Marginal Cord Insertion Research Articles

Risk Factors of Marginal Cord Insertion in Singleton Pregnancies: A Systematic Review and Meta-Analysis

Background: Marginal cord insertion (MCI) is increasingly recognized as a pathological variation that necessitates early diagnosis. Identifying the risk factors associated with MCI is essential for improving prenatal screening and optimizing management strategies. Our meta-analysis systematically and quantitatively synthesizes the current evidence on various potential risk factors for MCI. Methods: This systematic review and meta-analysis adhered to the PRISMA and MOOSE guidelines. Comprehensive searches were performed in three databases up until 6 May 2024, identifying observational cohort and case–control studies that examined risk factors for MCI in singleton pregnancies compared with central or eccentric cord insertion. Quality and risk of bias assessment were performed using the Newcastle–Ottawa Scale and the Quality In Prognosis Studies tool, respectively. Statistical analyses employed random-effects models to calculate relative risks (RR) and mean differences with their 95% confidence intervals (95% CI). Heterogeneity was assessed via Cochran’s Q and I2 statistics. Results: A total of 18 studies (14 cohort and 4 case–control), encompassing 51,463 MCI cases and 901,020 control cases, were included. The meta-analysis revealed a prevalence of MCI at 5.71% among singleton pregnancies. Significant risk factors for MCI included the use of assisted reproductive technology (RR = 1.55; 95% CI: 1.34–1.78), chronic hypertension (RR = 1.47; 95% CI: 1.11–1.95), placenta previa (RR = 1.83; 95% CI: 1.62–2.08), and nulliparity (RR = 1.18; 95% CI: 1.08–1.30). No significant associations were found for smoking, maternal age, prior Cesarean section, preexisting diabetes, or Caucasian ethnicity. Sensitivity analyses corroborated the robustness of these findings. Conclusions: This meta-analysis identified assisted reproductive technology, chronic hypertension, placenta previa, and nulliparity as significant risk factors for marginal cord insertion in singleton pregnancies. These findings can inform the development of prenatal screening protocols and enable targeted screenings for high-risk populations.

Magnetic resonance imaging diagnosis of abnormal placental cord insertions

IntroductionAbnormal placental cord insertions (APCIs) are significant risk factors for pregnancy complications, encompassing marginal cord insertion (MCI), velamentous cord insertion (VCI), and vasa previa (VP). While ultrasound is the primary imaging modality, its accuracy can be limited by factors such as maternal obesity and fetal positioning. Complementary to ultrasound, magnetic resonance imaging (MRI) offers a more precise visualization of the fetus, placenta, and umbilical cord relationships. This study aims to investigate the diagnostic value of prenatal magnetic resonance imaging (MRI) for APCIs compared with prenatal ultrasound. MethodsWe retrospectively collected data from 613 patients who underwent prenatal placental ultrasound and MRI. Of those who were confirmed as APCIs through surgery or pathology, the prenatal MRI features were compared with prenatal ultrasound. The diagnostic efficacy of prenatal MRI and ultrasound for APCIs was assessed based on the clinicopathological findings. ResultsFifty-six patients were confirmed as APCIs by surgery or pathology, comprising 31 marginal cord insertions (MCIs), 18 velamentous cord insertions (VCIs), 5 vasa previa (VP) cases, and 2 VCI cases combined with VP. Ultrasound examination showed 55.36 % sensitivity (31/56) and 98.38 % specificity (486/494) in diagnosing APCIs, whereas MRI demonstrated 87.50 % sensitivity (49/56) and 98.88 % specificity (531/537). ConclusionFor APCIs complicated by placental location or morphological abnormalities, MRI demonstrates superior diagnostic efficacy compared to ultrasound in late pregnancy.

O-156 Trophectoderm biopsy for pre-implantation genetic testing (PGT) does not increase rates of placental abnormalities among singleton pregnancies conceived with in-vitro fertilization (IVF)

