Week-by-week pregnancy reference
Miscarriage Risk by Week: Pregnancy Loss Rates & Chart
See how the remaining miscarriage risk changes across pregnancy in this fixed week-by-week reference series. Use the interactive chart for daily values and the static tables for quick comparison. These figures describe a population-level reference curve, not the outcome of an individual pregnancy.
Quick answer: In this fixed reference series, the remaining miscarriage risk is 13.5% at 6 weeks, 5.2% at 8 weeks, 2.5% at 10 weeks and 1.6% at 12 weeks. The values generally decrease as gestational age advances. On this page, “rate” refers to the remaining reference probability at that gestational age, not the number of miscarriages occurring during that particular week.
| Pregnancy week | Reference miscarriage risk | Not miscarrying |
|---|---|---|
| 6 weeks | 13.5% | 86.5% |
| 8 weeks | 5.2% | 94.8% |
| 10 weeks | 2.5% | 97.5% |
| 12 weeks | 1.6% | 98.4% |
Miscarriage Rates by Week
Tap or click the chart to inspect a specific gestational day. Keyboard users can focus the chart and use the left and right arrow keys. The default view shows miscarriage risk; the second view shows its mathematical complement.
Pregnancy Loss Rates by Week
| Gestational age | Reference miscarriage risk |
|---|---|
| 3 weeks | 30.0% |
| 4 weeks | 25.0% |
| 5 weeks | 19.0% |
| 6 weeks | 13.5% |
| 7 weeks | 8.7% |
| 8 weeks | 5.2% |
| 9 weeks | 3.5% |
| 10 weeks | 2.5% |
| 11 weeks | 2.0% |
| 12 weeks | 1.6% |
| 13 weeks | 1.3% |
| 14 weeks | 1.0% |
| 15 weeks | 0.7% |
| 16 weeks | 0.5% |
| 17 weeks | 0.4% |
| 18 weeks | 0.2% |
| 19 weeks | 0.1% |
View full day-by-day miscarriage probability table
The table uses the same unchanged 118-value series as the chart. Stored zero values near the end are displayed as <0.1% rather than suggesting that miscarriage becomes impossible.
| Gestational age | Miscarriage risk | Not miscarrying |
|---|---|---|
| Open this section to load the day-by-day table. | ||
How Miscarriage Risk Changes Week by Week
In this reference series, the decline is steepest in the earlier part of pregnancy. The whole-week value is 30% at 3 weeks, 19% at 5 weeks, 13.5% at 6 weeks and 5.2% at 8 weeks. It falls to 2.5% at 10 weeks and 1.6% at 12 weeks.
These are remaining-risk reference values at the start of each completed week. They should not be interpreted as the percentage of pregnancies that miscarry during that individual week.
How This Week-by-Week Chart Is Calculated
The chart does not create a new probability from personal information. It reads one fixed sequence of 118 daily reference values beginning at 3 weeks and 0 days. Each successive value represents the next gestational day, ending at 19 weeks and 5 days.
Whole-week figures are taken directly from the value stored for day 0 of that gestational week. The “Not miscarrying” view is calculated as 100% minus the same reference risk. It is not a separate medical model.
Chances of Miscarriage at 6, 8, 10 and 12 Weeks
- 6 weeks: 13.5% reference risk
- 8 weeks: 5.2% reference risk
- 10 weeks: 2.5% reference risk
- 12 weeks: 1.6% reference risk
These figures come from the fixed series used on this page. They are useful for comparing points on the curve, but they are not individualized predictions.
Why Miscarriage Rates Differ Between Websites
Miscarriage percentages are not universal constants. Different studies can include different patient populations, begin observation at different stages, use different definitions of pregnancy loss, or apply different ultrasound and dating criteria.
A page that reports remaining risk after a confirmed heartbeat is answering a different question from a general gestational-age chart. Mixing those populations can make a number look more precise without making it more medically meaningful.
How Pregnancy Dating Affects the Week You Use
A week-by-week chart is only as useful as the gestational age being used. If you are unsure how far along the pregnancy is, the pregnancy due date calculator can help estimate gestational age from the pregnancy information you have.
If an early ultrasound includes an embryo measurement, the crown-rump length calculator provides separate first-trimester dating context from CRL.
Does Seeing a Heartbeat Change Miscarriage Risk?
Fetal cardiac activity is a clinically relevant ultrasound finding, but this chart does not collect ultrasound information. Its percentages therefore do not automatically change after a heartbeat is documented. If cardiac activity has already been seen on ultrasound, the miscarriage risk after heartbeat calculator addresses that more specific situation.
What About hCG Levels?
A single hCG result is not the same thing as a miscarriage probability. hCG may be interpreted alongside symptoms, ultrasound findings and changes over time when clinically appropriate. For pregnancy-timing context, the hCG gestational age calculator provides a separate reference based on quantitative hCG values.
People Also Ask About Miscarriage Risk by Week
What week is miscarriage most common?
This chart cannot identify the week in which miscarriages most commonly occur because it shows the remaining reference probability at each gestational age, not the incidence of pregnancy losses occurring during each specific week.
When does miscarriage risk start to decrease?
In this fixed series, the reference percentage decreases across the displayed range, with the largest numerical changes occurring earlier in pregnancy.
Is miscarriage less likely after 7 weeks?
In this reference series, yes. The whole-week value is 8.7% at 7 weeks and 5.2% at 8 weeks, with lower values later in the series. Personal clinical assessment can differ from this general curve.
What is the miscarriage risk at 6 weeks?
The fixed reference value at 6 weeks and 0 days is 13.5%.
What is the miscarriage risk at 8 weeks?
The fixed reference value at 8 weeks and 0 days is 5.2%.
What is the miscarriage risk at 10 weeks?
The fixed reference value at 10 weeks and 0 days is 2.5%.
What is the miscarriage risk at 12 weeks?
The fixed reference value at 12 weeks and 0 days is 1.6%.
Can this chart tell me whether I am having a miscarriage?
No. A statistical chart cannot diagnose miscarriage or confirm pregnancy viability. Symptoms, examination, ultrasound and other clinical information may be needed when pregnancy loss is suspected.
When to Seek Medical Care
Contact a healthcare professional or pregnancy-care service if you have vaginal bleeding, persistent cramping, passage of tissue, unusual fluid or discharge, or other pregnancy symptoms that concern you.
Seek urgent medical attention for heavy bleeding, severe or one-sided abdominal or pelvic pain, shoulder-tip pain, marked dizziness, fainting or loss of consciousness.
Clinical Guidance Sources
- American College of Obstetricians and Gynecologists — Early Pregnancy Loss
- NICE — Ectopic pregnancy and miscarriage: diagnosis and initial management
These sources support the clinical context on miscarriage, symptoms and early-pregnancy assessment. They should not be interpreted as publishing or independently validating this site's exact 118-value day-by-day numerical series.
Reviewed: October 2026.
This page separates its fixed statistical reference series from individualized medical assessment and does not present the chart as a diagnosis or guarantee of pregnancy outcome.