Recurrent Pregnancy Loss: Understanding Why and Finding a Path Forward

If you are reading this, you may have experienced something that no one should have to go through once, let alone multiple times. The loss of a pregnancy, and then another, and perhaps another after that, carries a weight that is difficult to put into words.

You may be feeling broken, like your body has betrayed you. You may be exhausted from the cycle of hope and heartbreak. You may be questioning whether you can bear to try again. And if you are surrounded by people who do not understand, who say things like "at least you can get pregnant" or "it just was not meant to be," you may feel profoundly alone in your grief.

We want you to know that recurrent pregnancy loss is a recognised medical condition with identifiable causes in many cases. This is not about being unlucky or being punished. There are tests that can be done, answers that can sometimes be found, and treatments that can help. You deserve a thorough evaluation and compassionate care.

This guide will explain what recurrent pregnancy loss means, the possible causes, the testing that should be done, and the treatment options that may help you carry a pregnancy to term. There is hope, even when it does not feel that way.

What Is Recurrent Pregnancy Loss?

Recurrent pregnancy loss, sometimes called recurrent miscarriage, is now defined by both ESHRE and ASRM as the loss of two or more pregnancies. ASRM's 2026 committee opinion counts losses before 22 weeks of pregnancy, includes very early losses confirmed only by a pregnancy test, and excludes ectopic and molar pregnancies. Older definitions required three or more losses, and some tests (such as antiphospholipid antibody testing under ASRM guidance) are still reserved for women with three or more losses.

How Common Is It?

Single miscarriages are common: a 2021 Lancet review estimated that about 15 percent of recognised pregnancies end in miscarriage. Recurrent pregnancy loss is less common, affecting approximately 1 to 2 percent of couples.

While these numbers mean you are not alone, they also mean that recurrent loss is unusual enough to warrant investigation. Something may be contributing to your losses that can be identified and addressed.

The Importance of Investigation

After a single miscarriage, doctors often advise that it was likely a random event, usually caused by chromosomal abnormalities in the embryo. This is frustrating but true: ASRM estimates that about 50 to 60 percent of first-trimester miscarriages are due to chromosome errors in the embryo, rising to about 75 percent in women over 40.

However, when losses recur, the probability that all of them are random decreases. While unexplained recurrent loss does occur, some couples have identifiable contributing factors that can be addressed with treatment.

Possible Causes of Recurrent Pregnancy Loss

When investigating recurrent pregnancy loss, doctors look at several categories of potential causes. For an overview of various fertility conditions, our comprehensive guide can provide additional context.

Chromosomal and Genetic Factors

Embryo Chromosomal Abnormalities

Even in recurrent loss, chromosomal abnormalities in the embryo remain a common cause. The risk increases with maternal age. Testing the tissue from a miscarriage can determine whether chromosomal abnormalities were present, and ASRM now recommends this as a first-line test.

Parental Chromosomal Abnormalities

In a small proportion of couples with recurrent loss, one partner carries a balanced chromosomal translocation. This means their chromosomes are rearranged but they have all the necessary genetic material, so they are healthy. However, their eggs or sperm may end up with missing or extra chromosomal material, leading to embryos that cannot develop normally.

This can be identified through karyotype testing of both partners. Guidelines no longer recommend this for every couple: ASRM suggests it if testing of pregnancy tissue shows an unbalanced chromosome rearrangement or if tissue testing is not available, and ESHRE suggests deciding after an individual risk assessment.

Uterine Abnormalities

The shape and condition of the uterus matter for maintaining pregnancy.

Structural Abnormalities

Some women are born with uterine abnormalities such as a septate uterus (a wall of tissue dividing the uterus), bicornuate uterus (heart-shaped uterus), or unicornuate uterus (half-sized uterus). These abnormalities can affect implantation and the growing pregnancy's ability to develop normally.

Fibroids and Polyps

Fibroids, particularly those that distort the uterine cavity, and endometrial polyps can interfere with implantation and pregnancy development.

Asherman Syndrome

Scar tissue within the uterus, often from previous procedures like D&C, can affect the uterine lining and pregnancy viability.

These structural issues can often be identified through ultrasound, hysteroscopy, or MRI, and many can be surgically corrected.

Hormonal Factors

Thyroid Dysfunction

Both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) are associated with increased miscarriage risk. ASRM recommends checking TSH in everyone with recurrent loss and treating overt or subclinical hypothyroidism with levothyroxine. However, large trials have shown that levothyroxine does not help women whose thyroid function is normal but who have thyroid antibodies, so it is not recommended for them.

