Umbilical Cord Insertion Site Research Articles

Morphological Variations of the Umbilical Cord of Full-term Fetuses – Correlation with Maternal and Newborn Parameters

Introduction: Abnormalities in the development and site of insertion of the umbilical cord (UC) can cause problems which have the potential to affect maternal and fetal health. The aim of the present study was to evaluate the gross features of UC of singleton pregnancies and correlate it to the newborn parameters and maternal parameters at term. Materials and Methods: An observational, descriptive pilot study was carried out with 100 placentas. All ethical principles for human research were followed and ethical approval was obtained from the institutional ethics committee of the medical college from where data were collected. The inclusion criteria were the adequately preserved placenta with no gross abnormalities. Placenta belonging to hypertensive mothers and mothers with gestational diabetes were excluded. Results and Conclusion: The UC morphology was recorded and analyzed. Newborn parameters and maternal parameters were correlated to UC parameters. The present study statistics showed 53% placentas with central insertion, 36% eccentric insertion, 3% furcated and marginal insertions each, and 5% specimens with velamentous insertion. A correlation between the UC insertion site and birth weight was observed. Low birth weight was observed when the cord was inserted eccentrically. Further investigations are required among velamentous insertion to reach a conclusion for maternal blood group correlations.

Morphological Variations of the Umbilical Cord of Full-term Fetuses – Correlation with Maternal and Newborn Parameters

Introduction: Abnormalities in the development and site of insertion of the umbilical cord (UC) can cause problems which have the potential to affect maternal and fetal health. The aim of the present study was to evaluate the gross features of UC of singleton pregnancies and correlate it to the newborn parameters and maternal parameters at term. Materials and Methods: An observational, descriptive pilot study was carried out with 100 placentas. All ethical principles for human research were followed and ethical approval was obtained from the institutional ethics committee of the medical college from where data were collected. The inclusion criteria were the adequately preserved placenta with no gross abnormalities. Placenta belonging to hypertensive mothers and mothers with gestational diabetes were excluded. Results and Conclusion: The UC morphology was recorded and analyzed. Newborn parameters and maternal parameters were correlated to UC parameters. The present study statistics showed 53% placentas with central insertion, 36% eccentric insertion, 3% furcated and marginal insertions each, and 5% specimens with velamentous insertion. A correlation between the UC insertion site and birth weight was observed. Low birth weight was observed when the cord was inserted eccentrically. Further investigations are required among velamentous insertion to reach a conclusion for maternal blood group correlations.

Prevalence, Risk Factors, and Perinatal Outcomes of Velamentous Umbilical Cord Insertion in Twin Pregnancies: A Single-Center Retrospective Study.

The effect of velamentous cord insertion (VCI) on perinatal outcomes in twin pregnancies is unclear due to conflicting findings. This retrospective study aimed to examine VCI prevalence and related risk factors in twin pregnancies and its association with adverse perinatal outcomes. Women with twin pregnancies who delivered between January 2012 and December 2021 in a single tertiary hospital were included. The participants were divided into dichorionic (DC) and monochorionic diamniotic (MCDA) groups, and their maternal and fetal characteristics and VCI rates were compared. Logistic regression models were used to identify risk factors for VCI and VCI-related perinatal outcomes. Among the 694 twin pregnancies included in this study, the VCI rate was significantly higher in MCDA than in DC twins. Body mass index and MCDA twins were significant risk factors for VCI, whereas assisted reproductive technology pregnancy was a significant protective factor against VCI. In DC twins, VCI did not affect perinatal outcomes. In MCDA twins, VCI was a significant risk factor for fetal growth restriction, twin-to-twin transfusion syndrome, and preterm birth at <36 weeks. VCI was a prominent risk factor for adverse perinatal outcomes only in MCDA twins. Antenatal sonographic assessment of the umbilical cord insertion site would be beneficial.

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.

Peripheral cord insertion is associated with adverse pregnancy outcome only when accompanied by clinically significant placental pathology.

