Cryptic Pregnancy: Causes, Signs And Duration

Cryptic Pregnancy

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One in 450 pregnant women don’t even know they are pregnant until they reach 20 weeks of pregnancy (1), and one in 2,500 don’t know they are pregnant until they reach labor. This mysterious pregnancy is called cryptic pregnancy or stealth pregnancy.

MomJunction helps you go deep into this mysterious phenomenon, as we explain why cryptic pregnancy happens, how you can recognize it and deal with it.

What Is A Cryptic Pregnancy?

A cryptic pregnancy is one that goes undetected or unnoticed until delivery. It refers to a medically defined condition called ‘denial of pregnancy’ (2). This means that you are pregnant, but the human chorionic gonadotropin (hCG) levels are too low to be detected in a blood or urine test.

Cryptic pregnancies usually occur in women who have been on birth control methods such as contraceptive pills, IUCD, tubal ligation (tubes tied to prevent the sperm from entering the fallopian tube), etc. These women come under the ‘least expected pregnancy category’ and experience common pregnancy symptoms such as fatigue and morning sickness mildly, or do not experience anything at all. These symptoms are mistaken as those of some other condition.

What Causes Cryptic Pregnancy?

Several hormonal and psychological reasons can lead to cryptic pregnancy. However, the psychological causes are lower than the hormonal.

  1. Polycystic ovarian syndrome (PCOS): Small cysts form on the enlarged ovaries. Women may have irregular or prolonged cycles due to hormonal imbalance.
  1. Recent pregnancy: Hormones may take time to get back to normal after your pregnancy. Recent childbirth and lactation may cause amenorrhea and women might not know when they started ovulating again. If you are pregnant immediately, there would be hormonal imbalance causing a cryptic pregnancy.
  1. Low body fat could trigger a hormonal imbalance as in the case of athletes.
  1. Perimenopause is the time when the body starts showing up signs of progression to menopause, leading to irregular cycles. It can start as early as in the 30s, making the pregnancy go unidentified.
  1. Birth control pills such as Deprovera, Norplant, or Mirena Coil release more hormones which affect the normal pregnancy hormones making them vulnerable to pregnancy.
  1. High-stress levels can cause a cryptic pregnancy as they influence the hormones.

[Read: PCOS And Pregnancy Symptoms]

What Is The Duration Of Cryptic Pregnancy?

There is no evidence to determine the duration or the gestation period of cryptic pregnancy. That’s mainly because the woman might not know when the pregnancy started, how long it may go, and when it would end. However, it is said that a cryptic pregnancy lasts longer than the normal pregnancy as the development is slower. But this is not based on any research or study.

Sometimes, there could be regular periods during a cryptic pregnancy due to partial shedding of the endometrial lining. Even in such a case, it becomes difficult to determine the duration. Some cryptic pregnancy cases that have been reported were shorter than normal pregnancy, while some were longer. Hence, the duration is uncertain.

Even when the pregnancy is cryptic, it could send you some signals.

Cryptic Pregnancy Symptoms

The symptoms of cryptic pregnancy are similar to a regular pregnancy. Note that the symptoms vary from one woman to the other.

  • Nausea
  • Vomiting
  • Fatigue
  • Food aversions
  • Frequent urination
  • Weight gain
  • Heartburn
  • Headaches
  • Abdominal cramps
  • Backache
  • Metallic taste in the mouth

The symptoms could be similar to those of normal pregnancy. So, how is cryptic pregnancy different from the normal?

Why Is Cryptic Pregnancy Cryptic?

Pregnancy remains a secret because of these reasons:

  • You may have regular periods throughout the pregnancy due to partial shedding of the endometrial lining, though the number of bleeding days may be less. Spotting and bleeding due to implantation could be mistaken for a regular period.
  • Urine and blood tests and ultrasound show negative.
  • Slow pregnancy belly growth as baby is at the back of the womb (at the spine).
  • Fetal movements inside the womb are mistaken for gas and bloating.

