Missed miscarriages account for roughly 1 to 5 percent of all pregnancies, making them relatively uncommon but far from rare. They fall under the broader umbrella of first-trimester miscarriage, which affects about 10 to 15 percent of known pregnancies overall. What sets a missed miscarriage apart is that the embryo stops developing but your body doesn’t immediately recognize the loss, so you may have no bleeding, no cramping, and no obvious sign that anything has changed.
What a Missed Miscarriage Actually Means
In a missed miscarriage (sometimes called a “silent” or “delayed” miscarriage), the embryo either stops growing or never forms at all, yet the pregnancy tissue stays in the uterus. Your body continues producing pregnancy hormones for a time, which is why you may still feel pregnant: nausea, breast tenderness, and fatigue can all persist even after the embryo is no longer viable.
There are two forms this can take. In one, an embryo develops but its heart stops beating at some point in the first trimester. In the other, called a blighted ovum or anembryonic pregnancy, a fertilized egg implants and a gestational sac grows, but no embryo ever forms inside it. On ultrasound, this appears as an empty sac. Both are classified as missed miscarriages because they share the same defining feature: the loss happens without symptoms.
When They’re Typically Discovered
Most missed miscarriages are found during a routine ultrasound, often at the first prenatal scan between 8 and 12 weeks. Because there’s no bleeding or cramping to prompt an earlier visit, weeks can pass between when the embryo stops developing and when the loss is detected. Some people learn at their 12-week scan that the embryo stopped growing at 7 or 8 weeks.
Diagnosis requires careful confirmation. Current guidelines call for a follow-up ultrasound at least 7 to 10 days after an initial scan raises concern, particularly if the gestational sac is small or no heartbeat is yet visible. This waiting period exists because early pregnancies can look non-viable on ultrasound simply because dates are off by a few days. In documented cases, pregnancies initially flagged as empty sacs turned out to be viable at a later scan. Doctors take this seriously and will not rush to a diagnosis when there’s any ambiguity.
Why Most Missed Miscarriages Happen
Chromosomal abnormalities in the embryo are the primary cause. Research published in the International Journal of Women’s Health found that about two-thirds of missed miscarriages involved chromosomal problems in the embryo, with the most common being trisomy 16 and Turner syndrome. Across studies more broadly, chromosomal issues account for over 50 percent of all miscarriages. These are random errors in cell division that occur at or shortly after fertilization. They are not caused by anything you did or didn’t do.
Several maternal health factors can raise the odds. Being significantly underweight or overweight is associated with higher rates of embryonic chromosomal abnormalities. Vitamin D status also appears to matter: in one study, women with severe vitamin D deficiency had chromosomal abnormality rates above 86 percent in their miscarried embryos, compared to 58 percent in women with mildly insufficient levels. Elevated thyroid-stimulating hormone, a marker of underactive thyroid function, was another identified risk factor. Age plays a role too, as chromosomal errors become more frequent with advancing maternal age.
Why Symptoms Don’t Always Disappear Right Away
The reason a missed miscarriage feels so disorienting is that pregnancy hormones, particularly hCG, don’t vanish the moment the embryo stops growing. HCG normally rises rapidly in early pregnancy, doubling roughly every two to three days, before peaking around 10 to 14 weeks. When an embryo stops developing, hCG levels may plateau or decline slowly rather than dropping sharply. That gradual decline means pregnancy symptoms can linger for days or even weeks after the loss. Some women only notice a subtle fading of nausea or breast soreness, which is easy to dismiss as normal pregnancy fluctuation.
Chances of It Happening Again
Having one miscarriage of any type, including a missed miscarriage, raises your risk of another miscarriage to about 20 percent. That number is only slightly higher than the baseline risk for any pregnancy, which means the large majority of people who experience a single missed miscarriage go on to have a healthy pregnancy next time.
After two consecutive miscarriages, the risk climbs to roughly 25 percent. After three or more in a row, it reaches 30 to 40 percent. At that point, most providers will recommend testing for underlying causes like clotting disorders, hormonal imbalances, or structural issues in the uterus. For most people, though, a single missed miscarriage is an isolated event tied to a one-time chromosomal error.
What Happens After Diagnosis
Once a missed miscarriage is confirmed, there are three main paths forward: waiting for your body to pass the tissue on its own, using medication to help the process along, or having a minor surgical procedure.
Expectant Management
This means waiting for your body to recognize the loss and begin the miscarriage process naturally. Success rates for complete passage of tissue range from 75 to 95 percent within about a month. The trade-off is unpredictability. You won’t know exactly when bleeding will start, and it can take several weeks. Some people prefer this approach because it avoids medication and procedures, while others find the waiting difficult.
Medical Management
Medication can be used to prompt the uterus to expel the pregnancy tissue. The overall success rate in studies is around 84 percent, though reported rates vary widely, from 25 to 86 percent depending on factors like gestational age and dosing. You’ll typically experience cramping and heavy bleeding, often within a few hours of taking the medication. A follow-up ultrasound confirms whether the tissue has passed completely. If it hasn’t, a second dose or a procedure may be needed.
Surgical Management
A procedure called dilation and curettage (D&C) is the most reliable option for ensuring complete removal of tissue. It’s a short outpatient procedure, usually done under sedation. Concerns about future fertility after a D&C are common, but research from the Ochsner Journal found no statistically significant increase in cervical insufficiency or adverse pregnancy outcomes in women who had previously undergone the procedure. Rare complications include infection, heavy bleeding, or uterine perforation, but these are uncommon.
All three approaches are considered safe, and the choice often comes down to personal preference, how far along the pregnancy was, and whether you want more control over timing. None of the three options has been shown to affect your ability to conceive in the future.
Factors That May Lower Your Risk
Because chromosomal errors are largely random, there’s no guaranteed way to prevent a missed miscarriage. But the modifiable risk factors identified in research offer some guidance. Maintaining a healthy weight, ensuring adequate vitamin D levels, and having thyroid function checked before or early in pregnancy are all reasonable steps. If you’ve had a previous miscarriage, your provider can check these markers as part of preconception planning. For most people, these simple measures are the most actionable things within their control.