Several medical conditions can increase the risk of endometrial cancer. Understanding these health factors can give you a clearer picture of your own risk.

This article covers eight conditions related to endometrial cancer. For personalized guidance on how your health may influence your cancer risk, consider speaking with your gynecologist (a doctor who diagnoses and treats diseases of the female reproductive system).

What Causes Endometrial Cancer?

Endometrial cancer occurs when cells in the endometrium (the lining of the uterus) begin to grow out of control. Researchers don’t know the exact cause of endometrial cancer. However, the condition is linked to certain genetic changes and an imbalance of the hormones estrogen and progesterone. Having high levels of estrogen for a long time is associated with a higher risk of endometrial cancer.

Conditions linked to endometrial cancer may be related to genetic changes or health conditions that can affect the balance of hormones in your body.

1. Obesity

Having a higher body weight or obesity appears to increase the risk of endometrial cancer. The medical term “obesity” refers to a body mass index (BMI) of 30 or greater. According to the American Cancer Society, women who have a BMI of 25 to 29.9 are about twice as likely to develop endometrial cancer compared to those with a lower BMI, and those with a BMI of at least 30 are about three times more likely to be diagnosed with the condition.

Researchers estimate that between 26 percent and 47 percent of all cases of endometrial cancer are linked to overweight and obesity, according to the National Cancer Institute. One reason for the higher risk may be that having more fat tissue can increase estrogen levels. Ovaries make most of the body’s estrogen. However, fat tissue can also change androgen hormones into estrogen, raising estrogen levels.

Additionally, obesity increases your risk of other conditions associated with endometrial cancer, such as metabolic syndrome and diabetes.

2. Metabolic Syndrome and Diabetes

Metabolic syndrome is a group of co-occurring conditions that raise the risk of heart disease, stroke, and diabetes. Conditions associated with metabolic syndrome include:

• Excess fat in your abdomen (stomach area)
• High blood pressure
• High blood sugar levels
• High blood triglyceride levels
• Low levels of high-density lipoprotein (HDL, also known as good cholesterol)

Researchers have found that each condition linked with metabolic syndrome (except low HDL) is associated with an increased risk of endometrial cancer.

Metabolic syndrome also makes you more likely to develop type 2 diabetes, a condition that causes high blood sugar levels. A 2019 study in the journal BMC Cancer reported that women with type 2 diabetes had a 72 percent higher risk of developing endometrial cancer than women without type 2 diabetes.

3. Breast and Ovarian Cancer

Having a history of breast cancer or ovarian cancer may also increase the likelihood of being diagnosed with endometrial cancer. Factors that contribute to this higher risk include shared risk factors, cancer-related factors, certain treatment for breast cancer and, rarely, ovarian cancer.

Shared Risk Factors

Endometrial, breast, and ovarian cancers share some similar risk factors, including:

• Having obesity
• Being of an older age
• Starting menstruation (period) at an early age
• Beginning menopause at a later age
• Giving birth for the first time at a later age or having never been pregnant

Ovarian Tumor

A specific type of ovarian cancer called a granulosa cell tumor often produces estrogen. High levels of this hormone may raise the risk of endometrial cancer.

Hormone Therapy for Breast or Ovarian Cancer

Tamoxifen is a treatment option often used in breast cancer and, occasionally, some types of ovarian cancer. This medication blocks the effect of estrogen in some tissues but can act like this hormone in the uterus. Tamoxifen may cause the lining of the uterus to grow even after menopause.

Although taking tamoxifen increases the likelihood of developing endometrial cancer, the risk is still low — less than 1 percent risk a year. If you’re taking tamoxifen, it’s important to follow up with your health care provider right away if you notice symptoms of endometrial cancer, such as vaginal bleeding.

4. Endometriosis

Endometriosis is a condition in which tissue similar to the endometrium grows outside the uterus. Researchers have found that having endometriosis may increase the risks of endometrial and breast cancer. People who have endometrial cancer may not know they have endometriosis until they go through the process of diagnosing cancer.

5. Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) occurs when the ovaries make excess androgen hormones, creating a hormonal imbalance. In a study published in the journal Human Reproduction, researchers found that women with PCOS were about three times more likely to develop endometrial cancer compared to those without PCOS.

Additionally, PCOS is linked with conditions that increase the risk of endometrial cancer, such as obesity and type 2 diabetes.

6. Endometrial Hyperplasia

With endometrial hyperplasia, the endometrium becomes too thick, which sometimes leads to endometrial cancer.

Endometrial hyperplasia can occur when estrogen levels remain high for a long time without enough progesterone to balance them. Reproductive factors, such as starting your period at an early age, entering late menopause, or never being pregnant, can raise estrogen exposure.

Taking tamoxifen or using postmenopausal hormone therapy with estrogen alone can also cause endometrial hyperplasia.

Not all cases of endometrial hyperplasia lead to cancer. Endometrial hyperplasia without atypia (abnormal cells) may go away on its own. However, in endometrial hyperplasia with atypia — also called endometrial intraepithelial neoplasia — the abnormal cells have a high risk of eventually becoming endometrial cancer. Treating endometrial hyperplasia may help prevent endometrial cancer.

7. Gallbladder Disease

Surgery to treat gallstones — hard pieces of digestive fluid in the gallbladder — may increase the risk of endometrial cancer. A 2022 study in the journal Cancers found that participants who had gallbladder removal to treat gallstones had a higher risk of endometrial cancer for up to 30 years after the surgery. Gallbladder removal was also linked to an increased risk of breast and ovarian cancer.

It’s not clear why these conditions may be associated, but some risk factors for endometrial cancer risk factors overlap with those for gallstones, such as obesity and estrogen exposure.

8. Family Cancer Syndromes

A family cancer syndrome is a genetic mutation (change) passed down through families that increases the risk of certain cancers. Endometrial cancer is associated with two family cancer syndromes — Lynch syndrome and Cowden syndrome.

Lynch Syndrome

Lynch syndrome, also known as hereditary nonpolyposis colon cancer, is caused by certain genetic mutations that make it more difficult for your body to repair damaged DNA (genetic material) or regulate cell growth. These genetic mutations increase the risk of certain cancers, especially colorectal and endometrial cancer. People with Lynch syndrome may have a family history of other cancers, such as:

• Colorectal cancer
• Endometrial cancer
• Ovarian cancer
• Stomach cancer
• Pancreatic cancer
• Small intestine cancer
• Gallbladder cancer
• Kidney cancer
• Bladder cancer
• Brain cancer
• Skin cancer

Women who have Lynch syndrome have about a 70 percent lifetime risk of developing endometrial cancer, according to the American Cancer Society. For women in the general population, the risk is only about 3 percent.

Cowden Syndrome

Cowden syndrome, which is associated with noncancerous growths, is caused by genetic mutations that cause cells to grow uncontrollably. People with Cowden syndrome may also be more likely to develop certain cancers, including:

• Breast cancer
• Endometrial cancer
• Colorectal cancer
• Kidney cancer
• Thyroid cancer
• Melanoma (a type of skin cancer)

Studies have found that the lifetime risk of endometrial cancer in people with Cowden syndrome is 13 percent to 28 percent.

Find Your Team

On MyEndometrialCancerTeam, the social network for people living with endometrial cancer and their loved ones, members come together to ask questions, give advice, and share their stories with others who understand life with endometrial cancer.

Do you have any conditions related to endometrial cancer? Share your thoughts in the comments below, or start a conversation on your Activities page.