on the Symptothermal Method
This on-line document explains how a woman can
learn to identify her fertility signs and symptoms.
Women wishing to use the Symptothermal Method
to avoid or to achieve a pregnancy are advised
to contact a qualified Natural Family Planning
The Symptothermal Method consists of observing more
than one indicator of the woman’s fertility. Most
couples who use a combined or symptothermal approach
use cervical secretions and Basal Body Temperature to
identify the fertile time. Some women also check the
position and feel of their cervix or use a calendar
calculation as a “double-check” against
cervical secretions to identify the start and end of
the fertile time. Other minor indicators include noting
ovulatory pain (mittelschmerz) or breast tenderness.
Ovulatory pain refers to lower abdominal pain or cramping
some women feel around the time of ovulation.
Basal Body Temperature (BBT)
The BBT is the body temperature of a healthy person
on awakening. The BBT rises under the influence of progesterone.
Most ovulatory cycles demonstrate a biphasic BBT pattern:
lower in the first part of the cycle, rising to a higher
level beginning around the time of ovulation, and remaining
at the higher level for the rest of the cycle. By taking
her temperature on a chart each day of her menstrual
cycle, a woman can retrospectively identify when she
may have ovulated. However, because the BBT does not
give adequate advance warning of ovulation, it cannot
be used to identify the start of the fertile time. Therefore,
it is of limited use for a woman who wants to achieve
Figure 1. Temperature variations during
a menstrual cycle
Figure 1 (above) illustrates
the BBT variations during a model menstrual cycle of
28 days. In reality, the BBT may rise more suddenly
or more gradually. The typical pattern of a lower temperature
before ovulation, followed by a higher temperature immediately
before, during, and after ovulation, can be disrupted
by illness, stress, travel, or interrupted sleep.
Use the BBT to determine the postovulatory infertile
- Take your BBT every morning at the same time before
getting out of bed (after at least 3 hours of sleep).
A special calibrated thermometer makes temperature
reading easier. Take the BBT orally, rectally, or
vaginally, but take it at the same site each day so
changes in BBT can be detected accurately.
- Record your BBT readings daily on a special
NFP chart (similar to that in Figure
4). Connect the dots for each day so a line connects
dots from day 2 to day 3, and so on.
- Your temperature will probably rise at least 0.4°
F around the time of ovulation and remain elevated
until the next menses begins. Your actual temperature
and maximum temperature are not important, just the
rise over the baseline (preovulatory) temperatures.
- If you have 3 days of continuous temperature rise
following 6 lower temperatures, you have ovulated
and your postovulatory infertile time has begun. To
see the baseline and rise clearly on the chart, draw
a line just above (0.1 degree line) the lower (preovulatory)
temperatures. When you record 3 continuous temperatures
above this line and the last temperature is 0.4 degrees
higher than this line, your postovulatory infertile
time has begun.
- If you cannot detect a sustained rise in BBT, you
may not have ovulated in that cycle. A true postovulatory
BBT rise usually persists 10 days or longer.
- Some woman notice a temperature drop about 12 to
24 hours before it begins to rise after ovulation,
whereas others have no drop in temperature at all.
A drop in your BBT probably means ovulation will occur
the next day.
- To conceive. It is not possible
to predict fertile days using BBT. By the time the
rise is detected, you are probably in the infertile
phase of your menstrual cycle and have missed the
opportunity to become pregnant. A biphasic temperature
pattern, however, can let you know you are probably
- To avoid pregnancy. Because the
ovulation may occur as early as day 7 of the menstrual
cycle, assume you may be fertile from just after menses
(if your cycles are no less than 25 days in length)
until your temperature has remained elevated for at
least 3 consecutive days. The most effective way to
use BBT charting when avoiding pregnancy is to avoid
intercourse all through the first part of your cycle,until
the temperature rise indicates you have ovulated.
Note: Because BBT does not provide information
about the beginning of the fertile time, it is rarely
used as the only fertility indicator by a woman who
is using NFP.
Changes in cervical secretion signal the beginning
and end of the fertile time, even among those who have
irregular cycles. Observe your cervical secretions by
“the look, touch, and the feel”:
- Look at the secretions on your undergarments, fingers,
or toilet paper to determine its color and consistency.
- Touch the secretions to determine their stretch
- Feel how wet the sensation is at your vulva when
you are walking.
When they first appear, the secretions may be scant
but sticky and thick with a cloudy color. Highly fertile
secretions are clear, stretchy, wet, and slippery. Ovulation
most likely occurs within 1 day before, during, or 1
day after the last day of clear, stretchy, slippery
cervical secretions. When you are observing your cervical
secretions, do not douche, because it can wash out the
secretions, making it very difficult to notice changes.
