My menstrual cycles began speeding up since I turned 40. My doctor told me that women's cycles sometimes quicken as menopause approaches. I only have 8 to 12 days between cycles now (instead of 21). Is this much acceleration normal? Can you recommend good books on menopause? Thanks.

--Louise

Although the "classic" pattern for women approaching menopause is for cycles to get farther apart, anything can -- and does -- happen, including shorter cycles. The change in cycle length happens because ovulation no longer occurs every month; thus, subtle changes in hormone levels and hormone balance occur, throwing the delicate balance off. As estrogen begins to decline, other symptoms may appear such as hot flashes, night sweats, emotional lability (the "cry at the drop of a hat" feeling), and short-term memory loss. Every woman experiences this transition in her own way.

Normally, we count cycle length as the time from the beginning of one period to the beginning of the next. I'm assuming when you say you only have 8 to 12 days between cycles, you mean from the end of one to the beginning of the other. If I go ahead and make a further assumption that your periods last 5 days, then you are having 13- to 17-day cycles. This is not normal, and while it may be no more than your body's way of reacting to the hormonal changes of the perimenopause (the time before menopause), it should be investigated. I would recommend a blood count to rule out anemia, a thyroid test, a complete physical exam by your doctor, and an evaluation of the uterine lining.

As for recommended reading, the American College of Obstetricians and Gynecologists offers an excellent pamphlet: "The Menopause Years." You should be able to get it from your gynecologist.