What Is a Chemical Pregnancy?

It Is Not Uncommon for a Chemical Pregnancy to Go Unnoticed

man consoling his wife or girlfriend.
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Imagine you take an early pregnancy test around the time your period is due and it shows a faint positive. Naturally, you get excited and start spreading the joyful news that you're expecting. Then, a few days later you get your period and the doctor says, "It was just a chemical pregnancy."

A chemical pregnancy is a term used to describe a very early miscarriage. It usually occurs before the fifth week of gestation, or less than a week after your first missed period and positive pregnancy test.

Overview

Usually, the term "chemical pregnancy" refers only to an early pregnancy loss and not the early stages of a viable pregnancy.

In a chemical pregnancy, the gestational sac is not yet large enough to be visible on an ultrasound before the miscarriage happens. The only way to verify the pregnancy has occurred is through blood tests. This is considered biochemical evidence of a pregnancy, and hence the name chemical pregnancy. That being said, it is important to understand that a chemical pregnancy is not a false positive -- it does mean that a conception occurred. The loss simply occurred very early.

In contrast, a clinical pregnancy is often defined as a pregnancy that can be visualized on ultrasound. A miscarriage after a clinical pregnancy would show the absence of a gestational sac, which had previously been seen in the uterus.

Therefore, when the pregnancy develops to the point that ultrasound could confirm the existing pregnancy, the term becomes clinical pregnancy.

Symptoms and Signs

A chemical pregnancy (very early miscarriage) does not usually have any symptoms. In fact, instead of menstrual bleeding being heavier than normal as one might expect, it is often the same as a normal period, or even lighter than usual.

In terms of a sign of a chemical pregnancy, blood tests would reveal low hCG levels that are decreasing rather than increasing.

Causes

Chemical pregnancies aren't well understood, but most doctors believe they are caused by random chromosome problems in the sperm or egg. In other words, most very early miscarriages are caused by chromosome abnormalities in the baby and certainly are not due to anything that the mother (or father) did. Another possible cause is poor implantation of the embryo in the uterus -- again, something that the mother and father did not cause.

Overall, it is hard to know what precisely causes these early miscarriages, as it is nearly impossible to retrieve any samples for chromosomal testing.

Frequency

According to the American Pregnancy Association, approximately 50 to 75 percent of all miscarriages are chemical pregnancies. The reason for this variable percentage is that it can be hard to track. Women who are not actively trying to conceive and not closely watching their menstrual cycles may have chemical pregnancies and never know it. In other cases, chemical pregnancy could be a reason (but not the only possible reason) why a menstrual period arrives a few days late.

Physical Recovery

Chemical pregnancies happen early enough that they have little effect on women’s bodies, and in many cases, they can be mistaken for a normal period that is a few days late (or even on time).

While the bleeding from a chemical pregnancy may be accompanied by more cramps than usual, recovery should be fairly swift.

Conceiving Afterwards

With a very early miscarriage, many doctors will say that it’s OK to go ahead and try again right away. In fact, according to the American College of Obstetrics and Gynecology, there is no robust scientific data to support delaying trying to get pregnant after an early pregnancy loss. That being said, every woman's case is different, so be sure talk to your doctor about what is right for your specific situation.

The good news is that if you have had a miscarriage, the chances are high that your next pregnancy will be normal.

If you have had more than one miscarriage, you can most likely still have a normal pregnancy, but it may be a good idea to talk to a doctor about some testing to rule out potentially treatable causes of recurrent miscarriages.  If you have recurrent miscarriages, you may also be referred to a fertility specialist. 

Grieving

In many cases, chemical pregnancy might put you in a unique situation from a grieving perspective. Some women don’t feel very sad over chemical pregnancies, whereas others are completely devastated emotionally. People in your life might not recognize the validity of your loss, insisting that you are wrong to grieve because it happened too early for you to get attached to the pregnancy or that “it wasn’t a real baby.”

Regardless of what anyone says, a miscarriage is a miscarriage. You do not have to justify your grief or compare it to anyone else’s grief for it to be valid. A chemical pregnancy was still a pregnancy, and for many women, it’s still a loss of a baby and grief that will always they will carry for their entire lives.

It’s also OK to not be too sad about a very early miscarriage and to decide you just want to try again. Everyone reacts differently to the situation, and there is no single, right emotional response to chemical pregnancy.

A Word From Verywell

If you do tend to grieve chemical pregnancies deeply and you are actively trying to conceive, think about perhaps waiting to test each cycle until your period is actually late. This way, you do not necessarily have to know about very early miscarriages. Many doctors recommend against early pregnancy testing for this reason.

Sources:

American College of Obstetrics and Gynecology. (May 2015). Practice Bulleting: Early Pregnancy Loss.

American Pregnancy Association. (August 2016). Miscarriage.

Promislow JHE, Baird DD, Wilcox AJ, Weinberg CR. Bleeding following pregnancy loss prior to six weeks gestation. Hum Reprod. 2007 Mar;22(3):853-57.

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