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

OBJECTIVES: To evaluate the potential connections between marginal cord insertion during the first trimester and furcate cord insertion later in pregnancy. METHODS: This 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. RESULTS: Fourteen 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). CONCLUSIONS: Marginal 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.

Development of a multivariable prediction model to identify dairy calves too young to be transported to auction markets in Canada using simple physical examination and body weight.

Calves born on Eastern Canadian dairy farms that are not kept in the herds are traditionally sold through auction markets and are raised for meat purposes such as veal calves. Since February 2020, a new Canadian federal regulation has forbidden calves <9 d old to be sold through auction markets. However, in the absence of a real-time birth registry consultation system, it would be of interest to look for predictors that could be associated with age to allow identification of calves too young to be transported. In the current retrospective cross-sectional study, 1,178 calves with a declared birth date (411 calves aged <9 d old; 34.9%) were assessed in 2 large Québec auction sites. Easy-to-record covariates [body weight (BW), breed phenotype, and presence of an umbilical cord remnant] as well as other clinical signs (umbilical swelling, enlargement, umbilical pain, wet umbilicus, skin tent, sunken eyes, ocular and nasal secretion, and hide cleanliness) were assessed. Two logistic regression models using age as a dichotomous dependent variable (<9 d old vs ≥9 d old) were built. The first model (model 1) considered all covariates, which were selected after univariable analyses and a backward stepwise selection process, whereas a more pragmatic model (model 2) only included the 3 easy-to-record variables (i.e., BW, breed, umbilical cord). Both models had similar accuracy to detect calves <9 d old (sensitivity of 38.4 and 37.5%, and specificity of 85.7 and 84.6% for model 1 and 2, respectively). Model 2 was subsequently more specifically studied as it employs a faster and easier assessment. Decision thresholds were tested for their robustness based on misclassification cost term (MCT) analysis with various prevalence of calves <9 d old and various costs of false-negative:false-positive ratio. Despite statistical significance, model accuracy, even if refined with MCT analysis, was limited at the individual level, showing the limits of using physical signs and BW or their combination as a reliable proxy of age. The sensitivity of these models to find calves <9 d old was not to be used for monitoring compliance with the Canadian federal regulation. The relatively high model specificity may help to use this model as a rule-in test (i.e., targeting positive calves for further investigation) rather than a rule-out test (due to its low sensitivity).

Biphasic Postnatal Umbilical Cord Shortening.

INTRODUCTION: Variations in postnatal length of refrigerated, unfixed umbilical cords were studied over time to elucidate natural changes and times of stability. METHODS: Length was measured in 132 cords following severance, repeated at varying timed intervals and studied by analysis of variance and regression analysis. RESULTS: Data show immediate rapid initial phase shortening (mean 4.2+/-3.9 cm SD); an interval of lengthening; stable length at hours 3-4 following severance, a slower second phase shortening (mean 1.5+/-0.7 cm SD) beginning at 5 hours and peaking at 12 hours; and gradual lengthening to stable length after 23 hours. Overall, there was a significant net mean decrease of 3.49+/-2.29 cm SD. Shortening was greatest for intact long cord segments (p=0.0001), as much as 11 cm. Two highly significant models for predicting umbilical cord length at delivery (OL) were determined using the post-delivery lengths (Length) measured at different times following delivery (Hours), as follows:At ≤ 3 hours following delivery: OL=1.02xLength cm+1.11xHoursAt >3 hours following delivery: OL=1.07xLength+0.44xHours-0.01x(Hours)2. CONCLUSION: Cord lengths stabilized between hours 3-4 and after 23 hours following severance. Phase one shortening resembles vasoconstriction; phase two resembles rigor mortis. The models allow prediction of the original umbilical cord length at delivery, regardless of the time of measurement.

Longer distance between umbilical cord insertions is associated with spontaneous twin anemia polycythemia sequence.

