Relationship Between Anatomic Features of the Placenta, the Type of Abnormal Placental Cord Insertion and Adverse Pregnancy Outcomes in Singleton Pregnancies: A Prospective Observational Study.

INTRODUCTION: This study aimed to evaluate the potential value of placental anatomic features and various types of normal and abnormal cord insertion types in predicting adverse maternal-fetal outcomes in singleton pregnancies. We also tried to assess the association between these outcomes and various types of placental cord insertion. METHOD: This prospective observational study was performed on singleton pregnancies. For each patient placental features including diameter, thickness, type of cord insertion, and the shortest distance between the cord insertion point and placental edge were recorded. The relationship between these factors and the development of multiple adverse pregnancy outcomes including preterm labor, intrauterine fetal death (IUFD), and the rate of neonatal intensive care unit (NICU) admissions were evaluated and reported. RESULTS: Overall 308 patients were enrolled in the study. Smoker mothers had significantly smaller placentas (P-value = .008), and those with lower diameter placentas were more likely to suffer from IUFD (P-value = .0001). Shorter placental cord insertion distances led to more episodes of preterm labor (P-value = .057). Eccentric-type placental cord insertion was significantly associated with the development of preeclampsia (P-value = .006). DISCUSSION: Abnormalities in placental diameter and cord insertion can lead to significant maternal-fetal complications including preterm labor, IUFD, and preeclampsia.

Impact of Marginal and Velamentous Cord Insertion on Uterine Artery Doppler Indices, Fetal Growth, and Preeclampsia.

OBJECTIVES: To assess the impact of marginal (MCI) or velamentous (VCI) cord insertion on uterine artery pulsatility index (UtA PI), preeclampsia (PE), and offspring's birthweight (BW). METHODS: A retrospective cohort study of singleton pregnancies, undergoing routine anomaly scan at 20+0 -23+6 gestational weeks, was conducted between 2016 and 2020. The effect of placental cord insertion on BW and UtA mean PI z-scores was assessed using the t test or analysis of variance and post-hoc tests; their association with PE was evaluated with the chi-square test. A multivariate logistic regression model was employed to assess the independent association of placental cord insertion and UtA PI z-score with PE, BW <10th, <5th centile, and intrauterine death (IUD), using specific confounders. RESULTS: The study population included 4453 pregnancies. Conception via assisted reproductive technology (ART) was associated with increased risk of abnormal cord insertion (odds ratio [OR]: 2.237; 95% confidence interval [CI]: 1.561-3.206; P < .001). Women with MCI/VCI had higher mean UtA PI z-score than those with central/eccentric (0.29 vs 0.01; mean difference: -0.28; 95% CI: -0.399 to -0.165; P < .001). MCI/VCI were associated with higher rates of BW <10th centile (central/eccentric: 16.2% vs MCI: 21.9% vs VCI: 35.7%; P < .001) and BW <5th centile (9.8 vs 15.1 vs 23.2%, respectively; P < .001). No association was identified between MCI/VCI and PE (P = .968). Finally, VCI (aOR: 13.717; 95% CI: 1.576-119.379; P = .018) and increased BMI (aOR: 1.167; 95% CI: 1.071-1.271; P < .001) significantly correlated with IUD. CONCLUSIONS: Abnormal cord insertion is more common in ART pregnancies. MCI/VCI are associated with higher mean UtA PI and lower BW centile, but not with increased risk of PE.

Large Subchorionic Cyst Located at Umbilical Cord Insertion with Vascular Displacing and Intracystic Hemorrhage/Hematoma: A Case Report.

