From the Guidelines
The ideal progesterone to estrogen ratio should be prioritized based on the safest and most effective progestin, with natural micronized progesterone (MP) being a favorable option due to its minimal hormonal-related cardiovascular risks and neutral effect on blood pressure, as demonstrated in recent studies 1. When considering the progesterone to estrogen ratio, it is essential to focus on the type of progestin used, as different progestins have varying effects on cardiovascular risk, lipid profiles, and carbohydrate metabolism.
- Medroxyprogesterone acetate (MPA) has been shown to negatively impact cardiovascular risk, but it is still considered a first-choice option due to its wide availability of data on efficacy 1.
- Natural micronized progesterone (MP), on the other hand, has a more favorable profile, with studies demonstrating its ability to minimize hormonal-related cardiovascular risks and have a neutral or beneficial effect on blood pressure 1.
- The European Society for Human Reproduction and Embryology (ESHRE) recommends MP as a progestogen in HRT in adult women with ovarian insufficiency, highlighting its safer pharmacological profile 1. The choice of progestin and estrogen dose is crucial in determining the progesterone to estrogen ratio, and clinicians should consider the advantages and disadvantages of different regimens, including sequential and continuous administration, when prescribing HRT.
- The dose of progestogen is based on the concurrent dose of estrogen administered, and the cyclic administration of HRT allows for earlier recognition of pregnancy in women with premature ovarian insufficiency (POI) 1.
- Ultimately, the goal is to achieve a balance between progesterone and estrogen levels to support reproductive health, mood stability, and overall hormonal wellness, and natural micronized progesterone (MP) appears to be a promising option in achieving this balance 1.
From the Research
Progesterone Estrogen Ratio
- The progesterone estrogen ratio is not directly discussed in the provided studies, however, the effects of different progesterone and estrogen combinations in oral contraceptives are examined 2, 3, 4, 5.
- Studies have investigated the use of levonorgestrel (LNG) and ethinyl estradiol (EE) in combined oral contraceptives, including extended-cycle regimens 2, 3.
- The pharmacokinetics and pharmacodynamics of EE and 17β-estradiol (E₂) in combined oral contraceptives have been reviewed, including their metabolism, adverse effects, and potential benefits 5.
- Progesterone has been shown to play a crucial role in pregnancy maintenance, including modulation of maternal immune response, reduction of uterine contractility, and improvement of utero-placental circulation 6.
- The optimal dosage and route of administration of progesterone are important considerations, with oral, vaginal, and intramuscular administration being commonly used 6.
- Plasma hormone levels, including FSH, LH, estradiol, and progesterone, have been evaluated in women receiving new oral contraceptives containing EE plus LNG or desogestrel, showing decreased levels incompatible with ovulation 4.