Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 Dec 5:4:49.
doi: 10.3310/nihropenres.13696.2. eCollection 2024.

Incidence and outcomes of vasa praevia in the United Kingdom

George Attilakos  1 , Anna L David  2   3 , Ruth Tunn  4 , Marian Knight  4 , Peter Brocklehurst  5
Affiliations

Incidence and outcomes of vasa praevia in the United Kingdom

George Attilakos et al. NIHR Open Res. .

Abstract

Background: 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.

Methods: 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.

Results: 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.

Conclusions: 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.

Keywords: Keywords: Vasa praevia; UK Obstetric Surveillance System; incidence; outcomes; perinatal mortality; pregnancy; surveillance; velamentous cord insertion.

Plain language summary

Vasa praevia is a pregnancy complication in which the blood vessels that connect the mother and fetus run across the opening of the womb, without protection from the placenta or umbilical cord. During birth, the vessels can tear. This can result in rapid blood loss from the baby and in some cases, death of the baby. We investigated how common vasa praevia is in the UK, and how women with the condition and their babies fared. The UK Obstetric Surveillance System (UKOSS) collects anonymous information from all maternity units in the UK about pregnant women who have certain medical conditions. UKOSS reporters provided information about all women with vasa praevia who gave birth between December 2014 and November 2015. We identified 51 women with vasa praevia, meaning vasa praevia was diagnosed less often in the UK than we had expected based on studies from other countries. Twenty-eight women were diagnosed during the antenatal period, while 23 were diagnosed during labour or after giving birth. Pregnant women in the UK are not screened for vasa praevia as standard, and some women may have had vasa praevia that was not diagnosed. A small number (5%) of maternity units in our study did offer screening for vasa praevia in their pregnant population. One of these units identified a quarter of all the women who had vasa praevia diagnosed during pregnancy. Babies born to women whose vasa praevia was diagnosed during pregnancy had good outcomes. All of these women gave birth by planned caesarean section, and they and their babies survived. Babies born to women whose vasa praevia was suspected or diagnosed during labour or after birth had worse outcomes. Around 40% were stillborn or died shortly after birth, and about half of those who survived had brain damage caused by lack of oxygen.

PubMed Disclaimer

Conflict of interest statement

Competing interests: George Attilakos has received travel expenses from Ferring UK to present at national and international meetings. Anna David: Member of Hologic UK Perinatal Advisory Board 2017–2018 and received honorarium to present about preterm birth at British Maternal Fetal Medicine Society conference in 2018. Peter Brocklehurst has received consultancy fees from Biotest AG. Ruth Tunn: No competing interests were disclosed. Marian Knight: No competing interests were disclosed.

Figures

Figure 1.
Figure 1.. Reported and confirmed cases of vasa praevia during the study period.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Sullivan EA, Javid N, Duncombe G, et al. : Vasa previa diagnosis, clinical practice, and outcomes in Australia. Obstet Gynecol. 2017;130(3):591–8. 10.1097/AOG.0000000000002198 - DOI - PubMed
    1. Suekane T, Tachibana D, Pooh RK, et al. : Type-3 vasa previa: normal umbilical cord insertion cannot exclude vasa previa in cases with abnormal placental location. Ultrasound Obstet Gynecol. 2020;55(4):556–557. 10.1002/uog.20347 - DOI - PubMed
    1. Oyelese Y, Catanzarite V, Prefumo F, et al. : Vasa previa: the impact of prenatal diagnosis on outcomes. Obstet Gynecol. 2004;103(5 Pt 1):937–42. 10.1097/01.AOG.0000123245.48645.98 - DOI - PubMed
    1. Zhang W, Geris S, Al-Emara N, et al. : Perinatal outcome of pregnancies with prenatal diagnosis of vasa previa: systematic review and meta-analysis. Ultrasound Obstet Gynecol. 2021;57(5):710–9. 10.1002/uog.22166 - DOI - PubMed
    1. Mitha A, Chen R, Razaz N, et al. : Neurological development in children born moderately or late preterm: national cohort study. BMJ. 2024;384: e075630. 10.1136/bmj-2023-075630 - DOI - PMC - PubMed

LinkOut - more resources