Progesterone Capsules

Estrogen alone causes the uterine lining to thicken. Without something to oppose it, that thickening can lead to abnormal bleeding and, over time, to a meaningful increase in endometrial cancer risk. Progesterone signals the lining to shed or stay thin — whichever the regimen is built for. For any woman with a uterus on systemic estrogen, that opposition isn't optional.

Micronized progesterone is bioidentical — structurally the same as the progesterone your ovaries made. The Women's Health Initiative findings that complicated HRT's reputation in 2002 were largely driven by a synthetic progestin (medroxyprogesterone), not bioidentical progesterone. The current consensus is that micronized progesterone has a more favorable breast and cardiovascular profile.

Beyond endometrial protection, oral progesterone is metabolized into compounds that act on GABA receptors — the same receptors anti-anxiety and sleep medications work on. Many women report it helps them fall asleep more easily and wake less often. That's why nightly dosing is the default.

Most common: drowsiness within 1–2 hours of dosing (usually welcome at bedtime), mild dizziness if you stand quickly after taking it, occasional vivid dreams. These typically settle and most women find them mild.

Less common but worth flagging: low mood, breast tenderness, breakthrough bleeding past the first 3 months, persistent fatigue. Tell your clinician — the schedule or strength is usually adjustable.

Not appropriate if: you have a personal history of breast cancer, certain hormone-sensitive cancers, active liver disease, a history of blood clots, unexplained vaginal bleeding, or you're pregnant. Allergy to peanuts is a contraindication for some formulations (the capsules contain peanut oil) — tell your clinician. Your assessment surfaces these factors carefully.