Molar pregnancy is caused by genetic problems by fertilizing an egg with sperm. After the sperm fertilizes the egg, new tissues are formed that normally form the placenta and embryo.
Molar pregnancy is also known as the trophoblastic disease of pregnancy. The tissue that was supposed to form the placenta grows abnormally and can form a tumor that spreads inside or outside the uterus. Most women are treated and can have a healthy pregnancies in the future.
What is a molar pregnancy?
Molar pregnancy (also called a hydatidiform mole or HM) is a pregnancy in which the placenta does not form properly. Instead, it turns into small bags full of fluid and cannot provide food and oxygen to the baby like a healthy pregnancy. The result of molar always is pregnancy loss. About one in every 1,000 pregnancies in the United States is a molar pregnancy.
Types of molar pregnancy
These types of pregnancies may be partial or complete. In partial mole, two sperm lay an egg instead of one. There is too much genetic material for a fetus to grow. In a complete mole, one or even two sperms fertilize an egg cell that contains no genetic material. There are not enough suitable chromosomes for a fetus to grow.
The molar cells sink too far into the uterus in very few cases. These cells can become cancerous and spread to other parts of the body. This condition is called an invasive mole.
Causes
It is unclear exactly what causes this type of pregnancy, but some things increase the risk.
- Age: Molar pregnancies are more common in women who become pregnant during adolescence and women over 45.
- Previous molar pregnancy: If you have had a molar pregnancy before, the chance of having another hydatidiform mole is about 1 in 80, while in women who have not had this type of pregnancy before, it is 1 in 600, and if you have had two or more hydatidiform moles, the risk is about 1 in 5.
- Ethnicity: Asian women are almost twice as likely to have a molar pregnancy.
- Low carotene and folic acid intake: Women who do not get enough beta-carotene (vitamin A) and folic acid are more likely to have a full-molar pregnancy. Of course, you should not take any other vitamin A supplement. Too much vitamin A can harm a fetus. The best thing you can do to ensure you get all the necessary vitamins and minerals is a healthy, balanced diet.
Symptoms
Molar pregnancy usually has no specific symptoms. It can be diagnosed by an ultrasound scan at 4 to 14 weeks of pregnancy or by a blood test after a miscarriage. Some pregnant women have the following symptoms:
- Vaginal bleeding or a dark discharge from the vagina in early pregnancy
- Severe morning sickness
- Pelvic pressure or pain
- Grape-like cysts that come from your vagina
Some of these symptoms are also common in normal pregnancies and are not necessarily signs that you have a problem with your baby. Try not to worry and consult your obstetrician. Symptoms that are less common in molar pregnancy and are diagnosed by a doctor include:
- High blood pressure
- Stomach pain
- Hyperthyroidism
- Anemia
- The uterus grows too much or too little
Treatment
This kind of pregnancy does not lead to the birth of a baby and must be treated. Different treatments depend on the mother’s condition and the doctor’s diagnosis.
Dilation and curettage
The doctor eliminates molar pregnancy by dilating the cervical cleft and using a medical vacuum to remove harmful tissue. Anesthesia is performed before curettage and is usually performed in a hospital as a surgical procedure.
Chemotherapy drugs
If the pregnancy is high-risk because of the potential for cancer, chemotherapy may be prescribed after curettage.
Hysterectomy
Hysterectomy is a surgery that removes the entire uterus. If you do not decide to become pregnant, you can choose this option, but a hysterectomy is not a common treatment for a molar pregnancy.
Once the molar pregnancy is over, you will need more testing and monitoring.
Monitoring after treatment
Some abnormal cells may remain in the uterus after treatment. They usually leave alone within a few months, but sometimes more treatment may be needed to eliminate them. To ensure no further treatment is needed, regular blood or urine tests are done to measure the level of the hormone hCG (human placental gonadotropin).
The level of this hormone increases during pregnancy. If the hormone level does not decrease after treatment, it may mean that some abnormal cells remain in the uterus.
