Avoid Pregnancy

The Underlying Principle:

During an average cycle, there are around 6 days when a woman can conceive. By identifying and using protection (or abstaining) when you are fertile, you can effectively avoid pregnancy.

Why 6 days?

When we talk about fertility we are talking about the combined fertility of the couple.

A woman is only fertile for 12 to 24 hours per cycle (the lifespan of her egg), but sperm can live inside a woman’s body for up to 5 days, so the number of potentially fertile days jumps up to about 6 days (5 for the sperm plus 1 for the egg).

If you can learn when those fertile days are, you can avoid pregnancy naturally. Sign up below for our free educational series with step-by-step instructions delivered right to your inbox:

The 4 Rules

Below is an example of a chart from a woman using Kindara

ruLE #1

The First 3 Days Rule

You are generally considered infertile for the first 3 days of your period, as long as you had a temperature shift 12 to 16 days prior to it.

ruLE #2

The Dry Day Rule

You are generally considered infertile the evening of any day that you observed no cervical fluid. Once you start observing cervical fluid, you’re then considered fertile until you confirm ovulation with the two post-ovulatory rules.

ruLE #3

The Temp Plus 3 Rule

You are generally considered infertile the evening of the 3rd day after your temperature shift.

ruLE #4

The Peak Plus 4 Rule

You are generally considered infertile the evening of the 4th day after your most fertile CF, once your cervical fluid has become infertile again, and you have observed a clear temperature rise.

All Together

When all these rules are followed simultaneously, an ideal cycle would look like this

Note: Every woman is different. Make sure you know the rules, have charted for 3 cycles, and had your charts reviewed by an expert before you rely on Fertility Awareness as your sole method of avoiding pregnancy. If in doubt, always assume you're fertile.