Epidemiology: How Common Is Uterine Cancer?

Uterine cancer stands as the most common cancer affecting the female reproductive system in both the United States and Canada. Every year in the United States, approximately 65,000 to 67,880 women receive a uterine cancer diagnosis, making it one of the more frequently encountered cancers among women. This type of cancer accounts for roughly 3.5% of all cancer cases diagnosed in the country.^[1][4][8]

The numbers tell an important story about who faces this health challenge. About 3% of women will be diagnosed with uterine cancer at some point during their lives. While this may seem like a small percentage, it translates to thousands of women each year facing this diagnosis. Understanding these patterns helps healthcare providers and communities prepare better resources for prevention, early detection, and treatment.^[11]

The risk of developing uterine cancer increases significantly with age. Most cases occur in women who are going through or have already completed menopause—the natural time of life when menstrual periods stop permanently. Women over the age of 45 are most frequently affected, though younger women can develop this cancer as well. The condition primarily develops after menopause, which typically happens around the early 50s for most women.^[1][8]

Recent research has revealed a troubling trend: uterine cancer rates are increasing in the United States. More concerning still, death rates from rare and aggressive types of uterine cancer have been rising each year. Studies from 2010 to 2017 showed significant annual increases in deaths from these aggressive forms. This rise has not affected all communities equally—Hispanic, Black, and Asian populations have experienced disproportionately higher increases in uterine cancer deaths compared to other groups.^[23]

Approximately 13,250 people are expected to die from uterine cancer in the United States in 2024. While death rates for the most common type of uterine cancer (called endometrioid cancer) have remained relatively stable, the increases in deaths from rarer, more aggressive types underscore the need for greater awareness and improved access to care across all communities.^[23]

Causes: What Leads to Uterine Cancer?

The exact cause of uterine cancer remains unclear to researchers. What scientists do understand is that something triggers changes in the DNA of cells within the uterus. These genetic changes, called mutations, transform normal, healthy cells into abnormal ones. When cells become abnormal, they may start growing and multiplying without the usual controls that keep our bodies functioning properly. As these cells continue to divide uncontrollably, they can form a mass of tissue called a tumor.^[5][11]

The uterus is a hollow, muscular organ shaped like an upside-down pear. It sits in the pelvis, between the hip bones, and serves as the place where a baby develops during pregnancy. The inner lining of the uterus is called the endometrium, which is made up of tissue containing many glands. Most uterine cancers begin in this endometrial lining, which is why they are often called endometrial cancers.^[1][4]

Before cells in the endometrium become cancerous, they sometimes go through precancerous changes. This means the cells are not normal, but they’re not yet cancer either. There’s a chance these abnormal cells could become cancer if they’re not treated. The precancerous condition of the uterus is called endometrial hyperplasia, which refers to a thickening of the uterine lining. This condition can be detected and treated before it progresses to cancer.^[4]

Hormones play a significant role in the development of uterine cancer. Two hormones in particular—estrogen and progesterone—regulate changes in the endometrium as part of the monthly menstrual cycle. Estrogen causes the endometrial lining to thicken each month in preparation for a possible pregnancy. If pregnancy doesn’t occur, progesterone levels drop, and the lining sheds during menstruation. When the balance between these hormones is disrupted, particularly when estrogen levels increase without corresponding progesterone levels, the risk of endometrial cancer can rise.^[11][23]

Risk Factors: Who Faces Higher Risk?

Several factors and conditions can increase a woman’s chances of developing uterine cancer. Many of these risk factors relate to how hormones, particularly estrogen, affect the body over time. Understanding these factors can help women and their healthcare providers make informed decisions about monitoring and prevention strategies.

Obesity represents one of the most significant risk factors for uterine cancer. Fat cells in the body produce estrogen, which means women carrying excess weight have higher estrogen levels circulating in their bodies. This increased estrogen exposure occurs without the balancing effect of progesterone, creating conditions that favor the development of endometrial cancer. Similarly, metabolic syndrome—a cluster of conditions including high blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol levels—also raises risk.^[6][23]

Type 2 diabetes has been linked to increased uterine cancer risk. This connection may relate to insulin resistance and obesity, which often accompany diabetes, but the relationship is complex and not fully understood. Women with polycystic ovary syndrome (PCOS), a hormonal disorder that causes irregular periods and often leads to obesity, also face elevated risk because their bodies produce excess estrogen without regular ovulation to balance it with progesterone.^[6][8]

Reproductive history influences uterine cancer risk in several ways. Women who started menstruating at an early age or who experienced menopause later than average have longer lifetime exposure to estrogen, which increases risk. Never having been pregnant means never experiencing the extended periods of high progesterone levels that occur during pregnancy, which may offer some protective effect. Starting menstruation early, never giving birth, or starting menopause at an older age all result in more menstrual cycles over a lifetime, and therefore more estrogen exposure.^[6][8]

