Remember that finding out your risk category by analyzing your risk factors will only pick up about 70 percent of women at high risk. Having a bone scan is the most accurate way to access whether you are losing bone or not. If you feel you are at risk for bone loss, and are trying to decide about HRT, then a bone scan may aid you in your decision. If you are going to take HRT, there is no need for a bone scan.

A new screening method for osteoporosis is being tested. It involves an ultrasound of the heel, which would be a quick and inexpensive test. In addition, a urine test will soon be available from Ostex International of Seattle. This urine test will show whether a person is losing more bone than normal.

Women Who Don't Have Regular Periods At Risk For Bone Loss

Dr. Jerilynn Prior, a Vancouver endocrinologist and University of British Columbia researcher, says: "A woman who has a late onset of menarche [the first period] and intermittent ammenorrhea [no periods] and anovulation [failure to ovulate] is at risk for fracture by the time she reaches menopause." This risk can occur even if a woman is having regular periods but is not ovulating, and this happens more often as a woman moves toward menopause.

If you want to know whether you are ovulating, you can check your cervical mucous and basal temperature, and observe your symptoms (see chapter Know Your Body's Cycles). Dr. Prior has also made up specific charts for women to use in order to determine if they are ovulating, and has kindly allowed us to include them in this chapter.

Dr. Prior suggests that doctors ask: "Can you tell by the way you feel, that your period is coming?" Woman have probably ovulated if they answer that their breasts become tender along the sides, especially with fluid retention or bloating in the week before the flow. Women who notice only mood changes in the week before they menstruate are unlikely to have ovulated. If a woman says,"Sometimes I get breast tenderness and sometimes, I don't," then it is likely that the woman is ovulating off and on.

Dr. Prior corrects the problem by giving women Provera for ten days of the month until ovulatory cycles are re-established.

Estrogen And Progesterone - Which One Is Most Important For Bone Health ?

Dr. Prior believes that it is progesterone which is the important bone-saving hormone. Only a small number of doctors agree with her despite some compelling evidence.

Instead, doctors have been promoting estrogen as the most important hormone to reduce bone loss. In fact, estrogen hormone therapy has been widely used to prevent further bone loss in menopausal women and to reduce the incidence of fractures. Estrogen alone, in standard doses, does not appear to increase bone mass.

Once begun, estrogen therapy should be continued for at least eight to ten years, or longer. Stopping estrogen therapy, even after four years of treatment, may cause a rapid acceleration of bone loss.

However, some experts are now saying that bone health is still improved, even after estrogen is discontinued. British menopause experts, Dr. John Stevenson and Dr. Malcolm Whitehead, refer to studies which show that the effect of estrogen on bone is not lost after estrogen is stopped and that protection may persist into old age.

However, one study showed that 14 percent of women failed to improve their bone mass, even with adequate replacement of both estrogen and progesterone.

Many doctors now suggest that estrogen therapy be started at the onset of menopause. According to an editorial in the New England Journal of Medicine (Aug 27/92) by Dr. Riggs and Dr. Melton, from the Endocrinology Department at the Mayo Clinic: "If begun soon after menopause, estrogen therapy prevents the early phase of bone loss and decreases the incidence of subsequent osteoporosis related fractures."

However, there is no agreement among doctors as to how long hormones should be continued to prevent bone loss, although many doctors are now recommending taking HRT indefinitely.