Validity of the Bioself 110 fertility indicator

The Bioself 110 (Bioself Canada, Inc., Montréal, Québec, Canada) is an electronic computerized thermometer designed to identify the fertile and infertile phases of the menstrual cycle. The purpose of this study was to evaluate the validity of the device by comparing it with a reference method, the Ovustick (Monoclonal Antibodies, Inc., Mountain View, CA) luteinizing hormone (LH) surge detection kit. The Bioself 110 identified the 6-day fertile period in 86.4% of 220 cycles studied and 5 fertile days in 93.2%. The Bioself 110 correctly identified the postovulatory infertile phase in 93.3% of 178 cycles. On average, the device identified 10.9 fertile days and 10.6 postovulatory “safe” days per cycle. It was concluded the device would be a useful aid to couples trying to conceive or prevent pregnancy.