Certain medical treatments and medications can affect uterine cancer risk. Taking estrogen-only hormone replacement therapy after menopause, without progesterone to balance it, significantly increases risk. The medication tamoxifen, commonly used to prevent or treat breast cancer, can also raise the risk of developing uterine cancer. Women who have received radiation therapy to the pelvis area for other cancers face increased risk as well.^[6][8]

Family history matters when it comes to uterine cancer. Having a mother, sister, or daughter who has had endometrial cancer increases your risk. Certain inherited genetic conditions, particularly Lynch syndrome (also known as hereditary nonpolyposis colorectal cancer), substantially raise the risk of developing uterine and several other types of cancer. Women with a family history of these conditions may benefit from genetic counseling and testing.^[6][8]

Having endometrial hyperplasia, a condition where the uterine lining becomes too thick, represents a precancerous state that can develop into cancer if not treated. Additionally, having had retinoblastoma in childhood—a rare cancer of the eye—has been associated with increased risk of later developing uterine cancer.^[8]

Symptoms: Warning Signs to Watch For

Uterine cancer often announces itself through specific warning signs, particularly abnormal vaginal bleeding. Recognizing these symptoms early and seeking medical attention promptly can make a significant difference in outcomes, as this cancer is often highly treatable when detected in its early stages.

The most common symptom of uterine cancer is abnormal vaginal bleeding. For women who have gone through menopause and no longer have monthly periods, any amount of vaginal bleeding or spotting is considered abnormal and should be evaluated by a doctor. Even a small amount of blood is significant and warrants immediate medical attention. For women who haven’t yet reached menopause, abnormal bleeding might appear as bleeding between regular menstrual periods, periods that are unusually heavy or prolonged, or bleeding that occurs much more frequently than the normal monthly cycle. Women over age 40 who experience extremely prolonged, heavy, or frequent vaginal bleeding should also be evaluated.^[5][8][11]

Many women with uterine cancer experience unusual vaginal discharge that isn’t related to their normal menstrual cycle. This discharge might be thin, white, or clear, and it can occur in women who are postmenopausal. Any unusual discharge should be brought to your doctor’s attention, especially if it persists or is accompanied by other symptoms.^[8]

Pelvic pain or discomfort represents another important warning sign. This might manifest as lower abdominal pain, cramping in the pelvis just below the belly, or a feeling of pressure in the pelvic area. Some women describe a bloated feeling in the abdomen or experience pain in this region that doesn’t go away.^[5][8][11]

Changes in urinary habits can also signal uterine cancer. Some women experience pain or difficulty while urinating, while others find themselves needing to urinate more frequently than usual. These symptoms occur because the growing tumor may press against the bladder or other nearby structures.^[8]

Pain during sexual intercourse is another symptom that women with uterine cancer sometimes report. Additionally, some women may notice a lump or mass in the vaginal area, though this is less common than other symptoms.^[8]

Unexplained weight loss can occasionally accompany uterine cancer, particularly in more advanced cases. While weight loss without trying might seem like a welcome change, when it occurs without known reason and alongside other symptoms, it deserves medical evaluation.^[8]

Prevention: Steps to Reduce Your Risk

While there is no guaranteed way to prevent uterine cancer completely, several lifestyle choices and medical strategies can help lower your risk. Taking proactive steps toward better health may reduce your chances of developing this disease.

Maintaining a healthy weight stands as one of the most important preventive measures you can take. Since obesity significantly increases uterine cancer risk by raising estrogen levels, achieving and maintaining a healthy weight through balanced eating and regular physical activity can help protect you. Even modest weight loss can make a meaningful difference if you’re currently overweight.^[6]

Regular physical activity offers protective benefits beyond weight management. Exercise helps regulate hormone levels, improves insulin sensitivity, and supports overall metabolic health. Aim for at least 150 minutes of moderate-intensity activity each week, such as brisk walking, swimming, or cycling. Physical activity doesn’t have to be strenuous to be beneficial—consistency matters more than intensity for many health benefits.^[6]

If you’re considering hormone replacement therapy after menopause, have an open conversation with your healthcare provider about the risks and benefits. Taking estrogen-only hormone therapy increases uterine cancer risk, but combining estrogen with progesterone helps protect the uterine lining. Your doctor can help you understand whether hormone therapy is appropriate for you and, if so, which combination offers the best balance of benefits and risks for your individual situation.^[6]

For women taking tamoxifen for breast cancer prevention or treatment, be aware that this medication can increase uterine cancer risk. Don’t stop taking tamoxifen without discussing it with your doctor, as the benefits for breast cancer may outweigh the risks. Instead, work with your healthcare team to ensure appropriate monitoring through regular gynecological examinations and promptly reporting any abnormal bleeding.^[6]