Abstract Study question Does trophectoderm biopsy for PGT affect placental pathology? Summary answer Trophectoderm biopsy does not increase rates of placental abnormalities among singleton pregnancies conceived with in-vitro fertilization (IVF). What is known already PGT, routinely performed at the blastocyst stage, is used to screen embryos for aneuploidy, structural rearrangements, and single-gene disorders. The association of ART with abnormal placentation and adverse pregnancy outcomes is known. Whether, in a similar fashion, the disruption of the trophectoderm contributes to increased rates of abnormal placentation, remains unknown. Study design, size, duration Data from 987 singleton livebirths with available placental pathology, who conceived following IVF/±PGT at a single academic fertility center between 01/2004 and 12/2019, were retrospectively reviewed. Placental abnormalities were classified as anatomic, inflammatory, infectious, and vascular (any features of fetal or maternal vascular malperfusion), by one expert perinatal pathologist using the Amsterdam Workshop Consensus definitions. Placental pathology was compared between PGT (n = 76) and non-PGT (fresh and frozen, n = 911) cycles. Participants/materials, setting, methods Primary Outcome Measures: incidence of anatomic, vascular (maternal and fetal side), infectious, and inflammatory placental abnormalities. Odds ratios (OR) and 95% confidence intervals (95%CI) were calculated using generalized estimating equations regression to adjust for multiple deliveries per patient and for potential confounders [maternal age, body mass index (BMI:kg/m2), race, parity, infertility diagnosis, gestational age, infant gender, hypertensive disorders of pregnancy, IVF and FET protocol]. Main results and the role of chance Patients undergoing PGT were older than the non-PGT group [36.2(3.5) vs. 34.9(3.8) years, p = 0.006] and did not otherwise differ in AMH, BMI, and race. Overall, adjusted (Adj) OR (95%CI) did not reveal any differences between groups in anatomic [0.92(0.82-1.03)], inflammatory [1.03 (0.94-1.14)]), infectious [1.02 (0.9-1.16)], or vascular abnormalities [1.02(0.88-1.18)]. When limiting analysis to blastocyst biopsies/FET cycles only, adjOR did not show any differences in inflammatory [1.01 (0.89-1.13)]), infectious [1.02 (0.88-1.17)], or vascular abnormalities [1.01 (0.84-1.2)] between the PGT and non-PGT group. Interestingly, adjOR (95%CI) revealed lower odds for anatomic abnormalities in the PGT group (0.86 (0.76-0.98), p = 0.021, non-PGT: ref). A sub-analysis of programmed FET cycles revealed persistently lower odds of anatomic abnormalities among the PGT group [adjOR (95%CI): 0.77 (0.67-0.89), p < 0.001, non-PGT: ref]. Among anatomic abnormalities studied in the programmed FET cycles, marginal cord insertion showed a difference between the groups [adjOR(95%CI): 0.83 (0.73-0.95), p:0.007, non-PGT: ref ]. AdjOR(95%CI) showed no differences in inflammatory [ 1.01 (0.87-1.17)], infectious [1.01 (0.86-1.2)], and vascular [0.9 (0.73-1.1)] abnormalities between groups. Limitations, reasons for caution This study is limited by its retrospective nature. Although a large number of IVF placentas was included, the number of patients in the PGT compared to the non-PGT group was smaller potentially limiting our ability to detect subtle differences between groups. Wider implications of the findings Trophectoderm biopsy for PGT does not appear to increase risk for placental abnormalities, a reassuring finding given the increased incidence of abnormal placentation and adverse perinatal outcomes among IVF pregnancies. Trial registration number not applicable

Marginal cord insertion in the first trimester is associated with furcate cord insertion

ObjectivesTo evaluate the potential connections between marginal cord insertion during the first trimester and furcate cord insertion later in pregnancy.MethodsThis is a prospective study of screening data on the cord insertion site in 3178 singleton pregnancies. The cord insertion site was examined in two stages. The first stage was screening for the cord insertion site between 10–13 weeks of gestation, the purpose is to determine the category of umbilical cord insertion. The second stage, performed at 22–28 weeks of gestation, was to follow up on the relationship between the cord insertion site and the placenta and to identify any changes in the category of umbilical cord insertion. This was performed to diagnose or exclude furcate cord insertion by identifying whether the umbilical cord trunk separated or branched before it reached the placenta. Factors influencing progression to furcate cord insertion and perinatal complications were assessed.ResultsFourteen cases (0.44%) with progression to furcate cord insertion, all of which showed marginal cord insertion on ultrasound in the first trimester (p < 0.001). without progression to furcate cord insertion, there were no changes in the category of umbilical cord insertion in 3050 cases (96.40%) compared to the early pregnancy. 114 cases (3.60%) with changes in the category of umbilical cord insertion that was not consistent with furcate cord insertion. A total of 14 cases progressed to furcate cord insertion, all showed the cord insertion site were in close proximity, and 11 (78.57%) cases showed a low insertion site (p < 0.001). Regarding the choice of mode of delivery, elective caesarean delivery was done in 8/14 (57.14%). The incidences of spontaneous vaginal delivery were 5/14 (35.71%) (p < 0.001). One (7.14%) case of progression to furcate cord insertion due to haematoma at the root of the umbilical cord ended with an emergency caesarean section. In terms of perinatal complications, marginal cord insertion that progressed to furcate cord insertion had higher incidences of SGA infants, abnormal placental morphology, retention of the placenta, and cord-related adverse pregnancy outcomes than not progressed to furcate cord insertion (p < 0.05).ConclusionsMarginal cord insertion in the first trimester has the potential to progress to furcate cord insertion. We suggest that ultrasound-diagnosed marginal cord insertion in the first trimester should be watched carefully in the second trimester, which is clinically useful to accurately determine the category of cord insertion and to improve the rate of prenatal diagnosis of furcate cord insertion.

