Miscarriage Risk by Week Calculator
Enter the current gestational week to see the general, population-average miscarriage risk — an estimate, not a prediction for you.
Population averages only — please speak with your doctor. This tool shows general, population-average estimates only. It cannot tell you the risk for your individual pregnancy, and every pregnancy is different. This is not medical advice — please talk with your doctor or midwife, who can discuss your personal situation with care.
In the general population, the estimated risk of miscarriage falls quickly through the first trimester. It is highest in the earliest weeks, drops markedly once a heartbeat is seen around weeks 7 to 8, and is low — often cited around 1 to 2% — after week 12. These are averages and cannot predict any individual pregnancy.
⚠️ Double-check important results. This is an educational estimate, not professional advice — and where it uses a rate, bracket or fee, those change over time. Verify anything you'll rely on, especially in legal, financial, tax or medical matters, and read our full disclaimer. Think a result is wrong? Tell us so we can fix it.
How to Use This Calculator
Enter the current gestational week of the pregnancy. The tool shows the general, population-average estimated risk of miscarriage for that stage. The figures come from published population studies and are meant to give reassurance about the overall trend, not to predict any one pregnancy.
If you are worried, please reach out to your doctor or midwife. They can talk through your individual situation, which no calculator can assess.
How the Calculation Works
The tool maps the gestational week to a population-average risk from published data. The pattern is consistent across studies: risk is highest in the earliest weeks, falls sharply once cardiac activity is detected around weeks 7 to 8, and settles low through the rest of the first trimester.
These are averages across many pregnancies. They do not account for individual factors, and they cannot tell you what will happen in a specific pregnancy — only a healthcare provider can discuss personal risk.
- Figures are population averages from published studies
- Risk drops most once a heartbeat is confirmed (around weeks 7–8)
- After week 12 the risk is commonly cited around 1–2%
- Individual risk depends on factors this tool cannot see
A Note on Using This Gently
Miscarriage is common and never the parent's fault, and statistics can feel cold at a tender time. If these numbers cause worry rather than reassurance, it is completely reasonable to close the tool and simply speak with your provider.
The overall message from the data is hopeful: for most pregnancies, the chance of continuing rises with each passing week of the first trimester.
When to Use a Miscarriage Risk Calculator
People who are pregnant use this to see how estimated miscarriage risk generally falls as pregnancy progresses week by week. Many find the declining trend reassuring in early weeks. It shows population-level estimates for education and perspective only, and is not a personal medical assessment — your provider can speak to your specific situation.
Related Calculators
Caffeine Half-Life Calculator
See how much caffeine remains in your body over time.
Open calculator →Breastfeeding Calorie Calculator
Estimate the extra daily calories needed while breastfeeding.
Open calculator →Intermittent Fasting Calculator
Find when your fast ends and your eating window from a method.
Open calculator →Odds of Having Twins Calculator
A rough twin-probability estimate from common risk factors.
Open calculator →Frequently Asked Questions
How does miscarriage risk change by week?
In population averages, risk is highest in the earliest weeks and falls sharply once a heartbeat is seen around weeks 7 to 8, then stays low — often cited near 1 to 2% — after week 12.
When does miscarriage risk drop the most?
The biggest drop typically comes once cardiac activity is confirmed on ultrasound, around weeks 7 to 8. After that point the estimated risk is much lower for most pregnancies.
Are these numbers my personal risk?
No. They are averages across many pregnancies and cannot predict an individual outcome. Your own risk depends on factors only your doctor or midwife can assess.
Is miscarriage common?
Yes, especially very early, and it is not caused by normal activity or by the parent. Many early losses happen before a pregnancy is even confirmed. Support is available — talk to your provider.
Should I be worried by these figures?
They are meant to reassure by showing risk falling over time, not to alarm. If they cause worry, please speak with your healthcare provider, who can offer context and support.
Looking for a different calculator?
CalculatorPlus has free tools across finance, construction, math, health and more — each one showing the formula and a worked example.