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 generally defined as two or more pregnancy losses before 20 weeks of gestation. Some definitions require three or more losses, but many specialists now recommend evaluation after two losses, particularly for women over 35.

How Common Is It?

Single miscarriages are common, occurring in about 10 to 15 percent of recognised pregnancies. Recurrent pregnancy loss is less common, affecting approximately 1 to 2 percent of couples trying to conceive.

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: about 50 to 60 percent of early miscarriages result from chromosomal issues that occur by chance.

However, when losses recur, the probability that all of them are random decreases. While unexplained recurrent loss does occur, many cases 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.

Parental Chromosomal Abnormalities

In about 3 to 5 percent 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.

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. Even mild thyroid dysfunction can be problematic. Treatment with thyroid medication often improves outcomes.

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. Treatment approaches vary but may include metformin and careful pregnancy monitoring.

Luteal Phase Defect

If the corpus luteum does not produce enough progesterone, the uterine lining may not adequately support early pregnancy. Progesterone supplementation is often used, though its effectiveness is debated.

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 significantly improves pregnancy outcomes.

Inherited Thrombophilias

Conditions like Factor V Leiden mutation and prothrombin gene mutation affect clotting and may contribute to pregnancy loss, particularly later losses. Testing can identify these conditions, though treatment recommendations vary.

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, this remains controversial, and evidence for treatment effectiveness is limited. Be cautious about clinics offering expensive immune testing and treatments without strong evidence.

Lifestyle and Environmental Factors

Certain modifiable factors can increase miscarriage risk, including smoking, heavy alcohol consumption, obesity, and excessive caffeine intake. Addressing these factors may improve outcomes.

Unexplained Recurrent Loss

In approximately 50 percent of couples with recurrent pregnancy loss, no specific cause is identified despite thorough testing. This is frustrating, but it is important to know that even with unexplained recurrent loss, the prognosis for future pregnancy is often good with supportive care.

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

These typically include thyroid function tests, blood glucose or HbA1c, tests for antiphospholipid antibodies, thrombophilia screening (may include Factor V Leiden, prothrombin mutation, and others), and hormone levels.

Uterine Evaluation

Transvaginal ultrasound, saline infusion sonography (SIS), 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 can provide valuable information. 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) can be used to select embryos with normal chromosomes for transfer, significantly reducing miscarriage risk.

For Uterine Abnormalities

Surgical correction of uterine septum, removal of fibroids or polyps, and treatment of Asherman syndrome can improve outcomes. These procedures are typically done via hysteroscopy.

For Antiphospholipid Syndrome

Treatment with low-dose aspirin (started before conception) and heparin (started once pregnancy is confirmed) dramatically improves live birth rates in women with antiphospholipid syndrome.

For Thyroid Disorders

Thyroid medication to maintain normal thyroid function before and during pregnancy reduces miscarriage risk.

For Hormonal Issues

Progesterone supplementation is commonly prescribed in early pregnancy for women with recurrent loss, though evidence for its effectiveness is mixed. Some studies suggest benefit specifically for women with a history of recurrent loss and early bleeding.

For Unexplained Recurrent Loss

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

Tender Loving Care

Research shows that women with unexplained recurrent loss who receive supportive care, including frequent early pregnancy monitoring, emotional support, and easy access to their medical team, have better outcomes than those without such support. The reassurance of seeing a healthy heartbeat and having questions answered promptly appears to reduce stress and may improve outcomes.

Progesterone Supplementation

Often prescribed empirically for women with unexplained recurrent loss.

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 treatment, most women with recurrent pregnancy loss go on to have successful pregnancies. Even women with unexplained recurrent loss have a 60 to 70 percent chance of successful pregnancy with their next attempt, particularly with supportive care.

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

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.