Influence of the umbilical cord insertion site on the optimal individual birth weight achievement

Maternal background and perinatal complications in MCI: A retrospective cohort study

OBJECTIVE

Marginal cord insertion (MCI) is often defined as an abnormal placental cord insertion (PCI), yet there is limited discussion on the maternal backgrounds and perinatal complications associated with its occurrence. This retrospective cohort study aimed to investigate maternal backgrounds associated with MCI and to compare perinatal outcomes between MCI and normal PCI.

MATERIALS AND METHODS

The study included 1038 deliveries from 2021 to 2023 in our institution, examining maternal backgrounds and perinatal outcomes. Multivariable logistic regression analysis was conducted for variables that showed significance in univariate analysis of maternal backgrounds. For perinatal outcomes, variables that exhibited significance were further analyzed using multivariable logistic regression, considering factors previously reported to be associated with those events.

RESULTS

9.5 % exhibited MCI. Assisted reproductive technology, nulliparous, and congenital uterine anomalies were identified as independent risk factors for MCI. In perinatal outcomes, fetal growth restriction (FGR) and emergency cesarean section were significantly more prevalent in cases with MCI. Even when compared to factors previously reported to be associated with FGR and emergency cesarean section, MCI remained an independent risk factor.

CONCLUSION

In addition to previously reported factors such as ART and primiparity, uterine anomalies were also identified as risk factors for MCI. It is important to manage MCI with the awareness that it increases the incidence of perinatal complications.

The Interplay of Molecular Factors and Morphology in Human Placental Development and Implantation

The placenta is a vital organ that supports fetal development by mediating nutrient and gas exchange, regulating immune tolerance, and maintaining hormonal balance. Its formation and function are tightly linked to the processes of embryo implantation and the establishment of a robust placental-uterine interface. Recent advances in molecular biology and histopathology have shed light on the key regulatory factors governing these processes, including trophoblast invasion, spiral artery remodeling, and the development of chorionic villi. This review integrates morphological and molecular perspectives on placental development, emphasizing the roles of cytokines, growth factors, and signaling pathways, such as VEGF and Notch signaling, in orchestrating implantation and placental formation. The intricate interplay between molecular regulation and morphological adaptations highlights the placenta's critical role as a dynamic interface in pregnancy. This review synthesizes current findings to offer clinicians and researchers a comprehensive understanding of the placenta's role in implantation, emphasizing its importance in maternal-fetal medicine. By integrating these insights, the review lays the groundwork for advancing diagnostic and therapeutic approaches that can enhance pregnancy outcomes and address related complications effectively.

Placental cord insertion migration: Implications for ultrasound documentation and follow-up of abnormal placental cord insertion site

Introduction/Purpose

It is well-documented in the literature that the placenta migrates during pregnancy; however, studies regarding placental cord insertion (PCI) migration are scarce. This longitudinal, prospective study aimed to determine whether PCI migration is a true phenomenon, to assess whether the PCI can change classification during pregnancy and to determine the validity of PCI site documentation including follow-up of abnormal PCI.

Methods

Eighty-three participants who had first, second and third trimester ultrasound examinations at a Western Australian private imaging practice over a 12-month period between November 2021 and November 2022 were recruited. The measured distance of the lower margin of the placenta to the cervix, the distance of the PCI to the closest placental edge and the PCI classification were documented in each trimester. Data analysis was conducted to determine PCI migration rates during pregnancy and to test for association between PCI migration and maternal and placental factors.

Results

The PCI migrated during pregnancy and the PCI classification has the potential to evolve. All identifiable PCIs that were normal in first trimester remained so throughout the pregnancy. The majority (67.6%) of cord insertions that were marginal in first trimester progressed to a normal insertion site by third trimester; 23.5% remained marginal and 8.8% evolved to a velamentous insertion. Three velamentous cord insertions were recorded in first trimester, none of which normalised-two remained velamentous during the pregnancy and one evolved to marginal in second trimester. Marginal cord insertions (MCIs) ≤10 mm from the placental edge in second trimester remained marginal in third trimester; MCIs that were >15 mm from the placental edge in second trimester normalised in third trimester.