Marginal cord insertion in placenta and true knot in umbilical cord: a case report

Background: The fetus and placenta are connected by the umbilical cord. Atypical cord attachment that occurs during pregnancy is called marginal cord insertion. However, placing the umbilical cord usually does not cause problems when a woman is pregnant. This study reported a case of marginal cord insertion in the placenta and a true knot in the umbilical cord. Case Presentation: We reported a case of a 39-year-old pregnant woman who was found to have an umbilical cord attached to the edge of the placenta on ultrasound in a singleton pregnancy. The appearance of the umbilical cord insertion was at the edge of the placenta, and there is a true knot in the umbilical cord that was not diagnosed during pregnancy.The incidence of true umbilical cord knots has been found to range from 0.04% to 3%. They are linked to four times the risk of stillbirth and significant perinatal morbidity (11%) rates. A four-dimensional and color Doppler examination is essential to diagnose a real umbilical cord. A more thorough examination of the anomaly and repeated confirmation with power and color Dopplers are required for an accurate diagnosis. Conclusion: We reported a case of a 39-year-old pregnant woman who was found to have an umbilical cord attached to the edge of the placenta on ultrasound in a singleton pregnancy. The appearance of the umbilical cord insertion is at the edge of the placenta, and there is a true knot in the umbilical cord that is not diagnosed during pregnancy.

Association between placental location and cord insertion site with pre-eclampsia: a retrospective cohort study

Objective The relationship between placental location in pregnancies without previa and adverse pregnancy outcomes has not been well studied. Additionally, the impact of abnormal cord insertion sites remains controversial. Therefore, the objective of this study was to explore the adverse outcomes associated with placental location and abnormal cord insertion in nulliparous women and to assess their impact on pregnancy outcomes. Methods This retrospective cohort study was conducted at a single tertiary hospital between January 2019 and June 2022. The study included nulliparous women with singleton pregnancies who delivered live infants and had available data on placental location and umbilical cord insertion site from a second- or third-trimester ultrasound. Placental location was categorized as anterior or posterior using transabdominal ultrasonography. The association between placental location/cord insertion site and pre-eclampsia was evaluated using multivariate logistic regression analysis. We compared the area under the curve to evaluate the impact of placental location and cord insertion site on pre-eclampsia. Results A total of 2219 pregnancies were included in the study. Pre-eclampsia occurred significantly more frequently in the anterior group than in the posterior group (8.21% vs. 3.04%, p < .001). In multivariate analysis investigating the association between placental location and pre-eclampsia, anterior placenta and marginal cord insertion showed increased odds ratios for pre-eclampsia of 3.05 (95% confidence interval [CI] 1.68–6.58) and 3.64 (95% CI 1.90–6.97), respectively. Receiver operating characteristic (ROC) curves were constructed to predict pre-eclampsia using independent factors from multivariate analyses. Model I, including maternal age, pre-pregnancy body mass index, in vitro fertilization, chronic hypertension, overt diabetes, kidney disease, and hematologic diseases, achieved an area under the ROC curve of 0.70 (95% CI 0.65–0.75). Adding cord insertion site and placental location to the model (Model II) improved its predictive performance, resulting in an area under the ROC curve of 0.749 (95% CI 0.70–0.79, p = .02). Conclusions Anterior placenta and marginal cord insertion were associated with an increased risk of pre-eclampsia. Further studies on prospective cohorts are necessary to validate these findings.

