October is Pregnancy and Infant Loss Awareness Month, a time to recognize families who have experienced miscarriage, stillbirth, or infant loss and to help bring conversations about pregnancy loss into the open.
For anyone who has experienced a loss, statistics may offer medical context, but they cannot capture the emotional impact. Grief after pregnancy or infant loss can be profound, and there is no single timeline or correct way to process it.
For those looking for information about why pregnancy loss occurs or what options may be available after repeated losses, learning more about the medical factors involved can be a helpful place to begin.
What Is a Miscarriage?
Miscarriage is the spontaneous loss of a pregnancy before viability. Pregnancy loss is more common than many people realize. According to the American Pregnancy Association, approximately 10% to 25% of clinically recognized pregnancies end in miscarriage.
Many factors can cause a pregnancy to end. These can include genetic or chromosomal abnormalities, uterine conditions, certain hormonal or metabolic disorders, and other medical factors.
Chromosomal abnormalities are particularly common in early pregnancy loss. Updated 2026 guidance from the American Society for Reproductive Medicine (ASRM) estimates that approximately 50% to 60% of first-trimester miscarriages are caused by embryonic aneuploidy, meaning the embryo has an abnormal number of chromosomes. This is consistent with earlier research on chromosome abnormalities and miscarriage and studies examining chromosomal causes of early pregnancy loss.
Most miscarriages are sporadic, meaning that experiencing 1 loss does not necessarily indicate an underlying fertility or health condition.
What Is Recurrent Pregnancy Loss?
Recurrent pregnancy loss, commonly abbreviated as RPL, has been defined differently over the years. Current ASRM guidance defines RPL as the spontaneous loss of 2 or more pregnancies, excluding confirmed ectopic and molar pregnancies.
Importantly, the 2026 definition includes pregnancies confirmed through urine or blood hCG testing. Ultrasound or tissue confirmation is no longer required for a loss to be considered when evaluating RPL.
After 2 pregnancy losses, speaking with a reproductive endocrinologist may help identify whether further evaluation is appropriate.
An RPL evaluation will depend on an individual’s history and circumstances. A physician may review previous pregnancies and losses, medical and family history, and other health factors. Testing may include chromosome analysis of miscarriage tissue when available, assessment of uterine anatomy, and targeted testing for certain endocrine, metabolic, genetic, or autoimmune conditions.
Even after a thorough evaluation, clinicians may not identify a specific cause. For many patients with unexplained RPL, however, future pregnancy is still possible. Current ASRM guidance reports that approximately 50% to 80% of patients with unexplained RPL ultimately experience a successful pregnancy.
What Can Cause Recurrent Pregnancy Loss?
One possible cause involves chromosome rearrangements. A parent with a balanced translocation typically has all of the necessary genetic material but arranged differently. This can sometimes result in embryos with an unbalanced chromosome arrangement, increasing the risk of pregnancy loss.
Antiphospholipid syndrome (APS), an autoimmune condition associated with abnormal blood clotting, is another recognized cause of recurrent pregnancy loss. If a physician diagnoses APS, they may recommend treatment during pregnancy.
The relationship between inherited blood-clotting disorders and recurrent miscarriage is more complicated than previously believed. Current ASRM guidance does not support routine inherited thrombophilia testing for everyone experiencing RPL because recent research has not established a clear benefit. Instead, testing and treatment should be based on an individual’s medical history and risk factors.
Uterine conditions, thyroid disease, diabetes, and other health concerns may also play a role in some cases.
Age, Chromosomes, and Pregnancy Loss
Age is another important factor because the likelihood of chromosomal abnormalities in eggs increases over time.
Research summarized by the American College of Obstetricians and Gynecologists has shown that the risk of early pregnancy loss increases with maternal age. This is largely connected to the increasing frequency of chromosomal abnormalities in eggs.
That does not mean pregnancy loss is inevitable after a certain birthday. Age is 1 factor among many, and an individual’s reproductive health, medical history, and circumstances all contribute to their chances of pregnancy.
What Are the Options After Recurrent Pregnancy Loss?
There is no universal treatment for recurrent pregnancy loss because treatment depends on the suspected or confirmed cause.
A reproductive endocrinologist may recommend additional testing before deciding whether medical treatment, continued attempts at pregnancy, in vitro fertilization (IVF), genetic testing, donor gametes, or another approach should be considered.
For families pursuing donor conception, Seattle Sperm Bank’s genetic services can provide additional information about genetic counseling and resources that may help intended parents make informed family-building decisions.
What About PGT-A?
Preimplantation Genetic Testing for Aneuploidy (PGT-A) is used during IVF to evaluate embryos for chromosome number before embryo transfer. Because aneuploidy is a major cause of early miscarriage, PGT-A may be discussed with some patients who have experienced pregnancy loss.
However, the evidence is more nuanced than previously believed.
Earlier research examining chromosomal abnormalities and miscarriage helped establish the significant role chromosome errors can play in pregnancy loss. Current ASRM guidance, however, states that PGT-A has not been shown to significantly reduce miscarriage or increase live birth rates for all patients with RPL.
There may be circumstances in which PGT-A is worth discussing, particularly for patients over 40 with a confirmed previous aneuploid miscarriage. Decide with a reproductive endocrinologist after considering age, reproductive history, expected embryo yield, cost, and the potential benefits and limitations of testing.
If a known inherited condition is a concern, consider Preimplantation Genetic Testing for Monogenic Disorders (PGT-M) instead. PGT-M tests embryos for a specific single-gene condition when there is a known genetic risk.
Could Donor Sperm Be Part of the Conversation?
For some families, evaluation may identify a paternal genetic factor or another circumstance in which donor sperm becomes an option worth discussing. Donor sperm may also be part of treatment for individuals and couples building families for reasons unrelated to pregnancy loss.
When you consider donor sperm, screening matters. Seattle Sperm Bank follows a comprehensive donor testing and screening process that includes medical, genetic, infectious disease, and other evaluations before accepting a donor into the program.
Genetic screening cannot eliminate every possible reproductive risk, but it can provide intended parents and their healthcare teams with important information when planning treatment.
Finding Support After Pregnancy Loss
Pregnancy loss can carry physical and emotional effects long after the pregnancy itself has ended. Current medical guidance increasingly recognizes emotional care as an essential part of miscarriage and RPL treatment.
If you have experienced 2 or more pregnancy losses, speaking with a reproductive endocrinologist can help you learn whether an evaluation is appropriate and what your next steps may look like. Genetic counselors, mental health professionals who specialize in reproductive health, and pregnancy loss support organizations may also provide valuable support.
Pregnancy and Infant Loss Awareness Month creates space to acknowledge pregnancies and babies that were deeply loved and lives that were changed by their loss. It also offers an opportunity to remind families that questions, grief, and hope for the future can exist at the same time.