Conclusions

Placental cord insertion migration is a phenomenon that occurs during pregnancy with the potential for PCI classification to evolve. Due to the association between abnormal PCI and perinatal complications, coupled with the potential for marginal cord insertion to evolve, documentation of PCI and follow-up of abnormal PCI is beneficial, particularly in cases of velamentous insertion and marginal insertion at the placental edge or in the lower uterus.

The impact of chewing khat during pregnancy on selected pregnancy outcomes in eastern Ethiopia: A cohort study with a generalized structural equation modeling analysis approach

INTRODUCTION

Little is known about the fetal and pregnancy effects of khat chewing during pregnancy. The aim of the current study was to determine the impact of chewing khat during pregnancy on selected pregnancy outcomes in Ethiopia, 2022: A Cohort Study with a Generalized Structural Equation Modeling Analysis Approach.

METHODS

An institution-based prospective cohort study was employed in selected hospitals in eastern Ethiopia. Pregnant women who visited the selected hospitals in the study area during the study period that fulfilled the eligibility criteria were included until a sample size (344) was fulfilled. The main outcomes studied in the present study were preterm birth and low birth weight. Data were collected through anthropometric and clinical measurements, and interviewers administered questionnaires. The survival analysis and generalized linear model analysis were performed to estimate the crude and adjusted relative risk and attributable risk. The Generalized Structural Equation Modeling (GSEM) analysis was performed using the Statistical software for data science (Stata) 'GSEM' command to examine the mediation effect.

RESULTS

The risk of occurrence of preterm birth was significantly higher among khat chewers [adjusted relative risk (aRR) = 2.19; 95%CI 1.21-3.96]. In further analysis after adjusting for gestational hypertension and cesarean delivery, the regression coefficient of khat chewing during pregnancy on preterm birth has been decreased in size from path n, β = 0.37, p<0.001 to path n', β = 0.15, p<0.005. The risk of occurrence of low birth weight among khat chewers was significantly higher (aRR = 4.17; 95%CI 2.11-8.25). In further analysis after adjusting for gestational hypertension, cesarean delivery, preterm birth and maternal anemia, the regression coefficient of khat chewing during pregnancy on low birth weight has been decreased in size from path q, β = 0.4, p<0.001 to path q', β = 0.2, p<0.001.

CONCLUSION

Overall, the present study revealed that khat chewing is not only a worry of the current population but also a public health concern of the generation affecting unborn fetuses.

The effect of possible mediators on the association between chewing khat during pregnancy and fetal growth and newborn size at birth in Eastern Ethiopia

INTRODUCTION

Restriction in the growth of the fetus is a leading cause of stillbirth, neonatal mortality, and short- and long-term morbidity. Documented existing scientific evidence have shown the effects of maternal drugs use, alcohol drinking, tobacco smoking, cocaine use and heroin use on fetal growth restriction. However, data is lacking on the effects of khat chewing during pregnancy on fetal growth status and newborn size at birth. Therefore, the aim of the present study was to measure the effect of chewing khat during pregnancy on fetal growth and size at birth in eastern Ethiopia.

METHOD

A cohort study was conducted in selected health institutions in eastern Ethiopia. All pregnant women fulfilled the eligibility criteria in the selected health institutions was the source population. The calculated sample size of exposed and unexposed groups included in the study, in total, was 344. Data collection was performed prospectively by interviewers administered questionnaires, and anthropometric, clinical and ultrasound measurements. Data was analyzed using SPSS version 27 and STATA version 16 software. The survival analysis (cox proportional hazards model) and generalized linear model (GLM) for the binomial family analysis were performed to estimate the crude and adjusted relative risk and attributable risk (AR) with corresponding 95% CI of chewing khat on fetal growth restriction. The mediation effect has been examined through Generalized Structural Equation Modeling (GSEM) analysis using the Stata 'gsem' command. Statistically significant association was declared at p-value less than 5%.

RESULTS

In the present study, the incidence of fetal growth restriction (FGR) among the study cohorts was 95 (29.7%); of this, 81 (85.3%) were among khat chewer cohorts. The relative risk of fetal growth restriction among khat chewer cohort mothers was significantly higher (aRR = 4.32; 95%CI 2.62-7.12). Moreover, the incidence of small for gestational age at birth among the present study cohorts was 100 (31.3%); 84 (84%) were from khat chewer cohorts' deliveries. More importantly, in the present study, 98.95% of the ultrasound-identified fetuses with FGR were found to be SGA at birth. Hence, in the current study, FGR was highly associated with SGA at birth. In additional analysis, the regression coefficient of khat chewing during pregnancy on fetal growth restriction has been decreased in size from path o, β = 0.43, p < 0.001 to path o', β = 0.32, p < 0.001, after adjusting for gestational hypertension and maternal anemia.

