Criteria for placental examination for obstetrical and neonatal providers.

Pathologic examination of the placenta can provide insight into likely (and unlikely) causes of antepartum and intrapartum events, diagnoses with urgent clinical relevance, prognostic information for mother and infant, support for practice evaluation and improvement, and insight into advancing the sciences of obstetrics and neonatology. Although it is true that not all placentas require pathologic examination (although alternative opinions have been expressed), prioritization of placentas for pathologic examination should be based on vetted indications such as maternal comorbidities or pregnancy complications in which placental pathology is thought to be useful for maternal or infant care, understanding pathophysiology, or practice modifications. Herein we provide placental triage criteria for the obstetrical and neonatal provider based on publications and expert opinion of 16 placental pathologists and a pathologists' assistant, formulated using a modified Delphi approach. These criteria include indications in which placental pathology has clinical relevance, such as pregnancy loss, maternal infection, suspected abruption, fetal growth restriction, preterm birth, nonreassuring fetal heart testing requiring urgent delivery, preeclampsia with severe features, or neonates with early evidence of multiorgan system failure including neurologic compromise. We encourage a focused gross examination by the provider or an attendant at delivery for all placentas and provide guidance for this examination. We recommend that any placenta that is abnormal on gross examination undergo a complete pathology examination. In addition, we suggest practice criteria for placental pathology services, including a list of critical values to be used by the relevant provider. We hope that these sets of triage indications, criteria, and practice suggestions will facilitate appropriate submission of placentas for pathologic examination and improve its relevance to clinical care.

Placenta Accreta Spectrum: Correlation between FIGO Clinical Classification and Histopathologic Findings.

OBJECTIVE: Placenta accreta spectrum (PAS) covers a wide spectrum of placental adherence/invasion with varied clinical significance. Histopathologic examination is considered the confirmatory gold standard, but is only obtained sometime after definitive treatment. The International Federation of Gynecology and Obstetrics (FIGO) has published a new clinical classification that can be assigned at delivery, and we aimed to investigate the association between this new FIGO classification and histopathology and also to assess its correlation with maternal outcomes. STUDY DESIGN: We studied a retrospective cohort of 185 patients with histopathologically proven PAS managed at our referral center between September 2012 and January 2019. Two experienced surgeons retrospectively reviewed charts and assigned the FIGO grading based on findings reported at delivery. A third experienced reviewer adjudicated to determine the classification used for final analysis. Categorical outcomes were compared with the use of chi-squared and the Fisher exact test, as appropriate. A multivariate model was designed to adjust outcomes in different FIGO groups for the involvement of a formal multidisciplinary management team. RESULTS: Among 185 patients, there were 41 (22%) placenta accreta, 44 (24%) placenta increta, and 100 (54%) placenta percreta on histopathology. The inter-rater reliability was found to be substantial with Kappa = 0.661 (p < 0.001), and 95% confidence interval (CI): 0.449-0.872. There was a significant association between all histopathology groupings and the FIGO clinical classification (p < 0.001). However, we found no association between FIGO classifications and maternal complications. CONCLUSION: The new FIGO clinical classification is strongly associated with histopathologic findings. A better understanding of the depth and extent of invasion as afforded by the clinical classification system will help standardize reporting and future research. KEY POINTS: · PAS includes a wide spectrum of placental invasion with varied clinical significance.. · Histopathological examination is considered the confirmatory gold standard.. · The new FIGO clinical classification is strongly associated with histopathologic findings..

Basal Plate Myofibers and the Risk of Placenta Accreta Spectrum in the Subsequent Pregnancy: A Large Single-Center Cohort.

