Fertility tracking for contraception
By tracking your menstrual cycle carefully, you can reduce the risk of pregnancy by avoiding unprotected sex during your most fertile days every month. On average, the 5-7 days leading up to and including the ovulation day are the most fertile, the days you are most likely to get pregnant.
Using Cycles to determine your most fertile days
You can determine when you’re most fertile every month by tracking physical symptoms, and using the days of your period to determine when you’ll ovulate next. A woman ovulates once per month, usually around day 14 in a 28 day cycle (day 1 being the first day of her period), and it is only during the days around her ovulation day that she can become pregnant.
Note: Fertility awareness does not protect you from contracting STIs and is never completely effective in preventing pregnancy.
However, when used together, the various fertility tracking methods can become more effective in determining your ‘fertile window’. Here are the three main fertility tracking methods:
The Temperature Method
This method requires that you take your basal body temperature to determine when you’re ovulating. Your body temperature rises slightly right after ovulation, so in order to anticipate this day for your next cycle, you should take your temperature right before bed and when you first wake up in the morning, everyday. Then, when you’ve determined what day of the month it is, you can plan to avoid unprotected sex during the 5-7 days leading up to and including your ovulation day (the fertile window).
The Cervical Mucus Method
Cervical mucus changes in consistency and color depending on if you are ovulating, when ovulation is very close and after ovulation has finished. Paying attention and taking notes on the consistency of cervical mucus can help you track when you’re most fertile. Here are some of the consistency types and what they mean.
- Not ovulating: Dry and sticky
- Ovulation is very close: Wet and watery
- Ovulation may be coming: Creamy
- Ovulation: Wet and stretchy, resembles egg whites
The Ovulation Test
The test measures your luteinising hormone levels (LH) and can be purchased in most pharmacies. To help determine when you are ovulating, start taking ovulation tests on day 11 of your cycle (11 days after the first day of your period) and continue until you notice the LH levels rise. When you notice your LH levels have risen, ovulation will typically occur 20-48 hours after, helping you determine whether you’re right about which day you ovulate every month.
How effective is fertility awareness?
When practiced properly, fertility awareness can be a quite effective contraception method and is the most effective when all tracking methods are practised at the same time. Although, the effectiveness can range depending on how well you track your period or the fertility awareness method you choose, but it is generally somewhere between 76-88% effective.
Note: your ovulation day can vary between cycles based on factors like stress, sickness, exercise and more. This is why no period tracker can say with 100% certainty when your ovulation will fall each month, and shouldn't be used a sole method of contraception.
That said, there are ways to get more accurate predictions in Cycles! If you consistently log your BBT, CMQ or ovulation tests, your fertility accuracy will improve.
- Download a menstrual cycle tracking app (ie. Cycles)!
- Track your symptoms throughout the month
- Calculate your cycle length
- Figure out your ovulation day and fertile window
- Avoid having unprotected sex during your most fertile days each month
This method is also beneficial if you eventually decide that you want to get pregnant, because you’ll already know when you should have sex every month if you want to conceive!