Related Experiment Video
Updated: Aug 16, 2026

Assessment of Maternal Vascular Remodeling During Pregnancy in the Mouse Uterus
Published on: December 5, 2015
Venous thromboembolism in pregnancy and the puerperium: incidence and additional risk factors from a London perinatal
E L Simpson1, R A Lawrenson, A L Nightingale
1Postgraduate Medical School, Guildford, Surrey, UK.
Objective:
To determine the incidence of venous thromboembolism in pregnancy and the puerperium and to identify risk factors for pregnancy-related venous thromboembolism.
Design:
Cohort study and case-control study.
Setting:
London, UK.
Population:
395,335 women with live births or pregnancies of 24 or more weeks of gestation between 1988 and 1997.
Methods:
Data extraction from the St Mary's Maternity Information System database. Random sample of 5% for case-control study.
Main Outcome Measures:
Incidence of venous thromboembolism; odds ratios for variables associated with venous thromboembolism.
Results:
The incidence of venous thromboembolism was 85/100,000 maternities. There were approximately twice as many postpartum as antepartum events. Blood group A, multiple pregnancy, caesarean section, cardiac disease, delivery at gestational age of < 36 weeks, a body mass index of > or = 25, or more and maternal age of 35 or over were all found to increase incidence of venous thromboembolism.
Conclusions:
Although venous thromboembolism is the leading cause of maternal deaths in the UK, it is still a rare event. Most of these events are deep vein thromboses occurring in the postpartum period. Antenatally multiple birth is an important risk factor. Postnatally women who have had a caesarean section, premature delivery or history of cardiac disease should be assessed carefully for venous thromboembolism.
Related Concept Videos
Venous Thrombosis I: Introduction
Venous Thrombosis II: Clinical Manifestations and Diagnostic Studies
Venous Thrombosis III: Interprofessional Care
Pulmonary Embolism I: Introduction
Pulmonary Embolism II: Diagnostic Studies and Interprofessional Care
Pulmonary Embolism I: Introduction

