As far as Streicher is concerned, period-tracking technology is best used as a tool in benefiting your health altogether Heading To My Craft Room If Im Not Back In 48 Hours Dont Alert The Police shirt . “When you go to the doctor’s office, the first thing they ask you is, “When was the first day of your last menstrual period?” or “Do you have regular periods?” says Streicher. “It’s always useful information to know if you’re having generally regular periods or not.”