Impact of Universal Vasa Previa Screening With Color Doppler During the OB Ultrasound Anatomy Scan.

OBJECTIVES: Our institution introduced universal vasa previa (VP) screening utilizing transabdominal ultrasound with color Doppler for all pregnancies at the second trimester anatomy scan. Our study sought to describe the clinical impact of this intervention. METHODS: Radiology records from the 12 months pre- and post-intervention were queried for "vasa previa." Records included for analysis were those with a first-time diagnosis or discussion of VP at the anatomy scan. Cases were categorized by outcome: (Group 1) True VP, with subgroups A, unresolved by time of delivery and B, resolved by delivery; (Group 2) False positives; (Group 3) Possible VP without definitive diagnosis; and (Group 4) VP ruled out, for example, "no features of VP." Group size was expressed as a percentage of total anatomy scans during pre- or post-intervention periods respectively. Absolute and relative percent change were calculated for each group. RESULTS: In the pre-intervention period, 1 case (0.36% of total scans) was categorized in Group 1A, 1 case (0.36%) in Group 3, and 7 cases (2.53%) in Group 4. In the post-intervention period, 2 cases (0.30%) were in Group 1A, 4 cases (0.61%) in Group 1B, 2 cases (0.30%) in Group 2, 1 case (0.15%) in Group 3, and 7 cases (1.06%) in Group 4. There was a +153% relative change in true positives, from 0.36 to 0.91%. CONCLUSIONS: Universal color Doppler screening may have increased detection (sensitivity) while simultaneously increasing false positives (decreased specificity). While decreasing sensitivity is not ideal, this is acceptable given the potential catastrophic outcome of a missed VP.

Impact of velamentous cord insertion on perinatal outcomes: a systematic review and meta-analysis.

OBJECTIVE: Velamentous cord insertion may be identified prenatally, but the clinical implications of this diagnosis remain controversial. This meta-analysis aimed to quantitatively summarize current data on the association of velamentous cord insertion and adverse perinatal outcomes. DATA SOURCES: A systematic search was performed in MEDLINE, Scopus, and the Cochrane Library from inception until May 22, 2022 to identify eligible studies. STUDY ELIGIBILITY CRITERIA: Observational studies including singleton pregnancies with velamentous cord insertion, either prenatally or postnatally identified, and comparing them with those with central/eccentric cord insertion were considered eligible. METHODS: The quality of the studies was assessed with the Newcastle-Ottawa scale and the risk of bias with the Quality In Prognosis Studies (QUIPS) tool. The main outcome was small-for-gestational-age neonates. Heterogeneity of the studies was evaluated using a Q test and an I2 index. Analyses were performed using a random-effects model, with outcome data reported as relative risk or mean difference with 95% confidence interval. RESULTS: In total, 9 cohort and 2 case-control studies, of which 4 had prenatal and 7 had postnatal velamentous cord insertion diagnosis, were included. The overall prevalence of velamentous cord insertion was estimated to be 1.4% among singleton pregnancies. Compared with the central/eccentric cord insertion control group, pregnancies with velamentous cord insertion were at higher risk of several adverse perinatal outcomes, namely small-for-gestational-age neonates (relative risk, 1.93; 95% confidence interval, 1.54-2.41), preeclampsia (relative risk, 1.85; 95% confidence interval, 1.01-3.39), pregnancy-induced hypertension (relative risk, 1.58; 95% confidence interval, 1.46-1.70), stillbirth (relative risk, 4.12; 95% confidence interval, 1.92-8.87), placental abruption (relative risk, 2.94; 95% confidence interval, 1.72-5.03), preterm delivery (relative risk, 2.14; 95% confidence interval, 1.73-2.65), emergency cesarean delivery (relative risk, 2.03; 95% confidence interval, 1.22-3.38), 1-minute Apgar score <7 (relative risk, 1.53; 95% confidence interval, 1.14-2.05), 5-minute Apgar score <7 (relative risk, 1.97; 95% confidence interval, 1.43-2.71), and neonatal intensive care unit admission (relative risk, 1.63; 95% confidence interval, 1.32-2.02). In a subgroup analysis, prenatally diagnosed velamentous cord insertion was associated with small-for-gestational-age neonates (relative risk, 1.66; 95% confidence interval, 1.19-2.32), stillbirth (relative risk, 4.78; 95% confidence interval, 1.42-16.08), and preterm delivery (relative risk, 2.69; 95% confidence interval, 2.01-3.60). In a sensitivity analysis of studies excluding cases with vasa previa, velamentous cord insertion was associated with an increased risk of small-for-gestational-age neonates (relative risk, 2.69; 95% confidence interval, 1.73-4.17), pregnancy-induced hypertension (relative risk, 1.94; 95% confidence interval, 1.24-3.01), and stillbirth (relative risk, 9.42; 95% confidence interval, 3.19-27.76), but not preterm delivery (relative risk, 1.92; 95% confidence interval, 0.82-4.54). CONCLUSION: Velamentous cord insertion is associated with several adverse perinatal outcomes, including stillbirth, and these associations persist when only prenatally diagnosed cases are considered and when vasa previa cases are excluded. According to these findings, the exact pathophysiology should be further investigated and an effective prenatal monitoring plan should be developed.

