Clotting Parameters After Medical Abortion

Venous Thromboembolism Clinical Trial

— C-PLAN  

Official title:

Measuring the Changes in Clotting Parameters Before and After Medical Abortion

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04824118
• Other study ID #: AC20164
• Status: Completed
• Start date: March 26, 2021
• Est. completion date: August 12, 2021

Study information

• Verified date: April 2022
• Source: NHS Lothian
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Venous thromboembolism (VTE - blood clots that form in deep veins or in the lungs) has been identified as a leading cause of death in economically developed countries for pregnant and recently-pregnant women.

There is evidence that clotting parameters can take up to 6 weeks to return to normal for women who have had term deliveries, however there is an absence of information on time taken for clotting parameters to normalise following abortion.

As such, existing guidelines are based solely on expert opinion and recommend durations of VTE prevention from as short as 7 days, up to 6 weeks following abortion.

All women are assessed for risk of VTE, but data are needed to inform an evidence-based approach to prevention of VTE in these women.

The findings from this pilot study have the potential to inform clinical guidance and possibly a larger study subsequently.

Description:

Sample population: Women who attend the abortion service at the Chalmers Centre to receive abortion assessment and abortion care. There will be 3 groups recruited based upon gestational age of pregnancy - Group 1: Gestation less than 10 weeks (10 participants), Group 2: Gestation 10+0 -13+6 weeks (10 participants), Group 3: Gestation 14+0-20+0 weeks (10 participants).

Information Sheet: All new patients attending the clinic will be given a copy of the participant information sheet, so that they have time to read about the study. The Information sheet will also be available on the 'research' section of the clinic website - all women are routinely directed to this page before attending clinic.

Approach by research staff: Following registration, all patients are taken for an ultrasound scan by a clinical support worker to confirm gestation. Following this, patients move to a waiting area until they can be seen for their assessment. While they are waiting, the clinic coordinator will ask the patient if they are happy to be approached by the researcher to discuss the study further. If they are happy to discuss further, the researcher will then approach and discuss the study in a private room.

Consent: If patients are happy to participate in the study, the researcher will then obtain written informed consent prior to their bloods being taken by clinic staff if bloods required for routine care, if no routine bloods are required, the researcher will obtain the blood sample. Participants will be asked if they are planning to use a hormonal form of contraception following their abortion - if yes, they would be asked to wait until they have had their second blood sample taken to commence or not taken forward into the study.

First blood test: This will be obtained on the day of clinic attendance and ultrasound scan. Blood samples (less than 20 ml) will be obtained and taken to the NHS Lothian laboratory at the Royal Infirmary of Edinburgh and for ClotPro thromboelastography point of care testing.

Second blood test: An appointment will be made to see the patient in Chalmers Centre or at their home to obtain a further blood sample to compare to the initial test. This will take place 10-14 days following mifepristone administration. For the repeat sample we will conduct a COVID-19 risk assessment and only invite them for return visit/home visit if:

1. The participant has confirmed they and close contacts are well and without suspicion of COVID-19.

2. The participant agrees to a home visit.

3. The research staff undertaking the home visit should be well and have had no known contact with a COVID-19 positive individual for the past 14 days.

If they are having an intrauterine contraceptive, implant or injection, the second blood sample can be taken when they come into clinic for this, to minimise the number of visits.

Comparison group: A comparison group, Group 4 (10 participants), who are healthy volunteers, recruited from sexual and reproductive health clinics at Chalmers Centre, will be asked to provide a single blood test for ClotPro and lab tests, and urine pregnancy test hCG to act as a nonpregnant comparison. These participants must not be using hormonal contraception and must not be pregnant. This group will be approached by clinicians working in the SRH clinics and the researcher will be on hand to obtain consent and then draw blood.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 45
• Est. completion date: August 12, 2021
• Est. primary completion date: August 12, 2021
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 16 Years and older

Eligibility

Inclusion Criteria:

Group 1:

• Pregnant and seeking abortion

• Gestation of pregnancy less than 10 weeks

• Healthy, no medical conditions

Group 2:

