Condition category
Pregnancy and Childbirth
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
Recurrent pregnancy loss (RPL) means having three or more miscarriages in a row. It is relatively common, affecting around one in 100 women. There are many possible causes of RPL, including hormonal imbalances and problems with the shape of the womb. One of the lesser explored causes are inherited blood conditions called heritable thrombophilias, in which the blood clots abnormally easily. This can lead to the flow from the placenta to the baby becoming blocked, depriving the baby of oxygen and nutrients. The usual treatment for this involves taking blood-thinning medications such as asprin or low molecular weight heparin (LWMH), which prevent the blood from clotting unnecessarily. In Taiwan the main type of heritable thrombophilia is protein S deficiency, in which the protein S (a blot clotting agent) in the blood is either too low or does not work properly. This study takes place in two parts. In the first part, medical records of women with RPL who were treated with heparin are reviewed to see if the heparin had an effect on birth outcomes. In the second part, the aim is to find out if giving heparin to women with RPL and protein S deficiency can help to improve birth outcomes.

Who can participate?
In the first part of the study, women of child-bearing age with RPL who were being treated with heparin as part of their standard care between 2011 and 2015 can take part. In the second part of the study, women of child-bearing age with RPL and a known protein S deficiency can take part.

What does the study involve?
In the first part of the study, medical records of women with RPL treated with heparin between 2011 and 2015 are reviewed. For those women who have protein S deficiency, their pregnancy records are also reviewed to see if the heparin improved the chance of successfully having a baby without complications. In the second part of the study, women with RPL and a known protein S deficiency are given LWMH at a dose of 1mg per kilogram of weight from when they agree to take part in the study once every 12 hours until the day before they have their baby. Their medical records are reviewed at the end of the study to find out how many carried their babies to term and how many suffered from complications during or after the birth.

What are the possible benefits and risks of participating?
In the first part of the study, there are no direct benefits or risks involved with participating. In the second part of the study, participants may benefit from carrying a baby to term. There is a risk of bleeding associated with taking blood thinning medication, but doses will be carefully monitored.

Where is the study run from?
Changhua Christian Hospital (Taiwan)

When is the study starting and how long is it expected to run for?
January 2011 to December 2017

Who is funding the study?
Changhua Christian Hospital (Taiwan)

Who is the main contact?
Dr Ming Chen

Trial website

Contact information



Primary contact

Dr Ming Chen


Contact details

Changhua Christian Hospital
135 Nanhsiao Street

Additional identifiers

EudraCT number number

Protocol/serial number

Changhua Christian Hospital IRB No.: 151209

Study information

Scientific title

The role of low-molecular-weight-heparin in women with recurrent pregnancy loss and protein S deficiency


Study hypothesis

The aim of this study is to investigate the therapeutic effect of low molecular weight heparin on women with recurrent pregnancy loss and documented protein S deficiency.

Ethics approval

Changhua Christian Hospital IRB, 16/02/2016, ref: 151209

Study design

Part 1:
Retrospective cohort medical record review

Part 2:
Interventional non-randomised study

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet


Recurrent miscarriage


Part 1:
Women who had recurrent pregnancy loss (RPL) who have been prescribed heparin between 2011 and 2015 as part of their standard medical care have their medical notes reviewed. Lab tests, including genetic (karyotyping), hematological (thrombophilic factors including protein S, protein C, and anti-thrombin III), immunological (lupus anticoagulant and anti-cardiolipin antibodies IgG, IgM), as well as the past history or lab and physical exam test results to exclude coexisting medical conditions such as diabetes mellitus and chronic essential hypertension are reviewed. Women found to have a protein S deficiency have their gestational records reviewed in addition to determine gestational age of delivery, the mode of delivery, the birth body weight, and obstetric complication rate.

Part 2:
All participants receive low molecular weight heparin (enoxaparin) in a dose of 1mg/Kg every 12 hours from the time of enrollment to the day (at least 24 hours) before delivery, in addition to normal antenatal examinations and treatment. Participants medical records are reviewed following delivery to establish live birth rate and obstetric complication rate.

Intervention type



Not Applicable

Drug names


Primary outcome measure

Live birth rate is measured using the outcome of pregnancy at either abortion or live-births at the time of delivery collected from medical records.

Secondary outcome measures

Obstetric complication rate is measured using specific parameters such as the birth body weight (if it is low birth weight for gestational age, or appropriate for gestational age), the gestational age when delivery (if less than 28 weeks, between 28 and 36 weeks of gestation, or term pregnancy meaning delivered later than 36 complete weeks of gestation) at delivery collected from medical records.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Part 1:
1. Women of child-bearing age
2. Recurrent pregnancy loss
3. Treated with heparin as part of standard care between 2011 and 2015

Part 2:
1. Women of child-bearing age
2. Recurrent pregnancy loss
3. Protein S deficiency (both the free antigen and function of protein S were reduced)

Participant type


Age group




Target number of participants


Total final enrolment


Participant exclusion criteria

1. Allergic to heparin or other Low Molecular Weight Heparins
2. Problem with bruising or bleeding too easily
3. History of heparin-induced thrombocytopenia
4. Stroke
5. Recently had an operation on brain
6. Renal dysfunction

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Changhua Christian Hospital
135 Nanhsiao Street

Sponsor information


Changhua Christian Hospital

Sponsor details

135 Nanhsiao Street

Sponsor type

Hospital/treatment centre



Funder type

Hospital/treatment centre

Funder name

Changhua Christian Hospital

Alternative name(s)


Funding Body Type

private sector organisation

Funding Body Subtype

Other non-profit organizations



Results and Publications

Publication and dissemination plan

Planned publication of results in a peer reviewed journal.

Intention to publish date


Participant level data

Stored in repository

Basic results (scientific)

Publication list

2016 results in (added 30/11/2020)

Publication citations

Additional files

Editorial Notes

30/11/2020: Publication reference and total final enrolment added. 03/03/2017: internal review.