Estradiol and Micronized Progesterone: A Narrative Review About Their Use as Hormone Replacement Therapy.
Level 5 - mechanism / opinion, no new human data
Narrative review without systematic methodology or meta-analysis
PubMed 41156198 · doi:10.3390/jcm14207328
What was done
This narrative review summarizes literature regarding hormone replacement therapy (HRT) regimens combining 17β-estradiol (E2) with micronized progesterone (P4). It evaluates physiological and clinical differences between micronized progesterone and synthetic progestins across multiple clinical endpoints, including endometrial thickness, venous thromboembolism, cardiovascular disease, breast cancer risk, cognitive function, bone protection, and quality of life.
What was found
The abstract provides a descriptive overview without reporting quantitative effect sizes, pooled risk estimates, or study counts. It notes that while synthetic progestins protect the endometrium, their broader systemic impacts are heterogeneous, whereas micronized progesterone is described as offering more physiological effects due to structural identity with endogenous progesterone.
Why it matters
Micronized progesterone is increasingly favored over synthetic progestins in clinical practice; this review outlines the mechanistic and clinical rationale across major organ systems.
Limits
The paper is a non-systematic narrative review without predefined inclusion criteria, risk-of-bias assessment, or quantitative data synthesis. Specific study numbers, sample sizes, and quantitative effect sizes are not reported in the abstract.
Cited by
- supports Standard pharmacy brand-name estradiol and micronized progesterone are bioidentical, whereas equine estrogens and synthetic progestins are not bioidentical.