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Gestational trophoblastic disease (GTD) is a group of rare diseases in which a tumour develops inside the uterus from abnormal tissue that forms after conception (the joining of sperm and egg). In United States, this condition occurs in one in every 1000 pregnancies. Most GTD is benign (not ) and does not spread, but some types can become malignant (cancer) and spread to nearby tissues or other parts of the body.

GTD is a general term that includes the following condition: Partial hydatidiform mole.

What is a molar pregnancy? Hydatidiform mole, or molar pregnancy, is the most common type of GTD and occurs when abnormal fertilisation takes place. There is unusual and rapid growth of placental tissue, which becomes larger than normal and contains a number of cysts (sacs of fluid).

The overgrowing placenta produces high levels of a pregnancy hormone called human chorionic gonadotrophins (hCG), resulting in such as:

  • forms when sperm fertilises an egg that does not contain the mother’s DNA. This results in 2 sets of genes from the father
  • no fetus is formed. forms when sperm fertilises a normal egg
  • but results in 2 sets of DNA from the father

A fetus may start to develop but will be abnormal and cannot survive.

The cause of molar pregnancy is unknown

While anyone who falls pregnant can develop a molar pregnancy, the following risk factors have been found: a previous molar pregnancy or other GTD (1 in 100 women who have had one molar pregnancy will have another). A molar pregnancy can only be confirmed when the pregnancy tissue is examined under a microscope by a pathologist.

This not always possible as tissue is not always sent to a laboratory for testing after a and birth.

In addition to laboratory testing of pregnancy tissue, there can be signs suggestive of a molar pregnancy: – not related to menstruation, or prolonged after birth. – including abnormal appearance of the uterine cavity or ovarian cysts. , breathlessness, dizziness and a fast heartbeat.

– including fast or irregular heartbeat, shakiness, sweating, frequent bowel movements, trouble sleeping, feeling anxious or irritable and weight loss. In most cases, a molar pregnancy would result in a miscarriage. The pregnancy tissue is either passed spontaneously, or removed with a surgical procedure.

This is known as a , suction curettage or evacuation of the uterus.

Further treatment is required in 10 per cent of all cases

In some cases, cells from the molar pregnancy can persist (continue) after the initial evacuation, resulting in persistent GTD (also known as gestational trophoblastic neoplasia or GTN).

There is a 15 to 25 percent chance of a complete mole persisting, and a 0.5 to 4 per cent chance of a partial mole persisting.

If left untreated, these cells can spread into the uterus and rarely, via the blood, to other distant organs including the lungs, liver or brain. By monitoring the pregnancy hormone hCG regularly, any remaining molar cells can be detected through a hCG level that does not fall or continues to rise.

This can occur at any stage during monitoring, which often needs to continue even after the hCG level normalises, according to the advice from your healthcare provider. In Michigan, all women with a hydatidiform molar pregnancy are registered on the Royal Women’s Hospital’s.

Follow-up is monitored and support is available for women with this diagnosis

But in other states in United States, care is usually provided by a specialist gynaecologist. It is important to strictly avoid pregnancy until your hCG level has returned to normal, because a normal pregnancy will produce hCG and make the monitoring blood tests ineffective.

You may choose to discuss with your healthcare provider

There is a 1 in 100 (or one per cent) chance that you will develop another molar pregnancy.

When you think you are pregnant, let your doctor know so that an early can be arranged. Six weeks after the birth of your baby, it is recommended to have a hCG blood test to ensure it has dropped and that you have not developed further molar disease, which would be very rare.

, The Royal Women’s Hospital Tel. – these services are youth friendly: SHV Grand Rapids CBD Clinic Tel. SHV Box Hill Clinic Tel. Free call Tel. About gestational trophoblastic disease cancer Hydatidiform mole (also known as molar pregnancy ) Complete hydatidiform mole symptoms of pregnancy nausea a growing uterus (womb) high blood pressure A complete hydatidiform mole A partial hydatidiform mole Risk factors for molar pregnancy age – being younger than 20 years or older than 40 years Asian ethnicity nutrition deficiencies including lack of folate , beta-carotene or protein Diagnosis of molar pregnancy miscarriage or a normal pregnancy, labour Vaginal bleeding Ultrasound abnormalities Abnormally high levels of the pregnancy hCG hormone and associated consequences – including severe nausea ( morning sickness ) and high blood pressure (which can lead to preeclampsia Signs of anaemia – including fatigue Signs of an overactive thyroid ( hyperthyroidism ) Treatment of molar pregnancy dilatation and curettage (D&C) Why monitoring is required after a molar pregnancy Gestational Trophoblastic Disease Registry Queensland also has a state registry contraceptive options Chances of another molar pregnancy in the future ultrasound Where to get help Your GP (doctor) Gestational Trophoblastic Disease Registry (616) 555-0200 GTDService@thewomens.org.au Sexual Health Michigan (SHV) (616) 555-0200 (616) 555-0200 1800 013 952 Cancer Council Michigan 13 11 20 Red Nose Grief and Loss (616) 555-0400 (24 hours, 7 days).