What Is Recurrent Pregnancy Loss?

According to the American Society for Reproductive Medicine (ASRM), recurrent pregnancy loss is defined as the spontaneous loss of two or more pregnancies (confirmed by urine or blood hCG testing). Losses do not need to be consecutive, and early biochemical losses can count toward the definition. Other guidelines (such as some older or regional ones) have used three consecutive losses, but evaluation is often recommended after two clinical losses.
About 1–5% of couples trying to conceive experience RPL. While a single miscarriage is relatively common (occurring in roughly 10–20% of recognized pregnancies), repeated losses warrant a thorough evaluation.

Common Causes of Recurrent Pregnancy Loss

RPL is multifactorial. Known contributors include:

• Genetic and chromosomal factors (a leading category, especially in early losses)
• Uterine or anatomical abnormalities (e.g., septate uterus, fibroids, adhesions)
• Endocrine or hormonal issues (uncontrolled thyroid disease, diabetes, polycystic ovary syndrome)
• Antiphospholipid syndrome and other thrombophilias
• Immune factors
• Infections (less commonly a sole cause of RPL)
• Lifestyle and environmental factors (advanced maternal age, smoking, obesity, certain toxins)

In many cases (often estimated around 50%), no clear cause is identified even after evaluation—this is called unexplained RPL. Importantly, a large proportion of couples with unexplained RPL still go on to have a successful pregnancy with supportive care.

Genetic Causes of Recurrent Pregnancy Loss

Genetics play a major role in pregnancy loss:

• Embryonic chromosomal abnormalities — Roughly 50–60% (or more in some studies) of first-trimester miscarriages show chromosomal issues such as aneuploidy (extra or missing chromosomes, most often trisomies), polyploidy, or structural changes. These usually arise spontaneously during egg or sperm formation or early embryonic division and are often not inherited.
• Parental chromosomal rearrangements — In about 2–5% (sometimes reported up to ~4–10%) of couples with RPL, one partner carries a balanced chromosomal rearrangement (such as a reciprocal or Robertsonian translocation or inversion). The parent is typically healthy, but the rearrangement can lead to unbalanced chromosomes in the embryo, increasing the chance of miscarriage or (less commonly) a child with congenital anomalies.
• Other genetic contributions — Emerging research points to single-gene variants, copy-number variations, and factors related to sperm DNA integrity or genes involved in implantation, coagulation, and placental development. Advanced testing (chromosomal microarray on products of conception, parental karyotyping, and in select cases more comprehensive genomic studies) can help identify these.

Maternal age is a key risk factor because the chance of embryonic aneuploidy rises with age. Paternal factors, including sperm DNA fragmentation, are also receiving increased attention in recent guidelines.

Why Consult a Genetics Doctor for Recurrent Pregnancy Loss?

A clinical geneticist or genetics specialist brings focused expertise that complements routine obstetric or fertility care. Key benefits include:

• Accurate diagnosis and explanation — Genetic testing of products of conception (when available) and parental karyotyping can determine whether a loss was due to a sporadic chromosomal error or a heritable rearrangement. This information is both explanatory and prognostic.
• Risk assessment for future pregnancies — Understanding the specific genetic findings allows personalized counseling about recurrence risks.
• Guided options — Depending on results, couples may discuss preimplantation genetic testing (PGT) with IVF, prenatal diagnostic testing in a future pregnancy, use of donor gametes, or expectant management with close monitoring. Genetic counseling helps weigh the benefits, limitations, and emotional aspects of each path.
• Holistic support — Genetics specialists address the medical, emotional, and family-history dimensions of RPL. They coordinate with reproductive endocrinologists, maternal-fetal medicine specialists, and other providers.
• Avoiding unnecessary or incomplete testing — Expert guidance helps prioritize evidence-based evaluations and interpret complex results.

Guidelines from organizations such as ASRM, ESHRE, and others recommend genetic evaluation (including consideration of parental karyotyping and testing of pregnancy tissue) as part of the RPL workup, with referral for genetic counseling when abnormalities are found.

When Should You Seek a Genetics Consultation?

Consider consulting a genetics doctor if you have:

1. Two or more pregnancy losses
2. A pregnancy loss with confirmed chromosomal abnormality on testing of the tissue
3. Family history of genetic conditions, birth defects, or recurrent losses
4. Known or suspected parental chromosomal rearrangement
5. Unexplained RPL after basic evaluations
6. Plans for IVF and interest in genetic testing options

Early evaluation can provide clarity and reduce the emotional burden of uncertainty.

Hope and Next Steps with Expert Care

Many couples with RPL ultimately achieve a healthy pregnancy. Identifying a genetic factor—or ruling one out—empowers informed decisions and targeted support. Even when no specific cause is found, understanding the statistics and available monitoring strategies can be reassuring.
Dr. Veronica Arora, Clinical Geneticist and Obstetrician-Gynecologist at Sir Ganga Ram Hospital, New Delhi, specializes in the genetic evaluation and counseling of couples facing recurrent pregnancy loss. With dual expertise in obstetrics-gynecology and medical genetics (including European certification), she offers comprehensive workups, clear explanations, and personalized guidance.