In the United States, a pregnancy loss becomes a stillbirth at 20 weeks of gestation. Before that point, it is classified as a miscarriage. This 20-week line determines how the loss is documented, what medical procedures follow, and what legal records are created.
The 20-Week Threshold
The CDC defines a stillbirth as the loss of a pregnancy at 20 weeks or later but before birth. A miscarriage covers losses before 20 weeks. The American College of Obstetricians and Gynecologists (ACOG) follows the same dividing line and adds a weight criterion: if gestational age is unknown, a fetal weight of 350 grams (about 12 ounces) or more also qualifies the loss as a stillbirth.
This distinction matters beyond terminology. Stillbirths are reported to state vital statistics offices. A fetal death certificate is filed. In most states, this paperwork is required within 5 to 14 days after delivery. Miscarriages before 20 weeks generally do not require a fetal death certificate, though some states ask physicians to file a separate report.
Definitions Vary by Country
The 20-week cutoff is a U.S. standard. The World Health Organization uses a later threshold, defining stillbirth as a baby born with no signs of life at 28 weeks or more of gestation, or weighing 1,000 grams (about 2.2 pounds) or more. This means a loss at 24 weeks might be classified as a stillbirth in the U.S. but not in WHO international comparisons. If you’re reading statistics from different countries, this gap in definitions explains why rates can look very different.
State-by-State Differences in Reporting
Even within the U.S., states handle the paperwork differently. The federal recommendation is to report fetal deaths at 20 weeks or more, or at 350 grams or more if gestational age is unknown. Most states follow this guideline, but the specific language varies. Maine, for example, defines a miscarriage as a loss before 20 weeks and requires a fetal death certificate for any loss at 20 weeks or beyond. Washington does not require a fetal death certificate for losses under 20 weeks. Arkansas requires reporting of earlier losses as well, though on different forms and under different rules.
Some states now offer certificates of stillbirth that formally acknowledge the loss, separate from the standard fetal death report used for public health tracking. These certificates can matter to families who want legal recognition of their baby.
Why the Causes Often Differ
The medical reasons behind a loss tend to shift depending on when it happens. Most miscarriages in the first trimester are caused by chromosomal problems in the embryo. After 20 weeks, the picture changes.
For stillbirths before 24 weeks, the most common causes are pregnancy complications like placental abruption (where the placenta separates from the uterine wall), infections, and preterm labor. Bacterial infections, including E. coli and group B streptococcus, are more likely to cause losses in this earlier window.
After 24 weeks, problems with blood flow through the placenta become the leading cause. High blood pressure disorders, including preeclampsia, play a larger role in later stillbirths and those near full term. Umbilical cord problems, such as knots or compression that cut off oxygen, are more likely to cause losses during labor or near the due date. Genetic conditions and structural abnormalities can cause losses at any point. In many stillbirths, no cause is found even after thorough testing.
How Common Stillbirth Is
Stillbirth is more common than many people realize. Research from Harvard’s school of public health found that more than 1 in 150 births in the U.S. end in stillbirth, a rate higher than the CDC’s previously published estimate of about 1 in 175. The risk is not evenly distributed. In low-income areas, the rate rises to about 1 in 112 births. In communities with higher proportions of Black families, it reaches roughly 1 in 95 births.
What Happens After a Stillbirth Diagnosis
A stillbirth is confirmed by ultrasound showing no fetal heartbeat. If a handheld Doppler cannot detect heart tones, an abdominal ultrasound is done as soon as possible to check for cardiac activity. Once the absence of a heartbeat is confirmed, delivery needs to happen, but it is not usually an emergency. Most people are offered labor induction, which means medication is used to start contractions so the baby is delivered vaginally. This process can take anywhere from several hours to a couple of days, depending on how the body responds.
By contrast, miscarriages in the first trimester often pass on their own or are managed with medication or a brief outpatient procedure. The later a loss occurs, the more the process resembles labor and delivery.
Physical Recovery After a Stillbirth
One thing that catches many families off guard is milk production. The body can begin producing milk as early as 16 weeks of pregnancy, so anyone who experiences a stillbirth (and even some later miscarriages) may deal with breast engorgement, pain, and leaking. This can last days, weeks, or in some cases months.
Gradual expression of small amounts of milk, just enough to relieve pressure without stimulating more production, is the most commonly recommended approach. Over-the-counter anti-inflammatory pain relievers can help with engorgement discomfort. Watching for signs of mastitis, a breast infection that causes redness, warmth, and flu-like symptoms, is important during this period. Prescription medications to suppress milk production exist but carry side effects, so they’re typically discussed individually with a provider.
The physical recovery timeline varies. Hormonal shifts after a loss at 20 or more weeks are significant, and the body needs time to return to its pre-pregnancy state, much like it would after a full-term delivery.
Why the Terminology Is Changing
Doctors have historically used the term “spontaneous abortion” for any pregnancy loss before 20 weeks. That clinical language is falling out of favor. ACOG, along with the American Academy of Family Physicians and other professional organizations, now recommends “miscarriage” or “intrauterine pregnancy loss” instead. The shift happened because patients overwhelmingly prefer language that does not include the word “abortion,” which carries associations with an intentional procedure. You may still see “spontaneous abortion” in older medical records or discharge paperwork, but it means the same thing as miscarriage.