To examine the relationship between umbilical cord insertion site, placental pathology and adverse pregnancy outcome in a cohort of normal and complicated pregnancies. Sonographic measurement of the cord insertion and detailed placental pathology were performed in 309 participants. Associations between cord insertion site, placental pathology and adverse pregnancy outcome (pre-eclampsia, preterm birth, small-for-gestational age) were examined. A total of 93 (30%) participants were identified by pathological examination to have a peripheral cord insertion site. Only 41 of the 93 (44%) peripheral cords were detected by prenatal ultrasound. Peripherally inserted cords were associated significantly (P < 0.0001) with diagnostic placental pathology (most commonly with maternal vascular malperfusion (MVM)); of which 85% had an adverse pregnancy outcome. In cases of isolated peripheral cords, without placental pathology, the incidence of adverse outcome was not statistically different when compared to those with central cord insertion and no placental pathology (31% vs 18%; P = 0.3). A peripheral cord with an abnormal umbilical artery (UA) pulsatility index (PI) corresponded to an adverse outcome in 96% of cases compared to 29% when the UA-PI was normal. This study demonstrates that peripheral cord insertion is often part of the spectrum of findings of MVM disease and is associated with adverse pregnancy outcome. However, adverse outcome was uncommon when there was an isolated peripheral cord insertion and no placental pathology. Therefore, additional sonographic and biochemical features of MVM should be sought when a peripheral cord is observed. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Voluminous chorionic cyst of the umbilical cord insertion site: a case report

Voluminous chorionic cyst of the umbilical cord insertion site: a case report

Combined negative pressure wound therapy with irrigation and dwell time and artificial dermis prevents infection and promotes granulation formation in a ruptured giant omphalocele: a case report

BackgroundOmphalocele is a congenital abdominal wall defect of the umbilical cord insertion site. A giant omphalocele, with a fascial defect > 5 cm in diameter and/or containing > 50% of the liver within the hernia sac, can be challenging for pediatric surgeons. Recently, negative pressure wound therapy has been reported as an effective management for giant omphaloceles; however, it is not recommended for an infected wound with necrotic tissue as it may exacerbate infection. We adopted negative pressure wound therapy with irrigation and dwell time (NPWTi-d) for a case of a ruptured giant omphalocele. Artificial membranes, followed by artificial dermis, were used to promote fibrous capsule formation, and then NPWTi-d was used to promote granulation while controlling infection. However, studies have not been conducted regarding NPWTi-d for ruptured giant omphaloceles; hence, we present our treatment experience with NPWTi-d for a giant omphalocele.Case presentationThe patient was a boy born at 38 weeks and 3 days of gestation, weighing 1896 g. He was diagnosed with a ruptured giant omphalocele with a total liver and intestine defect hole of 10 cm × 10 cm. The patient underwent silo placement using an artificial mesh, followed by plicating the artificial mesh at 4 days of age. The herniated viscera were gradually reduced into the abdominal cavity; however, the defect size was still large. Hence, a collagen-based artificial dermis was patched on the defect hole. After creating a fresh and smooth granulated tissue, NPWTi-d was applied at 33 days of age to promote granulation and control infection. We used the 3 M™ V.A.C.® Ulta Therapy Unit with 3 M™ VeraFlo™ therapy. NPWTi-d was stopped at 60 days of age when the granulation tissue was well formed including at the artificial dermis site. The wound was managed with prostandin ointment and appropriate debridement, resulting in complete epithelialization at 5 months of age.ConclusionsArtificial membranes followed by artificial dermis were used to promote a fibrous capsule and artificial dermis granulation, which protects against organ damage. NPWTi-d achieved better control of infection and promoted wound healing. NPWTi-d combined with artificial dermis can effectively treat ruptured giant omphaloceles.

Two Giant Placental Chorangiomas Discovered at 34 week’s Gestation: A Case Report

Abstract Introduction/Objective Chorangioma is a benign vascular tumor of the placenta, likely hamartoma, occurring in 1% of all examined placentas and arising from the primitive chorionic mesenchyme. The clinical significance is related to the size of the tumor. Most chorangiomas are small and asymptomatic; however, those larger than 4 cm are associated with intrauterine growth restriction (IUGR), polyhydramnios, preterm delivery, arteriovenous shunting, hydrops, and fetal thrombocytopenia. Methods/Case Report Herein, we present a case report of a placenta with two chorangiomas that are prenatally detected in a 25-year-old G2P1 female patient by ultrasound which showed a placental mass and mild polyhydramnios. The patient also developed hypertension and preeclampsia so she was referred for early induction of labor. The patient was elected for caesarian section and the placenta was delivered at 35 weeks of gestation. Grossly, two tan soft well-circumscribed lobulated placental masses were identified and measured 9.5 x 9.1 x 3.3 cm and 5.5 x 4.5 x 1.9 cm, respectively. The two masses were joined together by a thick blood vessel. The larger 9.5 cm mass was connected to the placental disc at the umbilical cord insertion site and is associated with blood vessel thrombosis. Microscopically the mass showed proliferation of capillary-sized vessels with surrounding stroma consistent with chorangioma. Clinical, radiological, and microscopic profiles support the diagnosis of placental chorangioma. Results (if a Case Study enter NA) N/A Conclusion To our knowledge, this is the first case report of two giant placental chorangiomas connected together by a thick blood vessel. Although both are giant (more than 4 cm), early diagnosis and timely intervention led to good maternal and neonatal outcomes aided with neonatal intensive care unit management.

