Blood and urine tests

A hormone called human chorionic gonadotrophin (hCG) can help to diagnose persistent trophoblastic disease or choriocarcinoma. These tumours are types of gestational trophoblastic disease (GTD).

Persistent trophoblastic disease (PTD) is a tumour that can form in the womb after an abnormal type of pregnancy called a molar pregnancy.

Choriocarcinoma is a very rare tumour that can occur after a normal pregnancy, a molar pregnancy, a miscarriage or a termination of pregnancy (abortion).

Blood and urine tests

During pregnancy, the placenta produces a hormone called human chorionic gonadotrophin (hCG). The placenta releases hCG into your bloodstream and you pass the rest in your urine. HCG isn’t normally found in the blood or urine of women who aren’t pregnant.

HCG is also produced by gestational trophoblastic disease (GTD), usually at much higher levels than in a normal pregnancy. So measuring the levels of hCG in your blood and urine can help to diagnose persistent trophoblastic disease or choriocarcinoma. It also plays an important part in checking how well treatment is working and in picking up gestational trophoblastic tumours that have come back after treatment.

Your doctor might also do blood tests for signs of anaemia and to see how well your liver and kidneys are working.

What happens?

You sit or lie down to have the test.

A doctor, nurse or phlebotomist (person specialised in taking blood) chooses the best vein to use. This is usually from your arm or hand. Let them know if you are afraid of needles, get unwell with the sight of blood or are allergic to plasters or latex. 

They put a tight band (tourniquet) around your arm above the area where they take the sample. You may need to clench your fist to make it easier to find a vein.

They clean your skin and then put a small needle into your vein. Next, they attach a small bottle or syringe to the needle to draw out some blood. They might fill several small bottles.

Once they have all the samples, they release the band around your arm. They then take the needle out and put pressure on the area with a cotton wool ball or small piece of gauze for a few minutes. This helps to stop bleeding and bruising.

Look away when they’re taking the blood if you prefer. Tell your doctor, nurse or phlebotomist if you feel unwell.

Getting your results

You usually get your results within a day or so of having the test.

Urine samples

To collect a clean urine sample:

  • you have a small, sterile plastic tube labelled with your name, date of birth, and the date
  • wash your hands thoroughly
  • pass urine into the tube
  • screw the lid of the tube shut
  • wash your hands
  • give the tube to the nurse or send it to your monitoring hospital

You usually get your results within a day or so of having the test.

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