Vasa previa: when antenatal diagnosis can change fetal prognosis.

OBJECTIVES: Evaluate ultrasound diagnostic accuracy, maternal-fetal characteristics and outcomes in case of vasa previa diagnosed antenatally, postnatally or with spontaneous resolution before delivery. METHODS: Monocentric retrospective study enrolling women with antenatal or postnatal diagnosis of vasa previa at Sant'Anna Hospital in Turin from 2007 to 2018. Vasa previa were defined as fetal vessels that lay 2 cm within the uterine internal os using 2D and Color Doppler transvaginal ultrasound. Diagnosis was confirmed at delivery and on histopathological exam. Vasa previa with spontaneous resolutions were defined as fetal vessels that migrate >2 cm from uterine internal os during scheduled ultrasound follow-ups in pregnancy. RESULTS: We enrolled 29 patients (incidence of 0.03%). Ultrasound antenatally diagnosed 25 vasa previa (five had a spontaneous resolution) while four were diagnosed postnatally, with an overall sensitivity of 96.2%, specificity of 100%, positive predictive value of 96.2%, and negative predictive value of 100%. Early gestational age at diagnosis is significally associate with spontaneously resolution (p 0.023; aOR 1.63; 95% IC 1.18-2.89). Nearly 93% of our patient had a risk factor for vasa previa: placenta previa at second trimester or low-lying placenta, bilobated placenta, succenturiate cotyledon, velametous cord insertion or assisted reproduction technologies. CONCLUSIONS: Maternal and fetal outcomes in case of vasa previa antenatally diagnosed are significally improved. Our data support the evaluation of umbilical cord insertion during routine second trimester ultrasound and a targeted screening for vasa previa in women with risk factor: it allows identification of fetus at high risk, reducing fetal mortality in otherwise healthy newborns.

Vasa previa: Perinatal outcomes in singleton and multiple pregnancies.

Vasa previa (VP) is a rare and life-threatening condition for the fetus. It is associated with increased perinatal mortality rates. The current study sought to retrospectively analyze the perinatal outcomes of VP in singleton and multiple pregnancies between January 1, 2013 and December 31, 2019 at a tertiary hospital in west China. One hundred and fifty-seven cases of VP were identified, including 131 singletons, 23 twins and 3 triplets. VP in 20 cases was diagnosed at delivery. There were 183 live births. Neonatal mortality was significantly higher in cases with no prenatal diagnosis (9.7% vs. 1.3%, p = 0.035). There was a significantly higher rate of NICU admission, premature infant and neonatal pneumonia in cases with prenatal diagnosis (p < 0.05). Among twin pregnancies with VP as a prenatal diagnosis, there were significantly earlier gestational age at admission (31.1 vs. 34.1 weeks, p = 0.000) and delivery age (33.4 vs. 35.3 weeks, p = 0.000) than those among singleton pregnancies. The neonatal mortality in twins with prenatal diagnosis was significantly higher than that in singletons (0% vs. 6.9%, p = 0.037). Early hospitalization of VP in the third trimester may be reasonable. The data suggest that the timing of elective delivery at 34-36 weeks in singletons and 32-34 weeks in twins may be suitable. It should be emphasized to make corresponding optimal delivery time according to individual differences for the women, especially in twin pregnancy.

