Progesterone

Progesterone: What It Does and How It Changes in Menopause

Progesterone is a hormone that gets the lining of your womb ready for pregnancy each month. It is made mostly in the ovary after an egg is released. In the years before menopause, you release eggs less often, so progesterone levels fall. Progesterone also plays an important part in hormone replacement therapy (HRT).

Please note: This page shares general health information in simple words. It is not medical advice. Every body is different, so talk to a doctor or gynaecologist before you try any treatment.

Key Facts About Progesterone

Progesterone is a hormone made mainly by the ovaries.
It is made after an egg is released each month.
It thickens the lining of the womb so a baby could grow there.
If you do not get pregnant, progesterone drops and your period starts.
In perimenopause, progesterone often falls before estrogen does.
In HRT, a form of progesterone protects the lining of the womb.

What Is Progesterone?

Progesterone is a hormone. A hormone is a chemical messenger that travels in your blood.

Each month, your ovary releases an egg. The small space left behind in the ovary turns into something called the corpus luteum. It makes most of your progesterone.

If you get pregnant, the placenta takes over and makes progesterone. The adrenal glands make a small amount too.

What Does Progesterone Do?

Progesterone gets your body ready for pregnancy. It:

Makes the lining of the womb thick and soft so a fertilised egg can attach
Helps keep a pregnancy going in the early weeks
Helps get the breasts ready for feeding a baby

If you do not get pregnant, your progesterone level drops. The lining of the womb then comes away. This is your period.

How Does Progesterone Change in Perimenopause?

In perimenopause, you release eggs less often, so you make less progesterone. In many months, no egg is released at all. Without an egg, very little progesterone is made.

Estrogen can stay high or even jump up at times in perimenopause. When progesterone is low and estrogen is high, you may notice:

Irregular periods
Heavier periods
Sore breasts
Trouble sleeping
Mood changes

After menopause, both progesterone and estrogen stay low.

What Are the Signs of Low Progesterone?

Signs of low progesterone can include:

Irregular or missed periods
Spotting between periods
Trouble getting pregnant
Trouble sleeping
Feeling anxious or low

These signs can have many causes. Only a doctor can check your hormone levels and find the cause.

Why Is Progesterone Part of HRT?

If you still have a womb, HRT includes a form of progesterone to keep the womb lining safe. Estrogen on its own can make the lining of the womb grow too thick. Over time, this can raise the risk of womb cancer. Adding progesterone stops this from happening.

This type of HRT is called combined HRT. If you have had your womb removed, you can usually take estrogen on its own.

Doctors may use natural progesterone or a man-made version called a progestin. Both are known as progestogens. Read more about hormone replacement therapy.

Can Progesterone Cause Side Effects?

Some women notice side effects when they start HRT with progestogen, such as:

Sore breasts
Headaches
Mood changes
Spotting or bleeding between periods

These are usually mild. They often settle within the first 3 months. If they do not, your doctor may change the type or dose.

When Should You See a Doctor?

See a doctor or gynaecologist if:

Your periods become very heavy or come very close together.
You bleed between periods or after sex.
You have any bleeding after menopause.
You are thinking about HRT.
You are having trouble getting pregnant.

Related Terms

Shop menopause care: Sirona Menopause Collection

Sources

Cleveland Clinic. Progesterone. https://my.clevelandclinic.org/health/body/24562-progesterone
NHS. About hormone replacement therapy (HRT). https://www.nhs.uk/medicines/hormone-replacement-therapy-hrt/about-hormone-replacement-therapy-hrt/
NHS. Benefits and risks of hormone replacement therapy (HRT). https://www.nhs.uk/medicines/hormone-replacement-therapy-hrt/benefits-and-risks-of-hormone-replacement-therapy-hrt/
NHS. Side effects of hormone replacement therapy (HRT). https://www.nhs.uk/medicines/hormone-replacement-therapy-hrt/side-effects-of-hormone-replacement-therapy-hrt/
NICE. Menopause: identification and management (NG23). https://www.nice.org.uk/guidance/ng23

Disclaimer: This page is for general information only. It is not a substitute for advice, diagnosis or treatment from a qualified doctor. It was written by the Sirona Content Team using the trusted medical sources listed above. Always talk to your doctor or gynaecologist about your symptoms and before starting any medicine, supplement or product. If you have heavy bleeding, chest pain, trouble breathing or severe pain, get medical help right away.