Figure 2. Cervical secretion variations
during a menstrual cycle.
Use your cervical secretions to identify
the beginning and end of the fertile time:
- 1Observe your cervical secretions every day, beginning
the day after your menstrual bleeding has stopped,
and record them daily on a special chart (see
Figure 2). To help you avoid confusing cervical
secretions with semen and normal sexual lubrication,
some counselors advise complete sexual abstinence
throughout the first cycle.
- Check secretions each time before and after you
urinate by wiping (front to back) with tissue paper.
Note and record the color and appearance (clear, or
cloudy) and consistency (thick, sticky, or stretchy)
of the secretions, and how they feel (dry, wet, or
slippery). Record how much they stretch when pulled
between your thumb and index finger. Also, note and
chart the sensations of dryness, or wetness at your
vulva. Always record the “most fertile”
observations you see during the day.
- Note the typical pattern in the cervical secretions:
- During menstruation, blood masks any other
sensations of wetness or secretions.
- After the menstruation, the vagina may feel
moist a few days, but not distinctly wet. There
usually are no observable secretions. (Some women
do not have any of these dry days, especially
if they have very short cycles.)
- Next may come secretions that are thick and
sticky, cloudy. The vagina still does not feel
distinctly wet. This can last for several days.
Consider these days as fertile.
- As ovulation nears, your secretions usually
become more abundant, and you will have an increasingly
wet sensation. Secretions become clear and slippery
and can stretch 2 to 3 or more inches between
the thumb and forefinger. The peak or last day
of wetness or clear, slippery secretions is assumed
to be about the time of ovulation.
- After ovulation, the secretions become thick,
cloudy, and sticky or disappear until the time
of the next menstrual period.
- Douching, vaginal infection, semen, foam, diaphragm
jelly, lubricants, medications, and even the normal
lubrication of sexual arousal may interfere with the
ability to notice a clear-cut secretion pattern.
To conceive. Have intercourse when
cervical secretions are present. The probability of
conception is greatest when the secretions are clear,
stretchy, and slippery.
To avoid pregnancy. Check for secretions
as soon as your menses are complete. (Some counselors
recommend avoiding intercourse during menses because
it is difficult to detect secretions when they are mixed
with menstrual blood.) You can have sexual intercourse
on preovulatory days if no secretions are present. (Some
counselors recommend abstaining the next day and night
following intercourse to allow time for bodily fluids
to drain out of your body so you will not confuse semen
and arousal fluids with cervical secretions. The following
day, check your cervical secretions.) The fertile time
begins when cervical secretions are first observed until
4 days past the peak day (the last day of clear, stretchy,
See Figure 3 (below) for an example
of a chart completed by a woman using BBT, cervical
secretions, cervical position and feel, and other minor
Figure 3. Symptothermal variations
during a model menstrual cycle
chart and a sample
completed chart may be downloaded here.
Instructions for using the chart are available on the
Planning Chart and Information Page.
Fertility Awareness: Beyond Family Planning
Learning about their fertility is important
for men and women, regardless of which family planning
method they use or whether they choose to use family
planning at all. Information about their fertility and
the skills to apply this information to oneself is called
“fertility awareness”. Fertility awareness
increases peoples’ knowledge of their reproductive
potential and enhances self-reliance. Some couples like
the active involvement required of the male partner,
who learns about his own and the woman’s fertility
and then abstains from intercourse when the woman is
fertile. Fertility awareness information can be used
for a number of purposes:
To conceive. Couples
have intercourse on days the woman is potentially fertile.
These include the days she observes cervical secretions
or notes that her cervix is relatively soft and open.
The chances of achieving a pregnancy are greatest when
the woman observes clear, stretchy, slippery secretions.
Conception is most likely to occur within 1 or 2 days
of peak mucus (secretions).
To detect pregnancy.
A postovulatory temperature rise (see the section on
“Basal Body Temperature Charting”) sustained
for 18 or more days is an excellent early indicator
that pregnancy is under way.
To avoid pregnancy. For
maximum effectiveness, couples should abstain from intercourse
during the entire fertile time as indicated by the NFP
To detect impaired fertility.
Charting fertility signs costs relatively little and
can aid in diagnosing and treating fertility problems
due to infrequent or absent ovulation. Women who do
not ovulate tend to have a meandering BBT pattern throughout
the cycle, rather than the typical biphasic pattern
(lower in the first part and higher in the second).
To detect a need for medical attention.
Changes in cervical secretions, abdominal pain, and
other signs may indicate the need for medical attention.