Association of placental morphology and fetal birth weight

Background: The placenta plays a crucial role in sustaining pregnancy and supporting healthy foetal growth and function. Placental morphology predicts illness patterns in adults and foetal development. Birth weight is a significant predictor of a child's survival, healthy development, and growth. The connection between birth weight and perinatal outcome has long been understood in obstetrics. As is generally known, low birth weight is a known risk factor for the child's long-term health. The aim of the study was to find any association between birth weight, gender and placental morphology. Methods: An analytical cross sectional study was conducted in the anatomy department of Anatomy, Bhaarath Medical college and Hospital, Chennai. Placentae of 200 were collected. Morphological analysis including placental weight, number of cotyledons, site of umbilical cord insertion and fetal and maternal surface area, were measured in normal and low birth weight babies. Results: Birth weight showed a positive connection with gestational age. Birth weight and greater values in men were positively and significantly correlated with placental parameters (p 0.001). Regression models employing the newborn's sex and placental morphometry were used to estimate the birth weight; weight (R2=0.461), surface area (R2=0.411), and volume (R2=0.456) were calculated.

Effect of acoustic output on fetal ultrasound color Doppler performance

Increasing transmit acoustic output in color Doppler ultrasound imaging improves the received data temporal signal-to-noise ratio (SNR), but such elevated acoustic pressures increase the potential for inertial cavitation and tissue heating. Safety regulations constrain maximum acoustic output to mitigate bioeffects, but lower output is encouraged following the ALARA (As Low As Reasonably Achievable) principle. In this study, color Doppler imaging with a Siemens ACUSON Sequoia and 10L4 transducer was performed on the placenta umbilical cord insertion site of 10 pregnant volunteers. Flow data were collected at five acoustic output levels and four frequency settings to assess each parameter’s effect. The output Thermal Index (TI) ranged from 0.001 to 0.7 and frequency ranged from 4.0 to 7.3 MHz. Increased temporal SNR in the receive signals at high output levels was linked to lower pulse-to-pulse phase variance and velocity bias. These metrics changed most dramatically across low output levels, before converging towards constant phase variance and velocity bias at high temporal SNR. The output levels approaching stable phase variance and velocity were specific to each volunteer and frequency. This result provides a framework for future automated Doppler ALARA implementations that calculate performance metrics and adjust acoustic power in accordance with ALARA principles.

Assessment of placental abruption with diffusion-weighted imaging.

To investigate whether placental abruption without fetal distress could be assessed by apparent diffusion coefficient (ADC) values in magnetic resonance imaging (MRI). We conducted a retrospective case-control study at a single center. ADC values at the lesions of placental abruption in the abruption group (n=8) were compared to those in the control group (n=32). In the abruption group, ADC values at the sites of abruption were also compared to those at the nonabruption sites within the same placenta. The ADC values in the placental area above the abruption site in the abruption group showed lower values than those in the control group when the slice containing the umbilical cord insertion site was set as the reference, and those values were compared in each corresponding slice. Compared with average ADC values, those above the abruption site in the abruption group were also significantly lower than those in the control group (p < 0.001). Furthermore, ADC values at the area above abruption were lower than those at the nonabruption area of all planes in the abruption group. ADC values at the lesions above the placental abruption site were reduced compared to those in the normal placenta and those in the nonabruption area. Thus, it would be helpful to understand the pathophysiology of placental abruption in expectant management, although further investigations would be needed.

