The Natural Family Planning Page
Natural Family Planning (NFP) refers to several methods for
spacing, postponing, avoiding or enhancing the possibilities of conception, without
any chemical or physiological alterations of the reproductive system (female or male).
Contemporary methods, which are the focus of this page, are sometimes referred
to as 'Fertility Awareness' since they are ultimately based on awareness of natural
symptoms of fertility that are readily recognizable by any woman. As such they are
distinct from older 'calendar' methods such as Ogino-Knaus (the so-called 'rhythm').
NFP has extensive support in the medical literature since the 'seminal' article
appeared in the 'Lancet' in 1972. A select bibliography will eventually be available
here. Meantime much of it can be found by consulting the Billings, Nature's Method
and CCL sites. Good sources for NFP bibliography are recommended in this note from
Dr Joe Stanford of the University of Utah.
NFP methods in brief:
The Billings Ovulation Method of NFP
It is a method of family planning which takes advantage of the biological fact
that women are infertile more often than fertile throughout their reproductive years.
Couples can use the knowledge of their fertility to achieve or avoid a pregnancy.
How does it work?
The Billings Ovulation Method is based on the following facts:
- Primary symptom: sensation of wetness/dryness due to changes in cervical mucus
that indicates the time of ovulation
- Methods include (or are variously named): Billings (Ovulation) Method -see here
also; Creighton Model NFP
- Sympto-Thermal Method.
- Reliability: 97.5-99.5% method-effectiveness in extensive clinical trials.
- Side-effects: None.
- Cost: initial training usually $10-120, though it is frequently provided free
of charge; maintenance costs are practically nil.
- Involves: Corresponsibility of the couple; periodic abstinence; motivation.
- Works for: everyone, including post-partum and pre-menopausal women, illiterate
women; women with irregular cycles, etc.
- Uses: postponing or spacing births; achieving conception in couples with
- Humanitarian advantages: it respects the natural ecology of the body; it is in
harmony with the customs and ethical requirements of all major cultural and religious
traditions (including the Catholic and Moslem faiths)
Couples wishing to avoid pregnancy refrain from intercourse or sexual contact
at the time of fertility.
How do a couple know when they are fertile?
For several days before ovulation a woman's body produces mucus from the cervix
(the opening of the uterus). This mucus gives early awareness of fertility. It is
essential for sperm survival and transport. A couple learn to identify their
fertility and infertility through the woman's observation of this mucus and the
sensations accompanying it. This mucus is apparent at the vulva (the external
opening of the vagina) and, in the course of her ordinary activities, a woman may
be aware of sensations indicating the presence of the fertile mucus.
Can the Ovulation Method be used if you have irregular cycles?
Yes. As the Billings Ovulation Method is based on identifying fertility or
infertility on a day to day basis, all women can learn the method regardless of
their cycle length or irregularity. Women who are ovulating irregularly, or not
at all, can use the method to identify infertility or periods of infertility.
Once learned, the method can be applied to all variations throughout a woman's
- Ovulation occurs only one day in each cycle.
- The ovum lives in the fallopian tube for less than 24 hours if not fertilized.
- Sperm need fertile mucus to survive.
- Sperm without fertile mucus die within a short time.
- Sperm with fertile mucus may live 3-5 days.
- fertility depends on ovulation and satisfactory mucus.
- Shedding the lining of the uterus (menstruation/period) occurs 10-16 days after
- Couples wishing to achieve a pregnancy may wish to have intercourse at the
Does the Billings Ovulation Method have any medical
No. The Ovulation Method is harmless. It does not depend on pills, devices,
invasive examination or surgical procedures.
All in all modern Natural Family Planning (NFP) is safe, healthy, 99% effective
in avoiding pregnancy, as well as in achieving one,a good marriage builder, is
reversible, morally accepted, and cheap. You can accurately gauge your fertility
through easily observable signs and choose to increase or greatly decrease your
fertility while getting to know your body better.
