One Miscarriage vs. Recurrent Loss: When Should Testing Start?

October is Pregnancy and Infant Loss Awareness Month.

And if you've experienced a miscarriage, awareness probably isn't what you're looking for.

You want answers.

You want to know why it happened.

You want to know whether it could happen again.

And before you try to conceive again, you may be asking one very reasonable question:

Should I be tested for something first?

The answer is more nuanced than either:

“Miscarriages just happen. Try again.”

“You need 25 additional fertility tests before you even think about trying again.”

One miscarriage and recurrent pregnancy loss are not medically evaluated in exactly the same way.

But that does not mean you need to ignore your health, your history or your questions after a first loss.

The better approach is to understand what deserves attention now, what becomes appropriate after recurrent losses, and what you can review before another pregnancy without turning your fertility journey into an endless testing project.

First: One Miscarriage Is Common. That Doesn't Make It Insignificant.

Approximately half of first-trimester miscarriages are related to chromosomal abnormalities in the embryo, and that proportion increases with maternal age.

That means a miscarriage can occur even when you did everything “right.”

It also means that after one early miscarriage, an extensive recurrent-pregnancy-loss evaluation is not automatically indicated for every woman.

But here is where I think the conversation often goes wrong.

Women hear:

“We don't need to do a recurrent-loss workup yet.”

And interpret that as:

“There is nothing worth looking at.”

Those are not the same statement.

After a miscarriage, there are several different questions we can ask:

Has my body physically recovered from this pregnancy?
Was anything learned from this particular loss?
Is there something in my history that warrants earlier investigation?
Is my general health ready for another pregnancy?
Have the basic fertility and preconception pieces actually been reviewed?
If this happens again, what would we want to test differently?

Those questions are reasonable after one miscarriage.

When Does Miscarriage Become “Recurrent Pregnancy Loss”?

This is important because the definition has changed over time, and many women are still told that they need to experience three miscarriages before anyone will investigate.

Current American Society for Reproductive Medicine guidance defines recurrent pregnancy loss, or RPL, as two or more pregnancy losses.

And importantly, the updated 2026 guidance includes pregnancies confirmed by urine or blood hCG. An ultrasound-confirmed pregnancy is no longer required for a loss to count toward the definition.

So if you've experienced two losses, even if one happened very early, it is reasonable to have a different conversation with your provider than:

“Let's just try again and see.”

ACOG likewise advises evaluation after two miscarriages.

That doesn't mean every available test should suddenly be ordered.

It means the evaluation changes.

What Should Be Reviewed After One Miscarriage?

I like to divide this into two categories:

The miscarriage itself

and

your health before the next pregnancy.

1. Make Sure the Miscarriage Is Medically Complete

Depending on how your miscarriage was managed and how far along the pregnancy was, your clinician may recommend follow-up such as:

Ultrasound
hCG monitoring
Clinical follow-up
Evaluation for retained pregnancy tissue
Follow-up for ongoing heavy bleeding, fever or significant pain

This isn't fertility optimization.

It's simply making sure you've recovered safely from the pregnancy.

2. Ask Whether Anything Was Learned From the Loss

Was pregnancy tissue tested?

Was pathology performed?

Were there ultrasound findings?

Was there a subchorionic hematoma, fetal abnormality, infection concern or another clinical event that might change what your provider recommends next?

Sometimes the answer is:

No. We don't know why this miscarriage happened.

That's frustrating, but it's still useful to know exactly what information you do—and don't—have.

3. Review Your Medical and Reproductive History

One miscarriage in a woman with no other fertility or medical concerns is different from one miscarriage in someone who also has:

Years of infertility
Previous pregnancy losses
Endometriosis
Fibroids or uterine abnormalities
Very irregular cycles
Significant pelvic pain
Thyroid disease
Diabetes or insulin resistance
Heavy menstrual bleeding
Known clotting history
Autoimmune disease
Previous pelvic surgery
Significant male-factor infertility
Failed fertility treatment
A strong family history that may matter

Your history determines whether the standard timeline makes sense for you.

This is one of the reasons I don't believe every woman should receive the exact same fertility checklist.

There Is Also a Piece I Think Gets Missed: Your Basic Health Before Another Pregnancy

This is where I spend a lot of time with my fertility coaching clients.

A reproductive-loss evaluation and a preconception health review are not the same thing.

Your OB/GYN or reproductive endocrinologist may appropriately decide that you do not need a complete recurrent-miscarriage panel after one loss.

That does not mean you shouldn't make sure your basic health has been reviewed before trying again.

