What to Know About Progesterone and Why It Matters for Your Health

What is progesterone, and why does it matter for your body? It’s one of your primary sex hormones, working hand-in-hand with estrogen to regulate your period, balance your mood, and prep your body for a possible pregnancy. 

When progesterone dips too low, you might experience irregular periods, mood swings, and trouble conceiving. 

In this guide, we’ll walk you through what progesterone does at every stage of life, how to spot signs of an imbalance, and which treatments can help you get back to feeling like yourself again.

Progesterone plays a key role in reproductive and hormonal health. Here’s how:

• It prepares the uterus for pregnancy. After ovulation, progesterone helps thicken the lining of the uterus, making it easier for a fertilized egg to attach and grow.

• It supports early pregnancy. Progesterone helps maintain the uterine lining, which is essential for a healthy pregnancy.

• It influences brain and mood health. Progesterone can have a calming effect by interacting with GABA receptors in your brain. This might translate to better sleep and lower anxiety, especially during the second half of your menstrual cycle.

• It balances other hormones. Progesterone helps keep estrogen levels in check. This is important for preventing symptoms like heavy periods or mood swings.

Progesterone vs. Estrogen

Estrogen and progesterone are both crucial for your reproductive health, but they play different roles.

Estrogen helps build up the uterine lining before ovulation and shapes traits like breasts, hips, and how your body stores fat. 

After ovulation, progesterone enters the picture. It prepares your body for pregnancy. If pregnancy doesn’t happen, progesterone levels drop, which brings on your period.

Think of it this way: estrogen builds the uterine lining in the first half of your cycle, and progesterone keeps it stable in the second half. 

Progesterone During Pregnancy

Early in pregnancy, your body makes more progesterone to support the embryo, keep the uterine lining healthy, and prevent contractions. Later, it helps prepare your breasts for breastfeeding and keeps the uterus relaxed until it’s time for labor.

Progesterone During Menopause

As you enter perimenopause and approach menopause, progesterone levels drop — often faster than estrogen. 

This hormonal shift can cause symptoms like:

• Irregular cycles

• Heavier bleeding

• Anxiety

• Trouble sleeping

Your ovaries produce most of your body’s progesterone — specifically the corpus luteum, a temporary organ that forms after ovulation. Its main job? Getting the uterus ready for a possible pregnancy. 

If there’s no pregnancy, the corpus luteum breaks down, progesterone drops, and your period starts.

Your body also makes smaller amounts of progesterone in other places:

• Adrenal glands

• Placenta (during pregnancy)

• Fat tissue

There’s no set “normal” range for progesterone. Levels naturally rise and fall throughout your menstrual cycle. After you ovulate, progesterone peaks, then drops again if pregnancy doesn’t happen. So, when you measure matters.

If your healthcare provider wants to check your progesterone, they’ll likely order a simple progesterone blood test, sometimes called a PGSN test. This helps spot low levels, and also reveals when you’re actually ovulating. 

If you’re not pregnant, low progesterone can cause symptoms like:

• Irregular or missed periods

• Trouble getting or staying pregnant

• Mood changes, including anxiety or depression

• Trouble sleeping or insomnia

• Hot flashes

Low progesterone during pregnancy can lead to:

• Ectopic pregnancy

• Miscarriage

• Preterm labor

What Conditions Affect Progesterone Levels?

Progesterone levels can shift due to health conditions and lifestyle habits. Knowing what can throw your hormones off balance can help you and your healthcare provider find the right treatment approach.

Here are some common causes of unbalanced progesterone levels.

• Perimenopause. As you approach menopause, progesterone levels start to fluctuate, declining over time, causing irregular periods, mood swings, and sleep issues.

• Menopause. After menopause, your body makes very little progesterone, leading to hot flashes, vaginal dryness, and changes in mood or sex drive.

• Polycystic Ovary Syndrome (PCOS). PCOS disrupts ovulation and lowers progesterone, which can cause acne, weight gain, and thickening of the uterine lining.

• Stress. Chronic stress raises cortisol, which can interfere with ovulation and lower progesterone levels, worsening anxiety and sleep problems.

• Hypothyroidism. An underactive thyroid can lower progesterone, leading to fatigue, irregular periods, and fertility problems.

• Low cholesterol. Cholesterol is a building block for hormones. Very low cholesterol (often from extreme dieting) can mean less progesterone, affecting periods and fertility.

• Obesity. Extra body fat can increase estrogen, throwing off hormone balance and causing an irregular cycle.

• Over-exercising and dieting. Too much exercise or too little food can stop ovulation, lowering progesterone and leading to missed periods, low energy, and fertility challenges.

• Endometrial hyperplasia. High estrogen and low progesterone can make the uterine lining too thick, causing heavy bleeding and raising the risk of endometrial cancer. 

• Some medications. Drugs like corticosteroids or seizure meds can also affect hormone levels.

If any of these sound familiar, know that support is available. Talk to your healthcare provider about your symptoms. With the right support, you can get your hormones back in balance.

There are many safe, effective ways to support healthy progesterone levels. Here’s a breakdown of your options:

Progesterone 

If your body isn’t making enough progesterone, getting it in other ways can help restore balance. Here’s what your healthcare provider might suggest:

• Hormonal IUD. This device releases a small amount of progestin (a synthetic form of progesterone) into the uterus. It can help regulate bleeding and provide birth control. 

• Progestin-only pills (the “minipill”). This birth control pill is a good option for those who can’t take estrogen or are in perimenopause.

• Progesterone creams, gels, or suppositories. You apply creams or gels to the skin to boost progesterone levels. Suppositories go inside the vagina. Your provider might suggest them to prevent preterm birth if you have a short cervix.

When choosing a treatment, it’s helpful to know the difference between bioidentical progesterone (identical to what your body makes) and synthetic progestins (lab-make, but works similarly).

Your provider can walk you through the pros and cons of each option and help you decide what’s best for your body.

Hormone Replacement Therapy (HRT)

HRT is one of the most effective ways to manage moderate to severe menopause symptoms. It typically combines estrogen with progesterone or progestin — unless you’ve had a hysterectomy, in which case, your provider might recommend estrogen-only HRT. 

HRT can help:

• Reduce hot flashes, night sweats, mood swings, and vaginal dryness

• Protect the uterine lining from estrogen-related changes

• Support bone health and possibly lower your risk of heart disease and dementia (when started before age 60 or within 10 years of menopause)

HRT comes in several forms, so ask your healthcare provider which might be right for you.

Lifestyle and Nutritional Support

Hormone therapy isn’t the only option. Healthy habits can also support your body’s natural hormone production.

Key nutrients like zinc and magnesium play a key role in progesterone synthesis.

Try incorporating more whole foods into your diet, like:

• Leafy greens

• Nuts and seeds

• Whole grains (like farro, oats, and barley)

• Legumes (like chickpeas, black beans, tempeh, and tofu)

Eating well, managing stress, getting enough sleep, and maintaining a healthy weight can all help keep your hormones balanced during perimenopause and menopause.

Progesterone plays a vital role in reproductive health. Levels naturally fluctuate with your cycle and across life stages like perimenopause and menopause.

Here’s what to remember:

• The ovaries make most of your body’s progesterone. 

• Low progesterone can cause irregular periods, sleep issues, mood changes, and fertility challenges.

• Treatment options for low progesterone include prescription progesterone, hormone replacement therapy, and lifestyle changes.

If you’re noticing symptoms of low progesterone or managing a condition that influences your hormone levels, you’re not alone — and treatment is available. Talk to a healthcare provider about your options.