Background: Large subchorionic cysts usually arise close to the placental cord insertion site (PCIS) inducing traction on the umbilical cord, impairing blood flow and favoring fetal growth restriction (FGR). Intracystic hemorrhage/hematoma is likely due to the prothrombotic properties of X cells secretion (extravillous trophoblast), which line the cyst wall. Case report: We describe a large subchorionic cyst located exactly at the PCIS, displacing the umbilical cord vessel branches running along the cyst surface. The fetus presented with FGR. At 36 weeks of gestational age, the cyst measured 7.7 cm in maximum dimension showing a partially organized hemorrhage and a peripheral laminated thrombohematoma. The patient underwent elective cesarean section as the cyst and its vessels were at high risk of rupture during labor. Conclusion: Recognition of large subchorionic cysts close to or at the PCIS in a growth restricted fetus with subsequent expedited delivery may avoid a fatal event.

Second-Trimester Ultrasound-Measured Umbilical Cord Insertion-to-Placental Edge Distance: Determining an Outcome-Based Threshold for Identifying Marginal Cord Insertions.

OBJECTIVES: We sought to study potential diagnostic criteria for marginal placental cord insertions as determined by associations with obstetric outcomes. METHODS: This single-center retrospective cohort investigation included singleton gestations delivering from January 1, 2012, to December 31, 2016, and having a standard or detailed fetal ultrasound examination from 18 weeks to 21 weeks 6 days. Cord insertion-to-placental edge distances were used to create a referent comparison group and 3 patient groups: greater than 3.0 cm (comparison); greater than 2.0 to 3.0 cm (group 1); greater than 1.0 to 2.0 cm (group 2); and 1.0 cm or less (group 3). The primary outcome consisted of any one of spontaneous delivery before 37 weeks, fetal growth restriction, oligohydramnios, placental abruption, or intrauterine fetal demise. RESULTS: The numbers of participants and mean distances ± SDs for the comparison group and groups 1 to 3, respectively, were 628 and 4.68 ± 1.17 cm, 106 and 2.52 ± 0.26 cm, 131 and 1.60 ± 0.29 cm, and 77 and 0.36 ± 0.37 cm, respectively. The primary outcome was significantly associated only with cord insertion-to-placental edge distances of 1.0 cm or less (adjusted odds ratio, 3.05; 95% confidence interval, 1.73-5.38). CONCLUSIONS: Marginal cord insertions may be diagnosed when the cord insertion-to-placental edge distance is 1.0 cm or less.

Perinatal Outcomes Associated With Isolated Velamentous Cord Insertion in Singleton and Twin Pregnancies.

OBJECTIVES: To evaluate perinatal outcomes in singleton and twin pregnancies with pathologically confirmed velamentous cord insertion without vasa previa. METHODS: This retrospective case-control study included all nonanomalous singleton and twin pregnancies with pathologically confirmed velamentous cord insertion delivered in a single institution between January 1, 2005, and July 1, 2015, and having an ultrasound examination by maternal-fetal medicine. For each case, the next 2 consecutive deliveries matched for gestational age at delivery ± 1 week and, in twins, amnionicity and chorionicity served as controls. Primary outcomes included surgical delivery for a nonreassuring intrapartum fetal heart rate tracing, umbilical arterial cord pH of less than 7.2, 5-minute Apgar score of less than 7, birth weight below the 10th percentile, neonatal intensive care unit admission, fetal or neonatal death, and cord avulsion necessitating manual placental extraction. RESULTS: Outcomes were available for 53 singletons with 103 matched controls and 33 twin pregnancies with 65 matched controls. In singletons, velamentous cord insertion was associated with cord pH of less than 7.2 (odds ratio [OR] 3.5; 95% confidence interval [CI], 1.1-11.2; P = .039), 5-minute Apgar score of less than 7 (OR, 5.3; 95% CI, 0.99-28.1; P = .045), and cord avulsion requiring manual placental extraction (7.5% versus 0%; P = .012). Associations were suggested with increased surgical delivery for a nonreassuring intrapartum fetal heart rate tracing (OR, 2.4; 95% CI, 0.9-6.9; P = .14), birth weight below the 10th percentile (OR, 2.1; 95% CI, 0.8-5.9; P = .21), and fetal or neonatal death (3.8% versus 0%; P = .11). Velamentous cord insertions were also associated with placental abruption in singletons (7.5% versus 0%; P = .013). Among twins, velamentous cord insertion was associated with fetal or neonatal death (9.1% versus 0%; P = .036). CONCLUSIONS: Isolated confirmed velamentous cord insertion is associated with adverse perinatal outcomes in singleton and twin gestations.

