Femometer is a women’s health brand operated by Lollitech. It offers fertility products including basal thermometers, ovulation tests and a smart ring. The Femometer Ring is worn overnight to make temperature tracking easier for people understanding their cycle or fertile window.

How it works
A sensor records temperature changes at the finger during sleep. The app looks for the sustained rise that often follows ovulation and combines it with cycle history and logged information. It estimates cycle phases, fertile days and period timing. Overnight sampling removes the need to take a manual basal temperature at the same time each morning.

Key considerations
Temperature can shift because of illness, alcohol, travel, poor sleep and room conditions. Ovulation is confirmed only after a rise has occurred, so predictions remain estimates.