If you take estrogen for menopause and still have your uterus, you also need progesterone. Estrogen taken on its own thickens the uterine lining and raises the risk of endometrial cancer, and a progestogen added on top protects that lining. Women who have had a hysterectomy generally do not need it.

Key takeaways

  • Estrogen stimulates the uterine lining (the endometrium). Over time, unopposed estrogen raises the risk of endometrial hyperplasia and endometrial cancer. Progesterone opposes that growth, which is the reason the two are paired.
  • If you have a uterus, you need a progestogen alongside systemic estrogen. If you have had a hysterectomy, estrogen alone is the standard, and progesterone is usually not required for protection.
  • Progesterone is body-identical (the same molecule your ovaries make), unlike older synthetic progestins. The common oral form is micronized progesterone, and the FDA-approved brand is Prometrium. Therisse dispenses a compounded oral progesterone (100 mg), which is not FDA-approved.
  • It is taken at bedtime because it can cause drowsiness. Therisse's standard pairing is 100 mg daily; a cyclic 200 mg for 12 to 14 days each month is the alternative with the strongest trial evidence.
  • Progesterone creams are not a reliable way to protect the lining: blood levels stay too low. Protection needs an adequately absorbed form, usually oral.
  • Hormone therapy still carries real risks: blood clots, stroke, breast cancer. A physician reviews your history before it is prescribed.

Most of the menopause conversation is about estrogen, because estrogen is what relieves hot flashes, night sweats, and the other symptoms. Progesterone is the quieter half of the prescription, and its main job is not symptom relief, it is safety: protecting the uterus from what estrogen does to it. This page explains why the two go together, who actually needs progesterone, how it is dosed, and what to expect. It is a companion to the biest cream overview and the biest cream vs estradiol patch comparison, which cover the estrogen side.

Why is progesterone prescribed with estrogen?

Estrogen makes the lining of the uterus grow. On its own, with nothing to balance it, that growth can become excessive: first endometrial hyperplasia (an overgrowth of the lining), and over time an increased risk of endometrial cancer. This is well established, and it is why major medical bodies, including the American College of Obstetricians and Gynecologists (ACOG) and The Menopause Society, recommend that any woman with a uterus who takes systemic estrogen also take a progestogen.

Progesterone (or a synthetic progestin) opposes estrogen's effect on the lining. It moves the endometrium out of the constant "grow" signal and keeps that cancer risk from climbing. Put simply: estrogen treats the symptoms, and progesterone protects the organ that estrogen would otherwise overstimulate.

Do you need progesterone if you don't have a uterus?

Usually no. If you have had a hysterectomy and no longer have a uterus, there is no endometrial lining to protect, so the main reason for taking progesterone does not apply. The standard of care for women without a uterus is estrogen alone.

Two honest caveats:

  • Some clinicians still prescribe progesterone after a hysterectomy for other reasons (for example, some women find it helps with sleep). That is an individual decision, not a protection requirement.
  • If a procedure left the uterus in place or left endometrial tissue behind, the protection rule still applies. This is exactly the kind of detail a physician confirms from your history.

This is why the Therisse intake asks about your uterus status up front. It is one of the few answers that genuinely changes the prescription.

What is micronized progesterone, and how is it different from progestins?

"Micronized" means the progesterone is ground into very fine particles so the body can absorb it when taken by mouth. It is body-identical: the same molecule your ovaries produce. The FDA-approved brand is Prometrium, whose label states the progesterone in it is "identical to progesterone of ovarian origin."

That is different from synthetic progestins (such as medroxyprogesterone acetate, the "MPA" in older studies), which are lab-made compounds that act like progesterone but are not the same molecule. Both protect the endometrium. Where they appear to differ is the breast cancer signal: in the large French E3N cohort study, estrogen combined with synthetic progestins was associated with an increased breast cancer risk (relative risk about 1.4), while estrogen combined with micronized progesterone was not (relative risk about 0.9).

It is worth being careful about how much that carries. E3N is observational, not a randomized trial, and it speaks mostly to shorter-term use. It is a reason many clinicians prefer micronized progesterone, not a promise that it is risk-free. Hormone therapy still carries a real breast cancer risk overall.

