Attilakos George, David Anna L, Tunn Ruth, Knight Marian, Brocklehurst Peter
Fetal Medicine Unit, University College London Hospitals NHS Foundation Trust, 235 Euston Road, London, NW1 2BU, UK.
Elizabeth Garrett Anderson Institute for Women's Health, University College London, Medical School Building, Huntley Street, London, WC1E 6AU, UK.
NIHR Open Res. 2024 Dec 5;4:49. doi: 10.3310/nihropenres.13696.1. eCollection 2024.
Vasa praevia is an obstetric condition in which the fetal vessels run through the membrane over the internal cervical os, unprotected by the placenta or umbilical cord. It is associated with perinatal mortality if not diagnosed antenatally. We estimated the incidence and investigated outcomes of vasa praevia in the UK.
We conducted a population-based descriptive study using the UK Obstetric Surveillance System (UKOSS). Cases were identified prospectively through monthly UKOSS submissions from all UK hospitals with obstetrician-led maternity units. All women diagnosed with vasa praevia who gave birth between 1st December 2014 and 30th November 2015 were included. The main outcome was estimated incidence of vasa praevia with 95% confidence intervals, using 2015 maternities as the denominator.
Fifty-one women met the case definition. The estimated incidence of diagnosed vasa praevia was 6.64 per 100,000 maternities (95% CI 5.05-8.73). Of 198 units, 10 (5%) had a vasa praevia screening programme; one of these 10 units identified 25% of the antenatally diagnosed cases. Among women who had vasa praevia diagnosed or suspected antenatally (n=28, 55%), there were no perinatal deaths or hypoxic ischaemic encephalopathy (HIE). Twenty-four women with antenatal diagnosis were hospitalised at a median 32 weeks' gestation and caesarean section was scheduled at a median 36 weeks' gestation. When vasa praevia was diagnosed peripartum (n=23, 45%), the perinatal mortality rate was 37.5% and 47% of survivors developed HIE.
The incidence of diagnosed vasa praevia was lower than anticipated. There was high perinatal mortality and morbidity for cases not diagnosed antenatally. The incidence of antenatally identified cases was much higher in the few centres that actively screened for this condition, and the perinatal outcomes were better. However, this group were all delivered by caesarean section and may include women who would not have experienced any adverse perinatal outcome.
前置血管是一种产科情况，即胎儿血管穿过宫颈内口上方的胎膜，未受到胎盘或脐带的保护。若产前未诊断出来，会导致围产期死亡。我们估算了英国前置血管的发病率并调查了其结局。
我们使用英国产科监测系统（UKOSS）进行了一项基于人群的描述性研究。通过英国所有由产科医生主导的产科病房每月提交给UKOSS的数据前瞻性地确定病例。纳入了2014年12月1日至2015年11月30日期间所有诊断为前置血管并分娩的妇女。以2015年的分娩数为分母，主要结局是估算前置血管的发病率及95%置信区间。
51名妇女符合病例定义。诊断为前置血管的估算发病率为每10万例分娩6.64例（95%CI 5.05 - 8.73）。在198个产科病房中，10个（5%）有前置血管筛查项目；这10个病房中的1个识别出了25%的产前诊断病例。在产前诊断或怀疑为前置血管的妇女中（n = 28，55%），没有围产期死亡或缺氧缺血性脑病（HIE）。24名产前诊断的妇女在妊娠32周时中位数住院，剖宫产计划在妊娠36周时中位数进行。当在分娩期诊断出前置血管时（n = 23，45%），围产期死亡率为37.5%，47%的存活者发生了HIE。
诊断为前置血管的发病率低于预期。未产前诊断出的病例围产期死亡率和发病率较高。在少数积极筛查该情况的中心，产前确诊病例的发病率要高得多，围产期结局也更好。然而，这组病例均通过剖宫产分娩，可能包括那些原本不会经历任何不良围产期结局的妇女。