INTRODUCTION: The aim of the study was to investigate the placental characteristics in spontaneous twin anemia polycythemia sequence. MATERIAL AND METHODS: A retrospective case-control study of spontaneous twin anemia polycythemia sequence, twin-to-twin transfusion syndrome and normal monochorionic diamniotic twin pregnancies was performed. The primary outcome was placental characteristics. RESULTS: The prevalence of artery-artery anastomoses in spontaneous twin anemia polycythemia sequence and twin-to-twin transfusion syndrome groups was significantly lower than in the normal monochorionic diamniotic twin group (40.0% vs 33.3% vs 88.8%, respectively, P < .001). The total number of vascular anastomoses in the spontaneous twin anemia polycythemia sequence group (with range given in parentheses) was significantly lower than in the two control groups (3 [1-6] vs 5 [1-14] vs 6 [1-20], P = .001/<.001/.794). The number of artery-vein anastomoses in the spontaneous twin anemia polycythemia sequence was significantly lower than in the two control groups (2 [1-5] vs 4 [1-13] vs 5 [1-19], P = .011/.001/1.000). The total diameter of all vascular anastomoses was significantly smaller in the spontaneous twin anemia polycythemia sequence than in the two control groups (0.9 mm [0.3-4.7] vs 5.2 mm [0.8-24.6] vs 7.3 mm [1.0-25.1], P < .001/<.001/.104), as was the total diameter of artery-to-artery anastomoses (0.5 mm [0.3-1.3] vs 2.0 mm [0.5-11.8] vs 2.3 mm [0.7-9.7], P = .003/<.001/1.000) and the total diameter of artery-to-vein anastomoses (0.8 mm [0.3-2.1] vs 4.6 mm [0.8-15.3] vs 4.0 mm [0.2-21.8], P < .001/<.001/1.000). The ratio between the distance of the two umbilical cords insertion points and the placental maximum diameter in the spontaneous twin anemia polycythemia sequence group was significantly larger than in the two control groups (0.78 [0.49-0.99] vs 0.64 [0.32-1.00] vs 0.55 [0.05-1.00], P = .033/<.001/.138). CONCLUSIONS: In spontaneous twin anemia polycythemia sequence placentas, the number of superficial vascular anastomoses is lower, their diameter is smaller and the distance between the two umbilical cord insertion points is longer.

Weights of Fetal Membranes and Umbilical Cords: Correlation With Placental Pathology.

INTRODUCTION: Proper placental gross examination requires weighing the placental disc trimmed of fetal membranes and the umbilical cord. However, untrimmed placental weights are often reported, both in cases submitted for consultation and in publications. Thus, determining the contribution of membranes and cords to untrimmed placental weights would be helpful in estimating the true trimmed weight of placentas. We sought to report the average weights of membranes and cord in term placentas and to correlate these weights with common placental pathologies. METHODS: A total of 500 consecutive placentas delivered between 36 and 42 weeks gestational age were subjected to a modified grossing protocol, in which the weight of the trimmed and untrimmed placentas, fetal membranes, and umbilical cords were recorded. Acute chorioamnionitis, meconium, maternal vascular malperfusion, and fetal vascular malperfusion were included as pathologic correlates. Clinical data such as the presence of fetal hydrops, intrauterine growth restriction, intrauterine fetal demise, and maternal diabetes were also recorded. RESULTS: The mean weights of the trimmed placenta, fetal membranes, and umbilical cords were 442 g (180-805 g), 47.2 g (16-108 g), and 37.9 g (9-126 g), respectively. The fetal membranes and umbilical cord weights contributed a mean of 16% to the total untrimmed placental weight. Meconium was associated with heavier fetal membranes. Fetal vascular malperfusion was associated with longer umbilical cord and thus also with heavier umbilical cords. Maternal vascular malperfusion and intrauterine growth restriction were associated with lighter placentas. DISCUSSION: The trimmed placental disc weight may be estimated by subtracting 16% (ie, weight of the fetal membranes and umbilical cord) from the untrimmed placental weight, or alternatively by subtracting the mean weight of the membranes and umbilical cord. It is important to consider the effects of meconium, fetal and maternal vascular malperfusion, and intrauterine growth restriction on membrane and cord weights when estimating the trimmed placental disc weight.

