What to Know about Chemical Pregnancy “Early Miscarriage”

Since pregnancy tests are able to detect pregnancy earlier than ever before, it’s becoming more common for women to detect a chemical pregnancy. A chemical pregnancy is an early pregnancy loss that occurs shortly after implantation. Before ultra sensitive pregnancy tests hit the market, chemical (aka biochemical) pregnancies were not possible for women to detect on their own. Today, women who are actively trying to conceive and taking early pregnancy tests or, going through fertility treatments and monitoring hCG levels, may become aware of having had a chemical pregnancy. 

Chemical pregnancies, miscarriages, implantation bleeding, and, period vs pregnancy symptoms, all can lead to total confusion when trying to conceive. In this blog post, we cover the most commonly asked questions regarding a chemical pregnancy. 

 

What is a chemical pregnancy:

A chemical pregnancy is when an embryo attaches to the uterus and releases the hormone human chorionic gonadotropin (hCG), however, fails to progress.  Shortly after the positive reading, menstrual bleeding starts and the pregnancy does not progress into a clinical pregnancy.

Chemical pregnancies are failed pregnancies that occur even before an ultrasound could confirm a pregnancy, which is typically around 5-6 weeks (source).

 

How can I tell if I had a chemical pregnancy:

When you take an early pregnancy test (before 5-6 weeks gestation) and then shortly after the positive reading, menstrual bleeding starts and a new pregnancy test now shows the hCG levels have plummeted and/or the pregnancy test is now negative, you most likely had a chemical pregnancy.

In most cases, you will have no symptoms of a chemical pregnancy and since the pregnancy was not viable past 5-6 weeks, hormones remained low and therefore, you most likely did not experience any pregnancy symptoms such as fatigue or nausea.  In fact, most women who are not taking early pregnancy tests never knew they were ever pregnant.

 

Do I need to wait a certain amount of time to try again:

The only reason not to try again right away is if you are not emotionally ready. Otherwise there are no reported contraindications to trying immediately after a chemical pregnancy. Your fertility and ovulation continues as normal. In fact, some research finds that trying again will result in a higher chance of conception (source).

 

What is the difference between a chemical pregnancy and implantation bleeding:

It can be difficult to distinguish between implantation bleeding and bleeding caused by a chemical pregnancy. Implantation bleeding happens when the fertilized egg implants into the uterus lining. On average,  implantation happens about 6- 12 days after fertilization. Many women do not have implantation bleeding, but if they do, it is typically light spotting. A chemical pregnancy will be more likely to involve heavier bleeding, cramping and perhaps passing tissue from the vagina.

Both implantation bleeding and chemical pregnancy’s vary from individual to individual, so if you experience any bleeding after a positive pregnancy test, the American Congress of Obstetricians and Gynecologists (ACOG) recommends calling your doctor.

 

For women who are still not sure if they are experiencing their monthly period or implantation bleeding, it is recommended to wait three days before taking a pregnancy test.

 

What are the symptoms of a chemical pregnancy:

The symptoms of a chemical pregnancy will most likely feel like your period.  For women who have symptoms,  they may experience some cramping and a little bleeding before the ‘main’ bleed within days of getting a positive pregnancy test result. Many women have chemical pregnancies without even knowing they were pregnant.

 

Do I need treatment for a chemical pregnancy:

No specific treatment is required for a biochemical pregnancy. The most important follow-up test is to ensure that the hCG levels decline to non-detectable levels in order to differentiate it from an ectopic pregnancy.

You should contact your doctor, however, with any bleeding following a positive pregnancy test. 

 

Who is at risk for a chemical pregnancy:

While the exact cause of a chemical pregnancy is unknown, most cases the miscarriage is due to problems with the embryo. At the time of conception, an egg and a sperm combine chromosomes (23 from each partner) to form a zygote, which begins to grow through rapid cell division. During that process, occasionally too many chromosomes or not enough will occur. These chromosomal abnormalities, which occur randomly and can happen to anyone, are believed to be behind most early pregnancy losses.
 

Being over the age of 35 increases the risk of a chemical pregnancy, as does certain medical problems. These include blood clotting and thyroid disorders.

 

What if I have multiple chemical pregnancies:

If you have three in a row, your doctor may want to run tests to rule out any medical problems that may be causing them. If a health condition is contributing to your chemical pregnancies, most can be treated so you can go on to conceive a healthy baby (source).

Some of the health conditions your doctor will screen for include:

  • abnormal hormone levels
  • uterine abnormalities
  • implantation outside the uterus
  • infections like chlamydia or syphilis

 

Are chemical pregnancies a sign of a problem:  

Chemical pregnancies are very common and are typically not at all an indicator that you won’t be able to get pregnant and stay pregnant in the future. As stated above, most chemical pregnancies and miscarriages are caused by chromosomal factors and there’s nothing you can do to prevent them.
 

Are Chemical Pregnancies considered a miscarriage:

Medically, a chemical pregnancy is more like a cycle in which a pregnancy never occurred than a true miscarriage, but they may be considered to be an early miscarriage by some. 

 

How common are chemical pregnancies:

According to ACOG, the American College of Obstetricians and Gynecologists, chemical pregnancies account for 50–75 percent of all miscarriages. In fact, it is believed to occur in 50-60% of first pregnancies, but often goes undetected.

 

On feelings after having a chemical pregnancy:

The excitement of seeing a positive pregnancy test and then learning that the pregnancy was not viable can lead to a deep sense of loss.

It is reported that many couples discontinue IVF treatment after experiencing a chemical pregnancy due to the disappointment. In fact, couples that had a negative test in the first place are found more likely to continue than couples who had a positive and then experienced a chemical pregnancy.  Among women who did continue to a second IVF cycle, those who had at least a chemical pregnancy on the first cycle, however,  were more likely to have a live birth on the second attempt than those women who had failed prior to conception in the first cycle (34% success rate compared to 21%, respectively) (source).

"One positive of a chemical pregnancy is that it can be regarded as being a “dark cloud that has a silver lining” because it offers the hope of a successful clinical pregnancy in the future," (source).

 

Can you prevent a chemical pregnancy:

Unfortunately, there are no known ways to prevent a chemical pregnancy.

It may help you to follow preconception guidelines to know that you are giving your body the best chance it’s got.  Keep in mind that there is nothing you can do to guarantee that a problem won't arise, but you can be assured that you are giving yourself and your baby the best chance you can.

 

Click here to learn more about what to do to prepare your body for pregnancy.

 

 

The American Pregnancy Association has a toll-free helpline at 1-800-672-2296 to speak with a pregnancy educator if you have further questions.

 

References and further reading:

  • http://www.healthline.com/health/pregnancy/chemical-pregnancy#4
  • http://americanpregnancy.org/pregnancy-complications/d-and-c-procedure-after-miscarriage/
  • https://www.acog.org/-/media/For-Patients/faq090.pdf
  • http://motherhow.com/chemical-pregnancy/
  • pregnancy.http://www.womens-health.co.uk/chemical.html
  • http://americanpregnancy.org/getting-pregnant/what-is-implantation-bleeding/