Introduction

Recurrent miscarriage — commonly defined in many clinical pathways as two or more (or three or more) consecutive pregnancy losses — affects an estimated 1–2% of couples and can be deeply distressing. The emotional toll is high, and in many casesthe cause of recurrent miscarriages will not be found.

This article explains the common causes of recurrent pregnancy loss, which investigations are evidence-based (and when to begin them), available treatments where evidence supports intervention, and how to access emotional and practical support.

💡 Note: This blog is general educational information only and does not constitute personalised medical advice. Please consult with a fertility specialist to discuss your individual situation.

 

What do we mean by “recurrent miscarriage”?

Different guidelines use slightly different thresholds. Some professional bodies define recurrent miscarriage as three or more consecutive losses, while many fertility clinicians and local practice use two or more consecutive first-trimester losses as the point to start a targeted work-up, especially if there are worrying features (advanced maternal age, prior miscarriages with genetic abnormality, or known parental chromosomal issues). Clinical discretion is important — earlier investigation may be appropriate in the presence of risk factors.

 

How common is each major cause?

Understanding likely causes helps focus investigations:

• Embryonic chromosomal abnormalities (aneuploidy): the single most common cause of sporadic and recurrent early pregnancy loss. Around half of first-trimester losses are thought to be due to chromosomal abnormalities in the embryo, and this proportion rises with maternal age.
• Uterine structural problems: congenital uterine anomalies (e.g., septum), large fibroids that distort the cavity, intrauterine adhesions (Asherman’s) or significant polyps may interfere with implantation or early growth.
• Parental chromosomal rearrangements: balanced translocations in a parent increase the risk of chromosomally unbalanced embryos.
• Antiphospholipid syndrome (APS) and other thrombophilic/immune disorders: APS is an important, potentially treatable cause of recurrent pregnancy loss.
• Endocrine abnormalities: uncontrolled thyroid disease, poorly controlled diabetes, or hyperprolactinaemia can contribute.
• Other factors: sperm DNA fragmentation, advanced paternal age, infection (rarely), or a combination of subtle causes that remain unexplained despite testing.

 

What investigations are recommended — practical pathway

A focused, evidence-based approach avoids unnecessary tests while maximising diagnostic yield. I recommend a stepwise assessment after two consecutive losses or earlier if circumstances suggest a pathological cause.

 

1. Products of conception (POC) analysis (when available)

When tissue from the miscarriage is available, chromosomal analysis of the products of conception using chromosomal microarray or next-generation sequencing can identify embryonic aneuploidy (abnormal chromosomes) as the reason for loss.

 

This is highly informative when available, since identifying a random embryonic aneuploidy provides reassurance and informs counselling about recurrence risk. I routinely offer chromosomal testing for product of conception (POC) or tissue obtained from a D&C procedure after miscarriage, but not all hospitals routinely perform POC testing. So ask your treating team about submitting tissue after a miscarriage.

 

2. Parental karyotypes

A blood karyotype for both parents is indicated when there is recurrent loss, or if POC testing shows a structural chromosomal abnormality that could arise from a parental rearrangement. Detecting a balanced translocation in the partents guides genetic counselling and reproductive options.

 

3. Uterine cavity assessment

Transvaginal ultrasound is often the first step to detect obvious fibroids or large abnormalities. If there is suspicion of a uterine septum, intrauterine adhesions or a cavity abnormality, hysteroscopy (diagnostic and therapeutic) or saline sonohysterography is appropriate. Surgical correction of correctable anomalies can improve outcomes in selected cases.

 

4. Antiphospholipid antibody testing

Testing for lupus anticoagulant, anticardiolipin and β2-glycoprotein I antibodies is part of the standard recurrent miscarriage work-up, because a confirmed diagnosis of antiphospholipid syndrome changes management in pregnancy (see treatment section). Repeat testing may be required to confirm persistence according to laboratory criteria.

 

5. Endocrine and metabolic tests

Check thyroid function (TSH), glucose/HbA1c, and prolactin to identify treatable endocrine causes.

 

6. Semen analysis and targeted male investigations

Male factors are important. Routine semen analysis is part of the assessment; in selected cases (recurrent losses with normal semen parameters), tests for sperm DNA fragmentation may be considered.

 

Management — evidence-based interventions

Treatment depends on the identified cause. Below are the main evidence-based options.

 

1. If POC shows embryonic aneuploidy

If multiple POC samples demonstrate sporadic aneuploidy, it often reflects maternal age-related meiotic errors and may not indicate a correctable parental problem.

Management often involves counselling and early monitoring in future pregnancies.