Macroscopic evaluation of the placenta of the alpaca (Vicugna pacos).

Macroscopic evaluation of the placenta is an essential post-partum examination in the alpaca and can be of special interest in case of abortion, premature birth or stillbirth. Since there are not many reference values regarding macroscopic properties of normal alpaca placentas, a small descriptive study was conducted. Only placentae from normally foaling alpaca mares, giving birth to healthy crias, after a full-term and uneventful gestation (±350 days; range 335-360 days) were taken into account (N = 11). Crias weighed (±SD) 7.7 ± 2.25 kg (range 5.5-10 kg), while the mean weight of the full-term placentas was 0.8 ± 0.19 kg, that is 10% of the bodyweight of the crias. The weight of the allantoamnion and chorion was 0.2 ± 0.07 kg and 0.5 ± 0.13 kg, respectively. The umbilical cord length was 8.8 ± 2.84 cm, and the length of the pregnant and non-pregnant uterine horns was 69.4 ± 12.77 cm and 54.5 ± 6.81 cm, respectively. The length of the corpus was 14.6 ± 4.68 cm, and the distance from the umbilicus to the corpus was 18.5 ± 6.13 cm. The tissue volume of the allantoamnion was 0.14 ± 0.079 L, and the chorionic volume was 0.37 ± 0.078 L. The surface area of the allantoamnion and the chorion was 87.6 ± 15.56 dm2 and 72.3 ± 9.28 dm2 , respectively. All placentas had small calcifications either around the umbilical cord alone or around the umbilicus and blood vessels of the pregnant uterine horn. These measurements could be used to macroscopically evaluate alpaca placentas, although more research is needed to extend our knowledge of macroscopic evaluation of normal and abnormal placentas.

An observation of umbilical coiling index in a low risk population in Nigeria.

OBJECTIVES: The umbilical coiling index (UCI) is one of cord parameters for foetal assessment with limited studies in our environment. With recent advances in its evaluation, its significance, pattern, abnormalities and correlates need to be defined in our parturients. METHODS: The umbilical cords of 436 neonates were examined. Gross examination was done within 5 min of delivery. The UCI was defined as the number of complete coils per centimetre of cord. Normal UCI was defined as values between the 10th and 90th percentiles of the study population. RESULTS: The mean umbilical cord length was 52.7±11.5 cm, mean number of coils was 10.8±5.1 and mean UCI was 0.21±0.099. The range was between 0.0 and 1.0. UCI values of 0.13 and 0.30 were 10th and 90th percentiles, respectively. Normal UCI was observed in 351 (80.5%) neonates, 44 (10.4%) and 41 (9.1%) had hypo- and hypercoiled cords, respectively. Congenital abnormalities occurred in the normocoiled and hypercoiled groups but was not demonstrated in the hypocoiled group. The mean value of UCI in neonates with congenital abnormalities was 0.29±0.12 (P=0.011). There was no significant statistical relationship between foetal outcome and degree of UCI. CONCLUSION: The UCI was not associated with adverse perinatal outcome in this study.

Hypercoiling of the umbilical cord in uncomplicated singleton pregnancies.

BACKGROUND: The umbilical coiling index (UCI) is a measure of the number of coils in the umbilical cord in relation to its length. Hypercoiled cords with a UCI of >0.3 coils/cm have been associated with adverse fetal and neonatal outcomes. AIMS: The primary aim is to determine the accuracy of UCI measured on second trimester ultrasound in predicting UCI at birth. The secondary outcome is to investigate the association between hypercoiling of the umbilical cord on prenatal ultrasound and adverse maternal, fetal and neonatal outcomes. METHODS: This was a prospective cohort study of uncomplicated singleton pregnancies. Seventy two patients were included in the study. UCI was measured in the second trimester ultrasound, and compared to UCI measured postnatally. Outcomes of patients with hypercoiled cords on ultrasound were compared to outcomes of patients with normocoiled cords. RESULTS: Our results failed to show a strong correlation between the UCI determined with ultrasound, and the UCI determined with examination of the umbilical cord after delivery. We also did not demonstrate that measurement of the UCI on second trimester ultrasound is able to predict adverse maternal, fetal or neonatal outcomes. CONCLUSION: This study suggests that measurement of the umbilical coiling index should not be part of routine second trimester sonography in patients with uncomplicated singleton pregnancies, with no other medical or surgical comorbidities.