Perinatal outcome of pregnancies with prenatal diagnosis of vasa previa: systematic review and meta-analysis.

OBJECTIVES: To derive accurate estimates of perinatal survival in pregnancies with and without a prenatal diagnosis of vasa previa based on a systematic review of the literature and meta-analysis. METHODS: A search of MEDLINE, EMBASE and The Cochrane Library was performed to review relevant citations reporting on the perinatal outcomes of pregnancies with vasa previa. We included prospective and retrospective cohort and population studies that provided data on pregnancies with a prenatal diagnosis of vasa previa or cases diagnosed at birth or following postnatal placental examination. Meta-analysis using a random-effects model was performed to derive weighted pooled estimates of perinatal survival (excluding stillbirths and neonatal deaths) and intact perinatal survival (additionally excluding hypoxic morbidity). Incidence rate difference (IRD) meta-analysis was used to estimate the significance of differences in pooled proportions between cases of vasa previa with and those without a prenatal diagnosis. Heterogeneity between studies was estimated using Cochran's Q and the I2 statistic. RESULTS: We included 21 studies reporting on the perinatal outcomes of 683 pregnancies with a prenatal diagnosis of vasa previa. There were three stillbirths (1.01% (95% CI, 0.40-1.87%)), five neonatal deaths (1.19% (95% CI, 0.52-2.12%)) and 675 surviving neonates, resulting in a pooled estimate for perinatal survival of 98.6% (95% CI, 97.6-99.3%). Based on seven studies that included cases of vasa previa with and without a prenatal diagnosis, the pooled perinatal survival in pregnancies without a prenatal diagnosis (61/118) was 72.1% (95% CI, 50.6-89.4%) vs 98.6% (95% CI, 96.7-99.7%) in cases with a prenatal diagnosis (224/226). Therefore, the risk of perinatal death was 25-fold higher when a diagnosis of vasa previa was not made antenatally, compared with when it was (odds ratio (OR), 25.39 (95% CI, 7.93-81.31); P < 0.0001). Similarly, the risk of hypoxic morbidity was increased 50-fold in cases with vasa previa without a prenatal diagnosis compared with those with a prenatal diagnosis (36/61 vs 5/224; OR, 50.09 (95% CI, 17.33-144.79)). The intact perinatal survival rate in cases of vasa previa without a prenatal diagnosis was significantly lower than in those with a prenatal diagnosis (28.1% (95% CI, 14.1-44.7%) vs 96.7% (95% CI, 93.6-98.8%)) (IRD, 73.4% (95% CI, 53.9-92.7%); Z = -7.4066, P < 0.001). CONCLUSIONS: Prenatal diagnosis of vasa previa is associated with a high rate of perinatal survival, whereas lack of an antenatal diagnosis significantly increases the risk of perinatal death and hypoxic morbidity. Further research should be undertaken to investigate strategies for incorporating prenatal screening for vasa previa into routine clinical practice. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Clinical features of velamentous umbilical cord insertion and vasa previa: A retrospective analysis based on 501 cases.

ABSTRACT: To identify the risk factors associated with velamentous cord insertion (VCI) and investigate the association between adverse pregnancy outcomes and VCI in singleton pregnancies and those with vasa previa.A total of 59,976 single cases admitted from Qinhuangdao Maternal and Child Health Hospital and Qinhuangdao Beidaihe Hospital from January 2004 to January 2014 were included in this study. We retrospectively analyzed the perinatal complications, neonatal complications, and the clinical features, as well as the Color Doppler ultrasonography findings of the velamentous placenta and placenta previa.We reviewed the clinical data of 59,976 women with singleton pregnancies delivered in Qinhuangdao Maternal and Child Health Hospital and Qinhuangdao Beidaihe Hospital from January 2004 to January 2014. Risk factors and the risks of adverse pregnancy outcomes including admission to a neonatal unit, fetal death, preterm delivery, low birth weight of <2500 g, the infant being small for its gestation age, low Apgar scores (<7) at 1 and 5 minute were evaluated separately among women with and without VCI by means of logistic regression analyses.The prevalence of velamentous umbilical cord insertion was 0.84%, and the prevalence of vasa previa was 0.0017%. The independent risk factors for VCI were nulliparity, obesity, fertility problems, placenta previa, and maternal smoking. VCI was associated with a 1.83-, 2.58-, 3.62-, and 1.41-fold increase in the risk of retention in the neonatal unit, preterm delivery (<37 gestation weeks), low birth weight, and small-for-gestational age, compared to pregnancies involving normal cord insertion. Of the women with VCI, 16.1% underwent emergency cesarean section compared to 8.9% (P < .001) of women without VCI.The prevalence of VCI was 0.84% in singletons. The results suggest that VCI is a moderate risk condition resulted in increased risks of prematurity and impairment of fetal growth.

