Cycle basics
Your fertility cycle starts on day one of your period (proper bleeding, not spotting) and lasts till the day before your next period starts.
Day one of your period is cycle day one. Count from this day to the day before your next period to get your cycle day and your cycle length. For example if your period starts on cycle day 29, your cycle length is 28 days.
It's easiest to use FAM as contraception if your cycles are between 21 and 35 days long, and don't vary by more than seven days.
It's easiest to use FAM as contraception if your cycles are between 21 and 35 days long, and don't vary by more than seven days.
How fertility changes during your cycle
The early days of your cycle are amber or relatively infertile. Your first fertile day is based on your cycle history.
Your fertile days are not a fixed event so you assume you are fertile for at least eleven days a cycle.
The infertile days at the end of your cycle are green because they are based on live data about your fertility indicators - usually waking temperature and fluid.
Your fertile days are not a fixed event so you assume you are fertile for at least eleven days a cycle.
The infertile days at the end of your cycle are green because they are based on live data about your fertility indicators - usually waking temperature and fluid.
When you start using FAM - and maybe for longer - you only have unprotected sex on your green days.