Difference in the size of the placenta and umbilical cord between women with natural pregnancy and those with IVF pregnancy.

PURPOSE: The purpose of this study was to compare the sizes of the placenta and umbilical cord in women with natural pregnancy versus those undergoing in vitro fertilization (IVF). METHODS: Overall, 1610 cases of uncomplicated single pregnancies with vaginal delivery at ≥ 37 weeks of gestation were included in this study. The patients were divided into two groups: natural pregnancy group (n = 1453) and IVF pregnancy not including intracytoplasmic sperm injection (ICSI) treatment (n = 157). The groups were compared in terms of gestational week, maternal age, parity, maternal weight gain, prepregnancy maternal BMI, infant weight at birth, infant head circumference, placental weight, cross section of the placenta, cross section of the umbilical cord, insertion site of the umbilical cord, and umbilical cord length. Stepwise selection and multivariate logistic regression were used for statistical analysis to correct the result as an independent factor. RESULTS: There was no difference in the size of the placenta and umbilical cord between women with natural pregnancy and with IVF, but the incidence of velamentous insertion of the cord was significantly increased in women with IVF pregnancy (adjusted odd ratio [AOR] 1.72, 95% confidence interval [CI] 1.08-2.72, p = 0.026). CONCLUSIONS: Although there is no difference in placental weight and cord size, velamentous insertion of the umbilical cord increases in IVF pregnancy and needs careful observation during the delivery process.

Umbilical Cord Diameter at the Junction of the Body Wall in the Newborn. Is It a Biomarker for Congenital Umbilical Hernia?

INTRODUCTION: The aim is to obtain normal newborn umbilical cord diameters for use it in the evaluation of congenital umbilical hernia. MATERIALS AND METHODS: The umbilical cord diameter (UCD) at the abdominal wall, maternal age, birth weight, gestational age at birth, birth height, head, chest and abdominal circumferences, and the time of measurement after birth was noted. RESULTS: Mean ± standard deviation and median (minimum-maximum) values of the UCD were 9.9 ± 1.9 mm, 10.0 (5-16 mm), respectively. There was a significance for a positive low correlation between birth height and UCD (p = .039, r = .143). No other birth parameter had a significant correlation with UCD. The gender of the newborn (p = .95) and the type of delivery (p = .056) did not affect UCD. CONCLUSION: These data may be used in determining the normality of UCD, which could be helpful in the evaluation of umbilical hernias.

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

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

Incidence of and risk indicators for vasa praevia: a systematic review.

BACKGROUND: Vasa praevia (VP) is a rare phenomenon that is assumed to increase the risk of severe complications, including fetal death. Critical data on its incidence are lacking, so there is no rational basis for prenatal screening. OBJECTIVES: To review the literature on the incidence and risk indicators for VP. SEARCH STRATEGY: We searched OVID MEDLINE, OVID EMBASE, the Cochrane Library and PubMed for case-control and cohort studies on incidence and risk indicators for VP. SELECTION CRITERIA: Two reviewers selected studies and scored their methodological quality. DATA COLLECTION AND ANALYSIS: We calculated the mean incidence of VP. We constructed 2 × 2 tables cross-classifying potential risk indicators against the incidence of VP to calculate common odds ratios and 95% confidence intervals, using the Mantel-Haenszel method. MAIN RESULTS: We included 13 studies (two prospective cohort studies, ten retrospective cohort studies and one case-control study) reporting on 569 410 patients with 325 cases of VP. Based on ten included cohort studies providing information on the incidence, the mean incidence of VP was 0.60 per 1000 pregnancies. We identified five different risk indicators and markers for VP: second-trimester placenta praevia, conception by assisted reproductive technologies, a bilobed or succenturiate placenta, umbilical cord insertion in the lower third part of the uterus at first-trimester ultrasound and velamentous cord insertion. Almost 83% of the cases of VP had one or more risk indicators. AUTHORS' CONCLUSIONS: In view of the low incidence, screening for VP in an unselected population is not advised. Targeted screening of women with one or more risk indicators as a part of routine mid-gestation scanning should be considered. TWEETABLE ABSTRACT: Vasa praevia is more common in placenta praevia, conception by ART, velamentous cord insertion and bilobed placenta.

