Cryptic Pregnancy: What it is - and why it happens

Health & Fitness

Cryptic Pregnancy: What it is - and why it happens

Cryptic - or stealth - pregnancies are more common than you may think, but what are they? What causes them? And what are the symptoms?

We’ve all heard the stories; a woman goes into hospital with stomach pains and comes out with a baby. And, if you’re anything like us, you’ll have wondered aloud how she didn’t realise that she was pregnant.

But it’s not because they’re in denial, or because they don’t know how sex works.

In fact, their experiences are a product of what is known as a “cryptic pregnancy” - when a woman doesn’t find out that she’s pregnant until 20 weeks along or later - which affects 1 in 450 women.

What is a cryptic pregnancy?

It is a pregnancy where there is little or no detectable hCG (human chorionic gonadotropin) in the mother’s system.

This is the hormone that makes a home pregnancy test turn positive. A baby that produces a scant amount amount of HCG might go "under the radar," failing the pregnancy test and going undetected by the mother.

What causes a cryptic pregnancy?

It appears that cryptic pregnancies occur when women suffer from a hormonal imbalance.

This can be due to:

  • Polycystic Ovarian Syndrome (PCOS).

  • Perimenopause (which can begin as early as age 30)

  • A recent pregnancy (hormones may not have time to go back to normal before falling pregnant again)

  • The woman is still breastfeeding

  • The woman has a very low body fat percentage

  • The woman has recently used, or is currently using, a birth control method such as the "Norplant", "Deprovera" Injection or the "Mirena Coil", that continually releases hormones into the body.

According to some doctors, a cryptic pregnancy can also be caused when the woman is simply stressed out. Apparently, in this case, it's in the foetus's best interest for the mother to be happily oblivious to the fact that she's pregnant.

Why? Well, sometimes, the normal stresses of a pregnancy combined with other stresses in a mother's life can lead to miscarriage. But a 'stealth' pregnancy that uses few resources in a mother's body can actually increase the foetus's chance of survival.

Bleeding or continued periods during a crypic pregnancy

A vast majority of the women who go through a cryptic pregnancy will continue to have some sort of "period-like" bleeding through the entire pregnancy.

Because she will continue to bleed throughout the entire pregnancy, the hCG is never allowed to build up and secrete into the urine or blood, because some of it is shed every time she bleeds.

This is the cause of so many negative pregnancy tests.

Weight gain or weight loss during a cryptic pregnancy

Some women going through a cryptic pregnancy will gain weight gradually - and (depending on the position of the foetus) not necessarily in a neat bump.

Others, due to food aversion, may lose weight during the first few months.

Signs and symptoms of a cryptic pregnancy

According to the Cryptic Pregnancy Support Group, many women going through a cryptic pregnancy will experience the typical symptoms of pregnancy.

These may include:

  • Nausea/vomiting

  • Fatigue

  • Frequent urination

  • Food aversion

  • Increased appetite

  • Weight gain

  • Heart burn

  • Back pain

  • Metallic taste in mouth

  • Abdominal cramping/round ligament pain

  • Headaches

These symptoms will vary in severity for each individual.

Women going through a cryptic pregnancy may also suffer from the following symptoms:

  • Negative urine and blood pregnancy tests

  • Continued periods

  • Weight loss (this can also occur in a "standard" pregnancy)

  • Early labor signs that occur off and on for weeks or even months (not preterm labor)

  • An extended gestational period

  • Slow growth of the abdomen/pregnant belly

The pregnancy symptoms may come and go. You may not "feel" pregnant all the time. Frequently during the periods, the pregnancy symptoms will subside.

What to do if you think you may be going through a cryptic pregnancy

If you are experiencing some pregnancy symptoms but not others, or even if you just “don’t feel right,” you should make an appointment to see your doctor as soon as possible.

Visit the Cryptic Pregnancy Support Group to find out more.


Dr Christian: ‘You CAN be pregnant with absolutely no symptoms at all’

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