Ovary Function Explained: What Your Ovaries Do and Why It Matters

Ovary function is central to reproductive health, hormone balance, and overall wellbeing. These small but mighty organs do far more than most people realize: producing eggs, creating hormones, and influencing everything from bone health to brain function.

Let’s break down what your ovaries do, where they’re located, and why understanding them matters.

What Are the Ovaries?

Your ovaries are small, oval-shaped glands that form a crucial part of the female reproductive system. Each ovary is roughly the size of an almond — about 4 centimeters long — and you have one on each side of your uterus.

Despite their small size, ovaries pack an outsized punch when it comes to your health. They’re part of both your reproductive system and your endocrine (hormone) system, which means their influence extends throughout your entire body.

Where Are the Ovaries Located?

Your ovaries sit in your lower abdomen, one on the right side and one on the left side of your uterus. They’re held in place by several ligaments and muscles:

• The ovarian ligament connects each ovary to your uterus
• The suspensory ligament (also called the infundibulopelvic ligament) connects your ovaries to your pelvic wall and carries the ovarian artery, vein, nerve plexus, and lymphatic vessels
• The broad ligament provides additional support and contains the ovarian ligament, round ligament of the uterus, and IP ligament; the subdivision of it that attaches the ovary is the mesovarium and it encloses the ovary neurovascular supply

Your ovaries don’t actually touch your uterus. They’re positioned near your fallopian tubes, which extend from your uterus with finger-like projections called fimbriae that sweep released eggs into the tubes.

It’s worth noting that your ovaries are located close to other organs, like your bladder, intestines, and ureters (tubes that carry urine from your kidneys). This proximity explains why ovarian cancer symptoms often include bloating, digestive changes, and urinary issues.

The Two Main Functions of Ovaries

The function of ovaries breaks down into two essential jobs: egg production and hormone creation.

1. Producing and Releasing Eggs

Here’s something remarkable: you’re born with all the eggs you’ll ever have. A female baby develops with approximately 1 to 2 million eggs already in her ovaries. By puberty, that number drops to around 300,000 through a natural process of cell death.

During your reproductive years, only about 400 eggs will actually go through ovulation—the process of being released from your ovary.

How ovulation works:

Each month during your menstrual cycle, several eggs begin to mature inside fluid-filled sacs called follicles. Usually, only one follicle becomes dominant and releases its egg around day 14 of your cycle. The released egg travels through the fallopian tube toward your uterus, where it may meet sperm and become fertilized.

If fertilization doesn’t occur, the egg dissolves, and you get your period about two weeks later.

This monthly cycle continues from puberty through menopause, typically from your early teens until around age 51.

2. Creating Essential Hormones

What is the function of ovaries beyond egg production? They’re your body’s primary source of female sex hormones.

Your ovaries produce three key hormones:

Estrogen is the star player. It does far more than support reproduction. Estrogen helps:

• Regulate your menstrual cycle
• Develop secondary sex characteristics during puberty (breasts, body shape, body hair patterns)
• Maintain bone density
• Support cardiovascular health
• Keep your skin elastic and healthy
• Regulate cholesterol levels
• Support brain function and mood
• Keep vaginal tissue healthy and lubricated

Progesterone rises in the second half of your menstrual cycle. It prepares your uterine lining for potential pregnancy by thickening it so a fertilized egg can implant. If pregnancy occurs, progesterone levels stay high to support the developing baby. If not, progesterone drops and triggers your period.

Testosterone (yes, really) is also produced in small amounts by your ovaries. While we think of testosterone as a male hormone, women need it too: for sex drive, bone strength, and muscle mass.

How Ovaries Change Throughout Your Life

Your ovaries aren’t static organs. They evolve dramatically from birth through your senior years. The size, activity level, and hormone production of your ovaries shift in response to age and life stage.

During Reproductive Years

From puberty to menopause, your ovaries are in their prime working years. They’re at their largest size — around 6 centimeters, similar to a kiwi fruit — and produce regular hormone cycles.

Your ovaries typically take turns releasing eggs each month, though it’s not a strict alternating pattern. Sometimes the same ovary releases eggs for several months in a row.

After Menopause

Menopause occurs when your ovaries stop releasing eggs and dramatically reduce hormone production. The average age is 51, but it can happen earlier or later.

Post-menopause, your ovaries shrink considerably, down to about 2 centimeters, roughly the size of a kidney bean. According to research, ovarian volume declines with each decade after age 30, with the most dramatic changes occurring after menopause.