For people who are trying to avoid pregnancy there are only 3 methods of 100%
effective avoidance of pregnancy:
- Regular cycles
- Irregular cycles
- Anovular cycles (no ovulation)
- After childbirth
- While breast-feeding
- After contraceptive medication
- Approaching menopause
- Low fertility
All of these method has a pregnancy rate, including NFP. Though it readers must
bear in mind that the information stated on this page is not rally an adequate one.
You are suggested to refer to more books and professional organization for a
thorough study. The information given here is solely the opinion of the authors
and not any NTP organizations.
Below are somewhat little information gathered by the authors on the basics of
the said method.
- Total abstinence
- Removal of the ovaries (NOT tubal ligation)
- Castration (NOT vasectomy)
EFFECTIVENESS FOR AVOIDING PREGNANCY
The most surprising advantage of NFP to some is that, to avoid pregnancy, it is
actually more effective than most forms of artificial birth control.
For comparison, below is the approximate method effectiveness (percentage of
couples of normal fertility who go one year without getting pregnant, using each
This data was reported by the U.S. Dept. of HEW, and various respected medical
journals. The references are in "The Art of NFP" (ANFP) book. Two studies actually
showed a zero STM pregnancy rate, but realistically ALL methods, even tubal and
vasectomy, have a surprise pregnancy rate (except the last 3).
The most effective reversible birth control method is a version of the
Sympto-Thermal Method that allows intercourse only after the rules determine
ovulation. Most couples don't want to follow such a strict regimen and are willing
to accept a small risk of pregnancy, so they choose a variation that suits their
needs. The effectiveness is really your choice.
A recent but typical study found "...natural family planning can be extremely
effective in the Third World. The study was of 19,843 predominantly poor women in
Calcutta...The pregnancy rate was similar to that with the combined contraceptive
pill --0.2 pregnancies/100 women users yearly." (British Medical Journal,
Sept. 18, 1993, by R.E.J. Ryder.)
User rates for all methods are lower. The user rate is the actual rate in
practice by couples who sometimes misuse a method (forget a pill, diaphragm in
wrong, condom without spermicide, misinterpret NFP rule, etc.). Another reason for
lower user rates is that some studies had only limiters and others only spacers.
Limiters intend to limit family size; spacers generally want kids "soon" and are
apt to use more liberal rules and take chances, and will eventually use NFP to
increase their fertility. Lumping in spacers, some studies have shown NFP
effectiveness as low as 85%, which is most often quoted in literature designed to
sell artificial contraception. However, artificial methods also have low
effectiveness rates if not used carefully.
You can reach the "99%" effectiveness level (better than artificial methods) if
you learn NFP properly and practice it according to the rules. It is NOT contingent
on your having regular cycles. You can also use NFP to help get pregnant when
desired, and pay attention on your daily nutrition to increase your fertility.
Additional information substantiating the excellent effectiveness of NFP can be
found at the CCL and Family of the Americas web pages.
| No birth control method
| Calendar Rhythm (Ogino-Knaus)
| Ovulation (or Billings) method
| Diaphragm with spermicide
| LAM (breastfeeding) (first 6 months)
| I U D
| Sympto-Thermal method
| Tubal Ligation
| Castration, removal of ovaries, abstinence:
Natural methods do not interfere with a person's health in any way. In fact,
you get to know your cycles so that you know when something's not totally right.
And if your cycles are really weird, NFP can be used, but it alerts you and your doctor.
By using NFP, women learn things about their individual bodies which can be useful
when trying to acheive pregnancy. NFP doesn't have side effects that can reduce fertility
in the long-term, as some artificial birth control methods can.
NFP users generally reports a positive impact on a relationship. It operates a
totally different way from contraception, which acts as a barrier (physically and
emotionally) between you. Because NFP is a cooperative system, it helps you to love,
respect, appreciate, and communicate better. You learn it together, interpret the
charts together, and decide to postpone or seek pregnancy together. The divorce rate
among NFP users is far less than the average partly because of this.