Association of congenital uterine anomaly with abnormal placental cord insertion and adverse pregnancy complications: a retrospective cohort study.

OBJECTIVE: Congenital uterine anomalies during pregnancy increase the risk of pregnancy complications such as miscarriage, preterm delivery, fetal malpresentation, cesarean delivery, and fetal growth restriction. However, few studies have examined uterine anomalies in relation to perinatal complications other than those mentioned above. We investigated the association between pregnancies complicated by congenital uterine anomalies and various perinatal outcomes at our institution. METHODS: This retrospective cohort study was conducted from January 2009 to May 2021. We included cases of uterine anomalies, such as septate, bicornuate, unicornuate, and didelphic uterus. First, the perinatal complications and neonatal outcomes were compared between pregnancies complicated by uterine anomalies and those with normal uteri. Second, we conducted an analysis based on the type of uterine anomalies classified into two groups: the minor anomaly group consisted of anomalies limited to the uterine cavity, such as the septate uterus, whereas the major anomaly group included anomalies affecting the uterine shape, such as bicornuate, unicornuate, and didelphic uterus. We compared the incidence of perinatal complications among the major anomaly, minor anomaly, and normal uterus groups. RESULTS: During the study period, 45 pregnancies were complicated with uterine anomalies. The minor anomaly group included 11 patients and the major anomaly group included 34 patients. The incidence of fetal malpresentation was significantly higher in the uterine anomaly group than in the normal uterus group (18% vs. 3.7%, p = .04). Furthermore, the frequency of abnormal placental cord insertion was significantly higher in the uterine anomaly group (16% vs. 3.7%, p = .01). Examination based on the type of uterine anomaly revealed significant differences in cervical incompetence, malpresentation, cesarean section, and abnormal placental cord insertion. Cervical incompetence was more likely in patients with minor anomalies. In contrast, fetal malpresentation, cesarean section, and abnormal placental cord insertion were more likely in the major anomaly group. CONCLUSIONS: In addition to the findings reported in previous studies, abnormal placental cord insertion was more frequent in pregnancies complicated by uterine anomalies.

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

Introduction: 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. Methods: Members of the Australian Sonographer Accreditation Registry were invited to participate in an online survey which was distributed between February and March 2022. Results: 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. Conclusions: 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.

Marginal placental cord insertion: the need for follow up?

OBJECTIVE: The objectives of this study were (1) to estimate the association between marginal placental cord insertion (PCI) and small for gestational age (SGA) and other adverse perinatal outcomes and (2) to determine if pregnancy-associated plasma protein A (PAPP-A) levels was altered in these patients. METHODS: It was a retrospective cohort study of singleton pregnancies undergoing ultrasound between 2016 and 2018. Marginal PCI was defined as a distance of ≤2 cm from placental edge to PCI site, visualized in both sagittal and transverse planes, and diagnosed between 16 and 32 weeks. Velamentous PCI were excluded. The primary outcome was SGA, defined as birthweight below 10th percentile for gestational age. Pregnancies with marginal PCI were compared to those with normal PCI with respect to maternal characteristics, PAPP-A levels and adverse perinatal and delivery outcomes. RESULTS: The incidence of marginal PCI was 4.2% (76/1819). Compared to those with a normal PCI, patients with a marginal PCI were more likely to be nulliparous and less likely to be African American or morbidly obese (p < .05). SGA rate was similar between the groups (17.6% vs. 18.1%). There was a trend toward an increased incidence of oligohydramnios, polyhydramnios and breech presentation in patients with marginal PCI; however, these did not reach statistical significance. The incidence of low PAPP-A level was comparable between the groups (18.4% vs. 14.3%, p > .05). CONCLUSION: Our study did not demonstrate any increase in adverse pregnancy outcomes in the presence of marginal PCI. These findings may provide reassurance for counseling patients with this sonographic finding.

