NATURAL FAMILY PLANNING
Natural Family Planning (NFP) is a term used to describe
methods of planning or postponing pregnancy based on
observation of naturally occurring signs and symptoms
of the fertile phases of the menstrual cycle. Techniques
include the Basal Body Temperature method, the Billing's
Ovulation Method, the Symptothermal Method and the Rythm
Method. It is important to note that NFP is not A METHOD
OF CONTRACEPTION but rather A TECHNIQUE FOR DETERMINING
THE FERTILE PERIOD.
There are four methods of NFP:
- Basal Body Temperature (BBT).
- Billings Ovulation Method (BOM).
- Symptothermal Method (STM).
- Calender or Rythm Method.
Basal Body Temperature (BBT)
BBT method is a method to detect ovulation by observing
thermal shift of 0.04° F (Av 0.02° F-1°
F) at luteal phase following ovulation. This thermal
rise remains at a higher level till the end of the cycle
and begins to fall to the pre-ovulatory level 2-3 days
before the next menses begins. Thus, the temperature
chart shows a biphasic pattern. This method has abstinence
during first half of menstrual cycle till 3 days of
elevated temperature. Maintaining and interpreting temperature
requires lot of care. Moreover 7 to 10% ovulatory cycles
can be monophasic.
Billings Ovulation Method (BOM)
This relies on changes in consistency and volume of
cervical mucus in relationship to ovulation. On the
basis of cervical mucus, dry days and wet days (fertile
phase) are recognised by women. Wet days start with
sticky white mucus for 2 to 3 days following 2 to 3
dry days after a menses. Sticky white mucus days are
followed by clear, slippery, profuse mucus (capable
of being stretched between 2 fingers) for 3 to 5 days,
the last day is called peak day. To postpone pregnancy,
the couple should abstain from sexual intercourse on
all days of noticeable mucus and for three days thereafter.
The woman cannot recognize ovulation directly but every
woman who ovulates produces mucus and she can recognise
its presence from the wetness and sensation of lubrication
in the vagina. On identifying the mucus, she can identify
ovulation time, which is possibly the fertile time,
the time of conception.
The three different phases of fertility in a menstrual
The First Phase
This phase is relatively infertile and extends
from the first day of the menses till the cervical mucus
begins and is called the pre-ovulatory infertile phase.
Following menstruation, there are 2 to 3 dry days called
early dry days.
The Second Phase
This phase is fertile and extends from the beginning
of the mucus sequence and ends, a few days after the
mucus ceases. It is in this phase that ovulation occurs.
The degree of fertility at this phase increases progressively,
because at the start of the mucus sequence, the mucus
is thick and sticky, opaque, non-stretchy which prevents
sperm-entry into the uterus to a very great extent.
Fertility is present, but it is very low. The fertility
increases as the mucus becomes progressively more watery
(thin), clear, slippery and stretchy like raw egg-white.
Maximum fertility is present when these features are
seen to an optimum degree which is usually a day before
the actual day of ovulation and is called peak day.
The Third Phase
This phase is infertile and extends from the end of
the fertile phase until the last day of the cycle, before
the next menstrual period begins. It is called the post-ovulatory
infertile phase which begins from the 4th day after
peak. Thus, in a menstrual cycle, one sees a fertile
phase occurring between two infertile phases.
Rule: Abstain during the menstrual period
The word "abstain" used above means the avoidance
not only of the marital act but also of any genital contact.
During early dry days the marital act can be had, but
on alternate nights.
Rule: Abstain from all genital contact
on all mucus days and also on the three days immediately
Is known as the "Completely Infertile Part"
(CIP) of the cycle and the marital act will not result
Symptothermal Method (STM)
This combines the Thermal Shift, Mucus Symptom and
a few other secondary symptoms such as pain, spotting
of blood and mood changes. An enlarged pea sized lymph
node can be felt in the groin on the same side as the
ovary containing the maturing follicle in some women.
These secondary symptoms are not constant.
Calender or Rythm Method
The fertile period is calculated based on the previous
twelve menstrual cycle records. The first unsafe day
is obtained by subtracting 20 days from the length of
the shortest cycle and the last unsafe day by deducting
10 days from the longest cycle.
This method is not reliable as it is based on calculations
from the previous cycles and cannot be used by people
who have irregular cycles.