OBJECTIVE: We aimed to evaluate whether there is a significant association between a placental pathology diagnosis basal plate myofibers (BPMF) in an index pregnancy with placenta accreta spectrum (PAS) in the subsequent pregnancy. STUDY DESIGN: We conducted a retrospective nested cohort study of all cases with a histopathological finding of BPMF between August 2012 and March 2020 at a single tertiary referral center. Data were collected for all subjects (cases and controls) with at least two consecutive pregnancies (the initial index pregnancy and at least one subsequent pregnancy) accompanied by a concomitant record of histopathological study of the placenta at our center. The primary outcome was pathologically confirmed PAS in the subsequent pregnancy. Data are presented as percentage or median, interquartile range accordingly. RESULTS: A total of n = 1,344 participants were included, of which n = 119 (index cases) carried a contemporaneous histopathological diagnosis of BPMF during the index pregnancy and n = 1,225 did not (index controls). Among the index cases, patients with BPMF were older (31.0 [20, 42] vs. 29.0 [15, 43], p < 0.001), more likely to have undergone in vitro fertilization (IVF) for conception (10.9 vs. 3.8%, p = 0.001) and were of a more advanced gestational age at delivery (39.0 [25, 41] vs. 38.0 [20, 42], p = 0.006). In the subsequent pregnancy, the rate of PAS was significantly higher among the BPMF index cases (6.7 vs. 1.1%, p < 0.001). After adjusting for maternal age and IVF, a histopathological diagnosis of BPMF in an index pregnancy was shown to be a significant risk factor for PAS in the subsequent gestation (hazard ratio: 5.67 [95% confidence interval: 2.28, 14.06], p < 0.001). CONCLUSION: Our findings support that a histopathological diagnosis of BPMF is an independent risk factor for PAS in the subsequent pregnancy. KEY POINTS: · BPMF may indicate morbid adherence of placenta.. · Patients with BPMF were older and more likely to have undergone IVF for conception.. · The BPMF in the current pregnancy is an independent risk factor for PAS in the subsequent pregnancy..

The Society for Pediatric Pathology Task Force grading system for placenta accreta spectrum and its correlation with clinical outcomes.

BACKGROUND: The terminology and diagnostic criteria presently used by pathologists to report placenta accreta spectrum is inconsistent and does not reflect current knowledge of the pathogenesis of this disease. OBJECTIVE: In 2020, the perinatal subcommittee of the Society for Pediatric Pathology Placenta Accreta Task Force proposed a new pathologic grading system for placenta accreta spectrum. We sought to correlate the clinical outcomes with the classification into each group in the new placenta accreta spectrum grading system. STUDY DESIGN: The pathology reports of patients with histopathologic confirmation of placenta accreta spectrum were reviewed in 2 academic referral centers by placental pathologists. Pathologic grading was assigned based on the new grading system according to which placenta accreta spectrum is categorized into 5 groups depending on the depth of invasion, from grade p1 with no invasion into the uterine wall to grade p3E with invasion beyond the uterine wall to the adjacent organs. Patient characteristics and clinical outcomes were compared among these groups. A univariate analysis was performed, and a multivariate linear or binomial regression was employed when needed. RESULTS: A total of 683 patients with placenta accreta spectrum were identified. Of those, 407 were included for histology review. There were 92 patients (23%) categorized into the grade p1 group, 74 (18%) in the grade p2 group, 84 (20%) in the grade p3A group, 121 (30%) in the grade p3D group, and 36 (9%) in the grade p3E group. There was a significant association between the pathology grading and the number of red blood cells transfused (ß=1.14; 95% confidence interval, 0.48-1.79) and the postoperative complications including the rate of readmission (risk ratio, 1.93; 95% confidence interval, 1.26-2.94) and bladder injury (risk ratio, 1.81; 95% confidence interval, 1.23-2.68) after adjustment for antenatal diagnosis and other variables. The pathology grading was not associated with the estimated blood loss (P=.072). CONCLUSION: The new pathology grading system accurately reflects maternal outcomes and complications of placenta accreta spectrum. We encourage the utilization of this new pathologic grading system because it is designed to omit discrepancies in placenta accreta spectrum reporting and to standardize communication.

Placental Vascular and Inflammatory Findings from Pregnancies Diagnosed with Coronavirus Disease 2019: A Systematic Review and Meta-analysis.