CONCLUSION

In sum, the present study showed khat chewing during pregnancy is not simply affected the mothers, but it also affected the unborn fetuses. Therefore, the health workers as well as the local community and religious leaders should give high emphasis on provision of health education regarding the damage of chewing khat by pregnant mothers, with especial focus of the effects on their fetuses.

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.

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

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

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.

Placental apoptotic markers are associated with placental morphometry

INTRODUCTION

Preeclampsia is a hypertensive disorder affecting both mother and the fetus and is a major cause of maternal and neonatal morbidity and mortality. Abnormal placentation is a common feature in preeclampsia that contributes to placental dysfunction. It is likely that increased homocysteine and oxidative stress influence apoptosis in preeclampsia. Increased placental apoptosis may aggravate the symptoms of preeclampsia through disruption of the placental structure. The current study aims to examine the association between various placental apoptotic markers with placental dimensions and maternal and neonatal characteristics in women with preeclampsia.

METHODS

A total of 80 pregnant women [preeclampsia (n = 40); normotensive control (n = 40)] were included in the study. Placental characteristics such as its major axis, minor axis, breadth, thickness (at centre, cord insertion and periphery) and trimmed placental weight were recorded.Placental protein levels of caspase-3, caspase-8, BAX and Bcl-2 were estimated by ELISA and gene expression were examined by real time quantitative PCR.

RESULT

Protein levels of proapoptotic markers such as caspase-8 and 3 were higher (p < 0.01) in the preeclampsia group compared to control whereas, the level of antiapoptotic marker Bcl-2 (p < 0.05) was lower in the preeclampsia group. Caspase-3 and Bcl-2 protein levels were negatively associated with thickness of placenta at cord insertion (p < 0.01). Protein levels of caspase-8 and caspase-3 were positively associated with placental MDA levels (p < 0.01). Caspase-8 was negatively associated with baby length (p = 0.055).

DISCUSSION

This study demonstrates the association of various apoptotic markers with oxidative stress and placental dimensions.

Morphological and histopathological changes in placentas of pregnancies with intrauterine growth restriction

Aim: The definition of fetal growth restriction (FGR) refers to the incapability of a fetus to achieve the appropriate estimated growth, with expected fetal weight below the 10^th percentile calculated for its gestational age. Placental factors and hypoxemia are considered to be essential elements with influence on intrauterine growth restriction (IUGR) and fetal death. The purpose of the present study was to investigate the macroscopic and microscopic pathological findings regarding the placentas in pregnancies complicated by influence on IUGR. Patients, Materials and Methods: Our study included 42 third-trimester pregnant patients admitted to the Cuza Vodă Hospital of Obstetrics and Gynecology, Iaşi, Romania, in the last three years. Soon after delivery, the 42 placentas were collected and analyzed; 32 placentas came from cases previously diagnosed with influence on IUGR and were included in our study group. Ten other placentas included in the control group were selected from uncomplicated pregnancies. Standard Hematoxylin–Eosin (HE) staining method, as well as Periodic Acid–Schiff (PAS) staining, and immunohistochemical techniques for cluster of differentiation 31 (CD31) and collagen IV were used in order to highlight the morphological features of the studied placentas. Results: Our study revealed that reduced placental dimensions and eccentric umbilical cord insertion are correlated with the birthweight of the fetuses with IUGR (p<0.05). The most common histological finding in our study group was placental infarction later correlated with IUGR, but a certain causality could not be demonstrated, as this finding was also present in normal pregnancies. Other histopathological findings were also present in the influence on IUGR group, such as fibrin deposits, diffuse calcification, chronic villitis, avascular chronical villi, with no significant statistical correlations. CD31 was strongly immunoexpressed in the villous endothelial cells. Collagen IV presented a strong immunoreaction in the basement membrane and mesenchyme of the placental villi. Conclusions: Our study revealed a correlation between the dimensions of the diameters and volume of the maternal placenta and the presence of influence on IUGR. Moreover, it confirms the available data suggesting that the place of insertion of the umbilical cord is correlated with the weight of the fetus. Further studies with extended panel antibodies are needed in order to determine and complete the role of these morphological changes in the development of influence on IUGR.

