Natural Family Planning: Fertility Awareness Method

Natural Family Planning, also called fertility awareness is a method of birth control that does not use any drugs or devices. It combines the calendar/rhythm method, the basal body temperature method, and the cervical mucus method. The natural family planning method is used both as a means of preventing pregnancy and as a way to target the most fertile time for getting pregnant.

How does natural family planning work?

The calendar, basal body temperature, and cervical mucus methods are combined to give you the awareness of when your body is most fertile.  As you become familiar with your body’s ovulation and fertile window, it provides you the opportunity to abstain from sexual intercourse or use a barrier method during that time.

How do you use fertility awareness?

The first objective within fertility awareness is to become familiar with your menstrual cycle and to begin charting your fertility pattern. The average menstrual cycle is between 28 to 32 days. 

Here is a glance at an average cycle to give you a gauge for examining your own cycle:

Day 1: The first day of your menstrual flow is the beginning of your cycle.

Day 7: By day seven your egg is preparing to be fertilized by sperm.

Days 11-21: (based on a 28-day cycle) Hormones in your body cause the egg to be released from the ovary, which is known as ovulation. The egg travels through the fallopian tube towards the uterus and is only available to be fertilized for 12-24 hours during this window. If the sperm penetrates the egg, the fertilized egg will attach to the lining of the uterus and begin to grow. If fertilization does not happen, the egg breaks apart.

Day 28: If the egg is not fertilized, hormone levels drop around this day, causing the lining of the uterus to be shed, which is known as menstruation.

It is important to realize that the first part of the menstrual cycle (before ovulation) is different in every woman and can even change from month to month. The number of days before ovulation can typically range from 13 to 20 days. The last half of the cycle is usually more similar for every woman because there are about 12-16 days from the day of ovulation until the start of the next period.

Calendar tracking method: Tracking your menstrual cycles may help you estimate your fertile times.

In order to track your menstrual cycle and identify your expected window of ovulation, follow the steps below:

Step 1: Plan on tracking your menstrual cycle for 8 to 12 months.

Step 2: Day 1 will be the first day you start menstruation.

Step 3: Pick the longest and shortest of the cycles from your monthly tracking.

Step 4: The first day of your fertility window is determined by subtracting 18 days from the length of your shortest cycle. If your shortest menstrual cycle was 26 days, subtract 18 from 26, which gives you the number 8. This means that the first day of your fertility window starts on the 8th day of your cycle.

Step 5: The last fertile day is determined by subtracting 11 from the length of your longest cycle. If 32 days was your longest menstrual cycle, take 32 and subtract 11, which give you 21. This means that the last day of your fertility period is on the 21st day of your cycle.

The time in between these are considered your fertility window. In the above example, your fertility window would be from the 8th day to the 21st day of your cycle. Your ovulation is expected to occur on one day during this time frame. You cannot get pregnant every day during this time, but it is during one 12-24 hour time frame during this window that pregnancy can occur.

If you are trying to avoid getting pregnant, you need to abstain from sexual intercourse or use a barrier form of birth control during your fertility window. If you are trying to get pregnant, this fertility window would be the targeted time for sexual intercourse.

Keep in mind that the calendar method and tracking of past cycles is only a guide.  Menstruation and ovulation can change from month to month.  However, by combining the calendar method with the other natural methods of tracking your ovulation described below, you can have a fairly accurate understanding of when you are ovulating.

Basal body temperature method: The basal body temperature method helps identify a change in temperature that occurs after ovulation and remains elevated until your next period. By looking at charting from a few cycles, your temperatures can reveal a pattern from which ovulation can be anticipated. The steps below can help you as you begin to track your temperature and identify when you are ovulating.

Step 1: Take your temperature orally each morning before you get out of bed.

Step 2: Use a basal thermometer, which recognizes small changes in your temperature. Your body temperature will only rise between 0.4 and 1 degree Fahrenheit when you ovulate.

Step 3: Record your temperature every day on your fertility tracking calendar.

If you record it every day, you will see that prior to ovulation your temperature is rather consistent. As you approach ovulation, you may notice a slight decline, but it will be followed by a sharp increase after ovulation. The increase in temperature is the sign that ovulation has just occurred.

