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Obstetrics and Gynecology Sep 2015Placental disorders such as placenta previa, placenta accreta, and vasa previa are all associated with vaginal bleeding in the second half of pregnancy. They are also... (Comparative Study)
Comparative Study Review
Placental disorders such as placenta previa, placenta accreta, and vasa previa are all associated with vaginal bleeding in the second half of pregnancy. They are also important causes of serious fetal and maternal morbidity and even mortality. Moreover, the rates of previa and accreta are increasing, probably as a result of increasing rates of cesarean delivery, maternal age, and assisted reproductive technology. The routine use of obstetric ultrasonography as well as improving ultrasonographic technology allows for the antenatal diagnosis of these conditions. In turn, antenatal diagnosis facilitates optimal obstetric management. This review emphasizes an evidence-based approach to the clinical management of pregnancies with these conditions as well as highlights important knowledge gaps.
Topics: Adult; Cesarean Section; Evidence-Based Medicine; Female; Humans; Hysterectomy; Infant, Newborn; Placenta Accreta; Placenta Previa; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Pregnancy Trimester, Second; Risk Assessment; Severity of Illness Index; Treatment Outcome; Ultrasonography, Prenatal; Uterine Hemorrhage; Vasa Previa
PubMed: 26244528
DOI: 10.1097/AOG.0000000000001005 -
Obstetrics and Gynecology Sep 2023Vasa previa refers to unprotected fetal vessels running through the membranes over the cervix. Until recently, this condition was associated with an exceedingly high...
Vasa previa refers to unprotected fetal vessels running through the membranes over the cervix. Until recently, this condition was associated with an exceedingly high perinatal mortality rate attributable to fetal exsanguination when the membranes ruptured. However, ultrasonography has made it possible to diagnose the condition prenatally, allowing cesarean delivery before labor or rupture of the membranes. Several recent studies have indicated excellent outcomes with prenatally diagnosed vasa previa. However, outcomes continue to be dismal when vasa previa is undiagnosed before labor. Risk factors for vasa previa include second-trimester placenta previa and low-lying placentas, velamentous cord insertion, placentas with accessory lobes, in vitro fertilization, and multifetal gestations. Recognition of individuals who are at risk and screening them will greatly decrease the mortality rate from this condition. Because of the relative rarity of vasa previa, there are no randomized controlled trials to guide management. Therefore, recommendations on the diagnosis and management of vasa previa are based largely on cohort studies and expert opinion. This Clinical Expert Series review addresses the epidemiology, pathophysiology, natural history, diagnosis and management of vasa previa, as well as innovative treatments for the condition.
Topics: Female; Pregnancy; Humans; Vasa Previa; Cesarean Section; Fertilization in Vitro; Fetus; Labor, Obstetric
PubMed: 37590981
DOI: 10.1097/AOG.0000000000005287 -
Obstetrics and Gynecology Mar 2020Umbilical cord abnormalities are commonly cited as a cause of stillbirth, but details regarding these stillbirths are rare. Our objective was to characterize stillbirths...
OBJECTIVE
Umbilical cord abnormalities are commonly cited as a cause of stillbirth, but details regarding these stillbirths are rare. Our objective was to characterize stillbirths associated with umbilical cord abnormalities using rigorous criteria and to examine associated risk factors.
METHODS
The Stillbirth Collaborative Research Network conducted a case-control study of stillbirth and live births from 2006 to 2008. We analyzed stillbirths that underwent complete fetal and placental evaluations and cause of death analysis using the INCODE (Initial Causes of Fetal Death) classification system. Umbilical cord abnormality was defined as cord entrapment (defined as nuchal, body, shoulder cord accompanied by evidence of cord occlusion on pathologic examination); knots, torsions, or strictures with thrombi, or other obstruction by pathologic examination; cord prolapse; vasa previa; and compromised fetal microcirculation, which is defined as a histopathologic finding that represents objective evidence of vascular obstruction and can be used to indirectly confirm umbilical cord abnormalities when suspected as a cause for stillbirth. We compared demographic and clinical factors between women with stillbirths associated with umbilical cord abnormalities and those associated with other causes, as well as with live births. Secondarily, we analyzed the subset of pregnancies with a low umbilical cord index.
RESULTS
Of 496 stillbirths with complete cause of death analysis by INCODE, 94 (19%, 95% CI 16-23%) were associated with umbilical cord abnormality. Forty-five (48%) had compromised fetal microcirculation, 27 (29%) had cord entrapment, 26 (27%) knots, torsions, or stricture, and five (5%) had cord prolapse. No cases of vasa previa occurred. With few exceptions, maternal characteristics were similar between umbilical cord abnormality stillbirths and non-umbilical cord abnormality stillbirths and between umbilical cord abnormality stillbirths and live births, including among a subanalysis of those with hypo-coiled umbilical cords.
