How It Is Done
For fertility awareness to work well, it is best to use all of the following methods together.
Calendar (rhythm) method
Record the dates of your menstrual periods for 6 to 8 months. See if your menstrual cycle is regular and how many days it is. If your cycle is regular and about 28 days long, you are most likely to ovulate 14 to 15 days after menstrual bleeding begins.
To find the first day that you are likely to be fertile, take 18 away (subtract) from the number of days in your shortest menstrual cycle. Your first fertile day should be that many days after your menstrual bleeding begins. For example, if your shortest menstrual cycle is 26 days long, you would subtract 18 from 26 to get 8; your first fertile day would then be the 8th day after menstrual bleeding begins.
To find the last day that you are likely to be fertile, subtract 11 from the number of days in your longest menstrual cycle. Your last fertile day should be that many days after your menstrual bleeding begins. For example, if your longest menstrual cycle lasts 31 days, you would subtract 11 from 31 to get 20; your last fertile day would then be the 20th day after menstrual bleeding begins.
Sperm can live in your vagina 3 to 5 days after sex.
- If you want to become pregnant, have sex every day or every other day from your first fertile day to your last fertile day.
- If you do not want to become pregnant, do not have sex or be sure to use another method of birth control for 1 week before your first fertile day. In the example above, your fertile period is from day 8 to day 20, so protect yourself from becoming pregnant for these 12 days of your cycle.
The calendar method of birth control is not the best choice for women who have short, long, or irregular menstrual cycles. For this reason, the calendar method alone is never recommended for birth control. It must be used in combination with other birth control methods.
Standard days method (SDM)
On the first day of your period, move the ring to the red bead (day 1) on the CycleBeads. Count each day as one bead. On days 1 to 7, you can have unprotected sex. On days 8 to 19, do not have sex or be sure to use another method of birth control to avoid pregnancy. From day 20 to the end of your cycle, you can have unprotected sex. All brown beads are days when you are not likely to become pregnant. All white beads are days you are likely to become pregnant. The dark brown bead marks day 26 and the last brown bead before the red bead is day 32. The SDM works best for women who have cycles between 26 and 32 days long.
Basal body temperature (BBT) method
Take your temperature every morning for several months just after you wake up. Do it before eating, drinking, or doing any other activity. Use a special ovulation thermometer or digital thermometer that shows tenths (0.1) of a degree. Your temperature may be taken orally or rectally, but be sure to use the same location and the same thermometer each time. Leave the thermometer in place for a full 5 minutes. Record your temperature, then clean the thermometer and put it away. Any activity can change your basal temperature. Record your temperature on a chart or graph. Use a simple Fahrenheit temperature chart (What is a Reference PDF Opens New Window document?) or Celsius temperature chart (What is a Reference PDF Opens New Window document?) to track your temperature. Ovulation usually causes your BBT to rise by 0.4°F (0.2°C) and to stay high for over a week.
If you want to become pregnant, have sex every day or every other day from your first fertile day until 3 days after your BBT rises.
If you do not want to become pregnant, do not have sex or be sure to use another method of birth control from the end of your menstrual period until 3 days after ovulation. After your temperature rises and stays high for 3 full days, your fertile days will be over. Your temperature on these 3 days should stay higher than on any of the other days in that cycle.
Cervical mucus method (Billings method)
Each day, put one finger into your Reference vagina Opens New Window and record the amount, color, and thickness (or thinness) of the mucus. Test the "stretchiness" of the mucus by putting a drop of it between your finger and thumb. Spread your finger and thumb apart and see if the mucus stretches.
After your period, you will not have much cervical mucus and it is thick, cloudy, and sticky. Just before and during ovulation, you will have more cervical mucus and it is thin, clear, and stringy. It may stretch about 1 in. (2.5 cm) before it breaks.
If you want to become pregnant, have sex every day or every other day from the day you see your cervical mucus becoming clear and stretchable until the day it becomes cloudy and sticky. Do not test your mucus right after sex since semen may be mixed with it.
If you do not want to become pregnant, do not have sex or be sure to use another method of birth control from the day your cervical mucus becomes clear and stretchy until the 4th day after it becomes cloudy and sticky.
Another 2-day method of checking your cervical secretions can be done. Every day of your cycle, ask yourself if you have secretions today and did you have secretions yesterday. For all days that you answer "yes" to one of these questions, it is likely that you are fertile and can become pregnant if you have unprotected sex. If you answer "no" to both questions on any day, you are not likely to become pregnant.
If you are using a home ovulation kit, follow the instructions on the kit exactly.
Combined (symptothermal) method
This method uses some of the other methods all at once to tell you the most fertile days of your cycle. You check your basal body temperature, the changes in your cervical mucus, a hormone test, and watch for signs of ovulation (such as breast tenderness, abdominal pain, and mood changes). You may have any of the following physical signs of ovulation:
- Breast pain
- An increase in sexual desire
- Pain in your lower belly on one side or the other (called mittelschmerz). This pain can be sharp or dull and usually lasts from a few minutes to a few hours. It occurs when the egg is released from the Reference ovary Opens New Window on that side. The ovaries usually switch releasing an egg each cycle, so pain occurs on the side the egg is released from during that cycle.
If you do not want to become pregnant, do not have sex or be sure to use another method of birth control for 5 days before ovulation may occur and on the day of ovulation.
|By:||Reference Healthwise Staff||Last Revised: Reference December 7, 2011|
|Medical Review:||Reference Sarah Marshall, MD - Family Medicine
Reference Femi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology