Progesterone plays a vital role in a woman's reproductive cycle. Produced by the corpus luteum, the leftover part of the follicle that contains the developing egg before ovulation, progesterone readies the uterine lining for implantation of an embryo each month. If no pregnancy occurs, the corpus luteum disintegrates, progesterone levels drop and a new menstrual cycle begins. Women take synthetic progesterone supplements in oral contraceptives and hormone replacement therapy. Natural progesterone supplements are sometimes taken to boost progesterone levels in pregnancy and to treat menopausal symptoms.
Types
Natural progesterone is produced by the adrenal glands, corpus luteum and placenta in the body. Natural progesterone can also be given in prescription injectable form, pills and creams. The term "natural progesterone" is also used to describe progesterone obtained from plant sources such as yams that are used in over-the-counter creams. Natural progesterone creams may also contain progesterone synthesized from wild yam or soy in the laboratory that is then added to the creams. These should more accurately be called synthetic, since they're made in the lab, NYU Langone Medical Center states. Synthetic progesterone found in birth control pills and hormone replacement therapy, more accurately called progestin, has a different chemical structure than natural progesterone.
Differences and Similarities
Prescription natural progesterones raise the levels of progesterone in the blood in the same way progesterone produced in the body does. Prescription progestins do not raise progesterone levels. Over-the-counter progesterone creams that contain wild yam do not contain progesterone, but rather diosgenin. In the laboratory, diosgenin can be made into progesterone, but your body can't convert diosgenin to progesterone, which gives it no value as a progesterone supplement. Progesterone over-the-counter creams synthesized from wild yam or soy can raise progesterone levels. A study conducted by researchers from Bassett Healthcare compared progesterone levels in women taking 200 mg oral prescription progesterone to those using over-the-counter "natural" creams containing 40 mg for 12 days. No significant difference in progesterone levels was noted between the two, according to the June 2005 issue of the "Journal of Clinical Pharmacology."
Side Effects
Prescription forms of natural progesterone and progestins cause the same side effects that occur from progesterone made by the body. Headache, fluid retention, weight gain, acne, diarrhea, tiredness, mood swings, breast pain, muscle or joint pain, and irritability are common side effects of progesterone. Over-the-counter creams can cause similar symptoms, according to Creighton University.
Concerns
Over-the-counter products are not well-regulated; the amount of progesterone contained in an over-the-counter supplement may vary. Progesterone use can cause serious complications such as an increased risk of blood clots or stroke. Researchers from Basset Healthcare expressed concern over women taking a potentially harmful drug as an over-the-counter supplement. Progesterone should be used only under your doctor's supervision, NUY Langone Medical Center states.
References
- NYU Langone Medical Center; Progesterone; February 2011
- MedlinePlus; Progesterone; September 2008
- Creighton University: Natural Progesterone
- "Journal of Clinical Pharmacology"; Over-the-Counter Progesterone Cream Produces Significant Drug Exposure Compared to a Food and Drug Administration-Approved Oral Progesterone Product; A. Hermann et al.; June 2005