What Happens To The Fetus In Cryptic Pregnancy?

In cryptic pregnancy, the development of the fetus is delayed and interrupted frequently, taking place at an extremely slow pace. But this does not necessarily affect the health of the fetus. The mother would go to hospital only when she has severe stomach and back cramps, that is, during labor.

How Can Pregnancy Go Undetected After Missed Periods?

Not all women have regular and monthly periods and a missed period may not bother them. Even if periods occur occasionally, spotting during pregnancy may be construed as menstrual bleeding. The irregular or less flow could be attributed to stress, menopause, or other health problems.

Continued Periods/Bleeding In Cryptic Pregnancy

Most women continue getting their regular periods throughout the cryptic pregnancy, but this does not indicate a miscarriage. It can be heavy, light, or spot bleeding with a few large or small clots. The bleeding can be bright red, pink, brown, purple, orange, or black. It can be like a normal period, sporadic or random. The bleeding could sometimes last for weeks or months, but all it does is shed away the uterine lining. This results in little or no hCG.

How Is A Negative Test Result Possible?

In a normal pregnancy, the pregnancy test shows negative if it is taken too early or if you fail to follow the instructions correctly.

But in a cryptic pregnancy, the result is negative because the level of hCG is negligible. The placenta usually secretes hCG, which passes along the lining of the uterus. It builds up and is shown in the urine and blood. In cryptic pregnancy, the lining of the uterus sheds periodically without giving hCG the scope to build up and show up in tests.

Moreover, if you are not anticipating a pregnancy, you would not take the test.

[ Read: Reasons Of False Negative Pregnancy Test Result ]

How Does Cryptic Pregnancy Go Undetected In Ultrasound?

In a normal pregnancy, the doctor will do a trans-vaginal ultrasound 12 weeks into the pregnancy. After that, she will do an abdominal ultrasound until the due week.

However, in most cryptic pregnancy cases, ultrasound scans cannot detect the growing fetus in a majority of women. This may be due to some abnormalities in the abdominal region or uterus.

  1. Uterine retroversion: It is also known as tipped or tilted uterus because the uterus is inclined towards the back of the pelvis unlike a vertical position (as in a normal uterus). This position makes it difficult to see the fetus in an ultrasound during early gestation. Retroversion happens due to one of the below reasons:
  • The uterus does not move to the posterior position during puberty. .
  • The growing baby stretches the ligaments, repositioning the uterus from its original place.
  • Endometriosis (endometrium grows outside the uterus) or fibroids (non-cancerous growths in the uterus) can cause scarring, which will move the uterus to the anterior position.
  1. Bicornuate uterus: It is a congenital abnormality wherein the uterus is heart-shaped, with two horns [3]. A wall splits the uterus either completely or partially. It can thus affect the reproductive abilities of a woman, and also result in cryptic pregnancy.
  1. Abnormal scar tissue: An abnormal scar tissue can happen due to abdominal surgery, C-section, or tummy tucks, among others. This scar tissue prevents the ultrasound waves from passing into the uterus, showing negative results on the scan.

Why Does Cryptic Pregnancy Have Longer Gestational Period?

The HCG will not pass into the maternal system as in a typical pregnancy. This prevents the body from generating signals essential for baby development. The fetus will thus grow slowly. The babies measure smaller than they should be at various pregnancy phases.

Also, regular periods during cryptic pregnancy prolong the gestational period. The heavier the period bleeding, the longer is the gestation.

Possible Complications Of Cryptic Pregnancy

There would not be prenatal care as you are not aware of your pregnancy. The delivery, thus, turns out be unassisted or at home.

  • Prenatal complications such as hypertension, diabetes, or blood group incompatibility will go undetected putting both the mother and baby at risk.
  • The mother may not avoid certain habits such as smoking or drinking.