Abnormal placental cord insertion, hypertensive disorders of pregnancy and birth length may be involved in development of hypospadias in male fetuses.

OBJECTIVES: Hypospadias is a congenital disease characterized by morphological abnormalities of the penis, including abnormal urethral opening and penile flexion, which cause urination disorders and/or sexual intercourse difficulty. Various factors have been suggested to cause this anomaly, but evidence concerning risk factors causing this anomaly is insufficient. We evaluated the etiology of hypospadias in Japan using the Common Database of the National Hospitals' Neonatal study group. STUDY DESIGN: We retrospectively evaluated 7,865 male neonates registered in the NICU Common Database of the National Hospitals' Neonatal study group. The subjects were divided into two groups by the presence (n = 43) or absence (n = 7,822) of hypospadias. Statistical analyses were performed to compare nominal variables between the groups by Fisher's direct establishment calculation method and logistic regression analyses. RESULTS: A univariate analysis showed significant between-group differences in hypertensive disorders in pregnancy (odds ratio [OR]: 4.02, 95% confidence interval [CI]: 1.95-7.90), placental weight <-1.28 standard deviation (SD; OR: 5.06, 95% CI: 2.45-10.32), abnormal placental cord insertion (OR: 4.7, 95% CI: 2.62-9.76), birth length <-2SD (OR: 10.56, 95% CI: 5.00-21.1) and birth weight <-2SD (OR: 8.17, 95% CI: 4.17-15.68). A multivariate analysis showed a significant between-group difference in hypertensive disorders of pregnancy (adjusted OR [AOR]: 2.30, 95% CI: 1.09-4.85), abnormal placental cord insertion (AOR: 3.69, 95% CI: 1.83-7.44) and birth length <-2SD (AOR: 3.44, 95% CI: 1.26-9.42). CONCLUSION: Abnormal placental cord insertion, hypertensive disorders of pregnancy and birth length may be involved in hypospadias development in male neonates in conjunction with placental dysfunction in early pregnancy.

Placental cord insertion distance from the placental margin and its association with adverse perinatal outcomes.

OBJECTIVE: The placental cord insertion (PCI) to the placental margin has not been well studied as a continuous variable in relation to birth outcomes. We sought to evaluate the impact of PCI distance on outcomes associated with placental function and development of fetal growth restriction (FGR). STUDY DESIGN: This was a retrospective study of singleton gestations that underwent a fetal anatomy ultrasound from 2011-2013. The PCI was recorded as the distance in centimeters from the placental margin. Patients had FGR if the overall estimated fetal weight was <10 % for gestational age or abdominal circumference <5 % in the third trimester. Delivery, obstetric, and neonatal outcomes were obtained via medical chart review. Logistic and linear regression models were used to assess the impact of PCI distance on maternal and neonatal delivery outcomes. RESULTS: Of the 1443 women who met inclusion criteria, 93.6 % delivered at term. The mean (±SD) PCI distance was 4.4 ± 1.4 cm. There was no association between PCI and cesarean delivery, peripartum hemorrhage (PPH), pre-eclampsia, 5-min Apgar, or intrauterine fetal demise. PCI distance was statistically significantly shorter in patients requiring neonatal intensive care unit (NICU) admission (4.1 ± 1.5 cm vs. 4.4 ± 1.4 cm, p = 0.02) and was associated with lower birthweight (p = 0.01), though this association was no longer seen when corrected for gestational age. There were 3.5 % of patients who developed FGR; PCI distances from the placental edge were not significantly different for patients who developed FGR compared to those who did not (4.2 ± 1.4 cm vs. 4.5 ± 1.4 cm, p = 0.18). Furthermore, a receiver operating characteristic (ROC) curve for PCI had poor sensitivity (area under the curve [AUC] 0.57, 95 % CI 0.49-0.65). CONCLUSION: PCI distance at the time of fetal anatomic survey is significantly associated with NICU admission, though does not appear to impact rates of preterm birth, pre-eclampsia, PPH or cesarean delivery. PCI distance in singleton gestations does not appear to be predictive of FGR.