CONCLUSION
Umbilical cord abnormalities are an important risk factor for stillbirth, accounting for 19% of cases, even when using rigorous criteria. Few specific maternal and clinical characteristics were associated with risk.
Topics: Adult; Case-Control Studies; Female; Humans; Pregnancy; Stillbirth; Umbilical Cord; United States; Young Adult
PubMed: 32028503
DOI: 10.1097/AOG.0000000000003676 -
The New England Journal of Medicine Jan 2019
Topics: Adult; Female; Fetus; Humans; Placenta; Pregnancy; Ultrasonography, Doppler, Color; Ultrasonography, Prenatal; Umbilical Cord; Vasa Previa
PubMed: 30650329
DOI: 10.1056/NEJMicm1808778 -
Seminars in Perinatology Feb 2024Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been...
Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been identified and include obstetrical complications, placental abnormalities, fetal malformations, infections, and medical complications in pregnancy. Placental abnormalities such as placental abruption, chorioangioma, vasa previa, and umbilical cord abnormalities have been identified as causes of death for a significant proportion of stillbirths. In the absence of placental abnormalities, the gross and histologic changes in the placenta in stillbirth are found when secondary to other etiologies. Here we describe both gross and histologic changes of the placenta that are associated with stillbirth.
Topics: Pregnancy; Female; Humans; Stillbirth; Placenta; Placenta Diseases; Abruptio Placentae; Public Health
PubMed: 38199875
DOI: 10.1016/j.semperi.2023.151871 -
American Journal of Obstetrics &... Aug 2020To systematically review published literature and calculate the prevalence of vasa previa and its known risk factors. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To systematically review published literature and calculate the prevalence of vasa previa and its known risk factors.
MATERIALS AND METHODS
MEDLINE, Embase, the Cochrane Library, PubMed (non-MEDLINE and in process), and www.clinicaltrials.gov were searched from inception to March 2018 using indexing terms "vasa previa," "placenta previa," "low lying placenta," "succenturiate lobe," "bilobate placenta," "bilobed placenta," and "velamentous insertion." All original research studies reporting on 5 or more pregnancies with vasa previa were included. The search was limited to studies on human data and those published in the English language. Two reviewers independently screened titles and abstracts, completed data extraction, and assessed reporting quality using the Study Quality Assessment Tool for Case Series Studies of the National Heart, Lung, and Blood Institute. Disagreements were discussed and resolved at each step of the process.
RESULTS
We included 21 studies that reported 428 pregnancies with vasa previa of 1,027,918 deliveries (0.46 cases of vasa previa per 1000 deliveries). These studies fared well on risk of bias assessment using the Study Quality Assessment Tool for Case Series Studies of the National Heart, Lung, and Blood Institute. The prevalence and 95% confidence intervals of known risk factors for vasa previa included a low-lying placenta (61.5%, 53.0%-70.0%), velamentous cord insertion (52.2%, 39.6%-64.7%), bilobed or succenturiate lobed placenta (33.3%, 20.9%-45.7%), use of in vitro fertilization (26.4%, 16.0%-36.8%), and multiple gestation (8.92%, 5.33%-12.5%).
CONCLUSION
Vasa previa affects 0.46 cases per 1000 pregnancies. Given the high prevalence of prenatally detectable risk factors in affected pregnancies, the cost-effectiveness of screening strategies for vasa previa either in isolation, using a risk factor-based approach, or universally, in tandem with cervical-length screening using transvaginal ultrasound, should be revisited.
Topics: Female; Humans; Placenta; Placenta Previa; Pregnancy; Risk Factors; Ultrasonography, Prenatal; Vasa Previa
PubMed: 33345868
DOI: 10.1016/j.ajogmf.2020.100117 -
Obstetrics and Gynecology Clinics of... Mar 2020Primary disorders of placental implantation have immediate consequences for the outcome of a pregnancy. These disorders have been known to clinical science for more than... (Review)
Review
Primary disorders of placental implantation have immediate consequences for the outcome of a pregnancy. These disorders have been known to clinical science for more than a century, but have been relatively rare. Recent epidemiologic obstetric data have indicated that the rise in their incidence over the last 2 decades has been iatrogenic in origin. In particular, the rising numbers of pregnancies resulting from in vitro fertilization (IVF) and the increased use of caesarean section for delivery have been associated with higher frequencies of previa implantation, accreta placentation, abnormal placental shapes, and velamentous cord insertion. These disorders often occur together.
