Most miscarriages (around 80%) happen in early pregnancy - the first trimester. However, very early pregnancy losses can happen before someone knows they are pregnant, which makes the total number of miscarriages difficult to measure precisely.

This, combined with the fact that tests have become more sensitive, mean that we are not only discovering pregnancies earlier, but that because we are tracking them throughout those early weeks, we now notice more losses as well.

If you have experienced embryo, pregnancy, or infant loss and are suffering, there is help available.

Firstly, therapy can be a very helpful option to explore at this time. If you are a current Illume Fertility patient, please reach out to your Patient Navigator to learn more about counseling.

Other resources to turn to:

• AllPaths Family Building support groups (a trusted organization, open to all)
• The Mourners' Bill of Rights offers beautiful, compelling statements about grief
• Miscarriage Hurts provides resources for anyone going through loss
• Pregnancy After Loss Support shares a variety of tools, articles and more

Early pregnancy loss can happen in several ways:

Biochemical pregnancy loss: A pregnancy is detected through a positive urine or blood hCG test but ends before it can be seen on an ultrasound.

Anembryonic pregnancy: A gestational sac develops, but an embryo does not develop.

Missed miscarriage: A pregnancy has stopped developing, but the pregnancy tissue has not yet passed. Some people have few or no symptoms when this occurs.

Your healthcare provider can use ultrasound, hCG testing, and other clinical information to determine what type of pregnancy loss has occurred.

Chromosomal abnormalities in the embryo are the most common cause of first-trimester miscarriage. About 50% to 60% of first-trimester miscarriages are caused by aneuploidy, which means the embryo has an abnormal number of chromosomes.

These chromosome changes usually happen by chance during the formation of the egg or sperm or during early embryo development. The likelihood of aneuploidy increases with maternal age.

Nurse Practitioner Monica Moore explains more in "Did I Cause My Pregnancy Loss?"

Pregnancy tests and blood hCG testing can identify pregnancies very early. This means some biochemical pregnancy losses are now recognized before a pregnancy can be seen on ultrasound.

Some of these losses may previously have occurred before a person knew they were pregnant. Earlier recognition can make pregnancy loss seem more common, but it does not show that the underlying miscarriage rate has increased.

Not always. In first-trimester medical guidance, the terms early pregnancy loss and miscarriage are often used interchangeably.

“Pregnancy loss” is a broader term that can describe losses at different stages of pregnancy.

In the United States, miscarriage usually refers to a pregnancy loss before 20 weeks. A loss at or after 20 weeks is considered a stillbirth.

Recurrent pregnancy loss (RPL) is the spontaneous loss of two or more pregnancies.

Under ASRM's 2026 guidance, the losses do not need to happen consecutively. A pregnancy confirmed through a positive urine or blood hCG test can count, which means biochemical pregnancy losses are included. Confirmed ectopic and molar pregnancies are excluded from the definition.

Aneuploid miscarriages also count toward RPL. In fact, chromosome abnormalities are the most commonly identified cause of both sporadic and recurrent miscarriage.

After a second miscarriage, ASRM recommends offering genetic testing of miscarriage tissue when feasible. Those results can help determine which additional evaluations are appropriate.

Recurrent pregnancy loss can have several causes, and some cases remain unexplained.

Chromosome abnormalities in the embryo are the most commonly identified cause of both sporadic and recurrent miscarriage. ASRM now recommends a step-by-step evaluation that starts with chromosome testing of miscarriage tissue when feasible and evaluation of the uterine cavity.

Based on your history and results, further testing may evaluate factors such as antiphospholipid syndrome, thyroid disease, diabetes, parental chromosome rearrangements, or certain male factors. Not every patient needs to undergo every test.

Learn more from Illume's Dr. Joshua Hurwitz here.