Placenta morphology and biomarkers in pregnancies with congenital heart disease - A systematic review

Impaired placentation is an important contributing factor to intra-uterine growth restriction and pre-eclampsia in fetuses with congenital heart defects (CHD). These pregnancy complications occur more frequently in pregnancies with fetal CHD. One of the most important factors influencing the life of children with CHD is neurodevelopmental delay, which seems to start already in utero. Delayed neurodevelopment in utero may be correlated or even (partly) explained by impaired placentation in CHD cases. This systematic review provides an overview of published literature on placental development in pregnancies with fetal CHD. A systematic search was performed and the Newcastle-Ottawa scale was used to access data quality. Primary outcomes were placenta size and weight, vascular and villous architecture, immunohistochemistry, angiogenic biomarkers and/or placental gene expression. A total of 1161 articles were reviewed and 21 studies were included. Studies including CHD with a genetic disorder or syndrome and/or multiple pregnancies were excluded. Lower placental weight and elevated rates of abnormal umbilical cord insertions were found in CHD. Cases with CHD more frequently showed microscopic placental abnormalities (i.e. abnormal villous maturation and increased maternal vascular malperfusion lesions), reduced levels of angiogenic biomarkers and increased levels of anti-angiogenic biomarkers in maternal serum and umbilical cord blood. Altered gene expression involved in placental development and fetal growth were found in maternal serum and CHD placentas. In conclusion, abnormal placentation is found in CHD. More extensive studies are needed to elucidate the contribution of impaired placentation to delayed neurodevelopment in CHD cases.

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. 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. 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<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<0.0001) as well as the birth weight (r=-0.6115, p<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 %. 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.

Marginal cord insertion among singleton births at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia

BACKGROUND

Umbilical cord may insert abnormally i.e. marginal insertion to a placenta which can cause different birth and perinatal complications. Despite the increased effort taken by different responsible bodies, the prevalence of birth and perinatal complications are still high, possibly due to anomalous cord insertion. So far, anomalous cord insertion lacks proper attention in different medical settings. Hence, the present study aims to assess the magnitude, risk factors, and adverse birth outcomes of marginal cord insertion among singleton births.

METHODS

An institution-based cross-sectional study design was conducted. A systematic random sampling technique was used to select study participants. Data were collected by using a structured questionnaire and it was entered into epi-data version 3.1 then exported to SPSS version 20 for data cleansing and analysis. Bi-variable and multivariable logistic regressions were employed to identify risk factors and adverse outcomes associated with marginal cord insertions. Crude and adjusted odds ratio (P-value < 0.05) with a 95% confidence interval were calculated.

RESULT

The magnitude of marginal cord insertion was 6.4% (95% CI = 4.4-8.8%) in singleton pregnancies. Independent risk factors for marginal cord insertion were advanced maternal age (AOR = 2.24, 95% CI: 1.35-11.08), primiparity (AOR = 1.98, 95% CI: 1.37-8.69), maternal chronic hypertension (AOR = 3.07, 95% CI: 1.66-9.76), previous cesarean delivery (AOR = 2.51, 95% CI: 1.43-10.21), and use of intrauterine contraceptive device before pregnancy (AOR = 2.22, 95% CI: 1.36-12.30). Pregnancies complicated by marginal cord insertion are at higher risk to develop low birth weight (AOR = 2.89, 95% CI: 1.23-6.80), preterm birth (AOR = 4.00, 95% CI: 1.44-11.14), and emergency cesarean delivery (AOR = 3.68, 95% CI: 1.03-13.81).

CONCLUSION AND RECOMMENDATION

Marginal cord insertion is a mistreated potential risk for low birth weight, preterm birth, and emergency cesarean delivery. Routine screening of marginal cord insertion should be considered in pregnancies with advanced age, nulliparity, hypertensive disorder, history of cesarean section, and intrauterine contraceptive device usage before pregnancy.