Vasa Previa: A Case Report.

Vasa previa is a rare but serious medical condition characterized by a velamentous insertion of fetal blood vessels onto the placenta, which places those vessels at high risk of rupturing with rupturing of the membranes. Often vasa previa goes undetected until fetal compromise ensues following rupture of membranes. A recent case report of a 25-year-old pre-eclamptic female demonstrates the emergent and fatal nature of undiagnosed vasa previa.

Core outcome set for studies on pregnant women with vasa previa (COVasP): a study protocol.

INTRODUCTION: Vasa previa is a condition where fetal blood vessels run unprotected in the membranes, outside the umbilical cord, and cross the internal opening of the cervix. During rupture of membranes, these vessels can rupture and put the baby at serious risk of severe blood loss and death. Numerous studies are being conducted to improve diagnostic modalities and establish clear management plans to improve pregnancy outcomes. However, the lack of a standardised set of outcomes for studies on vasa previa makes it difficult to compare study findings and draw meaningful conclusions. Through this project, we will be developing a core outcome set for studies on pregnant women with vasa previa (COVasP). METHODS AND ANALYSIS: The development of COVasP will involve five steps. The first will be a systematic review, in which we will generate a long list of outcomes based on published studies in pregnancies complicated with vasa previa. The second will involve in-depth interviews with current and former patients, their family members and healthcare providers who care for these patients. This will be followed by a two-round Delphi survey, which will aim to narrow down the long list of outcomes into those considered important by four groups of 'stakeholders': (1) patients, family members and patient advocates/representatives, (2) healthcare providers, (3) researchers, epidemiologists and methodologists and (4) other stakeholders directly or indirectly involved in the management of these pregnancies such as administrators, guideline developers and policymakers. The fourth step will involve a face-to-face consensus meeting using a nominal group approach to establish a finalised core outcome set. The final step will involve measuring and defining the identified outcomes using a combination of systematic reviews and Delphi surveys. ETHICS AND DISSEMINATION: This study as well as consent forms for stakeholder participation have received approval from the Mount Sinai Hospital Research Ethics Board (REB number 18-0173-E) on 05 September 2018 and the Human Research Ethics Committee at The University of Technology Sydney, Australia on 30 July 2019 (UTS HREC reference number ETH19-3718). All progress will be documented on the international prospective register of systematic reviews and Core Outcome Measures in Effectiveness Trials databases. REGISTRATION DETAILS: http://www.comet-initiative.org/studies/details/1117.

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.

Placental Implantation Disorders.

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.

[Velamentous cord insertion associated with vasa praevia]. / Le cas clinique du mois. Insertion vélamenteuse du cordon ombilical associée à un vasa praevia.

Velamentous cord insertion is a rare placental abnormality, that may be associated with vasa praevia, i.e. the presence of an umbilical vessel near the internal cervical orifice. In case of spontaneous rupture of the membranes, there is a major risk of fetal haemorrhage, which is often lethal for the unborn baby. The challenge of care is based on the prenatal diagnosis during the 2nd trimester ultrasound. In case a vasa praevia is confirmed during the 3rd trimester, elective caesarean section should be carried out prior to the onset of labour, between 34 and 36 weeks of pregnancy. Corticosteroid treatment for fetal lung maturation is recommended at 32 weeks of gestation because of the increased risk of preterm delivery. Velamentous cord insertion may be associated with other adverse pregnancy outcomes such as intrauterine growth restriction, death in utero, placental abnormalities.

