NCT05318547: PREFER-PP

Assessing Women's Preferences for Postpartum Thromboprophylaxis: the PREFER-PostPartum

Status unknown NA Last updated 9 August 2023

What this trial tests

NA trial testing standard-gamble technique in Pregnancy in 52 participants. Status unknown.

Timeline

13 May 2022

Primary endpoint
12 January 2024

31 December 2024

Quick facts

Lead sponsor	Fondation Hôpital Saint-Joseph
Phase	NA
Status	Status unknown
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	none
Primary purpose	other
Enrollment	52
Start date	13 May 2022
Primary completion	12 January 2024
Estimated completion	31 December 2024
Sites	1 location across France

Drugs / interventions tested

• standard-gamble technique
• time trade-off technique

Conditions studied

• Pregnancy — all drugs for Pregnancy →

Sponsor

Fondation Hôpital Saint-Joseph — full company profile →

Who can join

18 and older, female only, with Pregnancy. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

The risk of venous thromboembolism (VTE), which consists of deep vein thrombosis (DVT) and pulmonary embolism (PE), increases during pregnancy and most strikingly in the postpartum period (6 weeks after delivery). Extensive research efforts have led to the identification of many risk factors for VTE events. Examples of such factors include maternal characteristics (personal history of VTE, thrombophilia, obesity, race) and obstetrical characteristics (methods of delivery, pre-term delivery, growth retardation). These allow care providers to risk stratify women at the time of delivery into low, moderate and high-risk women, based on experts' opinion. Further, a risk score, which was recently developed and validated on English and Swedish populations, estimates the risk of postpartum VTE in individuals.

Thromboprophylaxis (TPX) focuses on the use of short-term low-molecular-weight heparin (LMWH). LMWH is believed to reduce the risk of VTE by 50-70%, but the evidence is indirect, with a lack of large-scale randomized trial in the setting of the postpartum period. Further, LMWH is both inconvenient (subcutaneous injections) and possibly associated with haemorrhagic side effects. Alternative drugs do not exist, because direct oral anticoagulants (DOAC) and aspirin are not studied in this setting and because DOAC are contra-indicated in pregnancy and breastfeeding.

Given the unclear balance of benefits and risks, current guidelines vary greatly in the proportion of women with recommended TPX. Gassmann et al. have recently demonstrated, among a cohort of parturients at the Geneva University Hospitals: a recommendation of postpartum TPX in 40.1% of women, with an estimated mean risk of postpartum VTE of 0.12%, according to the 2015 UK guidelines (RCOG), and a recommendation of postpartum TPX in 8.7% of women, with an estimated mean risk of postpartum VTE of 0.20%, according to the 2018 US guidance (ACOG).These low risks of VTE to trigger a recommendation of TPX use contrast with that of experts' opinions, which advocate for a threshold of VTE risk of 1-3% to recommend the use of TPX. Currently, all women delivering by C-section in Geneva receive TPX regardless of their VTE risk.

This dramatic discrepancy of TPX guidance between guidelines, and between guidelines and individual experts, highlights the uncertainty in this setting. Womens' preferences would be critically important here, to guide a rationale and desired use of TPX. Quite surprisingly, such preferences have never been elicited, in spite of the very large number of births every year (5 and 4 million in Europe and the US, respectively).

To inform prescription patterns of postpartum TPX, investigators propose to conduct this prospective study to elicit values and preferences of pregnant and postpartum women.

Publications & conference data

No peer-reviewed publications indexed yet for this trial.