Pregnancy tests are built to detect the presence of the hCG hormone (human chorionic gonadotropin) in urine or blood. Generally, hCG is only in a person's body during pregnancy, so a test showing the existence of hCG is fairly conclusive for pregnancy. Thus, you may hear people refer to hCG as 'the pregnancy hormone' (though pregnancy involves many, many different hormones!). Other than pregnancy, hCG can be secreted by ovarian tumors, but these are extremely uncommon.

After an embryo or fetus ceases development and a miscarriage occurs, hCG remains in your body. Over time, the level of hCG will gradually decrease, returning to zero over a period of days or weeks. The rate depends on two main factors:

• How far along the pregnancy was when the miscarriage happened
• Genetics. Everyone is different!

Since modern pregnancy tests detect very low levels of hCG, taking a pregnancy test in the days or weeks following your miscarriage may still show a positive result. You might also continue to experience pregnancy symptoms after a miscarriage, even when it is 100% certain that you have miscarried.

On average, it takes 12 to 16 days for hCG to disappear from the body. The actual timeframe differs from person to person, and ultimately depends on your hCG level at the time of your miscarriage. For a chemical pregnancy (a very early pregnancy loss), it generally takes 1 week for hCG levels to return to zero. For a later-term miscarriage, it can take a month or more.

One recent medical study tested 443 women who had miscarriages. The researchers found that hCG levels reduced by 35 to 50 percent 2 days after a miscarriage, and 66 to 87 percent 7 days after the pregnancy resolved. As mentioned earlier, it also depends on your genetics - everyone is different.

If it has been more than ~14 days since your miscarriage and you are still testing positive via at-home pregnancy tests, then you may want to discuss with your doctor. In most cases, your doctor will monitor your hCG levels with periodic blood tests. This is known as a quantitative hCG test.

If you continue to test positive using at-home pregnancy tests, there are a few possibilities to consider:

Have you been sexually active after a miscarriage? It's possible that you might be pregnant again. To know for sure, consult with your doctor. The tests that they're able to administer, such as quantitative hCG tests, are more accurate than at-home pregnancy tests.

Although many people are not aware of this, it is possible to become pregnant during the first menstrual cycle after a miscarriage. Thus, you should use contraception to prevent pregnancy if you are not trying to become pregnant after your pregnancy loss.

After an incomplete miscarriage, your uterus will still contain pregnancy tissue. Unfortunately, this does not mean that your pregnancy is still viable. In most cases, your body will reabsorb these tissues.

In some cases, you may need a simple surgical procedure called a dilation and curettage (commonly known as a D&C). This procedure removes the unwanted tissues, which primarily consist of small pieces of the placenta. Surgery can be beneficial to stop heavy bleeding sooner; bleeding is a common symptom in an incomplete miscarriage.

A miscarriage can be an emotional rollercoaster. The confusion that comes from continually positive pregnancy tests can add to this already difficult situation. Be assured that it takes time for one's hCG levels to return to zero after a miscarriage. On average, it takes 12-16 days, but please remember that everyone is different.

If something does not feel right, or you are experiencing heavy or persistent bleeding, worsening pelvic pain, or a fever with your miscarriage, please seek medical guidance from your OBGYN or your primary care provider. We wish you the best of luck!