Progesterone is a progestogen. Progestogens are a group of hormones which work in a similar way to progesterone - but only progesterone itself is natural. All the others in this group are synthetic. If progesterone is taken in the form of medication by mouth, the liver quickly breaks it down.

In 1934 a synthetic form was created to get round this problem. There are now over 10 synthetic progesterones available. The newest is a micronized version. Micronized means that the progesterone has been broken down into microscopic particles and avoids breakdown by the liver.

What Are Progestogens Used For?

If a woman has a condition which leads to her ovaries failing to work, natural progesterone won't be made in sufficient quantities. Progestogens can be given to take their place. They can also help to treat abnormal bleeding from the uterus, PMS and in conjunction with HRT. They are probably best known for their use in birth control pills.

The Use Of Progestogens In HRT

Hormone Replacement Therapy (HRT) is recommended for women going through menopause or for those who have suffered damage to their ovaries. However, it is a controversial issue. The use of HRT implies that the fall in estrogen during menopause is a deficiency but menopause is a naturally occurring condition. It may actually be helping to protect the body.

For instance, it is known that estrogen can help the growth of certain breast cancers. Breast cancer is more prevalent in women around menopause age. So having a lower amount of estrogen in the bloodstream could be the body's own protection against breast cancer.

At one time, the media portrayed HRT as a necessary wonder-drug but evidence regarding its true benefits and safety is conflicting. However, many women have flourished on it.

HRT contains estrogen and if you have not had a hysterectomy (removal of the uterus) it will also contain progesterone. This is because estrogen supplements given on their own can trigger uterine cancer but if a progestogen is given with it, that risk is virtually eliminated.

Estrogen is able to lower the risk of heart disease by increasing HDL (a 'good' cholesterol) but synthetic progestogens seem to lower this benefit - with the exception of the new, micronized form.

Progesterone and PMS

Pre Menstrual Syndrome (PMS) can make life a misery. It is thought that PMS is caused either by a lack of progesterone, the actual drop of progesterone levels or by the fluctuating ratio of progesterone to estrogen.

Both natural and synthetic progesterones can be used in an effort to treat PMS. Natural progesterone is chemically processed from yams. It's given by suppositories (vaginal or rectal) or in the form of an injection. This is because it won't absorb if taken by mouth - so avoid any 'non-prescription' remedies containing extracts of wild or Mexican yam. It's physically impossible for them to work if swallowed.

Progestogens have been regularly prescribed for the treatment of PMS for the last 35 years. However, the British Medical Association still does not officially recommend them as the majority of studies have not found progesterone to have any meaningful affect. Nevertheless, many women claim that it has helped them.

Side Effects Of Progestogens

* Don't use if you have ever had blood clots in your legs or liver disease.

* Don't take in pregnancy unless continually monitored by a doctor.

* It may also cause bloating, tender breasts, weight gain, headache, moodiness and irregular vaginal bleeding.