1. Flo - ovulation calendar, period tracker, and pregnancy app
  2. F.A.Q.

How Does Flo Define Days Favorable for Conception?

favorable days for conception

If a woman can become pregnant only during ovulation, why is the fertile window much wider?

The app includes additional parameters to help you calculate your fertile window length.

For example, your ovulation is in 5 days and today you’ve had unprotected sex. Your egg could be fertilized, because sperm can survive for up to 5 days inside a woman’s body.

Usually, ovulation is hard to predict with 100% accuracy. (Only a doctor in the clinic can indicate it correctly with the help of an ultrasound.)

However, if you continuously input information about your cycles and symptoms into Flo, the app can give you an accurate fertile window. You can also track your basal body temperature.

The app makes predictions automatically and shows wide fertile window as trying to consider all the possible combinations.

Flo Period & Ovulation Tracker

4.8, 279.7K Ratings
  • Such an intuitive app! Hannah Malone
    I’ve tried several period tracker apps on the market and nothing is as good as Flo. It’s accurate, detailed providing you with an abundance of parameters to log, and they even provide useful articles and surveys to help you better understand the complex nature of the female body.
  • So accurate Connie Joseph
    I use this app to track my period and symptoms and it’s so accurate. I tried a few other apps before this one and they were never so accurate and didn’t have as many tools to use.

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