L'insertion vélamenteuse du cordon ombilical est une anomalie placentaire rare, pouvant être associée à un vasa praevia, c'est-à-dire la présence d'un vaisseau ombilical en regard de l'orifice interne du col utérin. En cas de rupture spontanée des membranes, le risque d'hémorragie fœtale est majeur et, le plus souvent, létal pour l'enfant à naître. Le défi de la prise en charge est le diagnostic anténatal à l'échographie du 2ème trimestre. En cas de vasa praevia confirmé lors du 3ème trimestre, une césarienne doit être programmée avant la mise en travail spontanée, aux alentours de 34-36 semaines d'aménorrhée. Une cure de maturation pulmonaire par corticostéroïdes est recommandée à 32 semaines d'aménorrhée en raison du risque accru de prématurité. L'insertion vélamenteuse du cordon peut être associée à d'autres complications périnatales telles qu'un retard de croissance intra-utérin, une mort fœtale in utero, des anomalies placentaires.

Case report: a rapid review approach used by the UK National Screening Committee to inform recommendations on general population screening for vasa praevia.

BACKGROUND: The UK National Screening Committee (UK NSC) reviews evidence about existing or potential population screening programmes using rapid review products called evidence summaries. We provide a case report as an example of how rapid reviews are developed within the UK NSC's process, consider how the quality of rapid reviews should be assessed and ask whether the rapid review was an appropriate tool to inform the UK NSC's decision-making process. METHODS: We present the rapid review approach taken by the commissioner and the reviewers to develop an evidence summary for vasa praevia (VP), which the UK NSC reappraised as part of its 3-yearly cycle for conditions where screening is currently not recommended. We apply the AMSTAR 2 quality appraisal checklist for systematic reviews, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and a published checklist of items to consider with a rapid review approach. As UK NSC evidence summaries do not include meta-analyses, any related AMSTAR 2 or PRISMA checklist items were considered inapplicable. RESULTS: The evidence summary was available within the required timelines and highlighted little change from the previous review in terms of key evidence gaps relating to the epidemiology of VP, the screening test and the management pathway. Therefore, the UK NSC concluded that there was insufficient evidence to support a change in its previous recommendation against screening. The evidence summary scored moderately against the applicable AMSTAR 2 and PRISMA checklist items. Against the published checklist of items to consider with a rapid review approach, the evidence summary performed well. CONCLUSIONS: In this case report, the use of a rapid review as part of the UK NSC's process enabled a pragmatic approach to assessing the overall volume, quality and direction of literature on key questions relating to the viability of a population screening programme for VP. Based on our assessments of this single evidence summary, systematic review quality appraisal tools may undervalue rapid reviews. The validity of the methods used in this case report, as well as the wider generalisability of our insights relating to rapid review practice, reporting and quality assessment, requires analysis of a larger sample of rapid reviews.

Diagnosis and Management of Vasa Previa: A Comparison of 4 National Guidelines.

IMPORTANCE: Vasa previa represents an uncommon and life-threatening condition for the fetus. The prenatal identification of the condition may improve the outcome. OBJECTIVE: The aim of this study was to synthesize and compare published evidence of 4 national guidelines on diagnosis and management of vasa previa. EVIDENCE ACQUISITION: A descriptive review of 4 recently published national guidelines on vasa previa was conducted: Royal College of Obstetricians and Gynaecologists on "Vasa Praevia: Diagnosis and Management," Society for Maternal-Fetal Medicine on "Diagnosis and Management of Vasa Previa," Society of Obstetricians and Gynaecologists of Canada on "Guidelines for the Management of Vasa Previa," and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists on "Vasa Praevia." These guidelines were compared regarding recommendations on diagnosis and management, while the quality of evidence was also reviewed based on each method of reporting. RESULTS: There were many similar recommendations in the compared guidelines regarding the diagnosis and management of vasa previa. Early prenatal diagnosis using ultrasound and color Doppler imaging, hospitalization or management as outpatients, and cesarean delivery in a tertiary center with experienced clinicians are the main recommendations. CONCLUSIONS: Evidence-based guidelines may increase the awareness of the diagnosis and management of vasa previa among health care professionals and lead to more favorable perinatal outcomes.

