Why does testing the pregnancy tissue matter so much?
Testing the pregnancy tissue matters because it is the single most informative test after a loss. ASRM’s 2026 guidance reports that when miscarriage tissue is tested, studies find an explanation for over 90 percent of women with recurrent loss.
Without the tissue result, ASRM notes, a high percentage of women stay “unexplained,” and that uncertainty often pushes them toward tests and treatments that lack evidence.
The tissue result does three useful things:
- It can explain a specific loss, which can ease the question of whether you did something wrong.
- It tells your doctor whether to look outside the embryo for a cause.
- It can identify a chromosome rearrangement that calls for testing both partners.
This is why ASRM moved tissue testing to the front of the evaluation in 2026, to be offered after a second first-trimester loss or to anyone with a history of recurrent loss. It is the step that makes the rest of the evaluation targeted instead of broad.
How is miscarriage tissue collected and tested?
Miscarriage tissue is collected either during a procedure or at home, then sent to a laboratory for chromosome analysis. The process varies by clinic, which is why asking about it ahead of time matters so much.
Common ways tissue is collected:
- During a procedure, such as a uterine aspiration or D&C, when the clinic can send the tissue directly to the lab.
- At home, when a miscarriage happens naturally or with medication. Some clinics provide a sterile container and instructions for storing and returning the tissue.
ASRM’s 2026 guidance prefers array-based testing, such as a SNP microarray, over traditional karyotyping. Traditional karyotyping requires growing cells in a lab, which sometimes fails, and it can mistakenly analyze the mother’s cells instead of the pregnancy’s. Array testing avoids the need to grow cells, and SNP arrays can detect when a sample contains mostly maternal cells.
Ask your clinic three questions: which collection method they use, what to do if a loss happens at home or after hours, and how the testing is billed.
What can the results tell me, and what can't they?
The results can tell you whether that pregnancy had a chromosome error, but not every reason a loss happened. A tissue result answers one important question very well and leaves others open.
If the result is abnormal, such as an extra or missing chromosome, that error very likely explains the loss. These errors usually happen by chance and become more common with age. ASRM notes that women over 40 with a proven chromosomal loss are one group in whom embryo testing during IVF may be worth discussing.
If the result is normal, the embryo’s chromosomes are unlikely to explain the loss, and the evaluation focuses on the uterus, TSH, antiphospholipid antibodies, and blood sugar.
If the result shows an unbalanced rearrangement, both partners are usually offered a karyotype to check for a balanced translocation.
What the result cannot do is predict your next pregnancy with certainty. A chromosomal loss does not mean the next pregnancy will have the same problem, and a normal result does not mean something is definitely wrong with you.
Is it too late if my earlier losses weren't tested?
No. Untested earlier losses do not close the door on an evaluation. ASRM’s 2026 guidance recommends offering both partners a karyotype when no tissue testing is available, and the rest of the evaluation still applies.
Without tissue results, the evaluation typically includes:
- Karyotypes for both partners
- A uterine cavity evaluation
- TSH, with treatment if it is above 4 mIU/L or the lab’s upper limit
- Antiphospholipid antibodies after three or more losses or a blood clot
- HbA1c when diabetes risk factors are present
Many women never had tissue testing, often because it was not offered or the loss happened at home without warning. That is not a failure on your part. Tissue testing only moved to the front of ASRM’s evaluation with the 2026 update.
What you can do now is plan for the future. If you become pregnant again, knowing how tissue would be tested means the information will be there if you ever need it.
How do I raise this with my doctor before it's needed?
Raise it early, as part of planning, rather than in the middle of a loss. A good moment is a preconception visit or the first appointment of a new pregnancy, when you can talk about it calmly.
Questions that keep the conversation simple:
- “If I have another loss, can we test the tissue? ASRM’s 2026 guidance recommends it after recurrent loss.”
- “What would I do if it happens at home or on a weekend?”
- “Do you use array-based testing, and how is it billed?”
- “Can we note this plan in my chart so anyone covering for you knows?”
This conversation can be painful, because it means imagining another loss. That is understandable. You might think of it the way you pack an umbrella: not because you expect rain, but because being prepared means one less thing to manage on a hard day.
Having the plan written down also means you will not have to organize logistics in a moment when you deserve to be cared for.
From Heather
None of my four losses was tested.
None of my four losses had tissue testing. They all happened early, at around nine or ten weeks, and testing never became part of my care.
The 2026 guidance lists testing the pregnancy tissue as the first step, the one that explains the most. It is a piece of my own history I can’t fill in.
I don’t share that to make anyone feel behind. Many women reading this never had their tissue tested either, and you did nothing wrong. Care looked different, and in many places it still does.
I share it because your next pregnancy can be different. You can ask the question ahead of time, gently, and have a plan written down. In Fertility Block Mapping, this is one of the simplest and most important gaps we close: not a new test today, but a decision made in advance, so the information exists if you ever need it.