We aimed to perform a meta-analysis of the literature concerning histopathologic findings in the placentas of women with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection during pregnancy. Searches for articles in English included PubMed, Web of Science, Google Scholar, and reference lists (up to April 2021). Studies presenting data on placental histopathology according to the Amsterdam Consensus Group criteria in SARS-CoV-2 positive and negative pregnancies were identified. Lesions were categorized into: maternal and fetal vascular malperfusion (MVM and FVM, respectively), acute placental inflammation with maternal and fetal inflammatory response (MIR and FIR, respectively), chronic inflammatory lesions (CILs), and increased perivillous fibrin deposition (PVFD). A total of 15 studies reporting on 19,025 placentas, n = 699 of which were derived from women who were identified as being infected with SARS-CoV-2 and 18,326 as SARS-CoV-2-negative controls, were eligible for analysis. No significant difference in incidence of MVM (odds ratio [OR]: 1.18, 95% confidence interval [CI]: 0.73-1.90), FVM (OR: 1.23, 95% CI: 0.63-2.42), MIR (OR: 0.66, 95% CI: 0.29-1.52) or FIR (OR: 0.85, 95% CI: 0.44-1.63), and CILs (OR: 0.97, 95% CI: 0.55-1.72) was found between placentae from gravida identified as being SARS-CoV-2 infected. However, placenta from gravida identified as being infected with SARS-CoV-2 were associated with significantly increased occurrence of PVFD (OR: 2.77, 95% CI: 1.06-7.27). After subgroup analyses based on clinical severity of COVID-19 infection, no significant difference was observed in terms of reported placental pathology between symptomatic or asymptomatic SARS-CoV-2 gravidae placenta. Current evidence based on the available literature suggests that the only pathologic finding in the placentae of women who are pregnant identified as having been infected with SARS-CoV-2 was an increased prevalence of PVFD. KEY POINTS: · No association between SARS-CoV-2 and maternal or fetal placental malperfusion.. · No association between SARS-CoV-2 and maternal or fetal inflammatory response.. · SARS-CoV-2 is associated with increased perivillous fibrin deposition in placenta..

Sox9 Is a Modifier of the Liver Disease Severity in a Mouse Model of Alagille Syndrome.

BACKGROUND AND AIMS: Alagille syndrome (ALGS) is a multisystem developmental disorder characterized by bile duct (BD) paucity, caused primarily by haploinsufficiency of the Notch ligand jagged1. The course of the liver disease is highly variable in ALGS. However, the genetic basis for ALGS phenotypic variability is unknown. Previous studies have reported decreased expression of the transcription factor SOX9 (sex determining region Y-box 9) in late embryonic and neonatal livers of Jag1-deficient mice. Here, we investigated the effects of altering the Sox9 gene dosage on the severity of liver disease in an ALGS mouse model. APPROACH AND RESULTS: Conditional removal of one copy of Sox9 in Jag1+/- livers impairs the biliary commitment of cholangiocytes and enhances the inflammatory reaction and liver fibrosis. Loss of both copies of Sox9 in Jag1+/- livers further worsens the phenotypes and results in partial lethality. Ink injection experiments reveal impaired biliary tree formation in the periphery of P30 Jag1+/- livers, which is improved by 5 months of age. Sox9 heterozygosity worsens the P30 biliary tree phenotype and impairs the partial recovery in 5-month-old animals. Notably, Sox9 overexpression improves BD paucity and liver phenotypes in Jag1+/- mice without ectopic hepatocyte-to-cholangiocyte transdifferentiation or long-term liver abnormalities. Notch2 expression in the liver is increased following Sox9 overexpression, and SOX9 binds the Notch2 regulatory region in the liver. Histological analysis shows a correlation between the level and pattern of SOX9 expression in the liver and outcome of the liver disease in patients with ALGS. CONCLUSIONS: Our results establish Sox9 as a dosage-sensitive modifier of Jag1+/- liver phenotypes with a permissive role in biliary development. Our data further suggest that liver-specific increase in SOX9 levels is a potential therapeutic approach for BD paucity in ALGS.

Massive Extra-Abdominal Umbilical Vein Varix: A Case Report.

Umbilical vein varices are rare umbilical cord anomalies that typically occur intra-abdominally. Extra-abdominal umbilical vein varices are exceedingly rare and usually diagnosed postnatally on gross pathologic examination. Umbilical vein varices have been associated with increased risk of fetal anemia, cardiac abnormalities, and intrauterine fetal demise. This case report discusses a patient who presented with a massive extra-abdominal umbilical vein varix, whose infant was ultimately delivered due to fetal distress and died in the neonatal period. This report also discusses associated fetal conditions and guidelines for antenatal testing and surveillance of known umbilical vein varices.

Visualization of microbes by 16S in situ hybridization in term and preterm placentas without intraamniotic infection.

