Risks for gestational trophoblastic disease

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Some things can affect your risk, or chance, of developing cancer. Certain behaviours, substances or conditions can increase or decrease the risk. Most cancers are the result of many risks. But sometimes cancer develops in people who don't have any risks.

Gestational trophoblastic disease (GTD) rates are higher in certain countries and ethnic groups. Parts of Asia, South America and Africa have higher rates of GTD than Canada, the United States and Europe. In Canada, Inuit have higher rates of GTD compared to other ethnic groups.

Women 40 years of age and older who have been pregnant have a high risk of GTD. Women younger than 20 who have been pregnant are also at an increased risk of GTD.

A previous hydatidiform mole (also called a molar pregnancy) is the main risk for a cancerous (malignant) type of gestational trophoblastic disease (GTD). This risk can’t be changed. Until we learn more about hydatidiform moles, there are no specific ways you can lower your risk for gestational trophoblastic disease.

Previous hydatidiform mole

A hydatidiform mole is a tumour that starts in the layer of the uterus (womb) that normally develops into the placenta during pregnancy. It’s the most common type of non-cancerous (benign) GTD. Women who have had a hydatidiform mole have a higher risk of developing a second one. Your risk increases if you have had 2 or more hydatidiform moles.

Women who have had a hydatidiform mole also have a higher risk of developing a cancerous type of GTD, called gestational choriocarcinoma.

Possible risk factors

Having type A or AB blood has been linked with an increased risk of GTD, but more research is needed to know for sure that this is a risk.

Understanding your cancer risk

To make the decisions that are right for you, ask your doctor questions about risks. Learn how cancer can be prevented and what you can do to reduce your risk.

Expert review and references

  • Canadian Cancer Society | Société canadienne du cancer
  • Diver E, Richardson M, Liao CI, et al.. Age and racial differences in the presentation of gestational trophoblastic neoplasia. International Journal of Gynecological Cancer. 2021: 31(2)194—202.
  • Finch L, Hosterman T, Huang M. A comprehensive assessment of differences in gestational trophoblastic neoplasia (GTN) by race and ethncity: A national program of cancer (NPCR) and surveillance, epidemiology, and end Results (SEER) database study (2117). Gynecologic Oncology. 2023: 176(1)207—208.
  • Horowitz NS, Eskander RN, Adelman MR, Burke W. Epidemiology, diagnosis, and treatment of gestational trophoblastic disease: A Society of Gynecologic Oncology evidenced-based review and recommendation. Gynecologic Oncology. 2021: 163(3)605—613.
  • Joyce CM, Fitzgerald B, McCarthy TV, Coulter J, O'Donoghue K. Advances in the diagnosis and early management of gestational trophoblastic disease. BMJ Medicine. 2022: 1(1)1—16.
  • PDQ Adult Treatment Editorial Board. Gestational Trophoblastic Disease Treatment (PDQ®) – Health Professional Version . Bethesda, MD: National Cancer Institute; 2024. https://www.cancer.gov/.
  • Ross S. Berkowitz, Kevin M. Elias, and Neil S. Horowitz DeVita, Jr Vincent T; Rosenberg, Steven A; Lawrence, Theodore S.. Gestational Trophoblastic Neoplasia. DeVita VT Jr, Lawrence TS, Rosenberg SA. DeVita, Hellman, and Rosenberg's Cancer: Principles & Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 75: 1069-1074.
  • Sun, YS, Paiva G, Braga A. Epidemiology, Genetics, and Pathology in Gestational Trophoblastic Disease. Chi DS, Dizon DS, Berchuck A, Yashar C, eds.. Principles and Practice of Gynecologic Oncology. 8th ed. Philadelphia, PA: Wolters Kluwer; 2025: Kindle version, [chapter 7.1], https://read.amazon.ca/?asin=B0BG3DPT4Q&language=en-CA.

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