Continuous vs. Cyclic HRT: Understanding Your Dosing Options

Educational only. Not medical advice. The choice between cyclic and continuous dosing depends on your menopausal stage and clinical history. Discuss with your clinician.

If you have a uterus, you need progestogen alongside estrogen. How you take that progestogen - every day or part of each month - determines whether you have monthly withdrawal bleeds, how your body adjusts, and what the first six months of treatment feel like. This is not a minor administrative detail. It is one of the first decisions you and your clinician will make, and understanding the tradeoffs helps you choose the approach that fits your life.

Estrogen is taken daily throughout the month. Progestogen is added for 10 to 14 days of each cycle. When the progestogen stops, the uterine lining sheds in a predictable withdrawal bleed. This bleed is not a menstrual period in the ovulatory sense - it is a progesterone-withdrawal bleed designed to protect the endometrium.

Cyclic regimens are typically used for perimenopausal women and those in early postmenopause whose bodies are still adjusting to the hormonal transition. The scheduled bleed aligns with what the body was recently doing naturally.

Practical calendar example: estradiol 1mg daily (every day of the month). Progesterone 200mg at bedtime on calendar days 1-12. Expect withdrawal bleed approximately days 13 to 17. Resume progesterone on day 1 of the next month.

Both estrogen and progestogen are taken every day without a break. The goal is to keep the uterine lining thin and stable, which ideally results in no monthly bleeding.

Continuous combined regimens are typically used for women who are at least one to two years past their final menstrual period. Starting continuous combined therapy too early in the menopausal transition increases the likelihood of unpredictable bleeding.

Practical calendar example: estradiol 1mg daily (every day). Progesterone 100mg at bedtime (every day). No planned withdrawal bleed.

On continuous combined therapy, breakthrough bleeding occurs in up to 40 to 50% of women in the first 3 months. This is the endometrium adjusting to continuous progestogen suppression. It is expected, not alarming.

Months 1 to 3: spotting or light bleeding is normal. Do not stop therapy. Do not change your regimen. Most women find the episodes become lighter and less frequent over this window.

Months 3 to 6: bleeding should be decreasing. If it is not improving or is worsening, contact your clinician. A dose or formulation adjustment may help.

After 6 months: bleeding that persists, restarts after a bleed-free period, is heavy, or is accompanied by pain warrants endometrial evaluation - typically transvaginal ultrasound measuring endometrial thickness and possibly endometrial biopsy to rule out hyperplasia or malignancy.

On cyclic therapy: withdrawal bleeding during the progestogen-free days is by design. Expect it 1-3 days after the last progestogen dose. The bleed should be predictable in timing and moderate in volume. Bleeding outside the expected window, very heavy bleeding, or bleeding that changes significantly should be reported.

Many women begin on a cyclic regimen and later transition to continuous combined therapy as they move further into postmenopause. The transition typically happens when the woman has been without natural periods for 1 to 2 years (excluding the cyclic withdrawal bleeds).

Some breakthrough bleeding during the transition is expected. The switch involves stopping the cyclic progestogen pattern and starting daily combined dosing. Give it 3 to 6 months to stabilize before concluding it is not working.

For women who have had a hysterectomy, the cyclic-versus-continuous distinction does not apply because progestogen is not needed to protect a uterine lining that no longer exists. Estrogen-only therapy is taken continuously. No progestogen phase, no withdrawal bleeds.

Exception: a clinician may still recommend progestogen after hysterectomy for women with a history of endometriosis, where residual endometriotic tissue could be stimulated by unopposed estrogen.

Practical Calendar Example

Cyclic regimen example: estradiol 1mg daily (every day of the month). Progesterone 200mg at bedtime on calendar days 1-12. Expect withdrawal bleed approximately days 13 to 17. Resume progesterone on day 1 of the next month.

Continuous regimen example: estradiol 1mg daily (every day). Progesterone 100mg at bedtime (every day). No planned withdrawal bleed. Spotting in the first months is expected and resolves.

• Which regimen type are you recommending for my menopausal stage and why?
• What bleeding pattern should I expect, and what changes should I report?
• When should I transition from cyclic to continuous?
• If breakthrough bleeding persists, what evaluation will you do?