A rather lengthy article from the Washington Post on “CycleBeads,” developed at Georgetown as a means for women to track their menstrual cycles and chart, after a fashion, fertile and infertile days.

The necklace is a tool that helps a woman track her menstrual cycle: Slide the little black gasket onto the fat part of the red bead on the first day of a period. Then advance that gasket across the brown beads, at the rate of one a day. When the gasket reaches the 12 white beads, pregnancy is likely if a woman has unprotected sex. (This danger zone is easy to confirm in the darkness of the bedroom, since the white beads glow in the dark.) After the gasket slides past the white beads, it resumes its march across brown beads, and pregnancy is unlikely once more.

According to two studies in the peer-reviewed journal Contraception — one published this year and one two years earlier — the method, used correctly, is more effective than a diaphragm and nearly as effective as a condom. This summer, the Standard Days Method and CycleBeads will be inducted into the bible of contraception, “Contraceptive Technology.” Being included in the latest update of this family planning reference book used by health care professionals could feed demand for CycleBeads, which retail for $12.95, and never require a refill. In the 13 months since they became available, 30,000 women have started to use this method, according to the IRH. CycleTechnologies, the New York-based company that’s manufacturing CycleBeads, projects that figure will double by the end of 2005.