Chemical pregnancy: what is it and why does it happen?

A chemical pregnancy is a miscarriage that occurs in very early pregnancy. We look at how to spot chemical pregnancy, as well as the causes and what can be done to prevent it.

A chemical pregnancy is a miscarriage that occurs in very early pregnancy, most commonly in the first few weeks.

This type of miscarriage is called a chemical pregnancy because levels of the hormone human chorionic gonadotropin (hCG) are initially elevated enough to produce a positive result on a pregnancy test, but drop again before a doctor can see the gestational sac on an ultrasound.

According to the American College of Obstetricians and Gynecologists (ACOG), chemical pregnancies account for around 50 to 75 per cent of miscarriages. It is also thought to occur in as many as 50 to 60 per cent of first pregnancies.

One common theme with chemical pregnancies, according to Dr. Jeffrey Sternberg, founder of The Fertility Institutes, is that ‘many women fail to notice a chemical pregnancy, or tend to blame it on their menstrual cycle.’

In this article, we explore the signs and symptoms of chemical pregnancy, including what it looks like and how it can be prevented.

Signs and symptoms of chemical pregnancy:

The clearest sign of a chemical pregnancy is a positive pregnancy test result that is followed by a negative one.

Because chemical pregnancies occur so soon after implantation takes place, many women show very few symptoms, if any at all.

If women do experience symptoms, they may include:

  • mild spotting a week before an expected period
  • abdominal cramping, which is normally mild
  • vaginal bleeding that occurs close to the time of an expected period or shortly afterward.

A chemical pregnancy usually doesn’t require medical intervention or treatment, but women who experience one are encouraged to follow up with tests to ensure that their hCG levels return to normal.

chemical pregnancy

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Causes of chemical pregnancy:

It is not always possible to determine the exact cause of chemical pregnancies. Some potential causes or contributing factors may include the following:

  • Chromosomal abnormalities: These are the leading cause of early pregnancy loss. Irregularities in chromosomal arrangements may prevent the foetus from developing.
  • Uterine abnormalities: Presence of irregularities in the uterine lining can prevent the embryo from implanting in the uterus.
  • Insufficient hormone levels: The body needs higher levels of particular hormone, such as progesterone, to support the development of the foetus.
  • Low body mass index (BMI): Underweight women are more likely to have an early miscarriage.
  • Advanced maternal age: Women of 35 years or older may find it harder to get and stay pregnant.

What does a chemical pregnancy look like?

Chemical pregnancies are a type of miscarriage that differ from other miscarriages. While miscarriages can occur at any time during a pregnancy, a chemical pregnancy always occurs shortly after implantation. This could be within just days of getting a positive pregnancy result.

As the only symptoms, in many cases, are menstrual-like cramping and bleeding, some women simply think they’re having their menstrual cycle.

How long does bleeding last?

This depends on the individual. One woman may experience a miscarriage with bleeding and cramping that lasts a few hours, while another may have miscarriage bleeding for up to a week.

How can a chemical pregnancy be prevented?

Because most chemical pregnancies occur due to abnormalities in the chromosomes, there is nothing specific that can be done to prevent them. One vital step, however, is to lead a healthy lifestyle.

Monitor your lifestyle and focus on your health before conceiving to ensure pregnancy is occurring within as healthy an atmosphere as possible.

A few steps that can be taken include:

  • Eating a healthy, balanced diet
  • Eating iron-rich food
  • Avoiding smoking and excessive amounts of alcohol
  • Proper and regular exercise
  • Stress management
  • Monitoring weight and keeping it within healthy limits
chemical pregnancy

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There are a few extra things you can do once you realise you have conceived, to offer a healthy environment for your foetus to grow in. These steps include:

  • No smoking and drinking alcohol, and avoid being in a smoke environment
  • Consult your GP before consuming any over-the-counter medications
  • Avoid exposure to environmental hazards such as radiation, x rays and infectious diseases
  • Limit your caffeine intake
  • Avoid activities or contact sports that hold a risk of injury

Support after a chemical pregnancy:

Losing a child at any stage can cause a great deal of grief, anxiety and distress. If you’re having trouble coping with your loss, or know someone who is, then seek to speak to someone in the form of a doctor, counsellor or support group.

There are also many online support groups:

  • Miscarriage Association – has a pregnancy loss forum and private Facebook groups for people to safely discuss their miscarriage experiences and lend support to one another. You can also call their helpline which is open from 9am-4pm, Monday – Friday (01924200799)
  • Tommy’s – runs #MisCourage an online campaign which allows women to share their own stories of miscarriage. They also have a helpline ran by midwives who are trained in bereavement support, open from 9am-5pm, Monday – Friday (0800 0147 800)

It’s vital to remember that nobody is to blame for a chemical pregnancy, and in most cases they are totally out of the expectant mother’s control.

People with history of pregnancy loss can still go on to have healthy pregnancies and carry babies to full term with issues.

Have you had any experience with a chemical pregnancy, or know a loved one who has? Head over to our Facebook to share your story and lend support to other mothers.