Is scanning for vasa previa important for singleton pregnancies that started as multiple conceptions?

OBJECTIVES: Vasa previa (VP) is a congenital placentation disorder in which fetal vessels run across the internal os of the cervix under the fetal presentation. This rare condition is associated with a high rate of perinatal morbidity and mortality when undetected before delivery. Roughly 85% of all cases of VP can be associated with one or more identifiable risk factors including in-vitro fertilization (IVF), multiple gestations, bilobed, succenturiate or low-lying placentas, and velamentous cord insertion (VCI). Recent evidence indicates the need for standardized prenatal targeted scanning protocols of pregnancies at risk of VP. The present study reports on pregnancies that began with multiple gestations but ended with a single fetus diagnosed with VP. STUDY DESIGN: We retrospectively collected and reviewed medical records from 2006 to 2018 of early multiple pregnancies that ended with a single fetus diagnosed with VP in our medical center, including three cases of twin gestation complicated by a vanishing twin and a case of multifetal reduction in triplet pregnancy. This retrospective cohort study was approved by our Institutional Clinical Research Committee. RESULTS: The database search identified 50 pregnancies that started as multiple gestations but continued as singletons. Of these, 4 pregnancies were diagnosed with VP, for a prevalence of 8.0%. For two of the four cases, the diagnosis was made during delivery as expressed by a low Apgar score at 1 and 5 min, a low cord blood pH value, newborn resuscitation, blood product transfusion, and NICU supervision. There was a statistically significant difference in the prevalence of VP in pregnancies that started as multiple gestations but continued later as singletons compared to multiple pregnancies (8.0% vs. 0.2% respectively, p < 0.0001). The OR for VP in pregnancies that started as multiple gestations but continued as singletons was 41.1 (95% CI, 12.77-131.94). CONCLUSIONS: Our findings suggest there is an increased risk of VP in conceptions that started as viable multiple gestations but continued later as singletons. If our findings supported by others, it may be prudent to consider all twins at the beginning of pregnancy to be at risk for VP, irrespective of the actual number of life fetuses at later stages of gestation.

In vitro fertilization and vasa previa: A report of two cases / Fertilização in vitro e vasa previa: relato de dois casos

Abstract Vasa previa (VP) is a dangerous obstetric condition associated with perinatal mortality and morbidity. In vitro fertilization (IVF) is a risk factor for VP due to the high incidence of abnormal placentation. The diagnosis should be made prenatally, because fetal mortality can be extremely high. We report two cases to demonstrate the accuracy of transvaginal ultrasound in the prenatal diagnosis of VP. A 40-year-old primiparous Caucasian woman with IVF pregnancy was diagnosed with VP at 29 weeks of gestation and was hospitalized for observation at 31 weeks of gestation. She delivered a male newborn weighing 2,380 g, with an Apgar score of 10 at 5 minutes, by elective cesarean section at 34 weeks + 4 days of gestation, without complications. A 36-yearold primiparous Caucasian woman with IVF pregnancy was diagnosed with placenta previa, bilobed placenta increta and VP. The cord insertion was velamentous. She was hospitalized for observation at 26 weeks of gestation. She delivered a female newborn weighing 2,140 g, with an Apgar score of 9 at 5 minutes, by emergency cesarean section at 33 weeks + 4 days of gestation due to vaginal bleeding. The prenatal diagnosis of VP was associated with a favorable outcome in the two cases, supporting previous observations that IVF is a risk factor for VP and that all IVF pregnancies should be screened by transvaginal ultrasound.