BACKGROUND: Numerous reports have documented bacteria in the placental membranes and basal plate decidua in the absence of immunopathology using histologic techniques. Similarly, independent metagenomic characterizations have identified an altered taxonomic makeup in association with spontaneous preterm birth. Here we sought to corroborate these findings by localizing presumptive intact bacteria using molecular histology within the placental microanatomy. OBJECTIVE: Here we examined for microbes in term and preterm gestations using a signal-amplified 16S universal in situ hybridization probe set for bacterial rRNA, alongside traditional histologic methods of Warthin-Starry and Gram stains, as well as clinical culture methodologies. We further sought to differentiate accompanying 16S gene sequencing taxonomic profiles from germ-free (gnotobiotic) mouse and extraction and amplicon contamination controls. STUDY DESIGN: Placentas were collected from a total of 53 subjects, composed of term labored (n = 4) and unlabored cesarean deliveries (n = 22) and preterm vaginal (n = 18) and cesarean deliveries (n = 8); a placenta from a single subject with clinical and histologic evident choriomanionitis was employed as a positive control (n = 1). The preterm cohort included spontaneous preterm birth with (n = 6) and without (n = 10) preterm premature rupture of membranes, as well as medically indicated preterm births (n = 10). Placental microbes were visualized using an in situ hybridization probe set designed against highly conserved regions of the bacterial 16S ribosome, which produces an amplified stable signal using branched DNA probes. Extracted bacterial nucleic acids from these same samples were subjected to 16S rRNA metagenomic sequencing (Illumina, V4) for course taxonomic analysis, alongside environmental and kit contaminant controls. A subset of unlabored, cesarean-delivered term pregnancies were also assessed with clinical culture for readily cultivatable pathogenic microbes. RESULTS: Molecular in situ hybridization of bacterial rRNA enabled visualization and localization of low-abundance microbes after systematic high-power scanning. Despite the absence of clinical or histologic chorioamnionitis in 52 of 53 subjects, instances of 16S rRNA signal were confidently observed in 13 of 16 spontaneous preterm birth placentas, which was not significantly different from term unlabored cesarean specimens (18 of 22; P > .05). 16S rRNA signal was largely localized to the villous parenchyma and/or syncytiotrophoblast, and less commonly the chorion and the maternal intervillous space. In all term and unlabored cesarean deliveries, visualization of evident placental microbes by in situ hybridization occurred in the absence of clinical or histologic detection using conventional clinical cultivation, hematoxylin-eosin, and Gram staining. In 1 subject, appreciable villous bacteria localized to an infarction, where 16S microbial detection was confirmed by Warthin-Starry stain. In all instances, parallel sample principle coordinate analysis using Bray-Cutis distances of 16S rRNA gene sequencing data demonstrated consistent taxonomic distinction from all negative or potential contamination controls (P = .024, PERMANOVA). Classification from contaminant filtered data identified a distinct taxonomic makeup among term and preterm cohorts when compared with contaminant controls (false discovery rate <0.05). CONCLUSION: Presumptively intact placental microbes are visualized as low-abundance, low-biomass and sparse populations within the placenta regardless of gestational age and mode of delivery. Their taxonomic makeup is distinct from contamination controls. These findings further support several previously published findings, including our own, which have used metagenomics to characterize low-abundance and low-biomass microbial communities in the placenta.

Hepatic Steatosis Is Prevalent Following Orthotopic Liver Transplantation in Children With Cystic Fibrosis.

OBJECTIVES: Systematic study of allograft liver histology in children undergoing orthotopic liver transplantation (LT) for cystic fibrosis-related liver disease (CFLD). METHODS: Retrospective clinicopathologic review of explants and allograft liver biopsies from 13 children and adolescents with CFLD. RESULTS: In this study, the median age at LT for CFLD was 15.7 years. Notably, 10 of 13 (77%) CF explants had >5% steatosis and 8 of 13 (61.5%) demonstrated variable fibrosis. The median age, sex, type of transplant (liver vs liver-lung), pancreatic insufficiency status, body mass index (BMI) percentile, genotype, and prevalence of diabetes were comparable in those with and without explant steatosis. More than half of allograft biopsies showed significant steatosis (17/31, 54.8%) and lobular inflammation (16/31, 51.6%). Hepatocyte ballooning was less frequent (5/31, 16.1%). Overall, 6 patients (46.2%) had allograft steatosis that worsened over time in 2 patients (33%). None had advanced fibrosis (≥stage 3). Patients with allograft steatosis had significantly more biopsies, were more likely to be "liver only" recipients, had a shorter interval since transplant and higher body mass index percentile (although <85). Patients without explant steatosis never demonstrated allograft steatosis, whereas 60% of patients with explant steatosis (n = 6) developed varying degrees of allograft steatosis. The degree of explant steatosis did not predict its severity in allografts (P = 0.3). CONCLUSION: This is the first study highlighting the development of allograft steatosis in CF patients. Our findings suggest that allograft steatosis in patients with CF may be related to pre-existing steatosis in native livers, regardless of other risk factors and may have implications on patient management and long-term graft/patient survival.