Incidence and risk factors for velamentous umbilical cord insertion in singleton pregnancies after assisted reproductive technology

AIM

Assisted reproductive technology (ART) is gaining popularity worldwide. However, it is associated with increased incidence of velamentous umbilical cord insertion (VCI) in the placenta, resulting in adverse perinatal outcomes. This study aimed to identify the risk factors that might affect the incidence of VCI in pregnancies after ART treatment.

METHODS

We retrospectively analyzed the records of 906 singleton pregnancies via ART; all women delivered in our facility. Three ART-related variables and infant sex were examined: (1) fertilization method (conventional in vitro fertilization or intracytoplasmic sperm injection), (2) type of embryo at the time of transfer (fresh or frozen-thawed), (3) developmental stage of embryo at the time of transfer (cleavage stage or blastocyst), and (4) infant sex (male or female). Logistic regression analysis was used to assess the impact of these variables on the incidence of VCI.

RESULTS

Of 906 cases, 55 had VCI (incidence rate, 6.1%). After adjusting for potential confounders, blastocyst stage of development (adjusted odds ratio [aOR]: 4.3, 95% confidence interval [CI]: 1.9-12.7) and female sex (aOR: 2.2, 95% CI: 1.2-3.9) emerged as independent risk factors for the development of VCI. The fertilization method and type of embryo at the time of transfer did not affect the incidence of VCI.

CONCLUSIONS

Blastocyst stage of development and female sex pose a higher risk for developing VCI. Thus, more attention should be paid to pregnancies achieved by blastocyst and with a female fetus to detect VCI proactively and safeguard the health of both mother and fetus/neonate.

The Emerging Role of the Prokineticins and Homeobox Genes in the Vascularization of the Placenta: Physiological and Pathological Aspects

Vasculogenesis and angiogenesis are key processes of placental development, which occur throughout pregnancy. Placental vasculogenesis occurs during the first trimester of pregnancy culminating in the formation of hemangioblasts from intra-villous stem cells. Placental angiogenesis occurs subsequently, forming new blood vessels from existing ones. Angiogenesis also takes place at the fetomaternal interface, allowing essential spiral arteriole remodeling to establish the fetomaternal circulation. Vasculogenesis and angiogenesis in animal models and in humans have been studied in a wide variety of in vitro, physiological and pathological conditions, with a focus on the pro- and anti-angiogenic factors that control these processes. Recent studies revealed roles for new families of proteins, including direct participants such as the prokineticin family, and regulators of these processes such as the homeobox genes. This review summarizes recent advances in understanding the molecular mechanisms of actions of these families of proteins. Over the past decade, evidence suggests increased production of placental anti-angiogenic factors, as well as angiogenic factors are associated with fetal growth restriction (FGR) and preeclampsia (PE): the most threatening pathologies of human pregnancy with systemic vascular dysfunction. This review also reports novel clinical strategies targeting members of these family of proteins to treat PE and its consequent effects on the maternal vascular system.

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.

Antenatal Diagnosis of Marginal and Velamentous Placental Cord Insertion and Pregnancy Outcomes

OBJECTIVE

To evaluate the association between antenatal diagnosis of velamentous and marginal placental cord insertions with adverse perinatal outcomes of small-for-gestational-age (SGA) birth weight (less than the 5th percentile), caesarean birth, and perinatal mortality.

METHODS

Using a diagnostic imaging database, we performed a cohort study of all consecutive singleton pregnancies (35,391), including 1,427 cases of marginal and 107 cases of velamentous cord insertion, delivered after 24 6/7 weeks of gestation between January 1, 2012, and December 31, 2015, at a single Canadian tertiary care center. Cases with placenta previa, vasa previa, no documented cord insertion, or fetal anomalies were excluded.

RESULTS

In the overall cohort, the rate of birth weight less than the 5th percentile was 5.2%, the rate of cesarean delivery was 27.1%, and the rate of perinatal mortality was 0.24%. Velamentous cord insertion was associated with SGA (relative risk [RR] 2.19, 95% CI 1.28-3.74). This persisted after controlling for smoking during pregnancy, diabetes, and hypertension (adjusted odds ratio [aOR] 1.98, 95% CI 1.03-3.84). Velamentous cord insertion was also associated with an increased risk of caesarean birth (RR=1.38, 95% CI=1.08-1,77) and perinatal death (1.87%, RR 8.15, 95% CI 2.02-32.8), a relationship that persisted after controlling for smoking during pregnancy, diabetes, and hypertension (aOR 1.53, 95% CI 1.01-2.32). Marginal cord insertion was not associated with birth weight less than the 5th percentile (RR 1.23, 95% CI 1.00-1.51), cesarean delivery (RR 1.01, 95% CI 0.92-1.10), or perinatal death (RR 1.53, 95% CI 0.62-3.78).