Resumo Vasa previa (VP) é uma condição obstétrica perigosa associada a mortalidade e morbidade perinatais. Fertilização in vitro (FIV) é um fator de risco para VP devido à alta incidência de placentação anormal. O diagnóstico deve ser realizado no período pré-natal, pois a possibilidade de mortalidade fetal é extremamente elevada. Relatamos dois casos para demonstrar a acurácia da ultrassonografia transvaginal no diagnóstico pré-natal de VP. Mulher caucasiana, primigesta, de 40 anos, submetida a FIV, foi diagnosticada com VP na 29ª semana de gestação e hospitalizada para observação na 31ª semana de gestação. A paciente foi submetida à cesariana eletiva com 34 semanas e 4 dias, sem complicações, com recém-nascido do sexo masculino, pesando 2.380 g, e com Apgar de 10 no 5° minuto. Mulher caucasiana, primigesta, de 36 anos, subetida a FIV, foi diagnosticada com placenta prévia, placenta bilobada, acretismo placentário e VP. Cordão umbilical com inserção velamentosa. A paciente foi hospitalizada para observação na 26ª semana de gestação. Foi submetida à cesariana de emergência com33 semanas e 4 dias por sangramento vaginal. O recém nascido do sexo feminino pesou 2.140 g, com Apgar de 9 no 5°minuto. O diagnóstico de VP no período pré-natal associou-se a um desfecho favorável nos dois casos, corroborando observações anteriores de que a FIV é um fator de risco para VP e de que todas as gestações por FIV deveriam ser avaliadas por ultrassonografia transvaginal.

In Vitro Fertilization and Vasa Previa: A Report of Two Cases.

Vasa previa (VP) is a dangerous obstetric condition associated with perinatal mortality and morbidity. In vitro fertilization (IVF) is a risk factor for VP due to the high incidence of abnormal placentation. The diagnosis should be made prenatally, because fetal mortality can be extremely high. We report two cases to demonstrate the accuracy of transvaginal ultrasound in the prenatal diagnosis of VP. A 40-year-old primiparous Caucasian woman with IVF pregnancy was diagnosed with VP at 29 weeks of gestation and was hospitalized for observation at 31 weeks of gestation. She delivered a male newborn weighing 2,380 g, with an Apgar score of 10 at 5 minutes, by elective cesarean section at 34 weeks + 4 days of gestation, without complications. A 36-year-old primiparous Caucasian woman with IVF pregnancy was diagnosed with placenta previa, bilobed placenta increta and VP. The cord insertion was velamentous. She was hospitalized for observation at 26 weeks of gestation. She delivered a female newborn weighing 2,140 g, with an Apgar score of 9 at 5 minutes, by emergency cesarean section at 33 weeks + 4 days of gestation due to vaginal bleeding. The prenatal diagnosis of VP was associated with a favorable outcome in the two cases, supporting previous observations that IVF is a risk factor for VP and that all IVF pregnancies should be screened by transvaginal ultrasound.

Vasa previa (VP) é uma condição obstétrica perigosa associada a mortalidade e morbidade perinatais. Fertilização in vitro (FIV) é um fator de risco para VP devido à alta incidência de placentação anormal. O diagnóstico deve ser realizado no período pré-natal, pois a possibilidade de mortalidade fetal é extremamente elevada. Relatamos dois casos para demonstrar a acurácia da ultrassonografia transvaginal no diagnóstico pré-natal de VP. Mulher caucasiana, primigesta, de 40 anos, submetida a FIV, foi diagnosticada com VP na 29ª semana de gestação e hospitalizada para observação na 31ª semana de gestação. A paciente foi submetida à cesariana eletiva com 34 semanas e 4 dias, sem complicações, com recém-nascido do sexo masculino, pesando 2.380 g, e com Apgar de 10 no 5° minuto. Mulher caucasiana, primigesta, de 36 anos, subetida a FIV, foi diagnosticada com placenta prévia, placenta bilobada, acretismo placentário e VP. Cordão umbilical com inserção velamentosa. A paciente foi hospitalizada para observação na 26ª semana de gestação. Foi submetida à cesariana de emergência com 33 semanas e 4 dias por sangramento vaginal. O recém nascido do sexo feminino pesou 2.140 g, com Apgar de 9 no 5°minuto. O diagnóstico de VP no período pré-natal associou-se a um desfecho favorável nos dois casos, corroborando observações anteriores de que a FIV é um fator de risco para VP e de que todas as gestações por FIV deveriam ser avaliadas por ultrassonografia transvaginal.