Associations between velamentous or marginal cord insertion and risk of adverse perinatal outcomes in twin pregnancies: a retrospective cohort study

BackgroundVelamentous cord insertion (VCI) and marginal cord insertion (MCI) are well-known risk factors for adverse perinatal outcomes in singleton pregnancies. However, the potential links between VCI or MCI and perinatal outcomes in twin pregnancies have yet to be systematically evaluated. This study aimed to investigate the relationships between VCI or MCI and perinatal outcomes in twin pregnancies.MethodsThis retrospective single-center cohort study included women with twin pregnancies who gave birth in a tertiary hospital in Southwest, China between January 2017 and December 2022. VCI and MCI were identified by abdominal ultrasound and confirmed after placental delivery. Logistic regression, multinomial logit regression and generalized estimation equation models were used to evaluate the association between VCI or MCI and perinatal outcomes.ResultsA total of 3682 twin pregnancies were included, including 100 (2.7%) pregnancies with VCI and 149 (4.0%) pregnancies with MCI. Compared to pregnancies with normal cord insertion, both monochorionic and dichorionic pregnancies with VCI were associated with an increased risk of preterm delivery 32–34 weeks (aRRR 2.94, 95% CI 1.03–8.39; aRRR 2.55, 95% CI 1.19–5.46, respectively), while pregnancies with MCI were not associated with preterm delivery. VCI was associated with a higher incidence of placental previa (aOR 6.36, 95% CI 1.92–21.04) in monochorionic pregnancies and placental accreta (aOR 1.85, 95% CI 1.06–3.23) in dichorionic pregnancies. MCI was associated with an increased risk of preeclampsia (aOR 3.07, 95% CI 1.49–6.32), intertwin birthweight discordance ≥ 20% (aOR 2.40, 95% CI 1.08–5.60) and selective fetal growth restriction (aOR 2.46, 95% CI 1.08–5.60) in monochorionic pregnancies and small-for-gestational age neonates (aOR 1.97, 95% CI 1.24–3.14) in dichorionic pregnancies.ConclusionsVCI was associated with an increased risk of preterm delivery in twin pregnancies irrespective of chorionicity, whereas MCI was associated with an increased preeclampsia risk, significant intertwin birthweight discordance in monochorionic pregnancies and small-for-gestational age neonates in dichorionic pregnancies.

Current practice of placental cord insertion documentation in Australia - A sonographer survey.

During pregnancy, the umbilical cord attaches to the placenta in a central, eccentric, marginal or velamentous location. Maternal and fetal complications are associated with marginal and velamentous cord insertions, the most clinically significant being perinatal mortality due to undiagnosed vasa praevia. Current literature describes a wide variation regarding regulation of placental cord insertion (PCI) documentation during antenatal ultrasound examinations. This prospective cross-sectional study aimed to assess the current practice of antenatal PCI documentation in Australia. Members of the Australian Sonographer Accreditation Registry were invited to participate in an online survey which was distributed between February and March 2022. Four hundred ninety sonographers met the inclusion criteria for the study of which 330 (67.3%) have more than 10 years' experience as a sonographer and 375 (76.5%) are employed primarily in a public or private setting offering general ultrasound. Most respondents (89.6%) indicated documentation of the PCI site is departmental protocol at the second trimester anatomy scan (17-22 weeks gestation), but PCI documentation is protocol in less than 50% of other obstetric ultrasound examinations listed in the survey. The PCI site is included in the formal ultrasound report at a rate significantly less than inclusion in the departmental protocol and the sonographer's worksheet. Considering the potential maternal and fetal complications associated with abnormal PCI and the ease at which the PCI site is identified in the first and second trimesters, we believe that standard inclusion of the PCI site in departmental protocol and in the formal ultrasound report from 11 weeks gestation, regardless of whether it is normal or abnormal, would prove invaluable.