Relationship Between Short Umbilical Cord Length and Adverse Pregnancy Outcomes.

To investigate how umbilical cord length relates to pregnancy outcomes, we retrospectively analyzed data from 89,042 deliveries recorded in the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System. We included term deliveries in which vaginal birth was attempted. Umbilical cord length was categorized into four groups: less than the first percentile, from the first percentile to less than the 10th percentile, from the 10th percentile to less than 25th percentile, and from the 25th percentile to less than the 75th percentile, which constituted the control group. Cord lengths of 33, 43, 48, 63 cm corresponded to the first, 10th, 25th, and 75th percentile values of the cord length distribution, respectively. Statistically significant differences were observed in the rate of unplanned cesarean delivery for all three short cord groups compared to control. There was a higher odds ratio for unplanned cesarean delivery as the umbilical cord became shorter.

Correlation between Umbilical Cord Diameter and Cross Sectional Area with Gestational Age and Foetal Anthropometric Parameters.

The objective of the study was to find out correlation between umbilical cord diameter, cross sectional area with gestational age and foetal anthropometric parameters. This cross sectional study was conducted among healthy women between the 24(th) and 40(th) completed weeks of a normal pregnancy in the Department of Radiology & Imaging, Mymensingh Medical College Hospital, Mymensingh during the study period, from July 2009 to June 2011. A total of 230 consecutive normal pregnancy patients were included in the study. The diameter & cross-sectional area of the umbilical cord were measured on a plane adjacent to the junction of the umbilical cord and the fetal abdomen, in cross-section, with maximum magnification of the image. The cord was manually circled, and it's cross sectional areas was automatically calculated by the ultrasonograph. The mean±SD age was 24.3±4.7 years with range from 19 to 36 years. The mean gestational age was 32.1±4.5 weeks and more than a half (56.4%) of the pregnant women were nulliparas. A positive significant (p<0.001) correlation were found between umbilical cord diameter with bi-parietal diameter (r=0.548); head circumference (r=0.411); abdominal circumference (r=0.444); femur length (r=0.366) and gestational age gestation age (r=0.643). Similarly, a significant (p<0.001) positive week correlation were found between umbilical cross sectional area with bi-parietal diameter (r=0.3303); head circumference (r=0.3202); abdominal circumference (r=0.2651); femur length (r=0.3307) and gestation age (r=0.4051). A positive significant better correlation was found with umbilical cord diameter than cross sectional area with foetal anthropometric parameters.

Longitudinal reference range for umbilical cord cross-sectional area in twin pregnancies at 18-32 weeks of gestation.

