Recurrent Miscarriage

Recurrent miscarriage is the loss of two or more consecutive first trimester miscarriages. These include pregnancies confirmed by pregnancy test or ultrasound, as well as molar pregnancies (a particular type of pregnancy loss caused by over-development of the placenta).

Approximately 1 to 3 in every 100 women will experience recurrent miscarriage. If you have experienced two or more miscarriages there may be an underlying cause for this, therefore, tests are usually offered at this stage. The majority of women have completely normal test results.

In many cases (about half), no specific cause or risk factors are found. However, certain factors may increase the risk, such as:

Increasing age
Previous miscarriages
Alcohol and caffeine consumption
Body mass index (BMI)
Underlying medical conditions
Anatomical anomalies (where the shape of the uterus, or womb, is different)
Genetics
Male factors (e.g. sperm health).

If you have experienced two or more consecutive miscarriages you may be referred to a dedicated Pregnancy Loss Clinic at CUMH. The clinic is run by medical and midwifery staff who are committed to supporting you through this time. This can include investigations such as blood tests, pelvic ultrasounds, etc. These are talked about more in the section below.

Pregnancy Loss Clinic at CUMH

A referral to the Pregnancy Loss Clinic at CUMH can be arranged by your GP or via the hospital. The aim of the clinic is to investigate the medical causes of recurrent pregnancy loss and to provide information and support to women and their partners.

Referral is made on the basis of two consecutive first trimester pregnancy losses (recurrent miscarriage).

The clinic also takes referrals for the following:

A second trimester (more than 13 weeks gestation) pregnancy loss
A stillbirth or neonatal death.

This clinic is run by consultants and specialist midwives and is held on Ward 2 South at CUMH (first room on left after you enter double-doors to 2 South, with teardrop sign on door). Before your appointments, you will be provided with written information to help you prepare.

At the clinic, a medical history is taken and the nature of your pregnancy loss is explored. Several investigations, such as blood tests, may be suggested. Tests may begin after two consecutive miscarriages. Some tests are only carried out after the third miscarriage, based on individual history and risk factors. The decision-making process should involve you and your healthcare provider (doctor or midwife) working together.

Plans for further pregnancy are discussed with follow up visits and referrals to other services sometimes required. However if the relevant test were performed by your GP, the EPU or 4 South ward prior to your clinic visit, your results and implications for a future pregnancy will be discussed.

Investigations and Tests

The blood tests performed at the Pregnancy Loss Clinic are as follows:

Thyroid Function Tests
Antibody screen
Full blood count
Thrombophilia screen
HbA1c (if BMI >30, family history, history of gestational diabetes, high risk ethnicity, PCOS)
Parental chromosome analysis (only after three consecutive miscarriages, unless the woman is aged under 35 years and has no living children – then it will be done on the second miscarriage).

As mentioned above, these bloods may be performed by your GP before attending the Pregnancy Loss Clinic. Here you can find a link to this list of blood tests.

Following your visit to the Pregnancy Loss Clinic other tests may be recommended depending on your history. Such tests may include an ultrasound scan, which may be done to assess any anatomical issues in the womb. A hysterosalpingogram, saline installation solography, an MRI scan or even a hysteroscopy can also be used to investigate any structural issues in the womb or fallopian tube.

Tests that are not recommended

Some internet sources may suggest performing other tests following a miscarriage. Not all tests are recommended for people experiencing recurrent miscarriage.

The below tests are not advised. This is because there is not enough evidence that they will benefit people with recurrent miscarriage. For some of these, they may only be recommended in a research setting. Your healthcare provider should guide you on suitable tests.

Routine immunological screening
- Such as blood tests for human leucocyte antigen, cytokine and natural killer cell testing.

Screening for hereditary thrombophilia (clotting condition)
- Such as blood tests for inherited blood clotting conditions, including assays for Protein C, Free Protein S, Anti-Thrombin III and Activated Protein C Resistance - unless there is a family or personal history of clotting.

