In a normal, healthy pregnancy journey, sperm swim up through the vagina and fertilize an egg in the fallopian tube. If fertilization happens, the egg becomes an embryo that travels to the uterus. However, in rare cases, a molar pregnancy (hydatidiform mole) can happen when fertilization goes wrong. Instead of developing into a healthy embryo, the tissue grows into a noncancerous tumor. This condition is part of a group of disorders known as gestational trophoblastic diseases, involving abnormal growth of cells inside the uterus. 

What does a Molar Pregnancy Look Like?

The non-cancerous tumor in molar pregnancy looks like tiny water-filled sacs, similar to a cluster of grapes. 

Is Molar Pregnancy a Successful Pregnancy?

Unfortunately, a non-cancerous tumor can’t support a developing embryo, and the pregnancy ends. If this doesn’t happen, the doctor in Singapore may recommend surgery to remove the pregnancy. If left untreated, molar pregnancies can lead to serious complications.

Cryoviva Singapore (a private cord blood bank) says, if you are a new parent in Singapore ready to start the new phase of your life, you should be aware of every aspect of pregnancy, like types (ectopic pregnancy, molar pregnancy, and multiple pregnancy), how to maintain a healthy pregnancy, risk factors, hospital essentials for delivery, why to opt for cord blood or tissue banking, etc.

Let’s explore molar pregnancy in detail.

What Causes Molar Pregnancy?

The primary cause of molar pregnancy is genetic errors happening exactly during the fertilization of an egg by a sperm. 

In a normal pregnancy, an embryo receives one set of chromosomes (23) from each parent for a total of 46 chromosomes. Molar pregnancies contain an imbalance of chromosomes; sometimes, the embryo gets 23 chromosomes or 69 chromosomes from the sperm. This genetic error contributes to an unsuccessful pregnancy.

In short: 

• Abnormal fertilization due to a genetic error causes a molar pregnancy. This occurs when the fertilized egg has an abnormal set of chromosomes (fewer or more). 
• The abnormal chromosome number containing genes sends a message of abnormal growth of placental tissue that forms a mass or non-cancerous tumor instead of a normal embryo.

Types of Molar Pregnancy 

Molar pregnancies basically fall into 2 categories

• Complete Molar Pregnancy

There is no embryo formation. It occurs when a sperm fertilizes an empty egg. The egg contains no chromosomes. There are only 23 chromosomes from the sperm. There is 1 less set of chromosomes. 

• Partial Molar Pregnancy

It happens when an abnormal placenta develops along with an embryo. Two sperm fertilize one egg, and the embryo receives 69 chromosomes. There is 1 extra set of chromosomes.

Why it Feels Like I am Pregnant

In complete molar pregnancy, the placental tissue grows but is abnormal and composed of fluid-filled cysts. This placental tissue produces the pregnancy hormone HCG (human chorionic gonadotropin), making you feel like you’re pregnant. It can give you a positive pregnancy test.

Are There Any Symptoms of Molar Pregnancy 

A molar pregnancy might seem like a regular pregnancy at first because of the release of the pregnancy hormone HCG. Some individuals may not notice any symptoms. However, some of the symptoms are:

1. Dark brown to bright red bleeding from the vagina within the first three months
2. Severe nausea and vomiting
3. Grape-like cysts passing from the vagina
4. Pelvic pressure or pain
5. Preeclampsia (extremely high blood pressure), before 20 weeks of pregnancy
6. Abnormally high HCG levels
7. Ovarian cysts
8. Overactive thyroid
9. Abdominal swelling
10. Anemia

Note: These symptoms are very similar to other health conditions; hence, consult a healthcare professional for the precise diagnosis.

When do Symptoms of Molar Pregnancy Start?

Some women might not experience symptoms of molar pregnancy, but if they do, it typically starts during the first trimester, most commonly between 6 and 12 weeks of gestation.

Also Read: What Tests Should Be Done during Pregnancy?

How to Diagnose it Early

When you are pregnant, you should visit your doctor regularly so that conditions like molar pregnancy can be detected early. There are many diagnostic tests to detect abnormal tissue growth and hormonal changes; some of them are:

• Transvaginal or Abdominal Ultrasound (8–12 Weeks)

High-frequency sound waves are used to form an image of the uterus. If the image shows characteristics such as “snowstorm” or “cluster of grapes” patterns because of cystic placental tissue. This may help differentiate a molar pregnancy from a normal pregnancy.

• Checking HCG levels Via Blood Tests

The blood test helps measure the hormone human chorionic gonadotropin. If the level is abnormally high, then it may indicate a molar pregnancy.

• Histopathological Diagnosis

The tissue is removed from the womb under a microscope. If tissue shows swollen, fluid-filled structures called villi, and there is an overgrowth of the cells that normally form the placenta (known as trophoblasts). Then this can indicate a molar pregnancy.

• Complete mole shows no fetal tissue; all villi are swollen.
• Partial mole shows some normal villi and some swollen, with possible fetal tissue.
  
  

• Immunohistochemistry (Check p57KIP2 Marker)

It is a special lab test where laboratory professionals stain the tissue with a dye that attaches to a protein called p57. This protein is generally made only when there is genetic material from the mother. 

Complete molar pregnancies don’t have this maternal genetic material, so the stain for p57 is missing (negative). Partial moles and normal tissue have p57, so the stain shows a positive result.

Note: The doctors will confirm if the mole is complete or partial, which is crucial for managing the condition properly.

• Genetic/Cytogenetic Testing

Genetic or cytogenetic testing checks for the number of chromosomes in the tissue.

• A normal pregnancy contains 46 chromosomes.
• Complete molar pregnancy has 23 chromosomes.
• Partial molar pregnancy has 69 chromosomes.

This test helps your doctor decide the type of molar pregnancy for the right treatment and follow-up care.

• Clinical Evaluation

Symptoms such as early vaginal bleeding, abnormal uterine size, severe nausea, and possible ovarian cysts are evaluated by imaging and lab tests.

Various Treatments for Molar Pregnancy

Your doctor will decide the right treatment based on the laboratory and imaging tests. Some of the treatments that can be recommended are:

1. The primary treatment involves dilation and curettage (D&C) under general anesthesia to remove all abnormal tissue from your uterus.
2. Hysterectomy, or surgical removal (in very rare cases) of your uterus. It can be recommended if there is a high risk of cancer development or when future pregnancies are not desired.
3. Follow-up care involves monitoring your HCG levels until levels return to normal.
4. Additional treatment involves chemotherapy and preventive chemotherapy if hCG levels remain constantly high or there is a spread of other disease (gestational trophoblastic neoplasia).

Conclusion

In the beginning, a molar pregnancy might feel like a normal pregnancy, increasing the chances of ignoring this condition. That’s why you must go for regular follow-up and report any unusual symptoms so that your doctor can order medical tests for early detection, which ensures timely treatment and prevents complications.

In the case of normal pregnancy, many Singaporean parents are choosing to store cord blood for stem cell preservation to preserve their baby’s health against a potential 80+ diseases. Are you also ready to safeguard your family’s health? Then book an appointment with Cryoviva Singapore.