Natural family planning (NFP) is a form of birth control that does not involve pills, devices, or hormones. Instead, it relies on tracking your body’s natural signs of fertility to determine when you are most likely to get pregnant or avoid pregnancy. NFP can be used for both purposes, depending on your goals and preferences.

NFP can be up to 99% effective if followed consistently and correctly, but it requires careful observation, recording, and interpretation of your fertility signals. It also requires abstinence or using another method of contraception during your fertile days if you want to prevent pregnancy. NFP does not protect against sexually transmitted infections (STIs), so you may need to use condoms as well.

There are three main fertility signals that you can monitor and record for NFP: the length of your menstrual cycle, your basal body temperature (BBT), and your cervical mucus. You can use one or more of these methods to identify your fertile window, which is the time when you are most likely to conceive.

• The length of your menstrual cycle: Your menstrual cycle lasts from the first day of your period until the day before your next period starts. This can vary from 21 to 40 days, depending on the person. Ovulation, which is when an egg is released from one of your ovaries, usually occurs 10 to 16 days before your next period. You can use a calendar or an app to track the length of your cycles and estimate when you are likely to ovulate.
• Your basal body temperature (BBT): Your BBT is your lowest body temperature in a 24-hour period, which you measure first thing in the morning before you get out of bed or do anything else. Your BBT can rise slightly (0.5 to 1 degree Fahrenheit) after ovulation and stay elevated until your next period. By taking your temperature every day and charting it on a graph, you can see when this rise occurs and confirm that you have ovulated.
• Your cervical mucus: Your cervical mucus is the fluid that comes out of your cervix, the lower part of your uterus. It changes in color, texture, and amount throughout your cycle, depending on your hormone levels. When you are ovulating, your mucus is clear, stretchy, and wet, like raw egg whites. This type of mucus helps sperm swim and survive in your reproductive tract. By checking your mucus every day and noting its characteristics, you can tell when you are most fertile.

Once you have learned how to track your fertility signals, you can use them to plan or avoid pregnancy. There are different methods of NFP that use different combinations of these signals, such as:

• The rhythm method: This is one of the oldest and simplest ways of NFP, but also one of the least reliable. It is based on counting the days of your cycle and avoiding sex on the days when you are most likely to ovulate. However, this method does not account for variations in your cycle length or other factors that can affect your fertility.
• The cervical mucus or ovulation method: This method focuses on observing and recording your cervical mucus changes throughout your cycle. You avoid sex or use another method of contraception on the days when your mucus is clear, stretchy, and wet, indicating high fertility.
• The basal body temperature (BBT) method: This method involves measuring and charting your BBT every morning. You avoid sex or use another method of contraception until you have seen a sustained rise in your temperature for at least three days, indicating that ovulation has occurred and that you are no longer fertile.
• The symptothermal method: This method combines two or more fertility signals, such as BBT and cervical mucus, to give you a more accurate picture of when you are ovulating and when you are safe to have sex without risking pregnancy.

Whichever method you choose, you need to follow the