• Pregnant and seeking abortion

• Gestation of pregnancy between 10 and 14 weeks

• Healthy, no medical conditions

Group 3:

• Pregnant and seeking abortion

• Gestation of pregnancy between 14 to 20 weeks

• Healthy, no medical conditions

Group 4:

• Non pregnant

• Healthy, no medical conditions

• Able to speak English independently

Exclusion Criteria:

All groups:

• Unable to give informed consent

• Previous or current venous thromboembolism

• Current smoker

• Personal or family history of thrombophilia or haemophilia

• Taking medicines known to affect clotting parameters (e.g. Aspirin)

Groups 1-3:

• Planning to commence hormonal contraception prior to second blood test.

Group 4:

• Using hormonal contraception at baseline visit

Related Conditions & MeSH terms

• Abortion Early
• Abortion, Complete
• Abortion, Second Trimester
• Blood Coagulation Disorders
• Clotting Disorder
• Embolism
• Hemostatic Disorders
• Termination of Pregnancy Complicated by Embolism
• Thromboembolism
• Thrombosis
• Venous Thromboembolic Disease
• Venous Thromboembolism
• Venous Thromboses
• Venous Thrombosis

Intervention

Diagnostic Test:
• Thromboelastometry
Point of Care Test for clotting parameters (ClotPro device)
• Clotting Studies
Standard laboratory tests for clotting: International normalised ratio (INR) Prothrombin time (PT) adjusted partial thromboplastin time (aPTT) fibrinogen
• Full Blood Count
For platelet count
• Quantitative hCG
Serum human chorionic gonadotrophin
• Pregnancy Test
Point of care urinary pregnancy test

Locations

Country	Name	City	State
United Kingdom	Chalmers Centre for Sexual and Reproductive Health	Edinburgh

Sponsors (2)

Lead Sponsor	Collaborator
NHS Lothian	University of Edinburgh

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Clotting Time in Seconds	As measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Primary	Clot Formation Time in Seconds	As measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Primary	Maximal Amplitude in millimeters	On clotting curve as measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Primary	Maximum Lysis of clot in percentage	As measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Primary	Clot Lysis index in percentage	As measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Primary	Lysis time in seconds	As measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Secondary	Prothrombin Time in seconds	Assessed by laboratory tests between baseline and follow up in Groups 1-3 and in comparison with group 4.	10-14 days
Secondary	Activated Partial Thromboplastin Time in seconds	Assessed by laboratory tests between baseline and follow up in Groups 1-3 and in comparison with group 4.	10-14 days
Secondary	International Normalised Ratio (INR)	Assessed by laboratory tests between baseline and follow up in Groups 1-3 and in comparison with group 4.	10-14 days
Secondary	Fibrinogen in grams per litre	Assessed by laboratory tests between baseline and follow up in Groups 1-3 and in comparison with group 4.	10-14 days
Secondary	Platelet count (x10^9 per litre)	Assessed by laboratory tests between baseline and follow up in Groups 1-3 and in comparison with group 4.	10-14 days
Secondary	Thromboelastography parameters (comparison with non-pregnant group)	Comparison of thromboelastography parameters (as measured using ClotPro device) between Groups 1-3 with Group 4.	10-14 days
Secondary	Serum hCG in units per litre	Comparison of serum hCG levels between baseline and follow up in groups 1-3	10-14 days
Secondary	Lysis time in seconds	As measured using ClotPro device between baseline and follow up for Groups 1-3.	10-14 days
Secondary	Clot Lysis index in percentage	As measured using ClotPro device comparing Groups 1-3 with Group 4	10-14 days
Secondary	Maximum Lysis of clot in percentage	As measured using ClotPro device comparing Groups 1-3 with Group 4	10-14 days
Secondary	Maximal Amplitude in millimeters	As measured using ClotPro device comparing Groups 1-3 with Group 4.	10-14 days
Secondary	Clot Formation Time in Seconds	As measured using ClotPro device comparing Groups 1-3 with Group 4	10-14 days
Secondary	Clotting Time in Seconds	As measured using ClotPro device comparing Groups 1-3 with Group 4	10-14 days