Because the increase happens after you have ovulated, this method is best used by those who have time to track and study their charts for a couple of months, to ensure the best chances of conception. Illness, travel, and alcohol or drug use can affect your temperature and make it difficult to establish an accurate reading. Lack of sleep can also affect temperature reading, so it is important to get at least 3 consecutive hours of sleep before taking your basal body temperature.

Cervical mucus method: The consistency of your cervical mucus changes during the menstrual cycle. In the average cycle, after a 5-day menstrual flow, there are about 3 to 4 dry days.

The mucus wetness increases daily, lasting approximately 9 days until the wettest day. Your mucus is easily recognized at this point. It should be slippery, clear, stretchy, and look like egg whites. It can be difficult to conceive without this “egg white” cervical mucus, but there are natural products that can help improve mucus production if that is a concern.

Ovulation generally occurs within 1-2 days of your peak day of stretchy mucus. In order to use the cervical mucus method to identify your ovulation follow the steps noted below:

Step 1: Collect the mucus from the vaginal opening with your fingers by wiping them from front to back.

Step 2: Record it daily on your fertility calendar by making note of the color (yellow, white, clear, or cloudy), the consistency (thick, sticky, or stretchy) and the feel (dry, sticky, lotion-like, wet, slippery, or stretchy).

Step 3: Ovulation usually occurs within 1-2 days of when your mucus is clearest, slippery, and most stretchy, if not on the peak day itself.
When using the fertility awareness method, do not douche or use spermicides, which increase your risk for infection and may wash away or change the appearance of the mucus.

How effective is fertility awareness?

When fertility awareness is used correctly and consistently, it may reach rates of effectiveness around 90%. The effectiveness depends on your diligence to track and record your fertility pattern and your commitment to abstain from sexual intercourse or use a barrier form of birth control during your fertility window.

Average use shows a failure rate of approximately 25%. If you are committed to tracking and recording your fertility information, you can achieve much higher success rates.

What are the side effects or health risks of fertility awareness?

There are no health risks or side effects associated with fertility awareness.

Is it reversible?

Yes. Fertility awareness does not have any effects on the male or female reproductive functioning. Pregnancy is possible immediately following the practice of fertility awareness.

How much does it cost?

Fertility awareness is free to inexpensive. Free training sessions are usually available around your community through health centers, pregnancy services, or some churches.

Thermometers used to measure basal body temperatures cost between $10 and $15 and are available at local drugstores, grocery stores, or supercenters. You may use one of your home calendars to record this information, or you can purchase a fertility awareness chart which cost approximately $8. You can also find free charts online to print.

What about fertility awareness and sexually transmitted diseases (STDs)?

Fertility awareness does NOT provide any protection against sexually transmitted diseases.

Are there any other physical signs of ovulation?

Your fertility window may be identified by paying attention to other functions of your body.
Secondary signs of ovulation may include:

  • Changes in the cervix (The cervix will become high, soft, and open.)
  • Slight one-sided pain in the area of an ovary
  • Breast tenderness

Keep in mind that these secondary symptoms should not be relied on exclusively if using FAM as birth control. Always make sure to back them up by checking the primary symptoms (cervical mucus and basal temperature).

What are the pros and cons of fertility awareness?

The pros include:

  • Effective when used correctly and consistently
  • No side effects
  • Immediate reversibility
  • Inexpensive or free
  • No devices, drugs, prescriptions, or office visits
  • Does not contain estrogen, which may increase the risk of heart problems
  • Acceptable for couples who have religious concerns related to contraception
  • Effective for couples who are preventing or trying to get pregnant

The cons include:

  • Requires diligence from both partners
  • Requires periods of abstinence or backup contraception for approximately 1/3 of the month
  • Requires consistent and accurate record-keeping
  • More challenging for women with irregular cycles

Use and/or print an ovulation calculator to better understand your menstrual cycle and ovulation.

Our Ultimate Fertility Resource Guide provides the information you need on fertility, tips on how to get pregnant faster, and how to boost fertility through sometimes simple tweaks to your lifestyle and approach. The guide is easy to read and meant for anybody wanting to increase their ability to conceive. It’s a free download and includes coupon codes for essential products. Even free Nightfood Nighttime Ice Cream.

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Compiled using information from the following sources:

1. Weschler, T. (2002). Taking charge of your fertility (Rev. ed.). New York, NY: HarperCollins Publishers Inc.