Extrahepatic Nonreticuloendothelial Siderosis Is Not Specific to Gestational Alloimmune Liver Disease.

Autopsy reports of 78 stillbirths and early infant deaths (up to age 8 weeks) were reviewed to investigate the prevalence of extrahepatic nonreticuloendothelial siderosis (EHNRS) in the context of neonatal liver failure. Of these, 10 liveborns (12.8%), M:F 3:2, with mean gestational age 37.6 weeks (range: 35-39) and mean age at the time of demise 19.1 days (range: 7-42), showed significant liver injury: infection (n = 7, viral > fungal), congenital malformations (n = 2), and ischemia (n = 1). None had maternal history of gestational alloimmune liver disease (GALD) or previous fetal/neonatal death due to liver failure. Seven of 10 cases (70%) showed EHNRS: pancreas (n = 6), kidneys (n = 4), thyroid and adrenal glands (n = 3), and bronchial glands and heart (n = 2). Iron deposition was most frequent in the pancreas (60%), most diffuse in the kidneys, and seen in at least 2 organs, with pancreas and kidney being the most frequent combination. Hepatic C5b-9 expression was variable (1+ to 4+) except 1 case (100% necrosis). The duration of illness and the mean age at the time of demise tended to be higher in those with EHNRS. In summary, hepatic and EHNRS, with or without C5b-9 expression, are not specific for GALD. Other causes of liver failure should be investigated as clinically and pathologically appropriate.

Amniotic membrane and placental histopathological findings after open and fetoscopic prenatal neural tube defect repair.

OBJECTIVES: To describe and compare placental and amniotic histology in women who underwent a fetoscopic myelomeningocele repair to those who underwent an open hysterotomy myelomeningocele repair. Also, we intended to compare findings from both prenatal repair groups to age-matched control pregnant patients. METHODS: Placental and membrane histopathology from 43 prenatally repaired spina bifida cases (17 fetoscopic and 26 open) and 18 healthy controls were retrospectively assessed. Quantitative assessment of histopathology included apoptosis count and maternal and fetal underperfusion scores. Qualitative assessment included the detection of pigmented macrophages and/or signs of placental/amniotic inflammation. Associations between the duration of surgery or the duration of CO2 insufflation and quantitative histological parameters were tested. RESULTS: Fetoscopic surgery cases did not show significant differences in any of the studied parameters when compared against controls. No differences were detected either when compared with open repaired cases, except for lower proportion of pigmented laden macrophages in the fetoscopic group (11.8% vs 61.5%, P < 0.01). No associations between the duration of surgery or the duration of CO2 exposure and any of the quantitative histological parameters were detected. CONCLUSIONS: These preliminary results support the lack of detrimental effects of the use of heated and humidified CO2 gas for uterine insufflation to fetal membranes and placenta.

Cervical lymphatic malformations: Prenatal characteristics and ex utero intrapartum treatment.

BACKGROUND: The ex utero intrapartum treatment (EXIT) is utilized to transition fetuses with prenatally diagnosed airway obstruction to postnatal life. We describe the unique clinical course, diagnosis, treatment, and outcomes of patients with cervical lymphatic malformation (CLM) managed with EXIT. METHODS: Review of fetuses with diagnosed CLM was delivered by EXIT (2001-2018) in a tertiary referral fetal center. Outcomes included survival, tracheostomy at discharge, neonatal course after delivery, and pulmonary hypoplasia. Data are reported as median [range] and rate (%). RESULTS: Out of 45 patients delivered by EXIT, 10 were delivered for CLM: seven had polyhydramnios, one had nonimmune hydrops, five delivered preterm, and three were emergency EXITs. The EXIT time and estimated blood loss were 125 minutes (95, 158) and 900 mL (500, 1500), respectively. Airway was secured in all. There was one neonatal death (day 8) with prematurity, sepsis, and pulmonary hypoplasia. Three out of nine were discharged with a tracheostomy. CONCLUSION: In CLM, close monitoring for structural neck involvement and development of polyhydramnios are important and may be an indication for EXIT as the optimal delivery mode. An experienced multidisciplinary team is a key factor for an effective approach to the obstructed airway in CLM.