The drop in estrogen and progesterone production can cause:

• Hot flashes and night sweats
• Mood changes
• Sleep disruptions
• Vaginal dryness
• Decreased bone density
• Changes in cholesterol levels

Many women use hormone replacement therapy (HRT) to manage these symptoms.

What’s Inside an Ovary?

The microanatomy of your ovaries reveals three distinct layers:

• The outer epithelium (germinal epithelium): a protective coating of simple cuboidal cells; under the germinal epithelium is a layer of connective tissue called the tunica albuginea, then the cortex, then the medulla
• The cortex: the middle layer containing all those follicles with developing eggs, made of connective tissue
• The medulla: the innermost core containing blood vessels, lymphatic vessels, and nerves

This structure explains why ovarian issues can affect your entire body. The rich blood supply means hormones can quickly enter your bloodstream, and the dense nerve connections explain why ovarian problems often cause pain.

Common Conditions Affecting Ovary Function

Several conditions can disrupt how your ovaries work, affecting everything from your menstrual cycle to your ability to conceive. Some are temporary and resolve on their own, while others require ongoing management or treatment.

Ovarian Cysts

These fluid-filled sacs develop on or in your ovaries. Most are functional cysts. They form naturally during your menstrual cycle when a follicle doesn’t release its egg properly or when the empty follicle doesn’t dissolve as it should.

Functional cysts usually resolve on their own within two to three menstrual cycles. But some cysts grow large, cause pain, or rarely become cancerous. Learn more about what causes ovarian cysts.

Polycystic Ovary Syndrome (PCOS)

PCOS affects about 1 in 8 women globally, though experts believe the actual number is much higher since many women don’t get diagnosed until they try to conceive. In PCOS, follicles develop but fail to release eggs, creating multiple small cysts around the ovary’s outer edge.

Symptoms include irregular periods, acne, excess hair growth, and difficulty conceiving. PCOS is also associated with insulin resistance and increased risk of type 2 diabetes and uterine cancer.

Endometriosis

When tissue similar to your uterine lining grows outside your uterus, including on your ovaries, it’s called endometriosis. This can cause painful cysts called endometriomas. Understanding the connection between endometriosis and ovarian cancer is important for long-term health monitoring.

Primary Ovarian Insufficiency

Formerly called premature ovarian failure, this condition occurs when your ovaries stop functioning normally before age 40. It can result from genetic disorders, autoimmune diseases, or exposure to toxins like chemotherapy, radiation, or cigarette smoke.

Ovarian Cancer

Ovarian cancer develops when cells in the ovaries grow abnormally and uncontrollably. It ranks fifth in cancer deaths among women and causes more deaths than any other cancer of the female reproductive system.

The challenge with ovarian cancer is that symptoms often don’t appear until the disease has progressed. When they do occur, symptoms can include:

• Persistent bloating
• Abdominal or pelvic pain
• Difficulty eating or feeling full quickly
• Urinary urgency or frequency
• Unexplained weight loss or gain
• Fatigue
• Changes in bowel habits

Because these symptoms are easy to dismiss as digestive issues or stress, many cases aren’t detected early. There’s currently no reliable screening test for the general population, which makes awareness of symptoms crucial.

Different types of ovarian cancer behave differently. Borderline ovarian cancer and low-grade serous ovarian cancer are rarer subtypes that primarily affect younger women and require specialized treatment approaches.

Protecting Your Ovarian Health

While there’s no guaranteed way to prevent all ovarian problems, you can support your ovarian health:

• Don’t smoke. Cigarette smoke damages eggs’ genetic material and causes them to die off faster, potentially bringing on earlier menopause and reducing fertility.
• Maintain a healthy weight. This helps regulate hormones and menstrual cycles, and can ease PCOS symptoms.
• Get annual pelvic exams. Regular checkups help catch issues like cysts and tumors that often don’t cause symptoms initially.
• Know your family history. Genetic factors play a role in ovarian cancer risk, especially mutations in BRCA genes.
• Listen to your body. If something feels off, whether it’s pain, irregular bleeding, or persistent bloating, trust your instincts and see your doctor.

The Bottom Line

Ovaries function as more than egg storage facilities. They’re hormone powerhouses that influence your entire body: from your bones to your brain, from your cardiovascular system to your skin.

Understanding what your ovaries do and how they change throughout your life helps you recognize when something’s wrong. Because ovarian problems often cause vague symptoms that overlap with other conditions, knowing what’s normal for your body is your best tool for early detection.

If you’re experiencing concerning symptoms, don’t wait. Consult a healthcare provider — preferably a gynecologic oncologist if ovarian cancer is suspected. Early evaluation can make all the difference.