The reason most people who avoids pregnancy refuses to try NFP is probably due
to the periodic abstinence from sexual relations that is required. We turn that
around and count it as an advantage instead. It prevents the partners from developing
a pattern where one person is always desirous of intimacy and the other is always
seeking more space, by creating times when both people feel strong desires. A "courtship"
and a "honeymoon" each month helps keep a marriage from getting stale. It also forces
you to develop different aspects of your relationship at different times.
Couples trying to achieve pregnancy can feel there is no pressure on them
during most of the month, when they know what part of the month they're fertile.
Charting fertility signs can let people know whether they're pregnant or not, much
sooner than they would otherwise know, thus reducing uncertainty and anxietyboth
for those seeking and avoiding pregnancy.
Classes, books and materials are anywhere from free to $60, and after that it
takes a $3 book of charts per year. You save the cost of home preg. tests,
fertility specialists and drugs, birth control pills, doctor visits & surgery.
This really is a disadvantage, making NFP instructors hard to find because, unlike
the huge contraceptive industry, they cannot advertise due to low cash flow.
CYCLES: BASIC FERTILITY AWARENESS
In a typical menstrual cycle, a woman has several days of bleeding, followed
usually by a few infertile days, then several days during which fertile cervical
fluid is produced, then ovulation. About 2 weeks after ovulation the cycle ends
and the bleeding of the next cycle begins.
If you have intercourse when no fertile cervical fluid is being produced, (and
this usually includes the days of bleeding), the sperm quickly die, and pregnancy
is highly unlikely. When fertile cervical fluid is present, the sperm gradually
dies but can still live in it for up to 6 days. Therefore you are fertile when
fertile cervical fluid is being produced, even several days before ovulation. The
egg lives only about one day. Ovulation may occur again up to a day later, and that
egg dies a day later. After that, it's impossible for you to become pregnant for
the rest of that cycle.
The different parts of this cycle are usually determined using two main
symptoms. The first is basal body temperature, an easy and reliable indicator that
ovulation has occurred. The woman's temperature is taken immediately upon waking,
at the same time every morning. It only goes up about a half degree Fahrenheit,
which is most accurately read with a basal body temperature (BBT) thermometer. It
generally stays up for 2 weeks (the "luteal phase"), then might dip just before
menses starts again.
The second symptom is observation of the quality of the cervical fluid itself.
This takes more experience than just reading a thermometer, but most people with
good instruction are doing well after 3 to 4 cycles. The fertile cervical fluid
lasts around 3 to 7 days, and is like stretchy egg white. The less fertile cervical
fluid is tacky, opaque, and generally less abundant.
In the usual cycle, cervical fluid builds up to a peak, ovulation occurs, then
the cervical fluid dries up and BBT goes up. However, ovulation can be delayed due
to a number of things, or a cervical fluid patch may start then dry up, then start
again; you just wait for the BBT rise to signal ovulation. Postpartum cycles
(including nursing, which prevents ovulation temporarily) and menopause are normal
things that can be successfully charted.
Several different rules for finding the relatively fertile and infertile times have
been developed and fine tuned over the years, based on thousands of charts and much
medical research. You can choose each cycle whether to seek or avoid pregnancy, and how
conservative to be. We haven't told you everything you need to know to interpret the
cervical fluid or temperature signs. That's something we're leaving to adequate instruction
(books or class).
Since men are normally always fertile, NFP methods depend on finding out when
the woman is fertile or possibly fertile, and having intercourse only on days when
she is known to be infertile.
The now obsolete Calendar Rhythm used each woman's past cycle history to
predict future cycles. Its method effectiveness, up to 87%, was similar to that of
its competitors in the 30's and 40's. The Calendar Rhythm method, practiced correctly,
uses the shortest and longest cycle in the past year or two to design rules for
each woman. If a woman has a cycle much shorter or longer than her normal length,
she can then get pregnant. Unfortunately, it was taught and practiced haphazardly,
resulting in much worse effectiveness.
Instead, modern NFP assumes women are not perfectly regular. It accurately gauges
your fertility as it happens, using readily observed symptoms.
