Velamentous cord insertion and atypical variable decelerations with no accelerations

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

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

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.

First trimester ultrasound prediction of velamentous cord insertions: a prospective study

INTRODUCTION

The marginal and velamentous cord insertions complicate around 8% of pregnancies and are at higher risk of adverse perinatal outcomes. Their visualisation seems to decrease with advancing gestational age. Our aim was to analyse whether an umbilical cord insertion in the lower third of the uterus during the first trimester could predict abnormal cord insertions later in pregnancy.

METHODS

This was a prospective multicentre study in two hospitals. During the first trimester, the cord insertions were inspected as well as their location (lower third of the uterus or not). Finally, all cord insertions were described at delivery.

RESULTS

During the study period the cord insertion was described in 1620 patients of which 87.7% had a normal cord insertion, 11.9% (n = 192) a low cord insertion, and in 3.8% the insertion could not be situated. We find that 4.7% of those who have a low-lying cord insertion versus 0.7% in the normal cord insertion group during the first trimester will have a velamentous cord insertion subsequently (OR = 6.67; 95% CI = 2.67-16.63).

CONCLUSION

The detection of a low lying umbilical cord insertion during the first-trimester ultrasound can help to predict an abnormal cord insertion at delivery particularly a velamentous cord insertion.

A poor long-term neurological prognosis is associated with abnormal cord insertion in severe growth-restricted fetuses

OBJECTIVE

To clarify and compare if the neurological outcomes of fetal growth restriction (FGR) cases with abnormal cord insertion (CI) are associated with a higher risk of a poor neurological outcome in subjects aged 3 years or less versus those with normal CI.

METHODS

A multicenter retrospective cohort study was conducted among patients with a birth weight lower than the 3rd percentile, based on the standard reference values for Japanese subjects after 22 weeks' gestation, who were treated at a consortium of nine perinatal centers in Japan between June 2005 and March 2011. Patients whose birth weights were less than the 3rd percentile and whose neurological outcomes from birth to 3 years of age could be checked from their medical records were analyzed. The relationship between abnormal CI and neurological outcomes was analyzed. Univariate and multivariate models of multivariate logistic regression were employed to estimate the raw and odds ratio (OR) with 95% confidence intervals comparing marginal (MCI) and velamentous cord insertion (VCI) to normal CI.

RESULTS

Among 365 neonates, 63 cases of MCI and 14 cases of VCI were observed. After excluding 24 cases with neonatal or infant death from the total FGR population, the assessment of the outcomes of the infants aged 3 years or younger showed the following rates of neurological complications: 7.3% (n=25) for cerebral palsy, 8.8% (n=30) for developmental disorders, 16.7% (n=57) for small-for-gestational-age short stature (SGA), 0.6% (n=2) for impaired hearing, 0.9% (n=3) for epilepsy, 1.2% (n=4). The ORs (95% confidence intervals) based on multivariate analysis were as follows: cerebral palsy=10.1 (2.4-41.5) in the VCI group and 4.3 (1.6-11.9) in the MCI group, developmental disorders=6.7 (1.7-26) in the VCI group and 3.9 (1.1-14.2) in the single umbilical artery (SUA) group, 5.1 (1.4-18.7) for birth weight <1000 g and 2.8 (1.2-6.7) for placental weight <200 g.

CONCLUSIONS

The present results indicate that growth-restricted fetuses diagnosed with a birth weight below the 3rd percentile exhibiting abnormal umbilical CI are at a high risk for poor neurological outcomes, including cerebral palsy and/or developmental disorders.

Vaginal delivery in a pregnant woman with cord prolapse, velamentous cord insertion, and fetal vertex presentation: A case report

RATIONALE

We report a rare case of a pregnant woman with cord prolapse, velamentous cord insertion (VCI), and fetal vertex presentation who completed vaginal delivery.

PATIENT CONCERNS

Without having undergone regular antepartum examinations, a 31-year-old pregnant woman, gravida 6, para 4, abortion 1, presented at 37 weeks and 3 days of gestation. She had regular labor pain and bloody show.

DIAGNOSES

Cord prolapse during labor and VCI after delivery.

INTERVENTIONS

Per vaginal examination at 11:20 PM revealed a fully dilated cervix. Thirty minutes later, artificial rupture of the membrane was performed, and an overt prolapsed cord approximately 10-cm long was palpated in the vagina. Fetal heartbeat decelerated to 60 bpm. After fundal pushing for some minutes, a female baby weighing 2130 g was delivered at 11:54 PM with a pediatrician on standby. Apgar scores were 7 (0 minute), 9 (5 minutes), and 10 (10 minutes). The placenta weighed 870 g and was delivered 5 minutes later, and VCI was discovered.

OUTCOMES

Her postpartum course was uncomplicated and both the patient and infant were discharged 3 days later.

LESSONS

A pregnant woman with umbilical prolapse, VCI, and a fetal vertex presentation can successfully deliver a baby through the vagina. Factors contributing to the success of the reported vaginal delivery might have been a small fetus, multipara status, and immediate management.

