So, you've heard that hormone replacement therapy for menopause symptoms and other purposes can have adverse health effects, and you're kind of scared to use it? You're not alone, and many women in your situation turn to so-called "natural" or "bioidentical" hormone replacement therapy, including progesterone.
What Is Bioidentical Progesterone (Natural Progesterone)?
Women had been using hormone replacement therapy — frequently to relieve menopause symptoms — more or less "like cookies" when a big health scare hit headlines near you in 2002. The Women's Health Initiative (WHI) trial of combined progestin and estrogen therapy found that the risk of fewer hip and vertebral fractures, as well as colorectal cancer, went down by a third in women taking hormone replacement therapy . Further research revealed that these protective benefits only lasted as long as women took the treatment, however . Follow-up analyses likewise revealed that women using combined estrogen and progesterone hormone replacement therapy had a higher risk of heart attack, stroke, blood clots, breast cancer, dementia, and urinary incontinence .
So, what's natural progesterone? The term "natural" generally refers to progesterone derived from naturally-occurring sources such as plants or animals, rather than synthesized in a lab. The term "bioidentical hormones" means something else — these hormones have the same molecular structure as those your body would produce on its own.
FDA-approved bioidentical progesterone therapies include Prochieve 4%, a vaginal gel, and Prometrium, which is taken in the form of tablets.  Many more products described as bioidentical or natural progesterone are sold on websites like Amazon, however, and they include a cream made by BIOlabs PRO, Kokoro Balance Cream, and even an oil called Progestelle.
Uses Of Progesterone Replacement Therapy
Many people will immediately associate the term "hormone replacement therapy" with the menopause. In combination with estrogen replacement therapy, progesterone replacement therapy can reduce unpleasant symptoms like hot flushes and menopause-induced vaginal dryness, as well as to protect against osteoporosis or brittle bones in the long run . Progesterone offers a protective effect that counteracts effects estrogen therapy might have when taken on its own, and helps prevent endometrial cancer and other uterine changes 
Progesterone is not just for women going through the menopause, however. You may also use it if:
- You have suffered repeated and unexplained miscarriages. 
- You are pregnant and at risk of preterm labor. 
- Your periods have stopped (amenorrhea), to induce them again. 
- You suffer from Premenstrual Dysphoric Disorder, a condition in which you become severely depressed before your period. 
- As a component of birth control pills.
While proponents of bioidentical progesterone, in particular, will claim that progesterone also prevents menstruation-related migraines, research has not confirmed this . Progesterone creams may, however, live up to another claim — that it can slow the aging process down and help your skin look younger and firmer .
Does Natural Progesterone Or Bioidentical Progesterone Effectively Reduce Menopause Symptoms?
Let's put it this way — one paper openly describes the term "bioidentical" as "pseudoscientific", and goes on to say:
"Natural alludes to the fact that these are native human hormones. In fact, these hormones are synthesized or semisynthesized." 
"Any menopausal hormone therapy should be reserved for women with bothersome symptoms, and used in the lowest effective dose for as brief a period as possible. Whereas compounded preparations may be useful for creating lower-dose preparations of hormones, these preparations lack the consistency and regulatory oversight required of commercial hormonal drugs." 
Another study adds that, while so-called natural progesterone medications appear to have little to no negative side effects, they're also not effective at managing the symptoms they are marketed as reducing .
The Bottom Line
If you are in need of progesterone replacement therapy, often in combination with estrogen replacement therapy, discuss the benefits and risks with your doctor. Also discuss the benefits of particular products, including those you can obtain without a prescription, with your healthcare provider before you start using them. Though words like "natural" and "bioidentical" may be appealing, they do not have science on their side — and neither are they necessarily any more natural or beneficial than the FDA-approved medications that have gone through rigorous testing.