Infections in asymptomatic women
- Screening for infections where there are no symptoms.

Routine genetic testing of parents
- For chromosomal rearrangements. Note: this testing may be advised after an individual assessment, or if there is no pregnancy tissue available for genetic testing.

Sperm DNA fragmentation testing
- Testing irregular sperm genetics.

Treatment options

Treatment options will depend on your specific diagnosis. For conditions like antiphospholipid syndrome and thyroid disease, your healthcare provider will prescribe medications tailored to your needs. If you and your partner have chromosomal rearrangements, you may explore options such as natural conception, IVF with preimplantation genetic testing, or egg and/or sperm donation. Surgeries for a uterine anomaly (differently-shaped or septate uterus) should only be done after assessment by teams experienced in these surgeries.

In unexplained cases, medications like high-dose folic acid, aspirin, progesterone, or blood thinners may be considered in some situations. With supportive care in a specialised Early Pregnancy Unit (EPU), evidence shows that future pregnancies may be successful without medication.

It is important to understand that just because a cause or risk factor is found, it doesn't always mean there's a treatment to lower the chances of experiencing more pregnancy losses.

Treatments that are not recommended

You might have heard about other treatments that you will not be offered. The reason for this is that there may be limited evidence that the proposed treatments can reduce the risk of future pregnancy loss. In some cases, these treatments might even be harmful.

Certain treatments are not recommended. For example:

If you have an inherited blood clotting condition (thrombophilia), you should only take blood thinners such as low molecular weight heparin if you've had blood clots before, or if your specialist doctor specifically recommends them.
Fertility treatments, such as antioxidants or vitamins for sperm health, or surgical fertility treatments, have not been shown to reduce miscarriage.

In unexplained recurrent miscarriage (where no cause has been found following tests), the following treatments are not currently recommended:

Immunotherapies (treatments for the immune system)
Metformin (medication that can affect blood sugar)
Antibiotics
Endometrial scratching (treatments to the lining of the uterus)
Pre-implantation genetic testing (IVF with testing of the embryo before insertion in the uterus).

Care in any subsequent pregnancy

Pregnancy after a miscarriage can be a challenging experience. You will usually be booked into, or offered, a consultant-led antenatal clinic at CUMH for ongoing visits and checks. You should receive appropriate supportive care, timely pregnancy plans, and regular ultrasound examinations.

Risk of having another miscarriage

Unfortunately there is a lack of evidence-based treatments for recurrent miscarriage. However, the likelihood of having another miscarriage is significantly reduced with supportive care in the setting of a dedicated Early Pregnancy Unit.

No. of previous miscarriages: Likelihood of having another miscarriage:

2 or 3 28 in 100 people

4 40 in 100 people

5 47 in 100 people

≥6 64 in 100 people.

More information or support

In addition to services available within CUMH, which you can discuss with your healthcare professionals, the following may be helpful sources of information and support:

Clinical guidelines

NWIHP/RCPI Guideline: ‘Recurrent Miscarriage’
- NWIHP/RCPI Plain Language Summary: ‘Recurrent Miscarriage’
RCOG Guideline: ‘Recurrent Miscarriage’
- RCOG Patient Information Leaflet: ‘Recurrent Miscarriage’
ESHRE Guidelines: 'Recurrent Pregnancy Loss'

Information leaflets

Miscarriage Association (UK) Leaflet: ‘Recurrent Miscarriage’
Miscarriage Association (UK) Leaflet: 'Miscarriage and the Workplace'
Miscarriage Association (UK) Leaflet: ‘Pregnancy Loss and Infertility’.

Multi-lingual information videos

Websites

Pregnancy and Infant Loss Ireland: A directory of support services and knowledge for both people who experience pregnancy loss and healthcare professionals.
Miscarriage Association of Ireland: Support, help and information for women and men who experience miscarriage.