Characterization of Placental Microvasculature Using Superb Microvascular Imaging.

Superb Microvascular Imaging (SMI; Canon Medical Systems, Tustin, CA) uses clutter suppression to extract flow signals at rapid frame rates, which provides high-resolution vessel-branching details without the need for contrast agents. The potential diagnostic benefits of SMI, as described in other areas of medicine, requires further exploration during pregnancy. In this pictorial essay, we demonstrate the complementary use of SMI compared to conventional Doppler ultrasound and how it may improve our ability to characterize placental microvascular patterns without the need for ultrasound contrast agents.

Clinical Importance of Placental Testing among Suspected Cases of Congenital Zika Syndrome.

Contemporaneous Zika virus (ZIKV) strains can cause congenital Zika syndrome (CZS). Current ZIKV clinical laboratory testing strategies are limited and include IgM serology (which may wane 12 weeks after initial exposure) and nucleic acid testing (NAT) of maternal serum, urine, and placenta for (+) strand ZIKV RNA (which is often transient). The objectives of this study were to determine if use of additional molecular tools, such as quantitative PCR and microscopy, would add to the diagnostic value of current standard placental ZIKV testing in cases with maternal endemic exposure and indeterminate testing. ZIKV RNA was quantified from dissected sections of placental villi, chorioamnion sections, and full cross-sections of umbilical cord in all cases examined. Quantitation with high-resolution automated electrophoresis determined relative amounts of precisely verified ZIKV (74-nt amplicons). In order to localize and visualize stable and actively replicating placental ZIKV in situ, labeling of flaviviridae glycoprotein, RNA ISH against both (+) and (⁻) ZIKV-specific ssRNA strands, and independent histologic examination for significant pathologic changes were employed. We demonstrate that the use of these molecular tools added to the diagnostic value of placental ZIKV testing among suspected cases of congenital Zika syndrome with poorly ascribed maternal endemic exposure.

Association between the macroscopic characteristics of the umbilical cord, high-risk pregnancy and neonatal repercussions. / Associação entre as características macroscópicas do cordão umbilical, gestação de alto risco e repercussões neonatais.

OBJECTIVE: To verify the association between the macroscopic characteristics of the umbilical cord, high-risk pregnancy and neonatal repercussions. METHOD: A cross-sectional study carried out from January 2012 to January 2015 in a public maternity hospital in Goiânia/GO. The study population consisted of 126 recent puerperal women with diagnosis of high-risk pregnancy, and 139 clinically normal women (control group). Macroscopic features of the umbilical cord, maternal, fetal and neonatal diseases, gestational age, Apgar score, birth weight, head circumference and parity were evaluated. Data were descriptively analyzed. RESULTS: 265 puerperal women and their respective newborns participated in the study. The most frequent characteristics of the umbilical cord of those with high-risk pregnancy and those from the control group were the absence of true knots (97.6% and 2.4%, respectively), length between 35 and 70 centimeters and paracentral insertion (81.7% and 18.3%). A statistical difference was observed between the high-risk pregnancy group and extremes of maternal age (p=0.004). CONCLUSION: The analysis and description of the characteristics of the umbilical cord carried out by the nurse lend important information about the neonatal prognosis. This evaluation subsidizes clinical practice and seeks to ensure the safety of the (mother-baby) binomial throughout the perinatal period.

Umbilical Cord Coiling and Zygosity: Is there a Link?

INTRODUCTION: The aim of this study was to analyze abnormalities of umbilical coiling index (UCI) in twin gestation to test whether the coiling is genetically influenced by zygosity. METHODS: Data retrieved comprised gestational age (GA), chorionicity, fetal gender, and UCI. RESULTS: The mean UCI of hypercoiled cords in monochorionic placentas was 0.55 coils/cm and 0.49 coils/cm in dichorionic placentas with discordant fetal gender (P = 0.2629). DISCUSSION: In conclusion, no significant statistical difference between UCI in monochorionic and dichorionic twin placentas with discordant fetal gender was identified, suggesting that zygosity does not play a role in umbilical coiling induction.