Everyone’s cycle is unique. It’s normal for even someone with very regular cycles to see a warning pop up occasionally. Lets look at what those warnings mean.

The Marquette NFP™ Pro app currently supports regular cycles only. In other words, a “regular cycle” in the Marquette Model is one that falls within this 21–42 day range. Postpartum or breastfeeding users need three complete cycles with lengths in this range to be considered regular.