What are the side effects of too much progesterone?

February 13, 2020

What are the side effects of too much progesterone?

What are the side effects of too much progesterone?

Progesterone is a steroid hormone responsible for regulating the menstrual cycle and fertility. It's natural for the body to have more or less progesterone as a woman moves through her monthly period. Progesterone prepares the woman for conception and helps sustain a healthy pregnancy.


Since levels can become high during the monthly cycle and pregnancy, there are no severe side effects. Yet, if levels become imbalanced due to other factors, it can cause health concerns. This article explores the world of progesterone and what the side effects are if a woman has too much.

Side effects of too much progesterone

Progesterone levels rise naturally during a woman's menstrual cycle, but if you're taking progesterone to balance hormones, prevent pregnancy, or have certain health conditions, then some side effects can occur.

Hormone replacement therapy side effects

Hormone replacement therapy (HRT) is commonly used to help alleviate perimenopausal and menopausal symptoms. One type of hormone therapy is progesterone replacement therapy. Women undergoing progesterone therapy may have side effects, including:


  •     Extreme tiredness
  •     Headaches
  •     Breast tenderness
  •     Mood swings
  •     Bloating
  •     Blurry vision
  •     Irritation at the application site


Menopause signals a time in a woman's life when she makes the transition from being able to conceive and becoming infertile. During this transition time, levels of estrogen and progesterone become imbalanced. Estrogen can become low, and progesterone levels rise. Menopausal symptoms vary in intensity and type but can include one or more of the following.


  •     Vaginal atrophy (dryness)
  •     Decreased sex drive
  •     Hot flashes
  •     Night sweats
  •     Insomnia
  •     Weight gain
  •     Depression
  •     Erratic moods

Managing these symptoms can be tricky because one proven method that works is hormone replacement therapy. However, due to a study in the 1990s by the Women’s Health Initiative (WHI), showing that older women undergoing HRT have increased risk for some health concerns. The increased risk included a higher chance of developing breast cancer, blood clots, and heart attacks.


Later research broke the results apart by revealing that, yes, for some women, there was an increased risk, but only for women over the age of 65. By 65, most women would have gone through menopause, making the risk very low for women undergoing BRT in their late 40s and early 50s.

How does HRT work?


Traditional HRT replaces the missing estrogen or progesterone with synthesized ones, usually made from horse urine. Another form of HRT is bioidentical hormone replacement therapy (BHRT). The main difference between traditional HRT and BHRT is that BHRT comes from extracting diosgenin from yam and soy plants.


The compound diosgenin is then synthesized into natural progesterone or estrogen. The result is a product that mimics the exact molecular structure of the progesterone produced in the ovaries. Your body cannot tell the difference between the progesterone you make and the ones derived in a laboratory.


Birth control pills side effects

A significant number of women begin taking birth control pills in their late teens and early 20s. Birth control pills help maintain higher levels of progesterone and estrogen in your body so that you don't ovulate. Without ovulation, there's no chance of conception. But like HRT, there can be some side effects if the formula isn't right.  The hormones in the pill can cause the following:


  •     unexplained weight gain
  •     Bloating
  •     Stomach ache or nausea
  •     Erratic moods
  •     Breakthrough bleeding (spotting when not menstruating)
  •     Breast tenderness or swelling

Most women take the pill to prevent pregnancy, but some women to treat acne, unpredictable periods, intense cramps, endometriosis, and


Birth control pills can treat fluctuating periods, cramps, acne, and polycystic ovary syndrome (PCOS).

Other side effects

Side effects of high progesterone may not be the result of pregnancy, BHRT, or taking birth control pills. It could be because there's an underlying health issue.


Adrenal cancer: It is a rare cancer that begins in the adrenal glands. The adrenal glands produce essential hormones, such as progesterone, estrogen, and testosterone. If cancer spreads beyond the adrenal glands, a cure is less likely.

Ovarian cancer: It's a type of cancer that begins in the ovaries. The ovaries are a vital part of a woman's reproductive system and help produce progesterone.

Ovarian cysts: They are pockets of fluid that develop on one or both of the ovaries. Most ovarian cysts don’t have symptoms and go away on their own.

Congenital adrenal hyperplasia: It's a rare, inherited disease that causes the adrenal glands not to function correctly, resulting in early puberty, infertility, and growth problems. If caught early, babies and children can lead a full and productive adult life.

How does progesterone work?


Progesterone is mainly produced in the ovaries by the corpus luteum, but lesser amounts in the adrenal glands. In the first two weeks of a woman's cycle, levels of progesterone are lower, and estrogen is higher. Estrogen is the sister hormone to progesterone, and together they are vital in menstruation. 

Once the ovary releases an egg, progesterone starts to develop the body for pregnancy. Around the released egg is the corpus luteum, which generates progesterone. If conception doesn't occur, progesterone levels fall, and a woman starts her period.

If conception occurs, then progesterone levels continue to grow to generate blood vessels for the endometrium or the lining of the womb. The endometrium is the fertile ground the fertilized egg needs to implant in the uterus. Progesterone is essential in this process for sustaining life and creating the placenta. Once the placenta takes over (at around 8-12 weeks), it regulates progesterone production.


Throughout pregnancy, progesterone continues to be essential for the following:

  • fetus development
  • creates maternal breast tissue
  • stops lactation
  • tightens the pelvic wall muscles to prepare for giving birth.


In the months leading up to having the baby, progesterone levels continue to rise. After labor and birth, levels fall again.



If you suspect you have too much progesterone, speak to your doctor about how to lower levels naturally. Living with the daily side effects diminishes the quality of your life.