ASSOCIATION BETWEEN PLACENTAL MORPHOMETRIC PARAMETERS AND BIRTH WEIGHT IN DICHORIONIC DIAMNIOTIC TWINS

The aim: To assess morphometric parameters of placentas and to evaluate the correlation between the placental disk shape, the site of the umbilical cord insertion and the birth weight of dichorionic twins. Materials and methods: The geometry of placentas, distances between umbilical cord insertion sites and the centroids of the disks were measured in 135 pairs of dichorionic diamniotic twins. The impact of the above-mentioned parameters on the birth weight and placental mass was analyzed. Results: In terms of weight and geometric parameters of placentas, no proven discrepancy between different types of twins and inside pairs was found. A strong correlation was established between the placental weight and birth weight (r = 0.71, p &lt; 0.05). Both the placental weight and birth weight showed the strong correlation with S*Circ (r = 0.62, p &lt; 0.05). The displacement of the umbilical cord insertion site from the centroid of the placenta was negatively correlated with its mass (r = -0.428, p &lt; 0.0001) and birth weight (r = -0.6115, p &lt; 0.0001). The displacement along the maximum axis proved to play a significant role. Conclusions: In dichorionic diamniotic twins, the area of the placentas plays the determining role in the functional activity of the organ, which increases when its shape approaches the circle. The area of the placenta multiplied by its circularity had the strongest correlation with birth weight and placental mass. The farther from the centre the umbilical cord is inserted, the lower the functional capacity of the placenta is.

THE RELATIONSHIP BETWEEN PLACENTAL GROWTH RATES AND THE BIRTH WEIGHT IN DICHORIONIC DIAMNIOTIC TWINS

Relevance. Birth weight is one of the main indicators of intrauterine fetal development. The condition of the placenta reflects the influence of the maternal environment on the fetus. It is important to find out which placental growth parameters significantly affect the mass of dichorionic diamniotic (DHDA) twins.&#x0D; Objective: to investigate the relationship between indicators of placental growth and birth weight of dichorionic diamniotic twins.&#x0D; Materials and methods. One hundred thirty-five DCDA twin pairs were studied during 2016-2020: 68 pairs were opposite-sex, 32 – same-sex females and 35 – same-sex males. The gestational age ranged from 29 to 39.5 weeks, averaging 36,4 ± V1,74 weeks. The influence of such parameters as maximum and minimum placental diameters, as well as perimeter, area, circularity (Circ), roundness, thickness, mass (PM), volume (V), displacement of the umbilical cord insertion site from the placental disc centre along its maximum (XCD) and the minimum axis (YCD).&#x0D; Results. A strong positive correlation was found between PM and birth weight in the whole cohort of DCDA twins (r = 0.7059, p &lt; 0.0001). It was strongest in the same-sex female group (r = 0.7886, p &lt; 0.0001), then in the opposite-sex pairs (r = 0.7093, p &lt; 0.0001), slightly weaker – in the same-sex male couples (r = 0.6065, p &lt; 0.0001). The birth weight and PM correlated with almost all indicators that characterize the placental shape. The strongest correlation was with V (rV_BW = 0.66, p &lt; 0.0001; rV_PM = 0.59, p &lt; 0.0001) and the area*Circ (rS*Circ_BW = 0.64; p &lt; 0.0001; rS*Circ_PM = 0.62; p &lt; 0.0001). The multiple regression analysis of the effect of different morphometric parameters of the placentas on the birth weight has demonstrated the statistical significance of the following parameters: XCD, PM, V, YCD and Circ. The general regression model for the whole DCDA group: birth weight = 2242,3 + 0,8*МП + V – 10,0* XCD (R2 = 0,7002). Similar equations were calculated for different types of DCDA tweens. Thus, morphometric measures account for the 67-85% variances of the birth weight of the DCDA tweens.&#x0D; Conclusion. In the DCDA pairs, placental mass strongly positively correlated with birth weight. Both indicators are in strong relationship with V and their area*Circ. The closer the placental shape is to the circle, the higher its functional ability. Deterioration of the latter may be due to the far fixation of the umbilical cord from the center of the placental disc. The displacement along the maximum axis has a stronger impact comparing to the displacement relative to the minimum axis. The multiple regression analysis has revealed that statistical significance had XCD and PM or V in the whole types of twins. Proposed models demonstrate that 67-85% of the variability of birth weight may be accounted for by the three or four simple placental measures

Influence of the placental cord insertion site on the placental mass and the birth weight in dichorionic diamniotic twins

