Progesterone (micronised)

Bioidentical progesterone used in HRT. Oral dosing is sedating, which is why it is usually taken at night.

Medications & hormones

Research records

Historical source snapshot. Not freshly verified, not a recommendation. Study findings, community accounts and app defaults are not interchangeable.

Publication suitability · 2026-10-15: Historical reference only; not a clinical verification. Clinical, regulatory, efficacy, safety and dose claims are not independently established by this review.

Progesterone (micronised)

Bioidentical progesterone used in HRT. Oral dosing is sedating, which is why it is usually taken at night.

Evidence category: Regulator / guideline. This describes the source category, not approval or certainty.

Regulatory statement in source: FDA-approved.

Micronised progesterone is chemically identical to the body's own progesterone and has an FDA-approved label (Prometrium). The linked label covers protection of the womb lining against endometrial hyperplasia in women taking oestrogen, with trial figures over up to three years of treatment. That label version carries a boxed warning drawn from the Women's Health Initiative about cardiovascular risk, breast cancer and probable dementia with oestrogen plus progestin. A 2025 FDA press release announces the removal of warnings it describes as misleading from hormone replacement products.

Benefits reported in the imported source

Protect the womb lining in women on oestrogen, and for secondary amenorrhoea.
In the label trial, endometrial hyperplasia was 6% on the combination against 64% on oestrogen alone

Risks and limits

That label version carries a boxed warning on heart disease, breast cancer and probable dementia
A 2025 FDA press release announces removing warnings it calls misleading, so labelling is in flux

Source bottom line: Micronised progesterone is an approved medicine that protects the womb lining, with boxed warnings now under revision.

Uncertainty: Reference information only. Not medical advice.

Study protocols — reports, not instructions

postmenopausal women with a uterus receiving daily conjugated estrogens, per the US Prometrium label

Reported regimen: 200 mg micronised progesterone orally as a single daily dose at bedtime, for 12 days sequentially per 28-day cycle
Duration: ongoing, per the label
Reported outcome: The label lists this as the approved regimen for prevention of endometrial hyperplasia.
Source: PROMETRIUM (progesterone USP) FDA Label

Claim provenance

evidence.json#/catalog:hormone:progesterone/protocols/0

women with secondary amenorrhoea, per the US Prometrium label

Reported regimen: 400 mg micronised progesterone orally as a single daily dose at bedtime
Duration: 10 days
Reported outcome: The label lists this as the approved regimen for treatment of secondary amenorrhoea.
Source: PROMETRIUM (progesterone USP) FDA Label

Claim provenance

evidence.json#/catalog:hormone:progesterone/protocols/1

358 postmenopausal women with an intact uterus, in the randomised double-blind trial described in the label

Reported regimen: conjugated estrogens 0.625 mg a day plus Prometrium 200 mg a day for 12 days per 28-day cycle, against conjugated estrogens alone or placebo
Duration: up to 36 months
Reported outcome: Endometrial hyperplasia occurred in 6% on the combination against 64% on conjugated estrogens alone.
Source: PROMETRIUM (progesterone USP) FDA Label

Claim provenance

evidence.json#/catalog:hormone:progesterone/protocols/2

Community and practice descriptions

Accounts of a practice are not evidence of safety or effectiveness. Words such as “standard”, “safe” or “recommended” describe the source account, not verified consensus or this wiki’s advice. Commercial and self-published citations are retained for traceability, not vendor endorsement or independent clinical corroboration.

Unverified imported account — What Is The Lowest Dose of Progesterone For HRT?

An imported authored paraphrase, not a quotation or a recommended protocol.

Review: unverified historical account. The imported wording is preserved for attribution; its full clinical, dosing, efficacy or consensus claims have not been independently established. Unvalidated source account; no validated human dosing population or animal-to-human equivalence is inferred.

Imported wording: An HRT health platform reports that many women in their community begin with 100 mg of micronized progesterone taken nightly as an oral capsule, often combined with an estrogen patch.

What Is The Lowest Dose of Progesterone For HRT?

Pharmacokinetic context

No half-life recorded in this source snapshot. No value has been inferred.

Source references

Snapshot provenance

Source ID: catalog:hormone:progesterone. Commit: adc7684614f9439b41d91a3312b62e7982c7e20e. Review state: historical-not-reverified. Authored links are retained separately from the canonical evidence links in the public data. App templates/defaults and rejected drafts are archived, not deployed.

Related entries and components

None listed.