Investigators at the Center for Disease Control know so little thus far about why tampons increase a woman's risk of toxic-shock syndrome that their recommendations to the public are few and simple.

The investigators' overall message is that tampons carry some risk, and should be used with care.

The recommendations are:

All tampons, except for Rely, appear to increase risk equally. No other brand has been proved more or less dangerous than the rest.

If a woman wants to virtually eliminate risk of the rare but dangerous disease, she can stop using tampons. Using tampons during only part of her period (that is, removing them at night or sometimes using pads) will lower risk.

There is no evidence that using smaller or less absorbent tampons or changing them more often will protect her.

Any woman who develops a high fever, vomiting or diarrhea during her menstrual period should stop using tampons and consult her doctor.

Doctors who suspect a patient has toxic-shock syndrome should culture her vagina and cervix, remove any tampons fragments, monitor blood pressure and give antibiotics active against staph bacteria. Antibiotics appear not to speed recovery, but do seem to prevent the disease from recurring during subsequent periods. For this reason, women who have had toxic-shock syndrome should have bacterial cultures, receive antibiotics if staph are found, and not use tampons at least for several months.