Progesterone Intolerance

Progesterone, a hormone produced by the ovaries, plays a crucial role in regulating your menstrual cycle and supporting fetal development during pregnancy. Additionally, it works in tandem with oestrogen, with each hormone having interconnected functions. In the absence of progesterone, oestrogen thickens the uterine lining, while progesterone maintains a thin, healthy lining. Maintaining the right balance of oestrogen and progesterone throughout your menstrual cycle is essential for regular, trouble-free periods and fertility.

Artificial progesterone has been developed for use in certain medications and is present in most hormonal contraceptives, including the combined pill, mini-pill, contraceptive implants, injections, and the hormonal coil (Mirena). Artificial or synthetic progesterone is referred to as progestogen or progestin.

Some women may experience heightened sensitivity or adverse reactions to their natural progesterone or, more commonly, to synthetic progestogen. This sensitivity to progesterone can often go unnoticed until women begin using specific contraceptives or take progesterone as part of hormone replacement therapy (HRT).

What is progesterone intolerance?

Progesterone intolerance describes a specific set of symptoms that occur in response to this sensitivity to progesterone or progestogen in the body. These symptoms often resemble those of premenstrual syndrome (PMS) since natural progesterone levels are at their highest during this phase of the menstrual cycle.

Symptoms affect approximately 10-20% of women, and most of these individuals are using hormonal contraceptives or HRT containing progestogen. These symptoms can be categorised as psychological, physical, or, in rare instances, metabolic (affecting metabolism, leading to changes in cholesterol levels, blood sugar, or blood pressure). 

Psychological Symptoms

Panic attacks
Low mood
Heightened emotions, including irritability and aggression 
Forgetfulness and difficulty concentrating

Physical Symptoms (resembling PMS):

Abdominal cramping or bloating
Fluid retention
Breast tenderness
Skin changes, such as acne and increased skin oiliness

Progesterone as part of HRT

If you still have your uterus (womb) and are taking oestrogen to alleviate perimenopausal or menopausal symptoms, you will typically be advised to also use a progesterone treatment. This counteracts the thickening effect of estrogen on the uterine lining and helps maintain the health of uterine cells. This combination of oestrogen and progesterone is referred to as ‘combined HRT.’

Progesterone is usually administered in combined HRT through two main methods:

  • oral capsules (commonly Utrogestan) or
  • the insertion of a Mirena coil into the uterus.

Utrogestan capsules chemically mimic the body’s natural progesterone and are associated with the lowest risks.

The type of progesterone (progestogen) used in the Mirena (and many contraceptives) is still considered safe but may not be as safe as Utrogestan in terms of certain risks, including blood clots, heart or blood vessel diseases, and breast cancer. However, these risks are extremely small and influenced more by overall health, weight, lifestyle, and genetics than the type of progesterone treatment used.

When you might notice symptoms of progesterone intolerance?

If you’ve had a period within the last 6-12 months, you’re likely on a cyclical regimen with Utrogestan, taking it for two weeks each month and not taking it for two weeks (during which you may have bleeding). You may notice that your symptoms are more pronounced during the weeks when you’re taking Utrogestan and improve during the weeks when you’re not.

If it’s been more than 12 months since your last period, you might be on a continuous regimen, taking progesterone daily. Symptoms may have started or intensified when you began Utrogestan, and for some women, they persist as long as they continue the treatment.

It’s common for women to experience some of the described symptoms when the Mirena coil is first inserted, and these symptoms may persist for a few months. Typically, they subside as the body adapts to the hormonal changes.

If symptoms do not improve after 6 months, consult the healthcare professional who fitted the coil to discuss whether you should continue with it or explore alternative progesterone options for your HRT.

What can you do if you have symptoms of progesterone intolerance?

Keep a record of your symptoms and the dates when you start or stop progesterone treatments, and discuss them with a healthcare professional who can explain alternative options based on your specific situation.

Progesterone intolerance symptoms may be more prominent when you first start HRT, but they often improve with time as oestrogen levels increase and there are various progesterone types and administration methods to explore. Consult your menopause specialist before giving up on HRT entirely to ensure you don’t miss out on its other potential benefits. 

Consider trying Utrogestan, which is often better tolerated by women.

Adjust the dose or the number of days you take it, in consultation with your doctor, to balance uterine protection and symptom management.

Use Utrogestan vaginally for targeted absorption into the uterus, reducing systemic absorption and potential side effects.

Explore other progesterone treatments designed for vaginal insertion, such as Cyclogest or Lutigest, if you prefer localised treatment over systemic options.

Consider the Mirena coil, which provides adequate progestogen for HRT and is inserted directly into the uterus.

Modify lifestyle factors that can affect progesterone receptor sensitivity in the brain, such as alcohol, nicotine, dietary elements like sugar and dairy products, and stress.