Background: Pregnancy-associated VTE is associated with a high morbidity rate, with pulmonary embolism (PE) a leading cause of maternal deaths. RCOG guidelines on prevention of VTE were updated in the guideline document “Reducing the Risk of Venous Thromboembolism during Pregnancy and the Puerperium” in 2015

Aims: Our aim, in this retrospective study, was to evaluate the utility of these guidelines in preventing recurrence of VTE in pregnancy.

Methods: We identified 290 pregnancies from our local data-base, 2015-2019, in whom a past VTE was recorded in 190.  For each record, we documented women’s characteristics and assessed whether appropriate thromboprophylaxis (TP) was used as recommended and if this prevented recurrence

Results: Appropriate weight-related thromboprophylaxis with Dalteparin had been used in all cases. Four cases had breakthrough VTEs (2.11%). Of these, one case had very poor compliance, a second had severe thrombotic tendency having antiphospholipid syndrome and Factor V Leiden heterozygosity. The third had a recurrence early in her 10th pregnancy at the time of confirmed pregnancy; therefore before TP was commenced. She later had post-partum thrombophlebitis despite recommended TP, although her compliance was poor. The final case had no extra risks to explain thromboprophylactic failure. Excluding cases 1 and 3, as these did not constitute TP failure, the frequency of recurrence was low (1%).

Conclusions: Frequency of VTE recurrence was low, in keeping with the New Zealand study, Cox et al, who reported 1.2% recurrence rate on TP with Enoxaparin. The Netherland study, van Lennep et al, using Nadroparin had 5.5% recurrence rate, but all cases were in ‘high-risk’ women, as in our 2nd case. Although we use low molecular weight heparins interchangeably there are differences in their half-lives and other characteristics which could also impact on recurrence risk. We conclude that for the vast majority of cases standard weight-adjusted TP is adequate for prevention of PA-VTE

« Back to ISTH 2021 Congress

ISTH Congress Abstracts - https://abstracts.isth.org/abstract/is-standard-dose-thromboprophylaxis-tp-as-recommended-by-the-royal-college-of-obstetricians-and-gynaecologists-rcog-adequate-in-pregnancy-for-women-with-prior-venous-thrombo-embolism-vte/