I want to know:

When was your last physical?

When was your last well-woman visit?

When did someone last review your basic bloodwork?

And especially:

Did anyone actually look at those results in the context of preparing for pregnancy?

Depending on your health history, symptoms and previous results, it may be reasonable to discuss things such as:

CBC
Ferritin and iron status
Thyroid function
Vitamin D
B12 and folate
Metabolic markers such as glucose or A1c when appropriate
Medications and supplements
Nutritional intake
Previous deficiencies
Gastrointestinal or absorption issues

I am not saying every woman needs every one of these tests after a miscarriage.

And I am definitely not saying that a low vitamin D or ferritin result automatically explains why a pregnancy ended.

I'm saying something simpler:

A fertility clinic's miscarriage evaluation does not replace your general preconception health care.

ACOG and ASRM specifically recommend prepregnancy assessment of medical conditions, medications, nutrition and vitamin intake—including whether women are meeting requirements for nutrients such as iron, folate, B12 and vitamin D.

If you haven't had a preventive or well-woman visit in the past year, this is an excellent time to get one scheduled.

Your primary-care physician or OB/GYN can help determine which general health tests make sense for you.

What Changes After a Second Miscarriage?

This is where the 2026 guidance becomes particularly useful.

After recurrent pregnancy loss—currently defined as two or more losses—ASRM recommends a more structured evaluation.

But even here, the goal isn't:

“Order everything.”

It's:

“Start with the tests most likely to explain the loss, and expand when the history gives us a reason.”

1. Genetic Testing of the Miscarriage Can Become Very Valuable

One of the most significant updates in the 2026 ASRM recurrent-loss guidance is the emphasis on chromosome testing of miscarriage tissue.

ASRM now recommends offering chromosome evaluation of the miscarriage after a second loss or in women with recurrent pregnancy loss, when tissue is available.

Why does this matter?

Because approximately 50–60% of first-trimester miscarriages are caused by embryonic chromosomal abnormalities.

And age matters here.

If a miscarriage is found to be chromosomally abnormal, that gives you one type of information.

If the embryo was chromosomally normal, it can make other potential explanations more important to investigate.

Knowing the chromosome status can therefore help determine which questions should come next.

If you're experiencing a miscarriage and do not plan surgical management, the updated guidance also notes that options for at-home tissue collection for genetic testing can be discussed with your medical team.

Most women have never been told that.

2. The Uterine Cavity Deserves Evaluation

ASRM recommends evaluation of the uterine cavity in women with unexplained recurrent pregnancy loss.

Depending on the situation, that might include:

HSG
Saline sonogram
Hysteroscopy

The purpose is to look for issues such as:

Uterine septum
Submucosal fibroids
Polyps
Retained pregnancy tissue
Intrauterine adhesions
Other structural abnormalities

This is particularly important because pregnancy loss itself can occasionally leave behind tissue or contribute to uterine adhesions.

If you've had previous uterine procedures, fibroids, abnormal bleeding or other uterine history, make sure your clinician knows.

3. Antiphospholipid Syndrome Is Different From General Clotting Testing

This deserves its own section because the internet often treats all clotting disorders as though they're interchangeable.

They're not.

Antiphospholipid syndrome, or APS, is an acquired autoimmune clotting disorder with established pregnancy implications.

Testing can be appropriate when clinical criteria are met.

The standard laboratory evaluation includes:

Lupus anticoagulant
Anticardiolipin IgG and IgM
Beta-2 glycoprotein I IgG and IgM

But routine inherited-thrombophilia screening—including testing everyone with recurrent miscarriage for Factor V Leiden, prothrombin mutations, MTHFR, protein C, protein S or antithrombin—is not currently recommended as a standard RPL panel.

That doesn't mean clotting history should be ignored.

If you personally have had a blood clot, have a known thrombophilia or have another relevant medical history, tell your physician. That can completely change the medical context.

What I don't want you doing is assuming:

“I had a miscarriage, therefore I need every clotting test.”

Testing should be driven by your actual history.

4. Thyroid Deserves Context, Not Just a Checkbox

Thyroid is another area where I see a lot of confusion.

Current recurrent-loss guidance recommends TSH testing when there are thyroid symptoms or risk factors, after a chromosomally normal miscarriage, or when miscarriage tissue was not tested.

And broader prepregnancy guidance is clear that known thyroid disease should be appropriately managed before pregnancy.

This is where I encourage women to look beyond:

“Did somebody order a TSH once?”