Velamentous cord insertion: results from a rapid review of incidence, risk factors, adverse outcomes and screening.

BACKGROUND: Velamentous cord insertion (VCI) is an umbilical cord attachment to the membranes surrounding the placenta instead of the central mass. VCI is strongly associated with vasa praevia (VP), where umbilical vessels lie in close proximity to the internal cervical os. VP leaves the vessels vulnerable to rupture, which can lead to fatal fetal exsanguination. Screening for VP using second-trimester transabdominal sonography (TAS) to detect VCI has been proposed. We conducted a rapid review investigating the quality, quantity and direction of evidence available on the epidemiology, screening test accuracy and post-screening management pathways for VCI. METHODS: MEDLINE, Embase and the Cochrane Library were searched on 5 July 2016 and again on 11 October 2019, using general search terms for VP and VCI. Only peer-reviewed articles reporting on the epidemiology of VCI, the accuracy of the screening test and/or downstream management pathways for VCI pregnancies were included. Quality and risk of bias of each included study were assessed using pre-specified tools. RESULTS: Forty-one relevant publications were identified; all but one were based on non-UK pregnancy cohorts, and most included relatively few VCI cases. The estimated incidence of VCI was 0.4-11% in singleton pregnancies, with higher incidence in twin pregnancies (1.6-40%). VCI incidence was also increased among pregnancies with one or more other risk factors, including in vitro fertilisation pregnancies or nulliparity. VCI incidence among women without any known risk factors was unclear. VCI was associated with adverse perinatal outcomes, most notably pre-term birth and emergency caesarean section in singleton pregnancies, and perinatal mortality in twins; however, associations varied across studies and the increased risk was typically low or moderate compared with pregnancies without VCI. In studies on limited numbers of cases, screening for VCI using TAS had good overall accuracy, driven by high specificity. No studies on post-screening management of VCI were identified. CONCLUSIONS: Literature on VCI epidemiology and outcomes is limited and low-quality. The accuracy of second-trimester TAS and the benefits and harms of screening cannot be determined without prospective studies in large cohorts. Modelling studies may indicate the feasibility and value of studying the epidemiology of VCI and the potential impact of detecting VCI as part of a population screening programme for VP.

Accuracy of fetal anatomy survey in the diagnosis of velamentous cord insertion: a case-control study.

OBJECTIVE: Our objective was to determine the accuracy of ultrasound at the time of the fetal anatomy survey in the diagnosis of velamentous cord insertion (VCI). STUDY DESIGN: This retrospective case-control study identified placentas with VCI (cases) and randomly selected placentas with normal placental cord insertion (PCI) (controls) as documented by placental pathology for mothers delivered from 2002 through 2015. Archived ultrasound images for PCI at the time of the fetal anatomy survey were reviewed. Data analysis was by calculation of sensitivity, specificity, and accuracy and their 95% CI for the ultrasound diagnosis of VCI. RESULTS: The prevalence of VCI was 1.6% of placentas submitted for pathologic examination. There were 122 cases of VCI and 347 controls with normal PCI. The performance criteria calculated for the diagnosis of VCI at the time of fetal anatomy survey were as follows: sensitivity 33.6%; 95% CI: 25.3, 42.7; specificity 99.7%; 95% CI: 98.4, 99.9 and accuracy 82.5; 95% CI: 80.5, 82.9. CONCLUSION: The identification of a VCI at the time of fetal anatomy survey is highly specific for the presence of a VCI as documented by placental pathology. The sensitivity in this study was less than expected. Sensitivity could be improved by reducing the number of nonvisualized PCIs, creating an awareness of risk factors for VCI, and obtaining more detailed images in the case of an apparent marginal PCI.