The aim of the study was to determine the effect of the displacement of the umbilical cord insertion site from the centre of the placenta on the placental mass and the birth weight of dichorionic diamniotic twins and to consider the importance of the direction of the displacement, as well as to assess the influence of the umbilical cord displacement on the placental mass and the birth weight of dichorionic diamniotic twins taking into account the direction of displacement.&#x0D; Material and methods. The study was performed on 135 dichorionic diamniotic pairs: 68 opposite-sex, 35 same-sex males, and 32 same-sex females. The impact of an absolute cord displacement from the centroid of the placental disc and the direction of its shifting were compared with the birth weight and the placental mass.&#x0D; Results. In the investigated group, a central insertion was revealed in 6 (2.2 %), eccentric – in 224 (83.0 %), marginal – in 31 (11.5 %), and velamentous – in 9 (3.3 %) cases. The first two types of cord insertion are considered to be normal, the third and the fourth are seen as abnormal. The placental mass was in a strong positive correlation with the birth weight (r=0.71, p&lt;0.0001). The placentas with an eccentric cord insertion had a smaller surface area. A negative correlation was established between the displacement of the cord insertion site and the placental mass (r=-0.4284, p&lt;0.0001) as well as the birth weight (r=-0.6115, p&lt;0.0001). The shift along the long axis was of greater importance than in relation to the shorter one. The placental mass and the birth weight were higher in the new-borns with a normal cord insertion site. In the abnormal cord insertion group, 32.5 % of the infants were under the 10th birth weight percentile, in the normal cord insertion group – only 8.3 %.&#x0D; Conclusions. The birth weight of dichorionic diamniotic twins and their placental mass are negatively correlated with the distance of the umbilical cord insertion site from the placental centre. The insertion site displacement along the long axis has a stronger negative effect on the birth weight and the placental mass in comparison with the shifting along the short axis. The placentas with an eccentric cord insertion have a smaller surface area.

Prevalence of Extraplacental Anastomoses in Monochorionic Twin Pregnancies

Objectives: To evaluate the prevalence of extraplacental anastomoses (EPA) and the factors associated. Methods: A retrospective study including 144 placentas from monochorionic diamniotic (MCDA) twins delivering at one institution was performed. EPA were defined as any intertwin anastomosis located outside the chorionic plate on macroscopic inspection. The association with perinatal factors and with umbilical cord insertion site was analyzed. Results: The prevalence of EPA was 4.9% (7/144). Velamentous cord insertion of both twins was significantly associated with the presence of EPA in the multivariate logistic regression model (p = 0.045). Discussion: EPA was found in ≈5% of MCDA twin pregnancies.

Fetal Gestational Age Determination using Ultrasound Placental Thickness.

Background:The purposes of this study are to sonographically measure the placental thickness (PT) in normal fetuses; to correlate it with gestational age (GA), fetal growth parameters, and estimated fetal weight (EFW); and to design a nomogram for the derived PT measurements.Methods:This was a hospital-based cross-sectional study on 400 women with apparently normal pregnancy within the age range of 18–45 years recruited from the Antenatal Clinic of our hospital. The fetal GA was estimated by the last menstrual period (LMP). The fetal growth parameters were determined using standard sonographic methods while the PT was measured at the level of the umbilical cord insertion site. PT was then correlated with GA, fetal growth parameters, and the EFW.Results:The mean PT (mean ± standard deviation) in the 1st, 2nd, 3rd trimesters and the whole duration of pregnancy were 14.5 ± 0.3 mm, 24.6 ± 3.9 mm, 34.8 ± 2.8 mm, and 29.6 ± 7.1 mm, respectively. PT ranged from 13.5 ± 1.9 mm at 11 weeks to 39.1 ± 0.6 mm at 40 weeks. PT (in mm) had a linear relationship and a statistically significant positive correlation with GA (in weeks) in all the trimesters, with most significant correlation recorded in the 2nd trimester (r = 0.79). There was also a statistically significant positive correlation between PT and the fetal growth parameters (biparietal diameter, head circumference, abdominal circumference, femur length and crown-rump length), and EFW. PT nomogram was developed from 11 to 40 weeks of gestation using a scatter plot with 95% confidence interval for our locality.Conclusion:PT has a linear relationship with GA, fetal growth parameters, and EFW and it can be used along with other fetal growth parameters to increase the accuracy for predicting GA in normal pregnancies, especially when the subject is not sure of or does not know her LMP.