In the Ovulation Method (OM), also known as the Billings method, the woman not
only observes when she is bleeding, but also observes when she's producing fertile
cervical fluid. Many women are keptical that they can really observe their cervical
fluid, but after daily charting and the guidance of a qualified teacher, they get to
be pros after a few cycles. Thus the fertile time is determined with good accuracy.
The days of bleeding are days of low probability of being fertile; one isn't quite
sure on those days. Without the confirmation of ovulation, bleeding which otherwise
seems to be menstruation could really be bleeding at the time of ovulation, or bleeding
for some other reason. So they're called "days of bleeding" rather than "menstruation,"
and require abstinence. Also, in a very short cycle, fertile cervical fluid may begin
to be produced before menstruation has finished, and it may be difficult to observe in
the presence of bleeding.
The OM is much more effective than rhythm was, because the actual fertile time is
detected. If there's an unusually long or short cycle where the rhythm method would
fail, the OM nevertheless requires abstinence during your fertile time, as detected by
the cervical fluid pattern. An added advantage is that the OM allows intercourse from
the end of bleeding all the way up to the time that your fertile time begins, which
happens when the sperm-sustaining fertile cervical fluid appears.
Using cervical fluid observations like the OM but crosschecking them by temperature
is called the Sympto-Thermal Method (STM), and is more accurate than using either sign
alone. Occasionally there's more than one cervical fluid patch, but ovulation occurs
only after the last one. Without the temperature crosscheck, you would assume ovulation
was after the first cervical fluid patch.
The Sympto-Thermal method uses daily temperature measurements, taken upon waking in
the morning at the same time every day. It also relies on symptoms of fertility, most
commonly the presence of fertile cervical fluid, and the position of the cervix. Around
the fertile time, the cervix withdraws further into the body and its opening widens.
At the time of ovulation, temperature starts to rise about half a degree Fahrenheit.
Crosschecked with the other symptoms, this provides confirmation that ovulation has
occurred and determines the infertile time following ovulation. The precise sympto-thermal
rules require waiting 3, 4 or more days, depending on the situation, after the first
sign that ovulation seems to have occurred, while continuing to collect information
to confirm it. This also allows for multiple ovulations.
The infertile time in the early part of the cycle is less certain, but can
still be found with effectiveness rates that compare well with other methods. The
version with the lowest effectiveness rate allows intercourse up to the last day
that is free of fertile signs such as cervical fluid. This rule is similar to the
Billings Method. Stricter rules are available for those who want them; these rules
involve beginning abstinence a few days before the first fertile signs are expected.
In the STM intercourse is often allowed during menstruation. Unlike the OM, you
can tell that bleeding is really menstruation, because the rise of temperature in
the previous cycle confirms that ovulation has occurred.
A possible new approach is examining dried saliva or cervical fluid with a
magnifying lens. The crystallization patterns theoretically change depending on
whether the woman is in the fertile part of her cycle. But user experience and
medical studies have not yet shown this to be easily used or effective, as the
other symptoms are.
LACTATION AMENORRHEA METHOD
Recently, researchers have defined what they call the "Lactation Amenorrhea
Method" (LAM). Used since the beginning of humanity, breastfeeding still prevents
more pregnancies than all artificial methods of birth control put together.
After giving birth, a woman normally experiences a time of infertility until
her body is ready for another pregnancy. If you don't breastfeed, it's usually
quite short. If you exclusively breastfeed your baby, without pacifiers, bottles,
babysitters, or schedules, the average length of infertility is 14 months. It
varies a lot, though, from a few months to several years. If fertility returns
during the first 6 months while breastfeeding a lot, it usually starts with
menstruation before the first ovulation. That provides a warning that fertility is
The rules for LAM are simple: If a woman has given birth in the last 6 months,
is fully breastfeeding her baby (no formula, solid food, etc.) and has not yet
menstruated, she can assume she has 98% family planning effectiveness from
You can achieve higher effectiveness by following guidelines of "ecological
mothering": nursing on demand, nursing at night, nursing in a lying-down position
for naps and at night, no bottles or pacifiers. The longest time between feedings
each day may be the strongest factor leading to the return of fertility, so if the
baby stops nursing during the night, the return of fertility becomes more likely.
