# Antiphospholipid syndrome and pregnancy—a hematologic perspective

## TL;DR

This paper reviews the challenges of managing antiphospholipid syndrome during pregnancy, focusing on blood clot risks and the need for better treatment strategies.

## Contribution

The paper provides a hematologic perspective on APS management during pregnancy, emphasizing late complications and treatment challenges.

## Key findings

- APS increases the risk of blood clots and adverse pregnancy outcomes.
- Current management relies on blood-thinning medications and specialist monitoring.
- More research is needed to improve personalized treatment and outcomes.

## Abstract

A state-of-the-art lecture entitled “APS and pregnancy: a haematologic perspective” was presented at the International Society on Thrombosis and Haemostasis (ISTH) Congress in 2025. Antiphospholipid syndrome (APS) is a multisystem autoimmune disorder associated with thrombotic and obstetric complications, which can often be difficult to diagnose and has limited treatment options. During pregnancy, APS presents a particularly complex set of issues with a high risk of thrombosis and adverse pregnancy-related outcomes. Since the initial description of APS by Graham Hughes et al in 1983, there have been many advancements in understanding of disease mechanisms, disease-defining criteria, and patient outcomes including pregnancy outcomes. However, there is still need for improvement, especially regarding risk stratification and optimal management to enhance pregnancy-related outcomes in APS. With few novel treatments are on the horizon, it is a clear reminder of the challenges involved in conducting clinical research during pregnancy. In this review, we will focus on a hematologic perspective of APS management relating to pregnancy, including discussion on prepregnancy counseling. There will be more of a focus on late adverse pregnancy outcomes and managing thrombosis-related issues and less emphasis on earlier pregnancy-related issues, such as recurrent miscarriage since this is more aligned with obstetric perspectives. Finally, we summarize relevant new data on this topic presented during the 2025 ISTH Congress.

•Antiphospholipid syndrome is a condition with increased risk of blood clots and pregnancy problems.•Diagnosing antiphospholipid syndrome is often difficult.•Management in pregnancy is with blood-thinning medicines and close and specialist monitoring.•More research is needed to personalize treatment and improve outcomes.

Antiphospholipid syndrome is a condition with increased risk of blood clots and pregnancy problems.

Diagnosing antiphospholipid syndrome is often difficult.

Management in pregnancy is with blood-thinning medicines and close and specialist monitoring.

More research is needed to personalize treatment and improve outcomes.