Micronized progesterone: benefits, timing, and side effects

Micronized progesterone protects the uterine lining from the thickening effect of estrogen, and is required for anyone with a uterus who takes systemic estradiol. It is body-identical, usually taken as a bedtime capsule, and its mild sedative effect often helps with sleep. Women who have had a hysterectomy generally do not need it.

What does micronized progesterone do?

Its primary job is endometrial protection. Estradiol relieves hot flashes, night sweats, and other menopause symptoms, but on its own it stimulates the uterine lining. Adding progesterone keeps the lining in check. This is why women with a uterus take both hormones, while women who have had a hysterectomy generally take estradiol alone. Womea offers it as Micronized Progesterone capsules, the same body-identical hormone the body produces.

Why micronized progesterone, specifically?

"Micronized" means the progesterone is ground into very fine particles so the body can absorb it well. It is body-identical, meaning its molecular structure matches the progesterone your ovaries once made — unlike older synthetic progestins. Body-identical micronized progesterone is generally well tolerated and is the progesterone most current guidelines favor for menopause care. It is the guideline-favored form, which is why we lead with it rather than compounded alternatives.

When should you take it: cyclic or continuous?

There are two common schedules, and your clinician will match one to where you are in the menopause transition.

• Continuous: a lower dose taken every night, which usually leads to no monthly bleeding over time and suits women who are clearly postmenopausal
• Cyclic: a higher dose taken for about 12 to 14 days each month, which produces a predictable monthly bleed and is often used in perimenopause
• Taken at bedtime in either case, since it can cause drowsiness — an effect many women find helpful for sleep

What side effects should you expect?

Most side effects are mild and ease over the first weeks. Because micronized progesterone is suspended in peanut oil in some formulations, women with a peanut allergy should flag it — a vaginal route or an alternative may be appropriate.

• Drowsiness or a calm, sleepy feeling, usually welcome at bedtime
• Mild dizziness, breast tenderness, or bloating in the first weeks
• Mood changes in some women, which are worth tracking and reporting
• Spotting or irregular bleeding, especially early on or with continuous dosing

Report any new, heavy, or persistent bleeding to your clinician, since the uterine lining needs to be checked. Compounded combinations such as Biest 50:50 + Progesterone are chosen with a clinician in specific situations, but compounded progesterone is not safer or more effective than the standard micronized form, and the same protective role and timing principles apply.