Pattern of prenatal ultrasound diagnosed anterior abdominal wall defects at the University College Hospital, Ibadan, Nigeria: A pictorial essay

Anterior abdominal wall defects form a wide spectrum of congenital abnormalities that allow the abdominal contents to protrude through an unusual opening on the abdominal wall. These defects could be physiological or pathological depending on the time of diagnosis. They include physiological gut herniation, congenital umbilical cord hernia, omphalocele, gastroschisis, ectopia cordis, bladder exstrophy, body-stalk anomaly, Prune-Belly Syndrome, and pentalogy of Cantrell. Correct prenatal diagnosis of these anomalies with ultrasound (US) is extremely important for patient management. Evaluation of the defect relative to the umbilical cord insertion site is fundamentally important in differentiating among the various malformations. We present a pictorial essay of the spectrum of anterior abdominal wall defects diagnosed prenatally with US seen over a 5-year period at the University College Hospital, Ibadan.

Three-dimensional power Doppler ultrasound evaluation of placental blood flow in normal monochorionic diamniotic twin pregnancies

BackgroundMonochorionic diamniotic (MCDA) twin pregnancies are at higher risk of adverse outcomes and complications, which are attributed to the influence of placental morphology in MCDA twins. Monitoring of placental function is an important index for clinical decisions. The aim of our study was to evaluate the placental blood flow estimated using three-dimensional power Doppler (3D-PD) ultrasound and the vascular indices distribution with gestational age (GA) in normal MCDA twin pregnancies.MethodsOne hundred four MCDA twin pregnancies and 106 singleton pregnancies (GA range, 14–32 weeks) were included in this prospective study. 3D-PD volume data of each fetus was obtained separately from the placenta at the site of umbilical cord insertion. We analyzed the volume data using sonobiopsy technique. The placental vascularization index (VI), flow index (FI) and vascularizationflow index (VFI), were auto-calculated. The means and standard deviation values of three vascular indices per fetus were calculated and regression analysis of the vascular indices as a function of GA was performed in twin pregnancies. The vascular indices of twin and singleton pregnancies were compared using independent t-test.ResultsThere were no significant differences in VI, FI or VFI among the fetuses of twins (p > 0.05). These vascular indices increased over the course of pregnancy (p < 0.05). We obtained the regression equations for the indices as a function of GA in days: VI = exp. (4.369–28.533/GA) (R2 = 0.699, p < 0.05), FI = exp. (3.916–13.003/GA) (R2 = 0.511, p < 0.05), and VFI = exp. (3.577–37.468/GA) (R2 = 0.675, p < 0.05). There were no significant differences in three vascular indices between MCDA twin and singleton groups (p > 0.05).Conclusions3D-PD placental data using sonobiopsy technique could reflect the placental blood flow of each twin, which could be applied to the study of placental perfusion in MCDA twin pregnancies. This study also presented the vascular indices distribution with GA in normal twin pregnancies, which might be useful for early detection of MCDA complications.

AIUM-ACR-ACOG-SMFM-SRU Practice Parameter for the Performance of Standard Diagnostic Obstetric Ultrasound Examinations.

AIUM-ACR-ACOG-SMFM-SRU Practice Parameter for the Performance of Standard Diagnostic Obstetric Ultrasound Examinations.

Associations Between the Features of Gross Placental Morphology and Birthweight.

The placenta plays a critical role in regulating fetal growth. Recent studies suggest that there may be sex-specific differences in placental development. The purpose of our study was to evaluate the associations between birthweight and placental morphology in models adjusted for covariates and to assess sex-specific differences in these associations. We analyzed data from the Stillbirth Collaborative Research Network's population-based case-control study conducted between 2006 and 2008, which recruited cases of stillbirth and population-based controls in 5 states. Our analysis was restricted to singleton live births with a placental examination (n = 1229). Characteristics of placental morphology evaluated include thickness, surface area, difference in diameters, shape, and umbilical cord insertion site. We used linear regression to model birthweight as a function of placental morphology and covariates. Surface area had the greatest association with birthweight; a reduction in surface area of 83 cm2, which reflects the interquartile range, is associated with a 260.2-g reduction in birthweight (95% confidence interval, -299.9 to -220.6), after adjustment for other features of placental morphology and covariates. Reduced placental thickness was also associated with lower birthweight. These associations did not differ between males and females. Our results suggest that reduced placental thickness and surface area are independently associated with lower birthweight and that these relationships are not related to sex.