Progestogen

• In some women, progestogens cause physical or psychological side effects. See above table.
• This is often called ‘progestogen intolerance’ or 'progesterone intolerance' and is estimated to affect about 20% of women.
• Symptoms tend to occur in a cyclical pattern if a sequential regime is being used.
• A history of premenstrual syndrome (PMS), premenstrual dysphoric disorder (PMDD) or a bad reaction to contraception in the past might point towards progestogen intolerance.

STRATEGIES TO REDUCE PROGESTOGEN INTOLERANCE INCLUDE:

1. TIME

• For women with mild progestogen intolerance, symptoms often improve with time, usually after 2 – 3 months.

2. TRYING AN ALTERNATIVE PROGESTOGEN

• Women differ in their tolerability to progestogens. If side effects occur with one type of progestogen, consider trying another. Most women can find a progestogen they get on with.
• In general, micronised progesterone and dydrogesterone have fewer side effects compared to other progestogens due to their selective affinity for the progesterone receptor. Dydrogesterone is only available in the oral preparation Femoston.
• A 52mg levonorgestrel intrauterine device (LNG IUD) is another option that can be better tolerated due to its localised action, resulting in low systemic levels of levonorgestrel.
• Androgenic side effects such as acne and hirsutism may be more associated with the use of testosterone derived progestogens such as norethisterone and levonorgestrel due to stimulation of the androgen receptors.

3. ADJUSTING TIMINGS

• This is mostly relevant to micronised progesterone because unlike other progestogens, this can be sedating. Patients should be advised to take this at night.
• Taking progesterone on an empty stomach can reduce side effects. This is because there is an increased absorption when progesterone is taken with food.

4. VAGINAL PROGESTERONE

• Vaginal progesterone can be considered in women who experience progestogenic side-effects with oral intake. Side effects may be reduced taking it in this way.
• Options include lutigest pessaries, cyclogest pessaries, vaginal Utrogestan and vaginal administration of oral micronised progesterone capsules.
• Women should be informed that these preparations are unlicensed.
• Intake should follow the same doses recommended with oral intake.
• For more information, see section in prescribing information.

5. DOSE REDUCTION

• The progestogen dose should not be routinely reduced.
• Studies have shown that shorter durations and lower doses of progestogen are likely to be associated with an increased risk of endometrial hyperplasia and endometrial cancer.
• Any decision to reduce the progestogen dose should be undertaken after discussion with a menopause specialist.
• Women using low progestogen doses may require endometrial surveillance, and there should be a low threshold to investigate any change in bleed pattern.