ANTENATAL UMBILICAL CORD COILING INDEX AS A PREDICTOR OF PREGNANCY OUTCOME

Introduction: Negative pregnancy outcomes, such as stillbirth, neonatal mortality, premature delivery, low birth weight, and admission to the neonatal intensive care unit (NICU), are linked to anomalies in the umbilical cord, such as the nuchal cord, marginal cord insertion, and aberrant cord coiling. Not many studies throw insight into this topic from South Indian settings. Objective: To investigate the role of the antenatal umbilical cord coiling index (AUCCI) in predicting adverse pregnancy outcomes. Methods: This is a cross-sectional study of 200 pregnant women who underwent antenatal ultrasound scans with ≥ 28 weeks of gestation with singleton live pregnancy who attended the obstetrics department. The AUCCI was measured as the ratio of the total number of coils in the umbilical cord to its length. The primary outcome was to nd the association between AUCCI and adverse pregnancy outcomes, including both maternal and fetal outcomes. Results: The mean AUCCI was 24 ±0.10, we categorised AUCCI &lt;0.42 as hypocoiled, 0.42 – 0.59 as normocoiled and more than equal to 60 as hypercoiled based on distribution. We also observed a signicant association between AUCCI and PPH, PROM, APGAR score, NICU admission, and low birth weight. (p-value &lt;0.05) Conclusion: The antenatal umbilical cord coiling index is a simple and noninvasive tool that can be used to predict adverse pregnancy outcomes. The lower the AUCCI, the higher the risk of adverse pregnancy outcomes

Impact of marginal cord insertion on perinatal outcomes: a systematic review and meta-analysis.

Despite its high prevalence and the possible link with perinatal complications, marginal cord insertion is surrounded by considerable controversy regarding management. This meta-analysis aimed to study its association with several perinatal outcomes in a manner that provides trustworthy and exact effect measures, enabling us eventually to evaluate its overall risk for pregnancy. A systematic search was performed in Medline, Scopus, and the Cochrane Library on July 30, 2022, to identify eligible studies. Observational studies, including singleton pregnancies and comparing MCI with central cord insertion or eccentric cord insertion, either prenatally or postnatally identified, were considered eligible. The Newcastle-Ottawa Scale was used to assess study quality, and the Quality in Prognosis Studies tool was used to assess bias risk. The main outcome was small-for-gestational-age neonates. A Q test and an I2 score were used to assess study heterogeneity. The analyses were performed using a random-effects model, and the results were expressed as relative risk or mean difference with a 95% confidence interval. Overall, 15 studies (13 cohort studies and 2 case-control studies) contributed data to the analysis. There was a prenatal diagnosis in 7 studies and a postnatal diagnosis in 8 studies. The overall prevalence of marginal cord insertion was 6.15% (range, 1.13%-11.3%). Pregnancies with marginal cord insertion compared with pregnancies with central cord insertion were found to be at higher risk of small-for-gestational-age neonates (relative risk, 1.25; 95% confidence interval, 1.21-1.29), preeclampsia (relative risk, 1.61; 95% confidence interval, 1.54-1.67), placental abruption (relative risk, 1.53; 95% confidence interval, 1.34-1.75), stillbirth (relative risk, 1.97; 95% confidence interval, 1.02-3.78), preterm delivery (relative risk, 1.47; 95% confidence interval, 1.24-1.75), lower mean gestational age at birth (mean difference, -0.20; 95% confidence interval, -0.38 to -0.01), emergency cesarean delivery (relative risk, 1.39; 95% confidence interval, 1.35-1.44), lower mean birthweight (mean difference, -139.19; 95% confidence interval, -185.78 to -92.61), 5-minute Apgar score of <7 (relative risk, 1.48; 95% confidence interval, 1.00-2.19), and neonatal intensive care unit admission (relative risk, 1.57; 95% confidence interval, 1.20-2.06). When only pregnancies with prenatally diagnosed MCI were considered, the risk remained high regarding small for gestational age (relative risk, 1.34; 95% confidence interval, 1.21-1.48), preeclampsia (relative risk, 1.42; 95% confidence interval, 1.01-1.99), stillbirth (relative risk, 2.99; 95% confidence interval, 1.03-8.70), preterm delivery (relative risk, 1.41; 95% confidence interval, 1.19-1.68), lower mean gestational age at birth (mean difference, -0.22; 95% confidence interval, -0.33 to -0.11), and lower mean birthweight (mean difference, -122.41; 95% confidence interval, -166.10 to -78.73). Here, the higher risk that marginal cord insertion poses for pregnancy, regarding several adverse outcomes, became evident. Many of these associations persisted among the prenatally diagnosed pregnancies. The underlining pathophysiology should be investigated, and further research is needed on the effect of increased surveillance in improving perinatal outcomes.

Anomalous Marginal Insertion of Umbilical Cord in Placentas of COVID-19-Affected Pregnant Mothers: A Cross-Sectional Study.

