Progesterone
Progesterone is used with estrogen in menopause HRT for uterine protection. Bioidentical Prometrium also has a sedating effect that often improves sleep.
How it works
Estrogen without a progestogen causes the uterine lining to thicken (endometrial hyperplasia), which over time raises the risk of endometrial cancer. Adding progesterone or a synthetic progestin prevents this. Bioidentical progesterone — chemically identical to the progesterone produced by the ovaries — is available as FDA-approved Prometrium (oral micronized progesterone) or through compounding pharmacies. FDA-approved micronized progesterone is generally preferred over compounded versions because its potency and purity are regulated.
Bioidentical progesterone has a distinct characteristic that synthetic progestins lack: it metabolizes into neurosteroids that interact with GABA receptors in the brain, producing a calming and sedating effect. This makes evening dosing advantageous for many people, as it can meaningfully improve sleep quality. This sleep benefit is specific to bioidentical progesterone and is not seen with synthetic progestins like medroxyprogesterone or norethindrone. Side effects can include dizziness, drowsiness (usually beneficial when taken at bedtime), and mood changes.
How to track Progesterone
- Dosing timing and consistency — progesterone is typically taken in the evening; logging when you take it reveals whether timing correlates with sleep benefit.
- Sleep quality: time to fall asleep, number of nighttime wakings, and how you feel in the morning — the sedative effect is one of progesterone's most useful characteristics.
- Mood and emotional stability — progesterone affects GABA signaling and some people notice improved calm or conversely mild mood changes.
- Side effects: dizziness, next-day grogginess, breast tenderness, or bloating.
- Breakthrough bleeding or spotting if on a sequential regimen — bleeding patterns are diagnostically important and should be logged carefully.
- Log the time you use progesterone each evening — the sedating effect is most useful when consistently timed with your sleep window.
- Rate sleep quality on a consistent scale each morning so you can see whether the sedative effect is contributing to improvement alongside any hot flash reduction.
- Log mood and anxiety separately from sleep — both may change with progesterone and the patterns are worth distinguishing.
- If you're on a cyclic regimen (progesterone only part of the month), log the days you use it alongside any mood or bleeding pattern changes that occur on the off days.
- Note dizziness or next-day grogginess with the timing of your dose — if it's occurring, adjusting the time of evening dosing may help.
Questions to ask your physician
- My sleep quality log shows [pattern] since starting progesterone — is the sedating effect working as expected, or does that suggest a dose timing adjustment?
- I've been logging breakthrough bleeding on [dates and description]. What does that pattern indicate?
- My mood tracking shows [pattern] alongside progesterone use — is that consistent with the expected neurosteroid effect?
- I've been logging dizziness at [timing] — does that suggest I should adjust when in the evening I take it?