03/12/2026
As an integrative nurse practitioner, one of the biggest misconceptions I see is the belief that all “progesterone” is the same. It’s not.
There is a major difference between bioidentical progesterone and synthetic progestins commonly found in hormonal birth control and some hormone therapies.
Here are a few key distinctions:
Bioidentical Progesterone
• Structurally identical to the progesterone your body naturally makes
• Supports ovulation and normal menstrual cycle signaling
• Often promotes calming effects in the brain through GABA receptors
• Can support sleep, mood balance, and healthy hormone signaling
•Anti cancer properties and decreases overall inflammation
Synthetic Progestins
• Structurally different from human progesterone
• Designed to suppress ovulation, which eliminates ovulation as a hormonal signal. Our menstrual cycle is our 5th vital sign.
• Can bind to androgen and estrogen receptors, creating effects that natural progesterone does not (weight gain, acne, oily skin, low libido)
• Associated in research with changes in mood, anxiety, and depressive symptoms in some women
• Certain formulations used in hormone therapy have been linked in studies to increased cardiovascular and breast cancer risk
Because of these structural differences, synthetic progestins do not act the same way in the body as true progesterone.
Hormones are powerful messengers, so the type and structure matter.
If you’re navigating hormone therapy, birth control decisions, or hormone symptoms, understanding these differences is important so you can make informed choices about your health.
