Natural family planning is sometimes used to plan the size of a family without using contraceptives. The method is based on predicting the day in the menstrual cycle when ovulation takes place. Intercourse for that day and the following week carries a high risk of conception.
There are several ways to calculate the time of ovulation. The basal body temperature method requires taking your temperature with a special thermometer every morning before getting out of bed. On the day of ovulation, your temperature will rise slightly and will remain elevated until you begin your next period. To avoid conception, abstain from intercourse during the first three full days after the temperature rise.
The cervical mucus method is another alternative. When using this method, look for changes in your cervical mucus throughout the first part of your menstrual cycle. Before ovulation mucus is cloudy and thicker in consistency. A few days before ovulation, the mucus becomes clear and slippery. Avoid intercourse from the time the clear mucus appears until four days after it becomes cloudy and thicker.
The calendar or rhythm method requires charting your menstrual cycles on a calendar to predict ovulation. For this method to be effective, however, you must have regular periods. The calendar or rhythm method is the least effective of the natural family planning methods. Use a combination of all three methods for the best results.
You can learn more about this topic by visiting The American College of Obstetricians and Gynecologists website.