OBJECTIVES: The objectives of this study were to establish gestational age-specific reference ranges for cross-sectional area of the umbilical cord, and its components, in twin pregnancies and to compare them with previously reported singleton reference ranges. METHODS: This was a prospective longitudinal study involving uncomplicated dichorionic twin pregnancies. Sonographic measurements of the cross-sectional area of the umbilical cord, umbilical vein and arteries and Wharton's jelly were obtained in a plane adjacent to the fetal abdomen, every 3 weeks, between 18 and 32 weeks of gestations. Multilevel regression analysis was used to determine gestational age-specific reference ranges for each parameter, and these were plotted against singleton pregnancy references. RESULTS: Three hundred and thirty four ultrasound scans were performed in 44 twin pregnancies, between 18 and 32.9 weeks (mean: 3.8 ± 0.7 scans/pregnancy and mean interval between scans: 3.3 ± 0.9 weeks). All umbilical cord cross-sectional areas (total, vein, artery and Wharton's jelly) showed a significant increase with gestational age. Compared with singleton pregnancy ranges, mean values were considerably lower in twin pregnancies and resemble the lower limits observed in singletons. CONCLUSION: In twin pregnancies, cross-sectional area of the umbilical cord, and its components, increases between 18 and 32 weeks, and mean values are substantially lower compared with singleton pregnancies.

Antenatal umbilical coiling index as a predictor of perinatal outcome.

PURPOSE: To evaluate the relationship between sonographic measurements of umbilical cord coiling index during late second trimester of pregnancy and perinatal outcome. METHODS: This prospective study was conducted on two hundred pregnant women with uncomplicated, singleton pregnancy between 20 to 24 weeks of gestation. The antenatal umbilical coiling index (UCI) was calculated by doing a transabdominal ultrasound at the time of induction into the study as the reciprocal of the pitch of one complete vascular coil. The patients were followed up till delivery and any adverse antenatal and/or perinatal event was noted. RESULTS: The mean value for the UCI was noted to be 0.36 + 0.07 coils/cm with a 95% CI of 0.35-0.37. The values for the 10th and the 90th percentile were 0.26 and 0.46 coils/cm respectively. Accordingly the cases were divided into three groups- hypocoiled (UCI <10th percentile)-18, normocoiled (UCI between 10th-90th percentile)-162 and hypercoiled (UCI >90th percentile)-20. Hypocoiling was observed to be significantly associated with preterm labour pains (P value 0.0344), oligohydramnios (P value 0.0021), intrapartum foetal heart rate abnormalities (P value 0.0012), instrumental vaginal delivery (P value 0.0275) and low birth weight (P value 0.0344). Hypercoiling was found to be significantly associated with intrauterine growth restriction (P value 0.0323), foetal heart rate abnormalities during labour (0.0399) and low birth weight (P value 0.0095). CONCLUSION: Abnormal umbilical coiling index in the form of either hypo- or hypercoiling is associated with several adverse antenatal and neonatal outcomes.

[Study of reconstruction of digital three-dimensional model of normal human placental vascular network based on MRI data in vitro].

OBJECTIVE: To investigate the reconstruction of digital three-dimensional (3D) model of normal human placental vascular network based on MRI data in vitro. METHODS: Six full term placentas were collected, casted with modified self-curing denture base resin and scanned by T1 e-THRIVE high resolution magnetic resonance imaging. MRI images were imported into Mimics 14.0 software for 3D reconstruction, and the 3D model was compared with placental vascular casting model. RESULTS: (1) The placental vascular network could be obtained on MR 2D images. The 3D model were reconstructed successfully, which showed clear, realistic images. The 3D model could be zoomed and revolved from any direction to observe the branches of arteries and veins. (2) The umbilical vein and 2 umbilical arteries could be seen in the 3D model. In the root of the umbilical cord, the umbilical vein divided into 5-7 branches. While the 2 umbilical arteries anatomoses to form blood sinus and then devided into sub-branches. All the peripheral vessels ended in chorionic plate with abundant sub-branches. (3) When compared with the casting of placental arterial-venous vascular network, the morphology, structure, angle and trend of vessels in 3D model was consistent with the casting network. CONCLUSIONS: Reconstruction of digital 3D model of normal human placental vascular network based on MRI in vitro is a new and promising method for the study of placental vasculature. It has better vascular exposure, free rotation, radiation-free. It provides a promising base for the study of placental vasculature in vivo in the future.

Fetal external features and morphology of the umbilical cord of wild boars.

