A Positive Pregnancy Test After a Miscarriage

It Can Take Weeks for Pregnancy Hormones to Return to Zero After a Loss

positive pregnancy test
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After you receive your miscarriage diagnosis, you might be confused if you take another pregnancy test and find that it's still positive. This is a common source of confusion but does not mean that your miscarriage diagnosis was a mistake.

There are a few explanations for this scenario.

A Positive Pregnancy Test After a Miscarriage

Pregnancy tests work by detecting the pregnancy hormone hCG (human chorionic gonadotropin) in urine.

Usually hCG is not present in the body unless a woman is pregnant, so having it in your urine is pretty conclusive for pregnancy.

However, after an embryo or fetus stops growing and a miscarriage occurs, the hormone does not disappear from a woman's body right away. The level of hCG falls back down to zero over a period of days or weeks, depending on how far along the pregnancy was when the miscarriage happened.

Because today's pregnancy tests usually detect even very low levels of hCG, taking a pregnancy test in the days or immediate weeks after your miscarriage can still show a positive result. You may also continue to feel pregnancy symptoms, even when it is 100 percent certain that you have miscarried.

All in all, it takes an average of 12 to 16 days for hCG to disappear from the body, but this can vary based on how high your hCG level was at the time of your miscarriage. It can take around a week to return to zero with a chemical pregnancy (a very early pregnancy loss) or over a month with a later loss.

 

An Incomplete Miscarriage

If it has been more than a couple of weeks since your miscarriage, you should call your doctor if you are still getting a positive pregnancy test. In this situation, your doctor may want to monitor your hCG level with blood tests.

If the level does not return to zero within a reasonable time frame, there is a chance that there might still be pregnancy tissue in your uterus, even though a miscarriage did occur.

This is known as an incomplete miscarriage. Unfortunately, it does not mean that your pregnancy is continuing or is viable.

You may need a simple surgical procedure called a D&C to remove the retained products of conception, which is usually bits of the placenta. These tissues will probably be resorbed (broken down) by your body in time, but surgery can help put a stop to heavy bleeding sooner. Bleeding is a common symptom of an incomplete miscarriage.

Could You Be Pregnant Again?

If you have been sexually active and have a positive pregnancy test soon after a miscarriage, it is also possible that you might be pregnant again. Your doctor will be able to tell you for sure one way or the other.

Although many women are not aware of this, it's possible to become pregnant during your first menstrual cycle after a miscarriage. If you are not trying to become pregnant again so soon after your pregnancy loss, you should use contraception to prevent a pregnancy until you are ready. 

A Word From Verywell

Experiencing a miscarriage can be an emotional rollercoaster and the confusion over a persistently positive pregnancy test can add to this already difficult situation.

Be assured though that it can take a variable amount of time (on average two weeks) for a woman's hCG level to disappear after a miscarriage.

That being said, if you feel like something is just not right, especially if your bleeding from your miscarriage is heavy or persistent, or if you are experiencing worsening pelvic pain or a fever with your miscarriage, be sure to seek medical guidance. 

Sources:

American Association for Clinical Chemistry. (October 29th, 2015). hcg Pregnancy Lab Tests Online

Carusi DA. Retained products of conception. In: UptoDate, Steinhauer, J (Ed), UptoDate, Waltham, MA, (2016). 

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