How to Use the Fertility Awareness Method

A woman’s menstrual cycle is divided into three phases:

1. the pre-ovulatory infertile phase
2. the fertile phase
3. the post-ovulatory infertile phase

The Fertility Awareness Method (FAM) can help you accurately determine when your fertile phase (Phase 2) starts and ends. This, in turn, can help you avoid getting pregnant.

Fertility Signs

This scientifically validated natural birth control method involves observing and charting three fertility signs: your waking temperature, the consistency of your cervical fluid (or mucus) and the position of your cervix. This webpage provides an overview of what’s involved. To use the FAM properly, it is important that you fully understand the FAM guidelines and apply them consistently. To learn the ins and outs about using FAM, you can read a book, such as Taking Charge of Your Fertility: The Definitive Guide to Natural Birth Control, Pregnancy Achievement, and Reproductive Health, by Toni Weschler, or you can take a course with a certified FAM practitioner.

Although it takes some time to learn the method, once learned, you will find that it takes only a few minutes each day.

A basal thermometer allows a woman to take her waking temperature.

Waking Temperature
Your waking temperature is your body temperature when you first wake up in the morning. A woman’s waking temperature fluctuates from day to day but typically ranges from about 36.1 to 36.4 degrees Celsius (97.0 to 97.5 degrees Fahrenheit) before ovulation. A woman's temperature usually rises rapidly following ovulation, to between 36.4 and 37.0 degrees Celsius (97.6 and 98.6 degrees Fahrenheit). It usually remains in this higher range during the 12 to 16 days until your next period.

Monitoring your waking temperature using a basal thermometer can help you determine when you have ovulated. You can purchase a basal thermometer from a drugstore. You should take your temperature first thing in the morning, after at least three hours of sleep, before you get up or do anything. Basal thermometers show increments of 1/10 of a degree.

Charts for tracking your waking temperature are available online, free of charge. Click here to download and print a chart.

Cervical Fluid
The fluid produced by a woman's cervix changes over the course of her menstrual cycle. After menstruating, there is usually no fluid for a few days. The cervical fluid may then become sticky, and then creamy. As ovulation approaches, the fluid becomes wetter and wetter. During your most fertile days, it becomes clear and slippery and can be stretched between your fingers, like raw egg white, to allow easy movement for sperm. On ‘safe,’ or infertile, days, there is either no fluid or less fluid that is noticeably thicker.

By checking the consistency of your cervical fluid every day from the time your period ends until after you ovulate, you can help predict your ‘safe’ and 'unsafe' days.

Position of the Cervix
Monitoring the position of your cervix can help corroborate your other two body signs (your waking temperature and cervical fluid). During your infertile periods, the cervix is low, hard and closed. As your fertility increases, your cervix rises, softens and opens.

The Fertility Cycle

Phase 1 of your cycle starts on the first day of your period. During this phase, your body basal temperature stays within a low range and there is no cervical fluid. Phase 1 is generally considered infertile although your fertility increases towards the end of it.

Phase 2 starts with the appearance of any cervical fluid. The colour and consistency of the fluid changes as you approach ovulation. The most fertile type of fluid resembles raw egg white. Towards the end of this phase, after you have ovulated, your basal body temperature rises. If you want to avoid getting pregnant, do not have unprotected sex during Phase 2. Phase 2 typically adds up to about nine or 10 days, during which you should abstain from having sex or use a barrier method of birth control. This fertile phase includes a safety margin on both sides of your fertile days.

Phase 3 begins at least three days after there has been a significant shift upward (thermal shift) in your waking temperature, which has stayed higher than the previous six days for at least three consecutive days. During this infertile phase, your cervical fluid dries up and your waking temperature stays within the higher range. During this phase, you can have unprotected sex until your next period.

While you may find that the length of Phases 1 and 2 vary from one cycle to the next, the length of your Phase 3 is likely consistent from cycle to cycle, give or take a day or two. This is because the length of time between ovulation and menstruation is very consistent – almost always 12 to 16 days.

Lactation Amenorrhea

This is the medical term for the period of time after giving birth when you are breast-feeding and your period has not begun. Having sex during this time is 98 percent 'safe' if:

• you gave birth in the last six months;
• your period has not returned;
• your baby is breastfeeding; and
• this is the only way your baby is eating and you are breastfeeding at least every four hours during the day and every six hours at night (you should never go more than six hours between feedings at night).

Note: Using a breast pump does not have the same effect as breastfeeding.

Ovulation Predictor Kits

These kits test a woman's urine. They measure hormone levels and predict when ovulation will occur. These methods only turn positive 12 to 48 hours before ovulation; they do not indicate the start of your unsafe time. They can, however, be used to help chart your ovulation pattern. They are also helpful for women who want to identify the best times to try and get pregnant.

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