This study aimed to describe the gestational and morphological aspects of the fetuses and their respective umbilical cords from two pregnant wild boars (Sus scrofa). Morphological descriptions were provided for 23 fetuses and the gestational ages were estimated through fetal characteristics and formula application. The specimens were fixed in 10% formalin for subsequent macroscopic and microscopic examination. Histological characterization was performed using haematoxylin-eosin (H&E), Masson's trichrome (MT) and Verhöeff's staining techniques. The wild boar fetuses exhibited an estimated gestational age of 55 days (in the larger uterus) and 45 days (in the smaller uterus). They displayed well-developed features consistent with domestic pig fetuses, except for the presence of five pairs of mammae. Additionally, the umbilical cord consisted of two arteries, one vein, an allantoic duct, and a vitelline duct (the latter two identified only microscopically), located in the juxtafetal, intermediate and juxtaplacental portions. The arteries and veins were comprised of endothelium, smooth muscle and collagen fibres, with no elastic fibres observed in the vessel walls. The allantoic duct was lined with simple cuboidal epithelium, while the vitelline duct featured a simple squamous epithelium. In conclusion, the morphological characteristics observed in the examined structures align with the expected patterns for species of the Suidae family. Furthermore, these findings contribute substantially to the morphological characterization of the wild boar, yielding valuable insights into the fetal morphology and the structure of the umbilical cord.

Evaluation of antenatal umbilical coiling index at 16-21 weeks of gestation as a predictor of trisomy 21 and other chromosomal defects.

OBJECTIVES: To determine whether there is an association between sonographically assessed hyper- or hypocoiling of the umbilical cord and the presence of trisomy 21, to provide reference values for the antenatal umbilical coiling index (aUCI) at a gestational age of 16-21 weeks and to determine whether these measurements are reliable and reproducible. METHODS: This was a prospective study of 737 pregnancies in which the aUCI was measured between 16 and 21 weeks of gestation by ultrasound at the time of amniocentesis. The aUCI was calculated as the reciprocal value of the mean length of one complete coil in centimeters. We created reference curves and studied the relationship with trisomy 21 and other chromosomal defects. In 30 pregnancies we studied the intra- and interobserver variation in measurements using Bland-Altman plots with associated 95% limits of agreement and intraclass correlation coefficients. RESULTS: aUCI was found to be non-linearly related to gestational age at 16-21 weeks and reference curves were created for the mean aUCI and the 2.3(rd) , 10(th) , 90(th) and 97.7(th) percentiles. There was no significant difference in aUCI values between the reference group (n = 714) and cases with trisomy 21 (n = 16) or other aneuploidies (n = 7) (one-way ANOVA, P = 0.716). There was good intra- and interobserver agreement in aUCI measurements. CONCLUSIONS: The aUCI can be measured reliably and varies according to gestational age at 16-21 weeks. The aUCI was not significantly associated with trisomy 21 or other chromosomal defects.

Relationship between the umbilical cord coiling index and the umbilical blood flow at 11-13 weeks of gestation.

OBJECTIVES: The aim of this study was to clarify the effects of umbilical cord coiling on the umbilical blood flow at 11-13 weeks of gestation. METHODS: A cross-sectional study was conducted among consecutive pregnant females at 11-13 weeks of gestation. Transabdominal ultrasound examinations were performed to obtain the umbilical coiling index (CI), the maximum umbilical arterial peak velocity at the free loop, the venous velocities at the free loop and the umbilical ring, and the umbilical arterial and venous flow volumes. After every measurement was standardized according to the crown-rump length (CRL), correlations between the CI and these measurements were analyzed. RESULTS: A total of 364 subjects were enrolled. The CI significantly decreased in association with advancing gestation. There were significant correlations between the CRLs and the umbilical arterial peak velocities, the venous velocities at the free loop and the umbilical ring, and the umbilical arterial and venous flow volumes. The z-scores of the umbilical arterial and venous velocimetries exhibited no significant correlations with the CI. The umbilical arterial and venous flow volumes were also not found to correlate with the CI. CONCLUSIONS: The CI does not affect either the umbilical arterial or venous blood flow at 11-13 weeks of gestation.