I want to know:

Do you have known thyroid disease?
Are you taking thyroid medication?
Has your dose been reviewed recently?
Were your levels rechecked after a dose adjustment?
Does your doctor know you are actively trying to conceive?
Is your thyroid being managed with pregnancy in mind?

Again, this is not about inventing a special fertility number.

It's about properly managing a real medical condition before another pregnancy.

5. Blood Sugar May Matter When Your History Suggests It

A1c is not automatically an RPL test for everyone.

But ASRM recommends assessing it when risk factors for diabetes or metabolic dysfunction are present.

Those may include things such as:

PCOS
Higher body weight
Age over 40
Family history of diabetes
Previous gestational diabetes
Other symptoms or risk factors

This is another reason the best miscarriage evaluation is individualized.

Your history should determine the next question.

6. The Male Partner Should Not Disappear From the Conversation

Miscarriage often gets treated as though it is entirely a female issue.

It isn't.

The updated ASRM guidance recognizes the association between elevated sperm DNA fragmentation and recurrent miscarriage and says sperm DNA-fragmentation testing and reproductive-urology evaluation may be considered in recurrent unexplained miscarriage or when infertility is also present.

That does not mean every couple needs DNA-fragmentation testing after one miscarriage.

But after repeated unexplained losses, particularly when standard semen testing hasn't explained anything, the male side deserves another look.

That's an important shift.

What About Progesterone?

Progesterone is probably one of the first things women ask me about after miscarriage.

Unfortunately, the answer isn't as simple as:

“You miscarried, so you must have had low progesterone.”

A low progesterone level can occur because a pregnancy is already not developing normally—it isn't always the cause of the loss.

And current evidence does not support routine progesterone treatment for every woman with unexplained recurrent pregnancy loss.

That doesn't mean progesterone is never used.

Individual pregnancy history, bleeding, prior losses and other clinical factors can affect a physician's recommendation.

The point is:

A miscarriage by itself does not prove progesterone deficiency.

If you're concerned about progesterone, ask your OB/GYN or fertility specialist how your personal pregnancy history affects whether testing or treatment is appropriate.

What I Would NOT Automatically Order After Miscarriage

This part matters just as much as the testing list.

When you're grieving, you are vulnerable to the promise that one more test will finally explain everything.

Current evidence does not support routinely ordering every woman:

Large immune panels
NK-cell testing
Broad inherited-thrombophilia panels
Endometrial receptivity testing
Microbiome panels
Mycoplasma or Ureaplasma testing specifically as an RPL evaluation
Every hormone available
Every nutrient available

Some of these tests may have legitimate uses in other clinical circumstances.

That isn't the same as saying they should automatically become part of every miscarriage workup.

The question should always be:

Why are we testing this woman for this particular thing?

This Is the Question I Use With My Clients

Before ordering another test, ask:

If this result comes back abnormal, what would we do differently?

Then ask:

If it comes back normal, would it change our plan?

If nobody can explain what either result would change, the test may provide more information without providing more clarity.

That is the difference between strategic investigation and just collecting laboratory results.

But I Also Don't Believe “Don't Over-Test” Means “Don't Look”

There is an opposite problem that deserves attention.

Women are sometimes told not to over-test—and then nobody reviews anything.

That's not what I'm advocating either.

I want to make sure we haven't confused:

“This test is not routinely recommended for every miscarriage”

with:

“Your overall health doesn't deserve evaluation.”

Those are radically different statements.

You can avoid unnecessary specialty testing and still make sure:

Your basic medical care is current
Known conditions are well managed
Nutritional deficiencies aren't being ignored
Your thyroid history is appropriately followed
Heavy menstrual bleeding isn't contributing to iron depletion
Medications and supplements are pregnancy-appropriate
Your partner has been included in the evaluation
Your fertility history has been looked at as a whole

That middle ground is where I spend a lot of time with clients.

What If This Was Your First Miscarriage?

If this was your first miscarriage, you do not need to assume something terrible has been missed.

But you also don't have to pretend it didn't happen.

I would:

Complete appropriate medical follow-up for the miscarriage.
Ask what was learned from this pregnancy.
Review your fertility and medical history for anything that warrants earlier attention.
Get your routine/preconception health care current.
Review medications, supplements and prenatal nutrition.
Decide with your provider when it is physically appropriate to try again.
Know what you would want evaluated differently if another loss occurred.

If you've also experienced infertility, are over 35, have significant symptoms or have another medical condition affecting pregnancy, your conversation may reasonably be more detailed.

For a deeper look at the questions to bring to your medical team, read:

3 Tests Before Trying Again After Miscarriage

What If You've Had Two or More Losses?