Your fertility will return eventually, of course, and you can delay subsequent
pregnancy by watching for the return of fertility. If you've practiced NFP before
your pregnancy this is easy. Otherwise, you need the guidance of a qualified
Not only is breastfeeding good birth control, it is highly beneficial to your
baby`s physical and emotional health by providing nutrients, antibodies, and
nurturing. Birth control pills adversely affect nursing and milk nutrients, but
you need not stop nursing; you simply don't need the Pill.
UNICEF has estimated that each year, 1.5 million babies die worldwide because
they weren't breastfed. Use of LAM provides an additional incentive and source
of support for breastfeeding.
Conception occurs right after ovulation, as the egg enters the fallopian tubes.
With good timing, sperm will be waiting there to fertilize it. The egg only lives
a day or so, but sperm can live several days in the fertile type cervical fluid. So
achieving pregnancy is a matter of timing coitus just before ovulation.
If the woman has very short cervical fluid patches (assuming she knows what to
look for), this could adversely affect her fertility. Dry-up drugs like antihistamines,
or not drinking enough water, can reduce the amount of cervical fluid. Improved
nutrition and guaifenesin (e.g., Robitussin cough syrup) can sometimes help to
Finding exact ovulation time is impossible without a laparoscope, but you've
got a few days of sperm life to work with. Possible signs of ovulation are:
- A temp dip toward the end of cervical fluid pattern
- First day of cervical fluid dryup
- First day of temp rise (usually too late)
ESTIMATED DATE OF CHILDBIRTH
Pregnancy doesn't "begin" at the last menstrual period (LMP); that's the basis
of the old-fashioned Naegele's Rule. The time between menses and ovulation can vary,
and a woman may even have breakthrough bleeding when she is expecting her next
period. The EDC by the Prem rule is the first day of temperature rise minus 7 days
plus 9 months. (That's 38 weeks after conception, not LMP.) 65% of deliveries will
be plus or minus one week from EDC; 90% +/- 2 weeks; 95 +/-3 weeks; 99% +/-4 weeks.
Fertility varies widely, and about 10% of couples have fertility problems.
Talking with NFP teachers (or reading books) may reveal a better picture of what
your fertility is, and what your prospects for improving it are. It depends
on a lot of factors, and self-awareness of your cycles is the first step. There is
a lot you can do without resorting to expensive, ineffective fertility clinics and
Your charts, properly interpreted, show what your cycles are like. Look for
anovulatory cycles, length of cervical fluid patches, breakthrough bleeding,
delayed ovulation, or symptoms of approaching menopause. Short luteal phases or
unusually low BBT (around 97.2 degrees or lower) may be related to infertility and
can often be treated with vitamins and other nutrients, or changes in lifestyle.
A gradual decrease in fertility occurs with age, but until menopause there's
still a chance. An MD told a friend of Jim and Mary that over 40, women don't
ovulate, but they have 60 charts that show otherwise.
The hormone contraceptives (Pill, Norplant) can have unwanted permanence, and
previous IUD use can cause repeated miscarriages. Another good reason not to use
Your health and nutrition is important. Drugs, tobacco, alcohol, and caffeine
use affect fertility. Stress and excitement can result in anovulatory cycles.
Improving your diet and/or taking certain vitamin and mineral supplements can
improve fertility; for example, the father must have sufficient vitamin C in
hisdiet or the sperm can't swim. For the woman, too much exercise or not enough
body fat (min. 20%) can reduce fertility.
If you have low fertility due to low sperm production, irregular cycles, or
low cervical fluid there may be additional (and cheap) things you can do to correct
Before using high-tech infertility treatments, charting the women's cycles can
help determine what is causing the infertility, and thus provide a guide as to what
techniques may be useful. For example, if charting shows that the woman is actually
getting pregnant but is having very early miscarriages, then In-Vitro Fertilization
won't be much use, but other medical treatments may help. Short luteal phases,
unusually low basal temperatures or lack of fertile cervical fluid are different
conditions that can be related to infertility and that have different nutritional
or medical treatments.