Aim Study the effect of coronavirus disease-19 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), on the placenta and in turn study its effects on pregnancy and newborn outcomes. Methods In this cross-sectional study, which was conducted in the term pregnant women who underwent delivery, their placentas were collected after delivery along with the mothers' blood and cord blood. Results Among the 212 pregnant women recruited, the prevalence of marginal cord insertion (MCI) in the placentas after delivery, was found to be 23% (n=48). Among these 48 cases (n=48) with MCI, 58.33% (n=28) were COVID-19 positive. The placentas with MCI had significantly lower minimum placental circumference (probability value/p value=0.04)and significantly longer umbilical cord (p-value=0.05). COVID-19 antibodies transfer from themother to the umbilical cord (C/M antibodies ratio) was observed to be lower, albeit insignificantly. Both the weight of newborns (p value=0.03) and their COVID-19 antibodies levels (p-value=0.05) were observed to be significantly lower in the MCI group. Univariate analysis shows that a body mass index (BMI) ≥ 23 of the mothers was significantly associated with abnormal MCI. Conclusion The prevalence of MCI was observed to be high in COVID-19-affected mothers in our study. MCI was associated with lower placental size, newborn weight, lesser transfer of COVID-19 antibodies from the mother to the fetus across the umbilical cord, and lower antibody levels in the cord blood when compared to maternal blood.

PLACENTAL CHARACTERISTICS AND NEONATAL OUTCOME OF SINGLETON DELIVERIES IN A ZONAL HOSPITAL, JANAKPUR

Background: There are number of maternal and neonatal factors that determine placental characteristics which in turn determine intrauterine life of the fetus. There are limited studies regarding the topic in Nepalese context. Therefore this study aimed to assess the placental characteristics and neonatal outcome of singleton deliveries in a Zonal hospital. Methods: Cross-sectional study was carried out among 300 women with single term delivery using convenience sampling. A structured interview schedule, placental examination perfoma and APGAR score were used to collect data. Data were entered in SPSS version 20 for Windows and analyzed using descriptive and inferential statistics. Results: Findings revealed that almost all placentas were red in color (93.3%), round in shape (99.3%), centrally located umbilical cord (96.0%) and normally inserted placental membrane. Mean placental weight and umbilical length was 492.17 (±99.160) gm and 52.89 (±11.151) cm respectively. Almost all neonates had normal birth weight i.e. 2500 gm., mean weight 2936.13 gm. (± 368.33). Seventeen percent of neonate had mild to severe asphyxia in one minute. Significant association was found between placental weight and maternal factors such as educational status (p= 0.008), annual household income (p= 0.013) and parity (p= 0.001). Significant relationship was found between weight of placenta and weight of neonate (rs = 0.335, p = &lt;0.05) as well as weight of neonate and APGAR score (rs =0.145, p = &lt;0.05) Conclusions: Few deliveries have marginal cord insertion and circumvallate placenta. Some neonates have asphyxia and admitted to intensive care unit. Hence regular placental examinations provide valuable information immediate care to mother and neonates.

Abnormal umbilical cord insertion and birth weight discordancy in monochorionic diamniotic twins: A retrospective study

To investigate the relationship between abnormal umbilical cord insertion and birthweight discordance in monochorionic diamnionic (MCDA) twins. A total of 137 pairs of MCDAs were retrospectively analyzed who delivered and survived in Hangzhou Women's Hospital from January 2016 to December 2021. According to different insertion methods, they were divided into normal cord insertion group (n = 57), marginal cord insertion (MCI) group (n = 34) and velamentous cord insertion (VCI) group (n = 46). The correlation was analyzed between different insertion methods of umbilical cord and the discordant birth weight of MCDAs. The gestational age of delivery with velamentous cord insertion was significantly earlier than those with normal and marginal insertion (P < .05). There were significant differences in birthweight between large fetus (F1) and small fetus (F2) with different umbilical insertion methods (P < .05). The birthweight of F1 and F2 in normal insertion group was significantly higher than those in MCI and VCI group (P < .05). Logistic regression analysis showed that VCI was significantly associated with birth weight in F1/F2, birthweight discordance ≥ 20%, and birthweight discordance ≥ 25%, however MCI and VCI were not an independent factor for discordance in birthweight of MCDAs (P > .05). Umbilical cord insertion method can lead to inconsistency in birthweight of MCDA twins, however they were not an independent factor for discordance in birthweight.