Don't let anyone tell you that you automatically have to wait for a third miscarriage before asking for an evaluation.

Current ASRM and ACOG guidance defines recurrent pregnancy loss starting at two losses.

That is the point at which I would want a much clearer plan.

Not necessarily more of everything.

A better-organized evaluation.

That may include:

Reviewing whether genetic testing of miscarriage tissue is available or was performed
Uterine cavity evaluation
Appropriate genetic evaluation based on the miscarriage results and history
APS evaluation when indicated
Thyroid assessment when indicated
Metabolic evaluation when risk factors exist
Consideration of chronic endometritis or male DNA-fragmentation evaluation in certain recurrent unexplained cases
Review of overall maternal and paternal health

And then I'd ask:

What did we actually learn?

Because the purpose of the workup is not to produce an impressive stack of laboratory results.

It's to help determine what should happen differently next time.

What If Everything Comes Back Normal?

This is difficult, but important:

Even after an appropriate recurrent-pregnancy-loss evaluation, some couples will not receive a specific explanation.

That does not mean the losses weren't real.

And it doesn't mean you did something wrong.

There is also reason for hope.

ASRM's 2026 guidance reports that many people with unexplained recurrent pregnancy loss ultimately have a successful subsequent pregnancy, with reported success rates in the range of 50–80% without a specific intervention, depending on the population studied.

That's not a guarantee.

But it is very different from:

“This keeps happening, so I must not be able to carry a pregnancy.”

After Miscarriage, You Need More Than “Try Again”

You also don't necessarily need every test someone mentions in a Facebook group.

You need to understand:

What happened

What is known

What remains unanswered

What your history changes

What deserves medical evaluation now

and

What would actually change your plan before another pregnancy

That's the work.

And sometimes, when you're physically recovering and emotionally exhausted, it is very hard to organize all of that on your own.

Need Help Figuring Out What Questions to Ask Next?

If you've experienced miscarriage and aren't sure whether you've been appropriately evaluated—or you're staring at years of test results and don't know what actually matters—we can start sorting through it together.

My free 20-minute Hope & Clarity Call is designed to help you understand where you are, what feels unresolved and whether there is an obvious next step worth discussing with your medical team.

No pressure.

No promise that one hidden test explains everything.

Just a clearer direction.

Book Your Free Hope & Clarity Call

Quick Answers

Should I have testing after one miscarriage?

Not every person needs an extensive recurrent-pregnancy-loss evaluation after one early miscarriage. Appropriate follow-up depends on the pregnancy, your age, medical history, fertility history and any other risk factors. General preconception care and review of existing health information can still be appropriate.

How many miscarriages are considered recurrent pregnancy loss?

Current ASRM guidance defines recurrent pregnancy loss as two or more pregnancy losses. ACOG also recommends evaluation after two miscarriages.

Do biochemical pregnancies count toward recurrent pregnancy loss?

Under ASRM's updated 2026 definition, pregnancies confirmed by urine or blood hCG are sufficient; ultrasound or tissue confirmation is not required.

Should miscarriage tissue be genetically tested?

The 2026 ASRM guidance recommends offering chromosome evaluation of miscarriage tissue after a second miscarriage or in patients with recurrent pregnancy loss, when feasible.

Should I get tested for Factor V Leiden after miscarriage?

Inherited-thrombophilia testing, including Factor V Leiden, is not recommended routinely for every woman with recurrent pregnancy loss. Your own history of thrombosis, known thrombophilia or other relevant medical history can change that discussion and should be reviewed with your physician.

What bloodwork should I review before trying again?

There is no universal panel for every woman. Your health history should guide testing.

However, this is an appropriate time to make sure your routine and preconception care is current. Depending on your history, your physician may review or order testing such as CBC, iron/ferritin, thyroid testing, vitamin status or metabolic markers.

The goal is not to chase arbitrary “fertility optimal” numbers.

It's to identify genuine deficiencies, medical conditions or nutritional concerns that deserve attention before another pregnancy.

Should the male partner be evaluated after recurrent miscarriage?

Yes, the male partner's health and fertility history should remain part of the conversation. In some cases of recurrent unexplained miscarriage or concurrent infertility, current ASRM guidance says sperm DNA-fragmentation testing and reproductive-urology evaluation may be considered.

Is another miscarriage inevitable if no cause is found?

No. Even when recurrent pregnancy loss remains unexplained, many women subsequently have a successful pregnancy. Current ASRM guidance reports subsequent success in many patients even without a specific treatment.