Molar pregnancy

Also called Hydatidiform mole or Gestational trophoblastic disease

A molar pregnancy is when a fertilised egg develops abnormally and grows into a mass of cells instead of a healthy pregnancy. It is rare and is caused by a problem with the genetic material at fertilisation. It cannot continue as a normal pregnancy. It is often found on an early scan or after unusual bleeding.

Last updated Nov 9, 2026

What it is

The tissue is removed with a small procedure. Regular blood or urine tests for pregnancy hormone (hCG) are then done until levels return to normal.

Rarely, abnormal cells remain and need treatment, which is very effective.

Common signs

  • Bleeding from the vagina in early pregnancy
  • Severe sickness
  • A swollen tummy larger than expected
  • Often found on a scan

How it is usually diagnosed

  • Ultrasound scan
  • hCG blood tests
  • Examination of the tissue after removal

Records worth keeping

Keeping these together makes each appointment easier, especially when you see a new doctor:

  • Ultrasound and histology reports
  • hCG results until normal
  • Specialist follow-up letters

Questions to ask your doctor

  • How long will I need hCG checks?
  • When is it safe to try for another pregnancy?
  • What is the chance it happens again?

When to get help right away

Call 112 or go to the nearest emergency department if you have:

  • Heavy bleeding, severe pain or feeling faint: call 112

This page is general information. It is not a diagnosis and does not replace a doctor who knows your history. Medfold keeps your records organised; it does not interpret them.

Sources