Uncontrolled Diabetes

Poorly controlled diabetes increases miscarriage risk. Optimising blood sugar control before and during pregnancy reduces this risk.

Polycystic Ovary Syndrome

Women with PCOS have higher rates of miscarriage, possibly related to insulin resistance, hormonal imbalances, or other factors. Metformin is sometimes used, but evidence that it prevents pregnancy loss is limited or conflicting. Careful pregnancy monitoring is sensible.

Luteal Phase Defect

It has long been suggested that if the corpus luteum does not produce enough progesterone, the uterine lining may not adequately support early pregnancy. However, there is no reliable test for this, and ESHRE does not recommend testing for luteal phase insufficiency in women with recurrent loss.

Blood Clotting Disorders (Thrombophilias)

Certain conditions that affect blood clotting can increase miscarriage risk by affecting blood flow to the placenta.

Antiphospholipid Syndrome

This autoimmune condition causes the blood to clot more easily and is one of the most important treatable causes of recurrent loss. It is identified through blood tests for antiphospholipid antibodies. Treatment with low-dose aspirin and heparin is recommended.

Inherited Thrombophilias

Conditions like Factor V Leiden mutation and prothrombin gene mutation affect clotting. However, both ESHRE and ASRM advise against routinely testing for these inherited thrombophilias in recurrent pregnancy loss, and ESHRE advises against blood-thinning treatment for them unless needed to prevent blood clots or as part of research.

Immune Factors

The relationship between the immune system and pregnancy is complex, and research in this area is ongoing.

Natural Killer Cells

Some clinics test for elevated natural killer cells and offer immune-modulating treatments. However, ESHRE and ASRM do not recommend natural killer cell testing, and ASRM considers treatments such as IVIG and intralipids ineffective. Be cautious about clinics offering expensive immune testing and treatments without strong evidence.

Lifestyle and Environmental Factors

Certain modifiable factors are associated with higher miscarriage risk, including smoking (and secondhand smoke), alcohol (more than about 3 drinks a week), obesity, and caffeine above about 100 mg a day. Addressing these factors may improve outcomes. Lifestyle factors in the male partner, such as smoking, alcohol and weight, are also worth reviewing.

Unexplained Recurrent Loss

In many couples with recurrent pregnancy loss, no specific cause is identified despite thorough testing, although testing the pregnancy tissue now explains more losses than in the past. This is frustrating, but it is important to know that even with unexplained recurrent loss, the prognosis for future pregnancy is often good.

Testing and Evaluation

If you have experienced recurrent pregnancy loss, a thorough evaluation is warranted.

For Both Partners

Karyotype Testing

A blood test that examines the chromosomes of both partners to identify balanced translocations or other abnormalities.

For Women

Blood Tests

Recommended tests typically include thyroid function (TSH) and tests for antiphospholipid antibodies (ASRM suggests these after three or more consecutive losses or a history of blood clots). An HbA1c test for diabetes is suggested if you have risk factors. Routine testing for inherited thrombophilias, thyroid antibodies, natural killer cells, prolactin (unless you have symptoms) or ovarian reserve is not recommended.

Uterine Evaluation

Imaging of the uterine cavity is recommended for everyone with recurrent loss. Transvaginal ultrasound (ideally 3D), saline infusion sonography (SIS), HSG, hysteroscopy, or MRI can assess uterine structure and identify fibroids, polyps, or abnormalities.

Testing Pregnancy Tissue

If possible, testing the chromosomes of pregnancy tissue from a miscarriage (ideally with an array-based test) can provide valuable information, and ASRM's 2026 guidance recommends it for everyone with recurrent loss. Knowing whether the loss was due to chromosomal abnormalities helps guide further investigation and treatment.

Treatment Options

Treatment depends on the underlying cause identified.

For Chromosomal Issues

If a parental balanced translocation is identified, IVF with preimplantation genetic testing (PGT-SR) can be offered to select embryos with balanced or normal chromosomes for transfer. Evidence that this leads to more live births than continuing to try naturally is limited, so genetic counselling to discuss both options is recommended. Routine PGT-A (screening embryos for extra or missing chromosomes) has limited benefit in recurrent loss; ASRM suggests it may be considered mainly for women over 40 with previous chromosomally abnormal losses.