Abnormal placental cord insertion and adverse pregnancy outcomes: a systematic review and meta-analysis.

BACKGROUND: Abnormal placental cord insertion (PCI) includes marginal cord insertion (MCI) and velamentous cord insertion (VCI). VCI has been shown to be associated with adverse pregnancy outcomes. This systematic review and meta-analysis aims to determine the association of abnormal PCI and adverse pregnancy outcomes. METHODS: Embase, Medline, CINAHL, Scopus, Web of Science, ClinicalTrials.gov, and Cochrane Databases were searched in December 2016 (from inception to December 2016). The reference lists of eligible studies were scrutinized to identify further studies. Potentially eligible studies were reviewed by two authors independently using the following inclusion criteria: singleton pregnancies, velamentous cord insertion, marginal cord insertion, and pregnancy outcomes. Case reports and series were excluded. The methodological quality of the included studies was assessed using the Newcastle-Ottawa Scale. Outcomes for meta-analysis were dichotomous and results are presented as summary risk ratios with 95% confidence intervals. RESULTS: Seventeen studies were included in the systematic review, all of which were assessed as good quality. Normal PCI and MCI were grouped together as non-VCI and compared with VCI in seven studies. Four studies compared MCI, VCI, and normal PCI separately. Two other studies compared MCI with normal PCI, and VCI was excluded from their analysis. Studies in this systematic review reported an association between abnormal PCI, defined differently across studies, with preterm birth, small for gestational age (SGA), low birthweight (< 2500 g), emergency cesarean delivery, and intrauterine fetal death. Four cohort studies comparing MCI, VCI, and normal PCI separately were included in a meta-analysis resulting in a statistically significant increased risk of emergency cesarean delivery for VCI (pooled RR 2.86, 95% CI 1.56-5.22, P = 0.0006) and abnormal PCI (pooled RR 1.77, 95% CI 1.33-2.36, P < 0.0001) compared to normal PCI. CONCLUSIONS: The available evidence suggests an association between abnormal PCI and emergency cesarean delivery. However, the number of studies with comparable definitions of abnormal PCI was small, limiting the analysis of other adverse pregnancy outcomes, and further research is required.

Ultrasonographic evaluation of placental cord insertion at different gestational ages in low-risk singleton pregnancies: a predictive algorithm.

OBJECTIVE: To evaluate the accuracy of ultrasound in visualizing placental cord insertion (PCI) at different gestational ages in order to recommend the most feasible period during pregnancy to identify it. Secondary aim was to propose a predictive algorithm for PCI visualization. METHODS: We performed a single-center, prospective cohort study. We enrolled patients with singleton low-risk pregnancies who underwent fetal ultrasound scan at different gestational ages. We excluded patients with body mass index of 30 Kg/m2 or more, uterine fibroids larger than 5 cm, high-risk pregnancies, fetal weight lower than < 10° percentile or higher than > 90° percentile, increased ("deep pocket" > 80 mm) or decreased ("deep pocket" < 20 mm) amniotic fluid. RESULTS: Among the 468 recruited patients, the visualization of PCI was not possible in 5.77% of the cases. Furthermore, we showed that PCI visualization was lower as the gestational age increased (p = 0.049) and more difficult in case of posterior placenta (p = 0.001). CONCLUSIONS: PCI should be evaluated in the first trimester or as early as possible during the second trimester. Moreover, we propose a feasible model to predict the possibility of PCI visualization according to gestational age and uterine site of implantation.