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Progesterone and Autoimmune Diseases

by Dr. Jennifer Bennett

This is Part 2 of our 4-part series in how hormones affect the immune system.

Progesterone is an important hormone in the female body. It is produced in the ovaries after a woman ovulates. Once it is produced, it can do many things. It’s responsible for helping to prepare the uterine lining for pregnancy. It is also responsible for relaxing muscles, increasing blood flow and increasing serotonin production (for mood). It is thought to be the prime hormone for pregnancy. This means that all it’s effects are geared towards helping to cause and maintain pregnancy.

So if we were to think about what progesterone does, we think about how it relates to pregnancy. It helps to relax the nervous system (so that women are not as anxious about having a baby). It helps increase blood flow (why pregnant women are so hot all the time). And it subsequently suppresses the immune system. Because you don’t want the immune system to kick out the seemingly foreign thing growing in the uterus.

It is the effect on the immune system that we will discuss today.

Progesterone’s Effect on the Immune System

Progesterone has a strong effect on the immune system. When progesterone levels are high, the immune system is less likely to flare. When progesterone levels are low, the immune system will flare a lot. It is commonly known that when women with autoimmune diseases get pregnant, they often have a significant reduction in their autoimmune symptoms. This is because of the high levels of progesterone they have during that time.

It is also commonly known that many women do not know that they have an autoimmune disease until after they have a baby. This is when autoimmune diseases commonly flare for most women. After a woman has a baby, her progesterone levels drop. And unless that woman starts her period soon after birth, her levels may stay low for a long time. Especially if that woman is breastfeeding, which can prevent periods from happening.

Women who also have irregular cycles will also commonly have flares in autoimmune diseases more regularly. Short cycles, inconsistent cycle lengths, heavy bleeding and significant menstrual cramping can all be signs of low levels of progesterone in women. Also, women who have gone into menopause have no progesterone as they are no longer ovulating any more. This is one of the reasons we see an increase in conditions like rheumatoid arthritis. If women are on hormone replacement therapy without progesterone, they are way more likely to develop autoimmune diseases.

How to Treat Progesterone Levels

If you think that your progesterone levels may be low, there are a number of ways to test it. The most common way is a blood test. This may be helpful if you are testing blood levels in the luteal phase (the time between ovulation and when you start your period). If your cycles are irregular, or you test too close to your period, you may not get an accurate reading. This is why having a trained physician in this area to help you assess this is important.

Other ways to tell if you have low progesterone would be to do a basal body temperature. This involves taking your temperature every morning, before you get out of bed. You can chart the temperatures over time, and the data that you get will tell you what your hormones are doing on a daily basis. When progesterone levels are high in the luteal phase, your temperatures should rise and be at least 0.5 degrees higher than they are right after your period. If they don’t rise or stay elevated before your period, or if they are fluctuating up and down a lot, then this might mean you have low levels of progesterone.

If your progesterone levels are low, there are a number of ways to help treat this. For pre-menopausal women that are still menstruating, herbs like Vitex agnus-castus can help your body make its own progesterone. If you need to build both cortisol and progesterone, then you may want to consider some hormone precursors like pregnenolone.

What Can You Do to Get Help?

Postmenopausal women should always be on progesterone if they are on estrogen replacement therapy, especially if they still have a uterus. Estrogen without progesterone will increase the rate of uterine cancer in women on HRT. It can also be given to some women if their bodies are having a harder time making their own progesterone. This should be done under the guidance of an experienced practitioner.

In any rate, you should always work with a provider that is well versed in understanding the effects of progesterone on the immune system. If you have questions about therapies that our providers use, or if you are wondering progesterone or pregnancy is impacting your autoimmune disease, you can contact our office to schedule a free phone consult with one of physicians today.

Looking for more information on autoimmune diseases? Get our FREE ebook The 5 Foundations of Autoimmune Diseases, register for one of our FREE online webinars, or check out our blog for additional articles.

Want More Information?

Get our FREE ebook The 5 Foundations of Autoimmune Diseases, register for one of our FREE online webinars, or check out our blog for additional articles.

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