Fetal Disseminated Malignant Rhabdoid Tumor.

Fetal Disseminated Malignant Rhabdoid Tumor.

Risk factors for placental abruption.

Our case-control study, aiming at identifying the risk factors for placental abruption (PA), looked at variables including maternal age, daily transportation means, folic acid consumption, smoking, past-history of infertility, number of antenatal visits done, presence of pre-eclampsia and umbilical cord insertion. Significant risk factors for PA were frequent transportation by motorbikes, consumption of haematinic preparation not containing folic acid, passive smoking, past-history of infertility, pre-eclampsia and marginal cord insertion. Pregnant women should be counselled about the above-mentioned risk factors.

Assisted Reproductive Technique and Abnormal Cord Insertion: A Systematic Review and Meta-Analysis.

Abnormal cord insertion (ACI) is associated with adverse obstetric outcomes; however, the relationship between ACI and assisted reproductive technology (ART) has not been examined in a meta-analysis. This study examines the association between ACI and ART, and delivery outcomes of women with ACI. A systematic review was conducted, and 16 studies (1990–2021) met the inclusion criteria. In the unadjusted pooled analysis (n = 10), ART was correlated with a higher rate of velamentous cord insertion (VCI) (odds ratio (OR) 2.14, 95% confidence interval (CI) 1.64–2.79), marginal cord insertion (n = 6; OR 1.58, 95%CI 1.26–1.99), and vasa previa (n = 1; OR 10.96, 95%CI 2.94–40.89). Nevertheless, the VCI rate was similar among the different ART types (blastocyst versus cleavage-stage transfer and frozen versus fresh embryo transfer). Regarding the cesarean delivery (CD) rate, women with VCI were more likely to have elective (n = 3; OR 1.13, 95%CI 1.04–1.22) and emergent CD (n = 5; OR 1.93, 95%CI 1.82–2.03). In conclusion, ART may be correlated with an increased prevalence of ACI. However, most studies could not exclude confounding factors; thus, further studies are warranted to characterize ART as a risk factor for ACI. In women with ACI, elective and emergent CD rates are high.

Comparison of pregnancy outcomes and placental characteristics for monochorionic diamniotic twins with and without proximate umbilical cord insertion

IntroductionThis study was developed to evaluate the relative placental characteristics and pregnancy outcomes associated with monochorionic diamniotic (MCDA) twins with and without proximate umbilical cord insertion (PCI). MethodsAll MCDA twins delivered with complete placentas for whom placental characteristics were assessed via dye injection between April 1, 2013 and April 1, 2021 were included in the present cohort study. Cases were separated into PCI and non-PCI groups, and pregnancy outcomes and placental characteristics were then compared between these groups. ResultsBirthweight discordance rates were significantly lower in the PCI group relative to the non-PCI group (7.3 ± 7.5% vs 29.9 ± 16.8%, P＜0.001), while relative to the non-PCI group, rates of artery-artery (AA), vein-vein (VV), thick AA, and thick VV anastomoses were significantly higher in the PCI group (95.5% vs 67.0%, P = 0.008, 59.1% vs 16.4, P＜0.001,90.5% vs 34.9%, P＜0.001, 54.5% vs 10.5%, P＜0.001). Significantly more anastomoses were observed in the PCI group (7 (3,11) vs 6 (3,15), P = 0.015), and they were significantly larger on average than those in the non-PCI group 12.8 (6.7,21.3) mm vs 11.9 (3.4, 24.6) mm, P = 0.009). Significantly lower placental territory discordance and UCI ratios were evident in the PCI group relative to the non-PCI group (23.5 (15.0,51.0) % vs 60.0 (2.0,80.0) %, P＜0.001, 13.3 ± 5.8% vs 56.1 ± 18.0%, P < 0.001). Marginal cord insertion rates were lower in the PCI group relative to the non-PCI group (13.6% vs 77.5%, P < 0.001). DiscussionThe placental structure of MCDA twins with PCI is distinct from that of twins without PCI, and these results suggest PCI may be indicative of the more even distribution of placental territory between MCDA fetuses.