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

OBJECTIVES

To evaluate perinatal outcomes in singleton and twin pregnancies with pathologically confirmed velamentous cord insertion without vasa previa.

METHODS

This retrospective case-control study included all nonanomalous singleton and twin pregnancies with pathologically confirmed velamentous cord insertion delivered in a single institution between January 1, 2005, and July 1, 2015, and having an ultrasound examination by maternal-fetal medicine. For each case, the next 2 consecutive deliveries matched for gestational age at delivery ± 1 week and, in twins, amnionicity and chorionicity served as controls. Primary outcomes included surgical delivery for a nonreassuring intrapartum fetal heart rate tracing, umbilical arterial cord pH of less than 7.2, 5-minute Apgar score of less than 7, birth weight below the 10th percentile, neonatal intensive care unit admission, fetal or neonatal death, and cord avulsion necessitating manual placental extraction.

RESULTS

Outcomes were available for 53 singletons with 103 matched controls and 33 twin pregnancies with 65 matched controls. In singletons, velamentous cord insertion was associated with cord pH of less than 7.2 (odds ratio [OR] 3.5; 95% confidence interval [CI], 1.1-11.2; P = .039), 5-minute Apgar score of less than 7 (OR, 5.3; 95% CI, 0.99-28.1; P = .045), and cord avulsion requiring manual placental extraction (7.5% versus 0%; P = .012). Associations were suggested with increased surgical delivery for a nonreassuring intrapartum fetal heart rate tracing (OR, 2.4; 95% CI, 0.9-6.9; P = .14), birth weight below the 10th percentile (OR, 2.1; 95% CI, 0.8-5.9; P = .21), and fetal or neonatal death (3.8% versus 0%; P = .11). Velamentous cord insertions were also associated with placental abruption in singletons (7.5% versus 0%; P = .013). Among twins, velamentous cord insertion was associated with fetal or neonatal death (9.1% versus 0%; P = .036).

CONCLUSIONS

Isolated confirmed velamentous cord insertion is associated with adverse perinatal outcomes in singleton and twin gestations.

Velamentous cord insertion in a singleton pregnancy: an obscure cause of emergency cesarean-a case report

Approximately 2% of low-risk pregnant women still require an emergency Cesarean section after the onset of labor. Because it is likely that half of these cases are associated with placental and umbilical cord abnormalities, it is thought that prenatal detection of such abnormalities would reduce the number of emergency cesarean sections in low-risk women. Velamentous cord insertion is an abnormal cord insertion in which the umbilical vessels diverge as they traverse between the amnion and chorion before reaching the placenta. With a reported incidence of 1% in singleton pregnancies, it has been associated with several obstetric complications. This condition has been diagnosed by ultrasonography with a sensitivity of 67% and specificity of 100% in the second trimester. The present case highlights the importance of the systematic assessment of the placental cord insertion site at routine obstetric ultrasound and the potential of identifying pregnancies with velamentous insertion and, therefore, those at risk for obstetric complications.

Umbilical cord insertion site in early gestation and development of placenta

AIM

To study the relation of umbilical cord insertion (CI) site in early gestation and placental development from the chorion villosum.

METHODS

We ultrasonically measured the distance between the internal cervical Os and the CI site (CID), the distance between the internal cervical Os and lower placenta edge (PLD), and placental thickness at early (10-12 weeks) and mid-gestation (18-20 weeks).

RESULTS

CID in early gestation (CID-Early) correlated with CID in mid-gestation (r(2)=0.171; P<0.01). CID-Early correlated with PLD in mid-gestation (r(2)=0.093; P<0.01). Thickness of chorion villosum or placenta in early gestation did not correlate with that at mid-gestation. Increasing thickness of placenta was significantly higher in long CID-Early (> or =20 mm) cases than short cases (<20 mm) (P<0.05).

CONCLUSIONS

The process of placental development and the placental location are affected by CI location at early gestation, and suggests that this process might be affected by poor blood supply from the low uterine segment when CI site is close to the internal cervical Os.

Velamentous Cord Insertion: Significance of Prenatal Detection to Predict Perinatal Complications

In the maternal and child health statistics of Japan for 2003, perinatal deaths were most frequent in pregnant women with abnormalities of the placenta, umbilical cord, and fetal membrane. Despite advances in perinatal medicine, approximately 2% of low-risk pregnant women still require an emergency cesarean section after the onset of labor. Because it is likely that half of these cases are associated with placental and umbilical cord abnormalities, it is thought that prenatal detection of such abnormalities would reduce the number of emergency cesarean sections in low-risk women. In our previous studies, some abnormalities of the placenta and umbilical cord were associated with abnormalities of cord insertion. Furthermore, we reported that prenatal detection of velamentous cord insertion (VCI) reduced the number of emergency cesarean sections in low-risk women. In this review, we describe the prenatal detection of abnormalities of umbilical cord insertion and the management of VCI based on our current clinical data.