Topics: Cesarean Section; Female; Humans; Placenta Accreta; Placenta Previa; Pregnancy; Risk Factors; Ultrasonography, Prenatal; Vasa Previa
PubMed: 32008663
DOI: 10.1016/j.ogc.2019.10.002 -
Current Opinion in Obstetrics &... Dec 2018Vasa previa is a rare disorder of placentation associated with a high rate of perinatal morbidity and mortality when undetected before delivery. We have evaluated the...
PURPOSE OF REVIEW
Vasa previa is a rare disorder of placentation associated with a high rate of perinatal morbidity and mortality when undetected before delivery. We have evaluated the recent evidence for prenatal diagnosis and management of vasa previa.
RECENT FINDINGS
Around 85% of cases of vasa previa have one or more identifiable risk factors including in-vitro fertilization, multiple gestations, bilobed, succenturiate or low-lying placentas, and velamentous cord insertion. The development of standardized prenatal targeted scanning protocols may improve perinatal outcomes. There is no clear consensus on the optimal surveillance strategy including the need for hospitalization, timing of corticosteroids administration and the value of transvaginal cervical length measurements. Outpatient management is possible if there is no evidence of cervical shortening on ultrasound and there are no symptoms of bleeding or uterine contractions. Recent national guidelines and expert reviews have recommended scheduled cesarean section of all asymptomatic women presenting with vasa previa between 34 and 36 weeks' gestation.
SUMMARY
Prenatal diagnosis of vasa previa is pivotal to prevent intrapartum fetal death. Although there is insufficient evidence to support the universal mid-gestation ultrasound screening for vasa previa, recent evidence indicates the need for standardized prenatal targeted screening protocols of pregnancies at high-risk of vasa previa.
Topics: Adrenal Cortex Hormones; Adult; Cervical Length Measurement; Cesarean Section; Early Diagnosis; Female; Gestational Age; Humans; Practice Guidelines as Topic; Pregnancy; Pregnancy Complications; Prenatal Diagnosis; Risk Factors; Ultrasonography, Prenatal; Vasa Previa
PubMed: 30102606
DOI: 10.1097/GCO.0000000000000478 -
American Journal of Obstetrics and... Dec 2019
Topics: Female; Humans; Pregnancy; Retrospective Studies; Ultrasonography, Prenatal; Vasa Previa
PubMed: 31787156
DOI: 10.1016/j.ajog.2019.08.034 -
The Journal of Obstetrics and... Nov 2023To describe our individualized management protocol for women with an antenatal diagnosis of vasa previa (VP) and to report maternal and neonatal outcomes in patients...
OBJECTIVE
To describe our individualized management protocol for women with an antenatal diagnosis of vasa previa (VP) and to report maternal and neonatal outcomes in patients managed according to our protocol.
METHODS
A retrospective study of prospectively collected data of antenatally diagnosed VP managed at our hospital between 2014 and 2021. Obstetric and neonatal outcomes were reviewed and analyzed.
RESULTS
Fourteen cases of antenatally diagnosed VP in 5150 total deliveries were analyzed (0.3%) Five cases (36%) of VP were diagnosed during the routine fetal morphological ultrasound screening, and nine cases (64%) were referred to our hospital due to perinatal complications. There were nine cases that required hospitalization (due to fetal growth restriction [FGR] [1], preterm labor [3], patients' request [5]). The other five were asymptomatic. Eight patients were delivered by scheduled cesarean section at around 36 weeks and only three neonates were admitted to NICU with transient tachypnea of newborn. However, six patients required CS before the scheduled dates because of other complications (preterm labor [3], abnormal cardiotocogram patterns [1], FGR [1] and twin pregnancy [1]). Four neonates born by CS before their scheduled dates were admitted to NICU. No cases required prolonged hospitalization and there were no serious neonatal complications.
CONCLUSION
Individualized management may lead to favorable outcomes with VP. Outpatient management may be considered in patients without risk factors. However, maternal hospitalization and earlier scheduled CS should be considered in symptomatic patients or those at risk for preterm delivery.
Topics: Infant, Newborn; Pregnancy; Female; Humans; Vasa Previa; Retrospective Studies; Cesarean Section; Prenatal Diagnosis; Ultrasonography, Prenatal; Premature Birth
PubMed: 37621145
DOI: 10.1111/jog.15775