EP444: Cases of isodicentric and isochromosome-related false negatives on SNP-based cell free DNA aneuploidy screening

Cell free DNA (cfDNA) screening has been established as routine prenatal care to assess the risk of common numerical aneuploidies (trisomy 21, 18, and 13). Clinical laboratories use a variety of methodologies for cfDNA screening, including massively parallel sequencing, fluorescent imaging of single DNA molecules, and single nucleotide polymorphism (SNP)-based platforms. All cfDNA screening has high sensitivity and high specificity, but false-positive and false-negative results still occur. False-negative cfDNA results involving trisomy 13 and trisomy 18 are rare but have significant clinical and emotional impacts on families and healthcare providers. We describe two cases of fetuses with low-risk cfDNA aneuploidy screening results from a SNP-based platform and a subsequent diagnosis of a numerical aneuploidy involving an isochromosome or isodicentric chromosome. Case one presented to maternal fetal medicine care at 30 weeks gestational age with multiple anomalies. Serum screening performed at 13 weeks was low risk for trisomy 21 (1 in 1,000) and trisomy 18 (1 in 10,000). Trisomy 13 risk was not assessed. At a 25-week ultrasound, a two-vessel cord and urinary tract dilation were identified. Follow-up ultrasound at 29 weeks identified multiple anomalies: inferior vermian hypoplasia, small cerebellum, enlarged cisterna magna, left-sided congenital diaphragmatic hernia, pleural effusion, enlarged echogenic kidneys with duplicated collecting systems, bilateral foot polydactyly, and micrognathia. The patient declined amniocentesis. SNP-based cfDNA aneuploidy screening was performed at 30 weeks, and the results returned low risk (<1 in 10,000) for trisomy 21, trisomy 13, trisomy 18, and monosomy X, with a fetal fraction of 24.2%. Fetal echocardiogram at 32 weeks identified an atrial septal defect, ventral septal defects, and minor valve abnormalities. Fetal MRI at 32 weeks identified severe microphthalmia, hypotelorism, incomplete cleft palate, postaxial polydactyly of the right hand, cerebral dysgenesis, corpus callosum hypoplasia, septum pellucidum abnormality, dysmorphic lateral ventricles, prominent extra-axial spaces, misshapen pons, and brachycephaly, and it confirmed the findings seen on prior ultrasounds. The pregnancy was delivered at 34 weeks, and the child passed away on day of life three. Postnatal karyotype results were abnormal: 46,XX,+13,der(13;13)(q10;q10). This result is consistent with an unbalanced Robertsonian translocation resulting in three copies of chromosome 13, demonstrating that isochromosome 13 was not detected by the SNP-based cfDNA aneuploidy screening. Follow-up parental karyotypes were normal, confirming that the translocation occurred de novo. Case two presented to maternal fetal medicine care at 12 weeks gestational age due to an increased nuchal translucency of 5.54 mm. SNP-based cfDNA aneuploidy screening was performed at 10 weeks, and the results returned low risk (<1 in 10,000) for trisomy 21, trisomy 13, trisomy 18, and monosomy X, with a fetal fraction of 11.4%. Chorionic villus sampling was performed at 13 weeks. CVS karyotype results were abnormal: 46,XY,idic(18)(p11.3)[5]/46,XY[15]. CVS microarray was also abnormal with a 4.9Mb deletion of 18p11.32p11.31, 3.9Mb duplication of 18p11.31p11.2, and 69Mb duplication of 18p11.2q23. This result is consistent with an isodicentric chromosome 18, likely to produce a phenotype similar to trisomy 18, and was not detected by the SNP-based cfDNA aneuploidy screening. A follow-up ultrasound at 16 weeks identified a two-vessel cord, marginal cord insertion, umbilical cord cyst, omphalocele, absent nasal bone, strawberry-shaped skull, and a unilateral choroid plexus cyst. The pregnancy ended in an uncomplicated dilation and evacuation at 16 weeks gestational age. Parental follow-up testing was not pursued. We present two cases of false-negative cfDNA aneuploidy screening results due to isochromosome 13 and isodicentric chromosome 18. It is critical that providers and patients understand that cfDNA testing is a screening test where false negative results are rare but possible. While SNP-based cfDNA is a highly effective cfDNA screening methodology, it has unique limitations for trisomies caused by isochromosomes and isodicentric chromosomes.

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.

Growth outcomes of marginal cord insertion stratified by distance from placental margin

To compare the rates of fetal growth restriction (FGR) and small for gestational age (SGA) birthweight for patients with the sonographic diagnosis of marginal cord insertion at 1.0 cm or less, versus 1.01 to 2.0 cm, between the placental margin and cord insertion.