Cryptic Pregnancy Labor

Just like cryptic pregnancy, its labor is also strange. It is long and protracted, and you will experience labor like pains for months before you enter into actual labor. The labor pains, which may initially seem like menstrual cramps, will get worse and hurt a lot more. This, coupled with the pains lasting for months, may prompt women to see a doctor, where the pregnancy may be confirmed. The doctor may try to induce labor or perform a C-section to deliver the baby.

Some of the labor symptoms in cryptic pregnancy are:

  • Back pain
  • Nausea
  • Vomiting
  • Hot flashes
  • Chills
  • Dizziness
  • Cold sweats
  • Diarrhea
  • Body ache
  • Pain in the legs that radiates to the thighs
  • Mood swings
  • Pain in the hip and pelvic region
  • Palpitations
  • Swelling of the vaginal walls due to increased blood flow
  • Painful breasts. Sometimes, the pain can be shooting, sharp pain
  • Pressure on the cervix
  • Stabbing pain in the sides, just like you get after running
  • Tugging or pulling sensation in the abdomen which may or may not be painful

You may experience all or a few of these symptoms that can stretch for months. In most cases, the actual process of cryptic pregnancy delivery is very quick and does not last long.

You may experience back pain or a tightness which radiates to the front like that of a period pain. You may want to go to the loo but would not have a bowel. In such a case, go to a hospital.

Real Stories Of Cryptic Pregnancy

Although the case of cryptic pregnancy is rare, there are some surprising stories.

  • A week before turning 18, Beth complained of experiencing severe cramps. She went to the hospital where she was asked if she was pregnant. She said she had taken pregnancy test a few weeks before, the result of which was negative. After that, she was not involved in sex. After reaching the hospital, she delivered a healthy full-term baby.
  • Klara Dollan, then 22, started her day by going to the office. She had intense stomach cramps, so she left her workplace and reached home. The cramps were turning bad with every minute. Her neighbor arrived and called the ambulance. Until the ambulance came, she started bleeding and then delivered a baby. After reaching the hospital, she was told that it was a case of cryptic pregnancy.
  • Charlotte Thomson had a flat stomach and regular periods. After a week of the office party, she had pains and was admitted to the hospital. The doctor noticed bleeding and said she is in labor. And then she delivered a healthy baby girl, who was named Molly.

How To Prevent Cryptic Pregnancy?

During the reproductive age, if you are continuously experiencing certain pain or changes in the abdomen or pelvis, you should immediately see a doctor. Though it is difficult to detect a pregnancy, your doctor might make a guess about it.

If you do not get regular periods, take repeated pregnancy tests. You should speak to your gynecologist about irregular periods and get a thorough checkup. You should also get a checkup done if you think you have entered menopause.Cryptic pregnancy doesn’t seem real or at least we don’t see such things happening around us.

Frequently Asked Questions

1. How will the cryptic pregnancy baby movement be?

The feeling of fetal movements in cryptic pregnancies is like that of gas or irritable bowel syndrome. When you feel your bowels and abs moving, you misinterpret them to be due to worms, cysts, constipation, fibroids, or muscle spasms.

2. How long does a cryptic pregnancy last?

As the babies develop at a slower pace, a cryptic pregnancy can last for more than 40 weeks.

3. How to confirm a cryptic pregnancy?

Since cryptic pregnancy cannot be detected through blood or urine tests, or an ultrasound scan, your practitioner may use a Doppler (monitors fetal heart rate) (4) along with a finger pulse (5) to confirm the pregnancy.

Cryptic pregnancy can put a woman in a tough position, especially if she is unprepared to look after a baby. A woman has to be mentally, emotionally, and physically prepared to bring a baby into the world and nurture it.

If you have irregular periods and the test results show otherwise, talk to a gynecologist. Also, take care of yourself and eat healthy to promote a normal and healthy development of your baby.

Have an experience to share? Let us know in the comment section below.

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