For couples who prefer a more active route, IVF with embryo testing PGT-A (preimplantation genetic testing for aneuploidy) can be considered to selectively transfer only chromosomal normal embryos.

 

2. Uterine structural problems

If a uterine septum, significant polyp or adhesions are found, hysteroscopic correction often improves the likelihood of carrying a pregnancy. Decisions about surgery must balance potential benefits with risks.

 

3. Parental chromosomal rearrangements

When a parental balanced translocation is found, genetic counselling is essential.

Options include natural conception with prenatal diagnosis, or IVF with PGT-SR ( (preimplantation genetic testing for structural rearrangement) can be considered to selectively transfer only chromosomal balanced embryos.

 

4. Antiphospholipid syndrome (APS)

In women with confirmed obstetric APS, treatment with low-dose aspirin plus prophylactic low-molecular-weight heparin during pregnancy has been shown to improve live birth rates and is the standard approach in most guidelines.

Treatment is typically started once pregnancy is confirmed and continued at least until 34–36 weeks, with individualisation as needed.

 

5. Endocrine optimisation

Correcting hypothyroidism, optimising glycaemic control in diabetes, and managing hyperprolactinaemia (if present) are important, straightforward steps that can improve outcomes.

 

6. Progesterone and supportive therapies

The role of progesterone in recurrent miscarriage is evolving. Some recent studies show benefit in specific groups (for example, women with a history of recurrent bleeding), but routine, blanket progesterone for all recurrent miscarriage cases is not universally supported. I discuss the potential benefits and side effects with my patients.

 

7. Psychological and supportive care

Early pregnancy monitoring and timely access to care are also vital components of management.

 

When should you see a specialist?

Refer to a fertility specialist or recurrent miscarriage clinic when you have:

• Two or more consecutive pregnancy losses (especially if other risk factors are present), or
• One loss plus a known risk factor (abnormal parental karyotype, maternal disease), or
• Any concern about recurrent pregnancy loss in the context of advanced maternal age or other comorbidities.

 

Early specialist involvement improves access to POC testing, genetic counselling, thrombophilia evaluation and coordinated multidisciplinary care (haematology, endocrinology, gynaecology and psychological support).

 

Practical considerations and emotional support

• Collecting tissue after miscarriage: if you wish POC testing, discuss this with your treating team early so tissue can be handled appropriately.
• Costs and access: some tests such as PGT-A have cost implications and variable availability — discuss options and funding early.
• Emotional care: recurrent loss is traumatic. Counselling, support groups and early contact with your care team improve coping and decision-making.
• Further Support and resources

Additional support is available.  You may find further information and support through Pink Elephants, Red Nose Grief and Loss, or The Miscarriage Association of Australia  if you need.

These resources offer practical guidance, peer support and counselling services for individuals and families navigating pregnancy loss.

 

Real patient example

Claire (36) had two early miscarriages. POC analysis from her most recent loss showed trisomy 16 (3 copies of chromosome 16, where normally there should be 2 copies), and parental karyotypes were normal. After counselling, Claire and her partner chose expectant management with early monitoring for their next pregnancy; she conceived naturally two months later and had early antenatal support. This example shows how identifying an embryonic aneuploidy can provide reassurance and guide an appropriate, less invasive pathway.

 

FAQs

Q: When should we start testing after a miscarriage?
A: If you want POC testing, tissue should be submitted promptly after the miscarriage. Broader investigations are reasonable after two consecutive losses or earlier if there are other risk indicators.

Q: How often do we find a cause?
A: A cause is identified in a substantial proportion of couples (varies by series and tests used). However, in up to half of couples no clear cause is found; even then, many achieve a successful pregnancy with supportive care and targeted management.

Q: Will IVF guarantee a live birth after recurrent miscarriage?
A: IVF may address some causes (tubal disease, severe male factor) and can be combined with PGT-A in selected cases, but it is not a universal guarantee. Individual counselling about expected outcomes is important.

 

Final thoughts

Recurrent miscarriage is devastating, but modern care offers many ways to investigate causes and improve the chances of a successful pregnancy. The keys are early, evidence-based investigation, multidisciplinary teamwork, and compassionate support for the emotional journey. If you’ve experienced two or more consecutive losses, consider discussing referral to a fertility specialist — early assessment expands your options and often offers reassurance and a clear plan.

 

📍Dr Alice Huang – Fertility Specialist Melbourne
Book a consultation today and let’s take the first step together.

Disclaimer: This information is general in nature and does not replace medical advice. Please consult with your treating specialist for individualised guidance.