CONCLUSION

Antenatal diagnosis of velamentous placental cord insertion is associated with birth weight less than the 5th percentile.

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.

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.

Role of 2-Dimensional Ultrasound Imaging in Placental and Umbilical Cord Morphometry: Literature and Pictorial Review

Abnormalities of the placenta and umbilical cord have been associated with adverse pregnancy outcomes. Antenatal detection of placental and umbilical cord abnormalities using ultrasound (US) imaging is now gaining popularity with the advancements in obstetric US. This article reviews the use of 2-dimensional obstetric US as a tool to measure and assess placental and umbilical cord morphometry. It highlights the potential role of placental and umbilical cord morphometry as a valuable component of the screening tool for high risk pregnancies and identifies the need for further research to examine its feasibility.

Outcome of pregnancies with marginal umbilical cord insertion

PURPOSE

To evaluate the outcome of labor in cases of marginal umbilical cord insertions.

MATERIAL AND METHODS

This case-control study was carried out between December 1st, 2017 and April 30th, 2018. All singletons with marginal cord insertion (MCI) and three new-borns without MCI were recruited. The main variables studied included gestational age at delivery, occurrence of preeclampsia, intrapartum haemorrhage, mode of delivery, cord insertion, cord length, birth and placenta weights, presence of nuchal cord, Apgar score and admission of the new-born into the neonatal intensive care unit (NICU). Data from both groups were compared. Fisher exact test, t-test and logistic regression were used for comparison. p < .05 was considered statistically significant.

RESULTS

Our prevalence of MCI was 7.2% (85/1181). MCI was significantly associated with pre-eclampsia (aOR 2.94, 95%CI 1.14-7.59), placenta abruption (OR 33.68, 95%CI 9.80-115.76), nuchal cord entanglement (aOR 3.07, 95%CI 1.69-5.59), low birth weight (aOR 3.15, 95%CI 1.05-9.45) and transfer of the newborn to the NICU (OR 4.72, 95%CI 2.46-9.04).

CONCLUSIONS

MCI is associated with increased maternal, fetal and neonatal adverse morbidities. Therefore, pregnancy with MCI should be well followed up. Moreover, the delivery should be conducted in settings where rapid intensive neonatal care can be offered.

Second trimester marginal cord insertion is associated with adverse perinatal outcomes

Objectives: To determine the feasibility in visualizing placental cord insertion (PCI) during second-trimester fetal anatomical survey and the association between marginal cord insertion (MCI) and preterm delivery (PTD) and low birth weight (LBW). Our secondary objectives were to evaluate the association of MCI with adverse composite obstetrical and neonatal outcomes. Methods: A prospective cohort study was performed over a 28-month period. Women with singleton pregnancies presenting for routine anatomical survey between 18 and 22 weeks' gestation were included. PCI site was visualized on 2D grayscale and color Doppler and the shortest distance from the sagittal and transverse planes to the placental edge were recorded. MCI was diagnosed when any of measured distances was ≤2 cm. Correlations were assessed via bivariate chi-squared, independent t-test analyses and Fisher's exact tests. Regression models evaluated associations between MCI and adverse composite outcomes. Results: Three hundred one women were included and PCI was feasible in all cases. The incidence of MCI was 11.3% (n = 34). Baseline characteristics between those with and without MCI were similar, except for story of prior PTD, which was greater among those with MCI (17.65 versus 7.17%, p = .04). MCI was associated with increased likelihood of LBW (RR four; 95%CI, 1.46-10.99) and PTD (RR 3.2; 95%CI, 1.53-6.68); in multivariate analysis, we found associations between MCI and composite adverse obstetrical (RR 2.33; 95%CI, 1.30-4.19) and neonatal (RR 2.46; 95%CI, 1.26-4.81) outcomes. Conclusions: Evaluation of PCI is feasible in all cases. Second-trimester MCI is associated with increased likelihood for LBW, PTD, and composite adverse obstetrical and neonatal outcomes.

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.