In a miscarriage your hCG levels usually fall gradually, because your body is no longer sustaining the pregnancy. A single value tells you little: your midwife or doctor looks mainly at the trend across a few days. This article calmly explains what those values mean, and what they do not.
I know you are probably reading this at a sad or uncertain moment. Take your time. This information is meant to help you understand what is happening, not to make a diagnosis. Your midwife or GP does that together with you.
What happens to your hCG level in a miscarriage?
In a miscarriage the pregnancy hormone hCG usually falls, because the placenta no longer keeps producing it. Where hCG roughly doubles every two to three days in an ongoing pregnancy, in a miscarriage you see a falling line instead. The pace of that fall differs from woman to woman.
What matters is the trend, not one number. A doctor usually arranges two or more measurements a few days apart, and reads them alongside an ultrasound and your symptoms.
Sometimes the picture is not clear straight away. A value that does not rise as expected, but also does not clearly fall, calls for extra monitoring.
How long does it take for hCG to return to zero?
After a miscarriage hCG does not leave your body at once. On average it takes about two to six weeks for the value to return to near zero. How high your hCG was at the time of the miscarriage largely determines how long it takes.
The indication below helps you get a sense of the course. These are averages, not fixed rules: your body may take less or more time.
| What | Indication | What it depends on |
|---|---|---|
| hCG back to (near) zero | Median around 19 days | The hCG level at the miscarriage |
| Full range | About 9 to 35 days | Varies strongly per woman |
| Rule of thumb in practice | Often 4 to 6 weeks | A higher starting value means a longer fall |
Your midwife or doctor may advise monitoring hCG until the value is low enough. That way you can be sure the miscarriage is complete.
Why does a pregnancy test sometimes stay positive after a miscarriage?
A pregnancy test measures hCG, and as long as there is still hCG in your body a test can stay positive. So a urine test after a miscarriage may show a line for days to weeks, even though the pregnancy is over. That is confusing, but usually not worrying.
Understanding the difference between a urine test and a blood test helps here. Read more in our article on the pregnancy test by blood or urine.
A test that stays positive beyond the expected recovery time is worth discussing with your doctor.
Can a low hCG value still be a healthy pregnancy?
Yes, sometimes it can. A low or slowly rising hCG value does not automatically mean a miscarriage, because the values vary enormously between women and between pregnancies. One measurement is therefore rarely enough to say anything with certainty.
What reassures a doctor, or instead puts them on alert, is the course over time. If the value still rises steadily, a pregnancy can continue perfectly well. How fast hCG should rise is covered in our article on the hCG doubling time.
So try not to read too much meaning into one number. That is easier said than done, I realise.
When should you seek care straight away?
A falling hCG value can also belong to an ectopic pregnancy, which can be a medical emergency. So contact your GP, midwife or the out-of-hours service immediately if you recognise any of these symptoms.
- Heavy or persistent bleeding
- Severe, often one-sided pain low in your abdomen
- Pain in your shoulder or shoulder blade
- Dizziness, fainting or a weak feeling
Not sure whether your symptoms are serious? Call anyway. It is always better to check than to wait. According to the NHG (Dutch College of General Practitioners) guideline on miscarriage, care around a (possible) miscarriage belongs with your GP or midwife.
Want to read more broadly about what hCG values mean in early pregnancy? See our overview on the hCG level in early pregnancy. We explain the b-hCG value itself there too.
Frequently asked questions
How fast does hCG fall after a miscarriage?
That differs per woman. It often takes two to six weeks for hCG to return to near zero, with a median of around nineteen days. How high your value was largely determines how long the fall takes.
Should I have my hCG checked after a miscarriage?
Sometimes your doctor or midwife advises following hCG until the value is low enough, so you know the miscarriage is complete. Whether that is needed in your situation is something you decide together with your care provider.
Can I recognise a new pregnancy from my hCG?
Only once hCG from the previous pregnancy has fully cleared does a new measurement give a reliable answer again. Discuss with your midwife or GP when testing makes sense for you.
References
- NHG-Standaard Miskraam (third revision). Dutch College of General Practitioners, 2017. Available via nhg.org.
- Thuisarts.nl, I have had a miscarriage. Dutch College of General Practitioners, 2022.
- Dutch Society of Obstetrics and Gynaecology (NVOG), patient information on miscarriage, 2021.
Every blood test result through Lunara includes a professional assessment by a BIG-registered doctor. Always discuss a (possible) miscarriage and your hCG levels with your midwife or GP.
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