Micronized progesterone dosing

Oral progesterone is usually taken at bedtime, on purpose. It can cause drowsiness and dizziness, and the FDA label for the micronized form (Prometrium) specifically directs bedtime dosing to limit those effects. Taking it at night turns a side effect into a non-issue for most women.

Two common regimens:

  • Continuous: 100 mg taken every day. This is Therisse's standard pairing with biest, and once it settles, most women have no monthly bleeding.
  • Cyclic: 200 mg for 12 to 14 days each month. This regimen has the strongest randomized-trial evidence for endometrial protection and usually produces a scheduled monthly bleed.

There is no single number that is right for everyone. The regimen depends on your estrogen dose and your history, which a board-certified physician reviews before prescribing.

Progesterone side effects

The most common, especially in the first few weeks:

  • Drowsiness or dizziness (the reason for bedtime dosing)
  • Breast tenderness
  • Bloating or fluid retention
  • Mood changes
  • Spotting, or a scheduled monthly bleed, depending on the regimen

Most are mild and ease as your body adjusts. The Prometrium label notes that some women get more pronounced dizziness or drowsiness when starting, so it is sensible not to drive right after your first few doses until you know how it affects you.

Why a progesterone cream usually isn't enough

A common question is whether a progesterone cream can do the job instead of a capsule. For some symptom uses, women do apply them, but for protecting the uterine lining, creams are not reliable. Studies that measured blood levels after topical progesterone consistently found them too low to keep the lining in check. A review of topical progesterone creams and gels concluded they do not reach the levels needed to oppose estrogen on the endometrium.

That is the practical reason Therisse pairs biest with an oral progesterone capsule rather than a progesterone cream: if you have a uterus, the form that protects it has to actually be absorbed.

The risks, stated plainly

Adding progesterone is about reducing one specific risk, endometrial cancer from unopposed estrogen. But hormone therapy as a whole still carries its own established risks: blood clots, stroke, and breast cancer. Progesterone does not erase those. What it does is keep estrogen from creating a new problem in the uterus. A physician reviews your full history, including any personal or family history of clots, stroke, or hormone-sensitive cancers, before any of this is prescribed.

How Therisse handles this

When you choose the combined option at checkout (estrogen plus progesterone), Therisse pairs compounded biest cream with oral progesterone, 100 mg taken daily (an immediate-release capsule). Both are dispensed by a licensed 503A compounding pharmacy after a board-certified physician reviews your intake and history, including your uterus status. If you have had a hysterectomy, the estrogen-only option is the standard path, and the intake captures that.

On FDA status, in plain terms: the compounded progesterone Therisse dispenses is not FDA-approved, the same as compounded biest. Micronized progesterone does have an FDA-approved version (Prometrium); a compounded capsule made for an individual patient is a different regulatory category. (More on what "compounded" means in the biest cream overview.)

Prescription products require an online consultation with a licensed provider. If a physician does not approve you, your initial consult fee and any medication charge are refunded in full.

Compounded products are not FDA-approved. This page is educational and is not medical advice. Hormone therapy is not right for everyone, and it carries risks including blood clots, stroke, and breast cancer. Talk to a licensed clinician about your individual history.

Frequently asked questions

Why do you have to take progesterone with estrogen? If you have a uterus, estrogen taken alone overstimulates the uterine lining and raises the risk of endometrial cancer. Progesterone opposes that effect and protects the lining, which is why the two are prescribed together.

Do you need progesterone if you don't have a uterus? Usually no. After a hysterectomy there is no uterine lining to protect, so estrogen alone is the standard of care. Some clinicians still prescribe progesterone for other reasons, but it is not required for protection.

Is micronized progesterone better than a synthetic progestin? Both protect the endometrium. Micronized progesterone is body-identical and, in the observational E3N study, was not linked to the increased breast cancer risk seen with synthetic progestins. That evidence is not from a randomized trial, but it is why many clinicians prefer it.

What is the dose of progesterone with estrogen? Commonly 100 mg of oral progesterone taken daily (continuous), or 200 mg for 12 to 14 days each month (cyclic). It is taken at bedtime because it can cause drowsiness. The right regimen depends on your estrogen dose and history.

Can I use a progesterone cream instead of a capsule? Not for protecting the uterine lining. Studies show progesterone creams do not raise blood levels enough to reliably oppose estrogen on the endometrium. If you have a uterus, an adequately absorbed form, usually oral, is needed.

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