Birth control pills (oral contraceptives) may offer some protection against uterine cancer. Studies have shown that women who take oral contraceptives have a lower risk of developing this cancer, and this protective effect can last for years after stopping the pills. However, contraceptives aren’t right for everyone, so discuss this option with your healthcare provider.^[6]

Regular gynecological checkups remain essential for women’s health. During these visits, your healthcare provider can perform pelvic examinations and discuss any symptoms or concerns you may have. While there is no standard screening test for uterine cancer like there is for cervical or breast cancer, annual pelvic examinations are recommended and provide an opportunity for early detection of problems.^[1]

If you have a family history of uterine cancer or inherited conditions like Lynch syndrome, consider genetic counseling. A genetic counselor can help assess your risk, explain testing options, and discuss strategies for early detection and prevention tailored to your individual risk level. Some women at very high risk may benefit from more frequent monitoring or, in certain cases, preventive surgery.^[8]

Pathophysiology: How Uterine Cancer Develops

Understanding how uterine cancer develops in the body helps explain why certain symptoms occur and why specific treatments work. The disease involves multiple changes at the cellular and tissue level that disrupt the normal functioning of the reproductive system.

The endometrium undergoes regular cycles of growth and shedding throughout a woman’s reproductive years. Each month, hormones signal the endometrial lining to thicken in preparation for a potential pregnancy. Estrogen drives this thickening process, causing the glandular cells in the endometrium to multiply and the lining to become plush and rich in blood vessels. If pregnancy doesn’t occur, progesterone levels drop, triggering the breakdown and shedding of this lining during menstruation. This cycle repeats monthly, controlled by the delicate balance between estrogen and progesterone.^[11]

When something disrupts this hormonal balance—particularly when estrogen levels remain elevated without adequate progesterone to counterbalance them—the endometrium may continue to thicken abnormally. This prolonged stimulation can lead to endometrial hyperplasia, where the lining becomes too thick and the cells within it start to show abnormal characteristics. Over time, some of these abnormal cells may acquire additional genetic mutations that allow them to escape normal growth controls entirely.^[4]

At the molecular level, uterine cancer begins when DNA mutations occur in endometrial cells. These mutations affect genes that normally control when cells divide, how long they live, and when they should die. Healthy cells have built-in mechanisms that repair DNA damage or trigger cell death if the damage is too severe to fix. Cancer cells, however, bypass these safety mechanisms. The mutations allow them to ignore signals that would normally tell them to stop dividing or to undergo programmed cell death.^[5]

As mutated cells accumulate and multiply, they form a mass of abnormal tissue—a tumor. In the early stages of endometrial cancer, this tumor remains confined to the endometrial lining. The tumor continues to grow, and its cells may develop additional mutations that make them increasingly abnormal and aggressive. Eventually, cancer cells can invade through the endometrial lining into the deeper muscle layer of the uterus, called the myometrium.^[4]

One characteristic of cancer cells is their ability to invade surrounding tissues and spread to other parts of the body through a process called metastasis. Uterine cancer cells can spread in several ways. They may grow directly into nearby organs such as the cervix, vagina, or ovaries. They can also enter lymphatic vessels and travel to lymph nodes in the pelvis and abdomen. In more advanced cases, cancer cells may enter the bloodstream and spread to distant organs such as the lungs, liver, or bones.^[4]

There are two main types of uterine cancer, each arising from different cell types and behaving somewhat differently. Endometrial carcinoma begins in the glandular cells of the endometrium and accounts for about 95% of all uterine cancer cases. This type is generally more responsive to hormone influences and often has a better prognosis, especially when caught early. Uterine sarcoma, on the other hand, develops in the muscle cells or connective tissue of the uterus. Though much rarer—making up only 5% to 10% of cases—uterine sarcomas tend to be more aggressive and harder to treat than endometrial carcinomas.^[4][8][11]

The symptoms of uterine cancer relate directly to these pathological changes. Abnormal bleeding occurs because the tumor disrupts the normal structure and function of the endometrial lining and its blood vessels. As the tumor grows, it can cause the abnormal tissue to bleed irregularly. Pelvic pain and pressure result from the tumor’s physical size as it grows and potentially presses against other structures in the pelvis. If the cancer spreads to the cervix or invades deeply into the uterine muscle, pain may become more pronounced.^[5]

The progression from normal cells to hyperplasia to cancer doesn’t happen overnight. It typically occurs over months or even years, which is why regular medical checkups and prompt attention to symptoms are so important. This timeline also explains why endometrial cancer, when detected early, is often highly curable—doctors can intervene before the disease has progressed too far or spread beyond the uterus.^[4]