Cryptic pregnancy: symptoms, cause and advice

pregnant belly holding belly

by Emily Gilbert |
Updated on

We've all heard of those stories of women who given birth without knowing they were even pregnant, but did you know this is what's known as a cryptic pregnancy?

Dr Shazia Malik, Consultant Gynaecologist and Obstetrician at The Portland Hospital (part of HCA Healthcare UK), explains more.

What is a cryptic pregnancy?

A cryptic pregnancy is when a woman is unaware that she is pregnant until the later stages of her pregnancy, such as the third trimester, or sometimes even until she goes into labour and gives birth. This is sometimes referred to as a "stealth" or "denied" pregnancy.  It is rare though and occurs only in almost 1 in 500 pregnancies.

What are the symptoms?

By definition, a cryptic pregnancy is when a pregnancy is not detected. As a result, normal pregnancy symptoms such as exhaustion, nausea and vomiting, missed periods, or abdominal swelling may not occur, or the woman might assume that these symptoms are due to something else as she didn’t think of pregnancy as a possibility due to the reasons below.

However, this does not always imply that there are no indicators. It's possible that they're ambiguous enough that they're easily disregarded or mistaken for something else. For example, someone may mistake morning sickness as an upset stomach, or a missed period as an irregular menstrual cycle. Alternatively, other signs of pregnancy like foetal movement, minor weight gain, and fatigue could be dismissed as the result of dietary or lifestyle choices.

What causes a cryptic pregnancy?

There is no single explanation for a cryptic pregnancy. However, the following factors may have a role:

Lack of or misidentified pregnancy symptoms:  As mentioned, women may mistake common pregnancy symptoms for something else. The feeling and impact of different symptoms such as nausea, pelvic cramps, low back discomfort, and an enlarged abdomen can also vary from woman to woman and may be undetectable.

Irregular menstrual cycle: If you have irregular periods, it might be difficult to tell if you've missed a period. For someone who does not have a regular 28-day cycle, the absence of a period may not be an instant sign for pregnancy. Also, women who have PCOS, may experience hormonal abnormalities that disrupt ovulation. This can mean they’re unable to differentiate pregnancy symptoms from PCOS symptoms, and so could potentially result in an unanticipated pregnancy.

Intermittent spotting: Pregnancy-related bleeding and spotting might be mistaken for a mild menstruation.

No noticeable baby bump: A pregnant belly may not be visible to someone who is overweight or obese. It’s possible for some women to not gain much weight or start to show until later in their pregnancy.

• Age and fertility concerns: Pregnancy symptoms might be comparable to early menopause symptoms which could cause some confusion. If you've also previously suffered from infertility, you may assume that you can’t get pregnant and therefore attribute the symptoms or physical changes to something else.

Low body fat and athletic activity can cause your period to disappear for months at a time. People who participate in high-impact sports may also have low levels of certain hormones, making it harder to detect pregnancy or realise that they are in fact pregnant.

•Sometimes teenagers can have a cryptic pregnancy as they do not know the symptoms of pregnancy, or their periods were not regular, or they are too frightened to share it with an adult or seek help.

• There are times when a pregnancy is undetected because the person carrying the pregnancy can’t acknowledge the pregnancy. These cases can be impacted by chronic mental illness or outside factors, like an abusive partner or an unsupportive family who would not accept the pregnancy.

How can a pregnancy test be negative if you’re pregnant?

When using a home pregnancy test, it is possible to obtain a negative result even if you are pregnant. This is referred to as a false-negative. Pregnancy tests are usually quite accurate, although errors can sometimes happen.

It is important to follow the instructions properly. Typically, a positive test result is nearly always accurate. A negative test result, on the other hand, is less dependable. If you did not follow the directions correctly or take the test too soon, the results may be unreliable. Some medications can also have an effect on the result, so make sure to double-check with your doctor or pharmacist about any medicines you're taking at the time.

It should also be noted that pregnancy tests are most accurate on the first day or week of your missed menstruation. As the pregnancy hormone levels rise and the pregnancy progresses, a test can be falsely negative just because the levels are too high for the test to work properly.

If you get a negative test but still believe you're pregnant, wait a few days before trying again. Speak with a consultant if a second test has a negative result and you have still not started your period when you were expecting to. They can organise an ultrasound scan to check.

What is the pregnancy experience like for a cryptic pregnancy?

All pregnancies differ from one person to the next. Symptoms of a cryptic pregnancy might be similar to those of a normal pregnancy, such as nausea, vomiting, back pain, exhaustion, headaches or migraines, or changes in appetite and taste.

Pregnancy weight gain is common but depending on how the foetus is positioned or how a woman’s own body weight is distributed, a person may not display a noticeable baby bump. In a cryptic pregnancy, the foetus may grow at a slower rate than typical, causing them to be undeveloped in the womb, but most commonly the pregnancy will develop normally.

Unfortunately, though, both the woman and her baby will miss out on important tests and support which can make the pregnancy higher risk.

What is the labour experience like for a cryptic pregnancy?

The labour experience of a cryptic pregnancy will be physiologically comparable to any other pregnancy. Contractions that feel like severe cramps are common while your cervix stretches to allow you to birth the baby. Your body will need to push the baby out of the delivery canal after your cervix has dilated.

What makes labour unique for a cryptic pregnancy is that you may not be anticipating it at all, which can cause intense psychological distress whilst giving birth.

What should I do if I think I’m having a cryptic pregnancy?

Firstly, you should seek medical advice from a gynaecologist to find out if you are pregnant, or if there is another issue.

It’s very possible to have a healthy baby even if you’re not aware that you’re pregnant until the later stages of the pregnancy. However, it’s important that you seek medical attention to check on the health of the baby as soon as you’re aware you are pregnant.

When a woman does not know she is pregnant, she may have consumed substances such as alcohol, tobacco, or certain medication, which can be harmful to the baby, and so it’s important for a full check-up to be carried out by your gynaecologist.

Also, a baby born from a cryptic pregnancy could be underweight or born prematurely, so it may need urgent medical care at the early stages of its life.

This can understandably be a stressful and overwhelming experience, so it’s important to keep a check on your own physical and mental health. Alleviating stress in the mother can also be helpful in avoiding stress on the baby.

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