The CPLAN study: Clotting Parameters after medicaL AbortioN

Area of Science:

• Obstetrics and Gynecology
• Hematology
• Thrombosis Research

Background:

• Limited data exists on coagulation changes throughout pregnancy, puerperium, and post-abortion.
• Current guidance for post-abortion thromboprophylaxis is based on expert opinion and extrapolated from post-birth recommendations, with durations varying widely.
• Understanding these coagulation dynamics is crucial for assessing venous thromboembolism (VTE) risk.

Purpose of the Study:

• To investigate coagulation parameters in early pregnancy and following medical abortion.
• To compare coagulation markers between pregnant women undergoing medical abortion and non-pregnant controls.
• To inform VTE risk assessment and thromboprophylaxis guidelines post-abortion.

Main Methods:

• A prospective study was conducted in a UK community abortion clinic.
• Healthy pregnant women (<12 weeks gestation) and non-pregnant controls were recruited.
• Coagulation markers (Clauss-fibrinogen, PT, aPTT, platelets) and viscoelastic measures were assessed pre- and post-abortion using the ClotPro® system.

Main Results:

• Forty-five women (24 pregnant, 21 non-pregnant) were included.
• Clauss-fibrinogen was slightly elevated pre-abortion compared to controls but remained within normal limits.
• Minor pro-coagulant changes were observed in viscoelastic measures, with small absolute differences within normal ranges.

Conclusions:

• First-trimester pregnancy and medical abortion are associated with minimal changes in coagulation parameters.
• These coagulation changes largely resolve within 10-14 days post-abortion.
• Shorter thromboprophylaxis durations may be adequate post-abortion compared to post-birth for individuals at high VTE risk.