For Uterine Abnormalities

Removal of polyps or fibroids that distort the cavity and treatment of Asherman syndrome are recommended. For a uterine septum, guidelines differ: ASRM's 2026 guidance suggests offering hysteroscopic removal through shared decision-making, while ESHRE notes that the only randomised trial showed no benefit and says it should be evaluated in research. These procedures are typically done via hysteroscopy.

For Antiphospholipid Syndrome

For women with antiphospholipid syndrome, guidelines recommend low-dose aspirin (started before conception) and preventive-dose heparin (started once pregnancy is confirmed). ESHRE notes the evidence is strongest for women with three or more losses.

For Thyroid Disorders

Thyroid medication (levothyroxine) is recommended for overt hypothyroidism and, under ASRM guidance, subclinical hypothyroidism, keeping thyroid function normal before and during pregnancy. It is not recommended if your thyroid function is normal and you only have thyroid antibodies.

For Hormonal Issues

Progesterone supplementation is commonly prescribed in early pregnancy for women with recurrent loss, but large trials found that vaginal progesterone does not improve live birth rates in unexplained recurrent loss when there is no bleeding. For women with previous miscarriages who have bleeding in a new pregnancy, vaginal progesterone may modestly improve the chance of a live birth (ESHRE notes the clearest benefit with three or more previous losses). ASRM estimates the gain in live births at around 5 percentage points.

For Unexplained Recurrent Loss

Even without an identified cause, there are supportive measures that may help.

Tender Loving Care

Older studies suggest that women with unexplained recurrent loss who receive supportive care, including frequent early pregnancy monitoring, emotional support, and easy access to their medical team, may have better outcomes than those without such support, and guidelines recommend offering this kind of care. The reassurance of seeing a healthy heartbeat and having questions answered promptly can make a hard time more bearable.

Progesterone Supplementation

Often prescribed for women with unexplained recurrent loss, but guidelines say it does not improve live birth rates unless there is bleeding in early pregnancy (see above). Aspirin or heparin without a diagnosis of antiphospholipid syndrome is not recommended.

Lifestyle Optimisation

Ensuring healthy weight, avoiding smoking and alcohol, limiting caffeine, and managing stress may all support a healthy pregnancy.

The Emotional Journey

Recurrent pregnancy loss is not just a medical condition; it is a profound emotional experience.

Grief and Trauma

Each loss carries grief, and cumulative losses can be traumatic. You may experience anxiety, depression, post-traumatic stress symptoms, or complicated grief. These responses are normal given what you have been through.

The Fear of Trying Again

After recurrent loss, the thought of trying again can be terrifying. The innocence of pregnancy, where you assume everything will be fine, is gone. Future pregnancies may be marked by anxiety rather than joy.

Seeking Support

Professional mental health support can be invaluable. Look for therapists or counselors who specialise in pregnancy loss and infertility. Support groups, whether in person or online, connect you with others who truly understand.

Your Relationship

Recurrent loss affects both partners and can strain relationships. Partners may grieve differently and on different timelines. Open communication and patience with each other are essential. Couples counselling can help if you are struggling to support each other.

Finding the Right Care

Not all healthcare providers are experienced in managing recurrent pregnancy loss. Seeking care from a specialist, typically a reproductive endocrinologist or a maternal-fetal medicine specialist, ensures you receive thorough evaluation and evidence-based treatment.

Questions to Ask

When choosing a provider, consider asking how many patients with recurrent pregnancy loss they see, what testing they recommend, what their approach to treatment is, and how they provide support during subsequent pregnancies.

Reasons for Hope

Despite the pain of recurrent loss, there are reasons for hope.

With proper evaluation and care, most women with recurrent pregnancy loss go on to have successful pregnancies. ASRM estimates that 50 to 80 percent of people with unexplained recurrent loss will succeed in their next pregnancy without any specific treatment; the chance is higher for younger women and those with fewer losses.

Every loss is heartbreaking, but each loss does not predict the next. Your past does not have to determine your future.

Sources

• ASRM Practice Committee: Recurrent pregnancy loss: a committee opinion (2026) (checked October 2026)
• ESHRE guideline: recurrent pregnancy loss, an update in 2022 (checked October 2026)
• ESHRE guideline: recurrent pregnancy loss (2017/2018) (checked October 2026)
• Quenby et al. Miscarriage matters: the epidemiological, physical, psychological, and economic costs of early pregnancy loss. Lancet, 2021 (checked October 2026)

Medical Disclaimer

This article provides general information about recurrent pregnancy loss and should not replace professional medical advice. Recurrent pregnancy loss requires individualised evaluation and treatment. Please consult with a qualified healthcare provider who specialises in this area.