Molar pregnancy

Question 1

What is a hydatidiform mole?

Answer 1

• type of tumour that grows like a pregnancy inside the uterus
• this is called a molar pregnancy
• two types of molar pregnancy: complete and partial mole

Question 2

What is a complete mole?

Answer 2

• when two sperm cells fertilise an ovum with no genetic material and then combine genetic material resulting in the cells dividing and growing into a tumour called a complete mole
• no fetal matter forms

Question 3

What is a partial mole?

Answer 3

• when two sperm cells fertilise a normal ovum containing genetic material at the same time
• new cell formed now has three sets of chromosomes (haploid cell_ and so divides and multiplies into a tumour called a partial mole
• some fetal matter may form

Question 4

What signs and symptoms can differentiate a molar pregnancy from a normal one?

Answer 4

• more severe morning sickness
• vaginal bleeding
• increased enlargement of the uterus
• abnormally high hCG
• thyrotoxicosis as hCG can mimic TSH

Question 5

What would a pelvic US show in a molar pregnancy?

Answer 5

• characteristic “snowstorm” appearance (cluster of grapes) of the pregnancy (only in complete)

vs incomplete: no snowstorm / ‘cluster of grapes’, just foetal parts

- diagnosis can then be confirmed with histology of mole after evacuation

Question 6

What does management of a molar pregnancy involve?

Answer 6

• evacuation of the uterus to remove the mole
• histological examination to confirm molar pregnancy
• Patients should be referred to the gestational trophoblastic disease centre for management and follow up
• hCG monitored until normal
• Occasionally the mole can metastasise, and the patient may require systemic chemotherapy.

Question 7

what are some RFs for hydatiform mole

Answer 7

1. previous molar pregnancy
2. extremes of age
3. race; an increased rate of molar pregnancy is seen in people from South East Asia,

Question 8

what other conditions commonly co-exist in molar pregnancy:

Answer 8

Pre-eclampsia, thyrotoxicosis and hyperemesis gravidarum are common in molar pregnancy.

Question 9

Symptoms/diagnosis of molar pregnancy:

Answer 9

Molar pregnancy behaves like a normal pregnancy. Periods will stop and the hormonal changes of pregnancy will occur. There are a few things that can indicate a molar pregnancy versus a normal pregnancy:

1. More severe morning sickness
2. Vaginal bleeding
3. Increased enlargement of the uterus
4. Abnormally high hCG ( often significantly higher than would be expected in an early pregnancy)
5. Thyrotoxicosis (hCG can mimic TSH and stimulate the thyroid to produce excess T3 and T4)

-Ultrasound of the pelvis shows a characteristic “snowstorm appearance” of the pregnancy.
-Due to the size of theca lutein cysts, the ovaries are often enlarged.

-Provisional diagnosis can be made by ultrasound and confirmed with histology of the mole after evacuation.

Question 10

where does choriocarcinoma metastasise to?

Answer 10

Choriocarcinoma (A) is also a form of gestational trophoblastic disease, but it is aggressive and malignant. It readily metastasizes to the lungs.