examined. Gross and microscopic pathological finding were noted. When comparing gross and microscopic findings in term and preterm (<37 weeks) IUFD placentas, higher rates of calcifications, tissue congestion and cellular metaplasia were found in term vs. preterm placentas. Significantly increased rates of poor tissue vascularity, placental vascular occlusion and uteroplacental insufficiency were demonstrated in preterm IUFD placentas. When comparing pathological findings in IUFD placentas delivered before and after 34 weeks' gestation, higher rates of abnormal cord insertion, calcifications, tissue congestion, infarcts and intravascular thrombi as well as poor tissue vascularity and placental vascular occlusion were demonstrated in IUFD placentas delivered before 34 weeks. Regardless of gestational age at the time of IUFD in more than 90% of placentas vascular wall thickening was found. A third of both term and preterm placentas demonstrated histological chorioamionitis.Conclusions. A vast majority of IUFD placentas reveal numerous pathological findings that reflect uteroplacental insufficiency and abnormal blood supply. Different characteristics were noted in term and preterm placentas of pregnancies complicated by IUFD. Better definition of causes and associated placental pathological findings of IUFD might aid clinicians in counseling such patients regarding the reason and risk of recurrence in subsequent pregnancies.

The outcome of twin–twin transfusion syndrome complicated with placental insufficiency

The aim was to evaluate the incidence and perinatal outcomes of TTTS complicated with placental insufficiency (PI/TTTS). This was a retrospective study of all TTTS with PI. PI is defined as estimated fetal weight < 10% with elevated head circumference/abdominal circumference ratio and weight discordance > 20%. Fifty-two out of 270 (19%) pregnancies met criteria. Forty-nine (94.2%) donor twins were diagnosed with PI/TTTS. Fifteen were treated with amnioreduction, 26 with selective fetoscopic laser photocoagulation, 4 with donor intrafetal radiofrequency ablation (RFA), and 7 had expectant management. There was a high incidence of abnormal Dopplers and abnormal placental cord insertion in the donor twin (58% marginal, 35% membranous) with a mean estimated fetoscopic donor placental share of 26.1 +/- 14.3%. There was a significant decrease in the overall donor survival rate of 61% (4 RFA selected donors were excluded) as compared to overall recipient survival rate of 85%, respectively (P = .009). There was no significant difference in donor or recipient survival rate among the treatment groups (P = .058). Placental insufficiency impacts the survival of the affected twins in the setting of TTTS. Studies are needed for appropriate treatment in TTTS with placental insufficiency.