What to expect after the operation?
The following may occur after curettage:
- Tiredness: You will probably feel tired 24 hours after the operation and should avoid drinking alcohol, driving, or operating dangerous machinery.
- Bleeding: The bleeding is usually less than one period and should stop within one to two weeks. Tell your doctor if the bleeding still does not stop after two weeks, the bleeding was too much, or it smelled very bad.
- Pain: After the operation, you may have mild pain in the lower abdomen. This is normal for a few days.
- Hygiene: If the bleeding continues, using a sanitary pad instead of a tampon is best to reduce the risk of infection. If necessary, you can take a bath or shower.
- Breasts: Breasts may be tender for several days, and you may even leak milk from them. Wear a comfortable bra. Use a weak painkiller if it is very painful.
Prevention
If you have had a molar pregnancy, talk to your doctor before becoming pregnant again. It may be advisable to wait six months to a year before getting pregnant. During subsequent pregnancies, your obstetrician may perform initial ultrasounds to monitor your condition and ensure normal growth. It may also discuss prenatal genetic testing, which can be useful in diagnosing molar pregnancy.
Is there a chance of getting pregnant again?
There is a chance of getting pregnant again and having a healthy baby. It is good not to get pregnant until all treatment steps are completed. For most women, the time is about six months. If chemotherapy is needed, you will have to wait 12 months after the end of the chemotherapy treatment because, in rare cases, the cancerous tissue may return.
Contraceptive methods such as condoms or diaphragms should be used until hCG levels are normal. You should not install an intrauterine device until your hCG level is normal. This is because it can cause uterine perforation after a molar pregnancy.
More information and support
Emotional recovery from molar pregnancy can be time-consuming. These strategies can be helpful, including:
- Talk about how you feel about your partner, family, or friends
- Ask your care team what support is available. Psychological counseling may help you get through this period more easily
- Read tips for coping with grief
The experience of molar pregnancy can be very upsetting. Not only did you lose the baby, but you also needed medical attention to check your hCG levels, which meant having a long period of anxiety. Molar pregnancy is uncommon but can occur in women of all ages and with different conditions. This type of pregnancy is a long and emotionally frustrating experience. Treatment and counseling can help expect a healthy pregnancy and baby in the future.
Additional questions
- What percentage of molar pregnancies are cancerous?
Less than 15% of molar pregnancies become invasive and spread outside the uterus.
- How many weeks does a molar pregnancy last?
In a complete molar pregnancy, the fetus does not grow, but the placental tissue grows rapidly. It is very abnormal and forms many cysts. A complete molar pregnancy usually miscarries between 16 and 18 weeks.
- Can molar pregnancy be treated with medicine?
After a molar pregnancy is diagnosed, the molar tissue must be removed from the uterus. Some women with partial molar pregnancies are treated with medication that shrinks the uterus and removes the abnormal cells.
- What are the nine types of pregnancy?
- Intrauterine pregnancy
- Ectopic pregnancy
- Tubal pregnancy
- Intra-abdominal pregnancy
- Singlet pregnancy
- Multiple pregnancies
- Lupus pregnancy
- High-risk pregnancy
- What is a natural pregnancy?
It is measured in weeks from the first day of the woman’s last menstrual cycle to the current date. A normal pregnancy can be between 38 and 42 weeks. Babies born before 37 weeks are considered premature. Babies born after 42 weeks are considered post-mature.
References
https://www.mayoclinic.org/diseases-conditions/molar-pregnancy/symptoms-causes/syc-20375175
https://my.clevelandclinic.org/health/diseases/17889-molar-pregnancy
https://www.pregnancybirthbaby.org.au/molar-pregnancy
https://americanpregnancy.org/healthy-pregnancy/birth-defects/molar-pregnancy/
https://www.betterhealth.vic.gov.au/health/healthyliving/pregnancy-related-cancer