Progesterone Administration Guidelines

Introduction to Progesterone Regimens

The American College of Obstetricians and Gynecologists recommends progesterone administration for 12-14 days per month when used in a sequential regimen with estrogen therapy, particularly in patients with premature ovarian insufficiency (POI) or those requiring endometrial protection 1, 2, 3

The Endocrine Society recommends a sequential regimen for patients who accept or prefer withdrawal bleeding 3
A sequential regimen typically involves transdermal 17β-estradiol administered continuously for 28 days, and oral/vaginal progesterone administered for 12-14 days every 28-day cycle 2, 1
Standard adult doses in sequential regimens include 200 mg of oral or vaginal micronized progesterone for 12-14 days every 28 days 1, 10 mg of medroxyprogesterone acetate for 12-14 days per month 2, or 10 mg of dydrogesterone for 12-14 days per month 1
The American College of Obstetricians and Gynecologists recommends a continuous regimen for patients who prefer to avoid withdrawal bleeding, involving continuous administration of both estrogen and progesterone without interruption 3
Standard adult doses in continuous regimens include a minimum of 1 mg of oral norethisterone, 2.5 mg of oral medroxyprogesterone acetate, or 5 mg of oral dydrogesterone daily 2, 1

Micronized progesterone is the first choice among progestins due to its lower risk of cardiovascular disease and venous thromboembolism when taken cyclically, and better safety profile regarding metabolic effects, breast cancer risk, and thromboembolism risk 1
The Endocrine Society recommends avoiding progestins with anti-androgenic effects in patients with POI who may already suffer from diminished libido or impaired sexual function 1

The decision algorithm for progesterone administration involves determining the clinical indication, considering patient preferences, selecting an appropriate formulation, and administering at the appropriate time, with micronized progesterone as the first choice 1, 3

The Human Reproduction Update reports that common initial side effects of progesterone therapy, such as mood changes, breast tenderness, bloating, and breakthrough bleeding, typically resolve within the first 3 months 4
Breakthrough bleeding, especially in sequential regimens, is a common side effect that usually resolves within the first 3 months, as noted by the Human Reproduction Update 4

The administration route of progesterone impacts the adjustment time, with transdermal progesterone in combined patches having a more gradual onset with fewer side effects, according to Blood Reviews 5

Patients should have a clinical review after 3 months of therapy to assess symptom improvement, side effect profile, and compliance with therapy, as recommended by the Human Reproduction Update 4
The Human Reproduction Update suggests that no routine monitoring tests are required during the adjustment period unless prompted by specific symptoms or concerns 4

If significant side effects persist beyond 6 months, alternative progesterone formulations or dosing regimens should be considered, as advised by the Human Reproduction Update 4

The Centers for Disease Control and Prevention recommends that sequential regimens should not be confused with the Standard Days Method (days 8-19 for fertility awareness), which is unrelated to hormone replacement therapy 6, 7, 8

The American College of Obstetricians and Gynecologists implies that never using progestin for less than 12 days per cycle in sequential regimens is crucial, as this significantly increases endometrial hyperplasia and cancer risk, with a relative risk of 1.8 for endometrial cancer if progestin use is less than 10 days per cycle 6, 7, 8