Natural family planning charts are helpful tools to both the woman seeking a form of contraception and the one hoping to get pregnant. They all help women find their most fertile days in each menstrual cycle.
There are hundreds of products on the market sold as natural family planning charts. Some are available only through family planning classes, however.
While some charts record only one way to measure fertility – such as basal body temperature – others record multiple types of readings and can be quite complex. For the woman who wants to avoid pregnancy, understanding all aspects of the chart before using it is essential. Examples of some of the more popular charts and instructions for using them can be found at the Georgetown University Institute for Reproductive Health site.
According to WebMD, all the methods of natural family planning captured on charts are based on finding the time of ovulation. For optimal planning effectiveness, women should use all the methods in combination for several months before attempting to use them as natural birth control.
The charts by themselves are relatively inexpensive. However, the cost of natural family planning classes varies greatly. Women can use charts to track the following methods of planning:
A woman needs to guess her next ovulation event after recording several months of menstrual cycles, which is fairly easy to learn. Based on the chart, she deduces on which days of the month she’s most likely to ovulate. Fertile days begin five days prior to ovulation.
The main disadvantage is that this type of chart only works if she has regular 28-day menstrual cycles. Even women with regular cycles occasionally experience irregular ones. Women don’t always ovulate exactly in mid-cycle. Some experts advise that it’s more likely to happy between 9 and 17 days prior to her next period. This makes this type of tracking imprecise when used alone.
Standard Days Method (SDM)
This type of charting utilizes a string of colored beads known as CycleBeads to track a woman’s cycle. It works best for those with cycles between 26 and 32 days long.
To use this type of tracking, the red bead counts as day 1 of a woman’s period. Each successive day is one bead. A dark brown bead corresponds to day 26. The last brown bead before the red bead represents day 32.
Unfortunately, women who have more than one cycle a year shorter than 26 days or longer than 32 probably will need to use another type of charting to avoid becoming pregnant.
Basal Body Temperature (BBT)
A BBT chart tracks a woman’s lowest body temperature during the day taken with a special thermometer. Changing hormone levels cause her BBT to fall a day or two prior to ovulation, then rise one to two days after she ovulates. By carefully measuring and charting the BBT every morning, it’s possible to deduce the day when ovulation will occur.
The disadvantage of charting basal body temperature is that when charted by itself, it can be inaccurate since the temperature difference is often less than 1 degree F.
Cervical Mucus (Billings)
The Billings method of charting requires a woman to record the look, texture and amount of cervical mucus as it changes during her menstrual cycle. Immediately after a period, the amount of mucus is slight, with a thick, cloudy and sticky appearance. Right before and during ovulation, it looks clear and appears thin and stringy.
Charting the changes gives a woman an idea of when ovulation occurs. However, when charting only cervical mucus, the woman is somewhat reduced to guesstimating when she can become pregnant or the times she should avoid if she doesn’t want to conceive. In addition, many women find the process of collecting and examining cervical mucus messy and objectionable.
Home ovulation kits on the market check the level of luteinizing hormone (LH) in a woman’s urine. She inserts a dipstick into her urine, then reads the level on the strip or inserts the strip into a small computer unit. The result indicates her most fertile days.
Some women prefer to use a combined chart on which they enter the results in addition to data from any other natural family planning methods utilized. The main drawback to this type of charting is the cost of the kit.
Considered by some to be the most accurate method of charting, it combines the results of several methods to help pinpoint the most fertile days of a cycle. It involves entering data on basal body temperature, changes in cervical mucus, hormone testing and physical changes like breast tenderness and mood changes.
The disadvantage to this type of chart is the sheer complexity and time required to record all the data required.
Georgetown University Institute for Reproductive Health site