Granulosa Cells

What are granulosa cells?

Granulosa cells are a type of cell in your ovaries that produce hormones including estrogen and progesterone. Hormones released from the base of your brain (anterior pituitary) control the numbers and function of granulosa cells.

What do granulosa cells do?

Granulosa cells play a key role in the female reproductive system. They help you get and stay pregnant. Granulosa cells produce reproductive hormones and support ovarian follicles. These follicles are small sacs of fluid in your ovaries that contain eggs. Here’s the process:

1. From the first day of your period (menstruation) to the release of an egg (ovulation), your anterior pituitary releases follicle-stimulating hormone (FSH). FSH stimulates the granulosa cells to change androgen sex hormones, released by theca cells, to estrogen sex hormones.
2. As your follicles grow, granulosa cells continue to produce more estrogen. This results in a surge in luteinizing hormone (LH) from your anterior pituitary. The LH surge leads to the release of an egg from your dominant follicle.
3. After ovulation, the follicle collapses and becomes a structure called the corpus luteum. The granulosa cells inside the corpus luteum (granulosa lutein cells) produce the hormone progesterone. This helps to maintain a possible pregnancy.

Granulosa cells also produce other hormones and chemicals including anti-Müllerian hormone (AMH). Since levels of AMH decrease as follicle numbers decrease, AMH testing may help measure egg count. Low levels of AMH in your blood may mean that you have fewer remaining eggs (diminished ovarian reserve).

Where are granulosa cells located?

You can find granulosa cells inside a person’s ovarian follicles. Besides granulosa cells, these follicles contain:

• Immature egg (oocyte).
• Theca cells. These cells respond to LH by producing androgens and progesterone.

What are the types of granulosa cells?

There are two types of granulosa cells:

• Cumulus cells (CC): These cells surround the oocyte and give it nutrients. During ovulation, cumulus cells stay with the egg when it travels through the fallopian tube.
• Mural granulosa cells (MGC): These cells line the walls of the follicles and surround the part of the follicle filled with fluid (antrum). Mural granulosa cells support the follicles’ growth.

What conditions affect granulosa cells?

Conditions that affect granulosa cells include:

• Granulosa cell tumors: This rare type of ovarian cancer makes up 2% of all ovarian tumors. It often occurs around ages 50 to 55. Granulosa cell tumors (or granulosa theca cell tumors) tend to grow slowly and have high recovery rates. Healthcare providers usually use surgery to treat these tumors.
• Juvenile granulosa cell tumors: This type of tumor occurs in 5% of children. Providers can often successfully treat these tumors with surgery in their early stages.

What conditions are related to granulosa cells?

Conditions that may relate to granulosa cells include:

• Infertility: Providers use AMH levels when deciding how much medication they should use to stimulate egg production during treatments for infertility, such as IVF. But low AMH levels don’t give information about the quality of the remaining eggs.
• Polycystic ovarian syndrome (PCOS): Providers don’t know the exact cause of PCOS. But studies suggest that problems with granulosa cells may affect follicle growth and ovulation.
• Primary ovarian insufficiency (POI): Increasing levels of FSH and decreasing quality of granulosa cells may lead to a decrease in the number of a woman’s eggs. POI can impact your ability to get pregnant.

What are common tests to check the health of granulosa cells?

Common tests to check the health of granulosa cells include:

• Blood tests: Granulosa cell tumors often produce chemicals or hormones that providers can measure in your blood. These include inhibin, AMH, estradiol, testosterone and high levels of CA-125.
• CT scan: A CT scan uses X-rays and a computer to produce a 3D image of any tumors. A CT scan usually shows larger tumors better than smaller ones.
• Laparoscopy: During laparoscopy, your provider passes a thin tube through a small incision in your abdomen. They can look at your ovaries and take a sample of cells (biopsy) if needed.
• Pelvic ultrasound: A pelvic ultrasound uses sound waves to look for growths on your ovaries.
• PET scan: A PET scan uses an injectable chemical and a PET scanner to produce images of your ovaries.

What are simple lifestyle changes to keep granulosa cells healthy?

People who’ve had children or use birth control pills have a lower risk of developing ovarian cancer. If ovarian cancer runs in your family, talk to your healthcare provider about your options.

You can also lower your risk of granulosa cell tumors and ovarian cancer by maintaining a healthy lifestyle, including:

• Eating a balanced diet.
• Exercising regularly.
• Limiting your alcohol intake.
• Maintaining a healthy weight.
• Visiting your doctor for annual checkups.

A note from Cleveland Clinic

Granulosa cells are inside your ovaries. These cells produce estrogen, progesterone and other hormones. The hormones play a large part in the female reproductive system, from menstruation to ovulation to egg implantation. Conditions related to granulosa cells include granulosa cell tumors and juvenile granulosa cell tumors. PCOS, POI and female infertility may also relate to granulosa cells. You can reduce your risk of granulosa cell disorders by living a healthy lifestyle and making regular visits to your healthcare provider.